U.S. patent number 7,199,934 [Application Number 11/122,502] was granted by the patent office on 2007-04-03 for head-mounted display apparatus.
This patent grant is currently assigned to Olympus Corporation. Invention is credited to Masafumi Yamasaki.
United States Patent |
7,199,934 |
Yamasaki |
April 3, 2007 |
Head-mounted display apparatus
Abstract
A head-mounted display apparatus comprises a see-through image
display portion for setting a display frame in a display-capable
range, and displaying an image in such a manner that the image is
superimposed on an image of the external environment in the display
frame, an angular velocity sensor for detecting the tilting angle
of the head of an observer; an LCD driver, a second CPU and the
like which control the display frame to move in an amount
corresponding to the angle detected by the angle detection means in
the direction opposite to the tilting direction of the observer's
head, whereby the position of a virtual image, observed by the
observer, is kept substantially constant, irrespective of the
tilting of the observer's head, and first CPU which controls the
apparatus so that the mode of the apparatus is automatically
changed to a low consumption power mode.
Inventors: |
Yamasaki; Masafumi (Hachioji,
JP) |
Assignee: |
Olympus Corporation
(JP)
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Family
ID: |
35239186 |
Appl.
No.: |
11/122,502 |
Filed: |
May 5, 2005 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20050248852 A1 |
Nov 10, 2005 |
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Foreign Application Priority Data
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May 6, 2004 [JP] |
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2004-137768 |
Jun 11, 2004 [JP] |
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2004-174564 |
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Current U.S.
Class: |
359/630;
345/7 |
Current CPC
Class: |
G02B
27/0093 (20130101); G02B 27/017 (20130101); G06F
3/012 (20130101); G02B 2027/014 (20130101); G02B
2027/0187 (20130101) |
Current International
Class: |
G02B
27/14 (20060101); G09G 5/00 (20060101) |
Field of
Search: |
;359/630-634 ;345/7,8,9
;349/11 ;348/115 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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06-078247 |
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Mar 1994 |
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JP |
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2003-248194 |
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Sep 2003 |
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JP |
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Other References
"Psychological Physics of Visual Sense"; Mitsuo Ikeda; Newest
Applied Physics Series 3; Morikita Shuppan; 1975; p. 194. cited by
other.
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Primary Examiner: Mack; Ricky
Assistant Examiner: Hasan; M.
Attorney, Agent or Firm: Ostrolenk, Faber, Gerb &
Soffen, LLP
Claims
What is claimed is:
1. A head-mounted display apparatus comprising: an angle detector
to detect the tilting angle of the head of an observer; a display
portion to display a predetermined image in such a manner that the
predetermined image is superimposed on an image of an external
environment, the display portion being changed from a display-state
of the predetermined image to a non-display-state thereof and
vice-versa, corresponding to the tilting angle of the observer's
head detected by the angle detector; and a controller to control
the display portion in such a manner that, in the case in which the
non-display state of the display portion continues for not less
than a predetermined time-period, the non-display state is
continuously kept, even if the tilting angle of the head,
thereafter, gets to have a value corresponding to the display-state
thereafter.
2. The head-mounted display apparatus according to claim 1, wherein
the display portion is changed so as to be in the display-state
when the tilting angle of the observer's head detected by the angle
detector is within a predetermined angle range and so as to be in
the non-display state when the tilting angle departs from the
predetermined angle range.
3. The head-mounted display apparatus according to claim 1, wherein
the display portion displays the image in such a manner that the
image is moved in an amount corresponding to the angle detected by
the angle detector in the direction opposite to the tilting
direction of the observer's head, whereby the relative position of
the predetermined image with respect to the image of the external
environment, observed by the observer, is kept substantially
constant, irrespective of the tilting of the observer's head.
4. The head-mounted display apparatus according to claim 1, wherein
the controller controls the head-mounted display apparatus so that
the power supply of the head-mounted display apparatus is turned
off, or so that the head-mounted display apparatus is set in a low
consumption power mode, when the non-display state of the display
portion continues for not less than the predetermined
time-period.
5. The head-mounted display apparatus according to claim 2, wherein
the controller controls the head-mounted display apparatus so that
the power supply of the head-mounted display apparatus is turned
off or so that the head-mounted display apparatus is set in a low
consumption power mode, when the non-display state of the display
portion continues for not less than the predetermined
time-period.
6. The head-mounted display apparatus according to claim 3, wherein
the controller controls the head-mounted display apparatus so that
the power supply of the information display apparatus is turned off
or so that the information display apparatus is set in a low
consumption power mode, when the non-display state of the display
portion continues for not less than the predetermined
time-period.
7. The head-mounted display apparatus according to claim 1 further
comprising time-set portion to set the predetermined time-period at
a desired value.
8. The head-mounted display apparatus according to claim 2 further
comprising time-set portion to set the predetermined time-period at
a desired value.
9. The head-mounted display apparatus according to claim 3 further
comprising time-set portion to set the predetermined time-period at
a desired value.
10. The head-mounted display apparatus according to claim 4 further
comprising time-set portion to set the predetermined time-period at
a desired value.
11. The head-mounted display apparatus according to claim 5 further
comprising time-set portion to set the predetermined time-period at
a desired value.
12. The head-mounted display apparatus according to claim 6 further
comprising time-set portion to set the predetermined time-period at
a desired value.
Description
This application claims benefit of Japanese Application No.
2004-137768 filed in Japan on May 6, 2004, Japanese Application No.
2004-174564 filed in Japan on Jun. 11, 2004, the contents of which
are incorporated by this reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a head-mounted display apparatus,
and more particularly, to a head-mounted display apparatus which
displays images in a manner such that they can be observed while
wearing the apparatus on one's head.
2. Description of the Related Art
Hitherto, display apparatuses which are mounted to heads and by
which images are observed, such as HMD (Head-Mounted Display) and
HUD (Head-Up Display) have been known.
This type of display apparatuses are described, for example, in
Japanese Unexamined Patent Application Publication No. 2003-248194.
In the image display apparatus described in the Publication, an
image disposed on a spectacle frame is projected to a hologram
optical element as a combiner. The image reflected by the hologram
optical element is guided to an observer's eye, so that this image
as a virtual image is superimposed on the view of the external
environment.
On the other hand, Japanese Unexamined Patent Application
Publication No. 6-78247 describes a head-mounted display apparatus
with which the operation of changing over an electronic image to an
external environment image can be easily performed. Also, the
Publication describes a technique by which a virtual screen can be
observed as if it were stationary at a predetermined position of
the external environment, although the tilting angle of an
observer's head changes, and moreover, an image of the external
environment can be observed on the outside of the virtual screen
(see Step Nos. 0035 to 0044, particularly, Paragraph No. 0041 in
the Publication).
As regards human eyes, optic cells especially having a high visual
acuity, which are called pyramids, are distributed on the center of
a retina at a high density, and the distribution-density of the
optic cells remarkably decreases toward the periphery of the
retina. There are three types of pyramids, of which the spectral
sensitivity characteristic peaks exist in the R, G, and B. Thus,
the sense of color is effective in the range having a radius of
20.degree. to 30.degree. around the center of the retina. The range
having a radius from the center of up to 3.degree. in which the
pyramids are distributed at a very high density is called a center
orbit. High-sensitive cells, called rods, which are reactive with
brightness and are effective mainly in seeing in dim light, are
distributed more and more in the direction of from the center
toward the periphery, instead of the pyramids. The density of the
rods is the highest in the position from the retina-center of about
20.degree., and is gradually reduced toward the periphery. The
visual acuity of a human eye having the above-described structure
is varied with brightness. It is known that when the brightness is
high, the visual acuity is highest in the center orbit, and
remarkably decreases near the periphery. FIG. 34 illustrates the
visual acuity at the respective positions on the retina plotting
the brightness as a parameter (Ikeda Mitsuo: "Newest Applied
Physics (Saishin Oyo-Buturigaku) Series 3", Psychological Physics
of Visual Sense (Shikaku no Shinri-Butsurigaku), p. 194, 1975,
published by Morikita Shuppan). As seen in FIG. 34, when the
brightness is relatively high, the pyramids distributed at a high
density near the center orbit effectively act. Thus, the visual
acuity is very high especially in the center of the retina.
However, when the brightness is low, the pyramids do not
effectively act, so that the difference between the visual acuities
in the center and in the periphery is not significant. Then, it is
generally known that the two-point discrimination resolving-power
of the center orbit is about 1'.
In recent years, from the standpoint of the global environment
protection, the saving of consumption energy has been attempted in
various types of devices and apparatuses. Specifically, for
example, there is known a technique in the personal computer field,
by which PCs are automatically set in a low consumption power mode,
when no input-operation is carried out through a keyboard, a mouse,
or the like for a predetermined time-period.
According to the known HMD and HUD, even if the head is moved to a
small degree, the observed virtual view is moved together with the
head. Thus, the screen is observed as if it went around the head.
Particular, when the observer wears the device for a long time, the
screen becomes a factor in stress to the observer.
Moreover, the above-described known display apparatuses have a
small size and a light weight, and are satisfactorily portable.
Thus, the observer tends to move in an ordinary manner while
wearing the apparatus. However, if the display screen continues to
be displayed in the field of sight of the observer, the screen may
disturb the ordinary movement. In order to eliminate such
disturbance, it is necessary to remove the display apparatus or
switch off the power supply of the apparatus before the ordinary
movement is made. However, in the case of the spectacle as an
example, it is troublesome to take off the spectacle prior to each
movement. Similarly, it is troublesome to remove the display
apparatus or switch off the power supply of the apparatus every
time the ordinary movement is made.
In the known display apparatuses, similarly, it is necessary to
switch off the power supply for example, for the purpose of
reducing the consumption power. However, it is troublesome to
frequently switch off the power supply. It is unsuitable to apply
the above-described technique for reducing the consumption power
used in personal computers, that is, the technique by which the
power supply is controlled in the case in which input-operation is
not executed for a predetermined time-period, to information
display apparatuses for which intentional input-operation is not
necessarily carried out. For display apparatuses which use
batteries or the like as power supply and are portable, it is very
important to reduce the supply power.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a
head-mounted display apparatus in which the observation of an image
and that of the external environment can be simply changed over,
and also the power consumption can be effectively reduced.
Briefly, the head-mounted display apparatus of the present
invention comprises: an angle detector to detect (sometimes
referred to interchangeably herein as "detection means") the
tilting angle of the head of an observer; a display portion to
display (sometimes referred to interchangeably herein as "display
means") a predetermined image in such a manner that the image is
superimposed on an image of the external environment, the display
portion for switching a display-state in which the image is
displayed and a non-display-state in which the image is not
display, corresponding to the tilting angle of the observer's head
detected by the angle detector; and a controller (sometimes
referred to interchangeably herein as "control means") for
controlling the display portion whereby, in the case in which the
non-display state of the display portion continues for not less
than a predetermined time-period, the non-display state is
continuously kept, even when the tilting angle of the head gets to
have a value corresponding to the display-state.
The above and other objects, features, and advantages of the
invention will become more clearly understood from the following
description referring to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view illustrating a state in which a
head-mounted information display apparatus in accordance with an
embodiment of the present invention is used;
FIG. 2 is a front view illustrating the head-mounted portion
thereof in the same embodiment;
FIG. 3 is a plan view illustrating the head-mounted portion thereof
in the same embodiment;
FIG. 4 is a right side view illustrating the head-mounted portion
thereof in the same embodiment;
FIG. 5 is a plan view illustrating a controller/recorder when an
operation panel is closed in the same embodiment;
FIG. 6 is a right side view illustrating the controller/recorder
when the operation panel is closed in the same embodiment;
FIG. 7 is a left side view illustrating the controller/recorder
when the operation panel is closed in the same embodiment;
FIG. 8 is a plan view illustrating operation switches disposed on
the operation panel in the same embodiment;
FIG. 9 is a perspective view illustrating the controller/recorder
when the operation panel is opened in the same embodiment;
FIG. 10 is a plan view illustrating the configuration of a remote
controller in the same embodiment;
FIG. 11 is a block diagram illustrating the configuration of,
mainly, an electronic circuit of the head-mounted camera of the
same embodiment;
FIG. 12 illustrates the pitch direction;
FIG. 13 illustrates the yaw direction;
FIG. 14 illustrates the principle of an optical system of a
see-through image display portion in the same embodiment;
FIG. 15 is a front view, partially in section, illustrating the
optical system of the see-through image display portion in the same
embodiment;
FIG. 16 is a left side view illustrating an example of the
configuration of the optical system of the see-through image
display portion in the same embodiment;
FIG. 17 is a left side view illustrating another example of the
configuration of the optical system of the see-through image
display portion in the same embodiment;
FIG. 18 is a cross-sectional plan view illustrating the
configuration of the optical system of the see-through image
display portion in the same embodiment;
FIG. 19 is a plan view, partially in section, illustrating the
structure of a joint portion containing a front portion, a hinge,
and a temple in the same embodiment;
FIG. 20 is a view showing the joint portion containing the hinge
and the temple seen from the left side substantially in the right
direction in FIG. 19;
FIG. 21 illustrates an example of an original image to be displayed
in the same embodiment;
FIG. 22 illustrates the correspondence between the pixels of LCD
and the original image in the same embodiment;
FIG. 23 illustrates an example of the correspondence between a
projection image as a virtual image and the original image in the
same embodiment;
FIG. 24 illustrates another example of the original image to be
displayed in the same embodiment;
FIG. 25 illustrates another example of the correspondence between
the pixels of the LCD and the original image in the same
embodiment;
FIG. 26 illustrates another example of the correspondence between
the projection image as a virtual image and the original image in
the same embodiment;
FIG. 27 shows an example of a test chart in the same
embodiment;
FIG. 28 illustrates a straight line in the horizontal direction in
the test chart shown in FIG. 27 obtained before and after
modification;
FIG. 29 is a flowchart illustrating processing for adjusting the
initial position of a display screen in the same embodiment;
FIG. 30 is a flowchart illustrating processing for controlling the
display position of an image in the same embodiment;
FIG. 31 is a flowchart illustrating an example of processing for
controlling the display or non-display of an image in the same
embodiment;
FIG. 32 shows an example of a screen displayed when the initial
position of the display screen is adjusted in the same
embodiment;
FIG. 33 shows an example of a screen displayed when the initial
position of the display screen has been adjusted in the same
embodiment; and
FIG. 34 is a diagram illustrating the visual acuity in different
portions of a retina which varies with the brightness as a
parameter in the related art.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, an embodiment of the present invention is described
with reference to the drawings.
First Embodiment
FIGS. 1 to 33 illustrate an embodiment of the present invention.
FIG. 1 is a perspective view illustrating a state in which a
head-mounted information display apparatus is used.
The head-mounted information display apparatus of this embodiment
is an information display apparatus of a head-mounted type (a
head-mounted information display apparatus), as described
below.
The information display apparatus 1 includes, as shown in FIG. 1, a
head-mounted unit 2 formed substantially in the shape of a pair of
spectacles, a controller/recorder 4, which serves as the main body
of the information display apparatus 1, connected to the
head-mounted unit 2 via connecting means, such as a cable 3, and a
remote controller 5 for remotely performing input operations for
the information display apparatus 1.
The head-mounted unit 2 allows a user to observe a subject (in the
external environment) substantially directly in a see-through
display mode and also to observe a piece of information in
superimposition on the subject. The head-mounted unit 2 can be worn
on the head in a manner similar to ordinary eyesight-correcting
spectacles, as is seen from the shape of the head-mounted unit 2.
The head-mounted unit 2 is light and small so that the weight and
the size thereof can be as close as possible to those of actual
spectacles.
A connecting terminal 3a provided at one end of the cable 3 is
connected to a cable connecting terminal 21 (see FIG. 2) of the
head-mounted unit 2, and a connecting terminal 3b provided at the
other end of the cable 3 is connected to a cable connecting
terminal 49 (see FIG. 6) of the controller/recorder 4, thereby
connecting the head-mounted unit 2 with the controller/recorder 4.
As means for electrically connecting the head-mounted unit 2 with
the controller/recorder 4, although wired means such as the cable 3
is used, wireless means for wirelessly connecting the two elements
may be used.
The controller/recorder 4 controls the entire information display
apparatus 1, and also can regenerate a piece of information to be
observed by means of the head-mounted unit 2. The
controller/recorder 4 is also formed to be as light and small as
possible so that it can be used under various conditions. For
example, it can be attached to a belt at the user's waist or it can
be stored in an inner pocket of a jacket. The controller/recorder 4
can also be stored in a bag by using a long cable 3.
The remote controller 5 allows an observer to remotely control with
an observer's hand, operations that are comparatively frequently
performed on the information display apparatus 1. Accordingly, the
remote controller 5 is formed to be light and small so that it can
be held in the palm of the hand, and wirelessly communicates with
the controller/recorder 4.
In this embodiment, the head-mounted unit 2, the
controller/recorder 4, and the remote controller 5 are separately
provided from each other. This makes the user comfortable when
wearing the head-mounted unit 2, which is formed light and small,
and also allows the user to easily operate this information display
apparatus 1 by using the remote controller 5.
The external appearance and the overview of the head-mounted unit 2
are described below with reference to FIGS. 2 through 4. FIGS. 2,
3, and 4 are a front view, a plan view, and a right side view,
respectively, illustrating the head-mounted unit 2.
The head-mounted unit 2 includes a front portion 11 corresponding
to lens, rims, a bridge, and joint portions of regular spectacles
and temples 12 extended from the left and right sides of the front
portion 11 in the backward direction (opposite to the subject) and
foldable with respect to the front portion 11.
The front portion 11 includes a frame 13, and transparent optical
members 14 and 15 which serve as optical waveguide members and
attached to the frame 13 in association with the right and left
eyes.
The frame 13 is provided substantially at the center with a nose
pad 19 for placing the head-mounted unit 2 on a nose-ridge, and a
bridge 20 across the upper portion of the space between the
transparent optical members 14 and 15.
The temples 12 are connected to the front portion 11 via hinges 24
and 25 so that they are foldable with respect to the front portion
11. That is, the temples 12 can be folded toward the central
portion of the front portion 11 i.e., they can be folded along the
front portion 11 to become small, thereby making the head-mounted
unit 2 easy to store and carry. End covers 26 and 27 for placing
the head-mounted unit 2 on the ears are provided at the distal ends
of the left and right temples 12.
Electric equipment 30a is integrally formed on the temple 12 on the
left-eye side (that is, on the right side in FIGS. 2 and 3). Also,
electric equipment 30b is integrally formed on the temple 12 on the
right-eye side (that is, on the left side in FIGS. 2 and 3). These
electric equipments 30a and 30b accommodates electric circuits for
mainly controlling the see-through display. Therefore, when the
temples 12 are folded, the electric equipments 30a and 30b are also
folded with the temples 12. As described above, the information
display apparatus 1 can be compactly accommodated, since the
electric equipments 30a and 30b are disposed on the foldable
temples 12.
A cable connecting terminal 21 to be connected to the connecting
terminal 3a disposed on the one end of the cable 3 is provided in
the lower end on the rear side (on the side which is near the ear
of the observer) of the electric equipment 30a. The electric
circuit of a see-through image-display unit 6 (see FIG. 11), which
will be described below, is dispersedly arranged within the inside
of the front portion 11 and in the electric equipments 30a and 30b,
so that the entire head-mounted unit 2 can be well balanced in size
and weight, and hence, an observer wearing the head-mounted unit 2
feels comfortable.
The space between the right side of the front portion 11 and the
hinge 24 and the space between the left side of the front portion
11 and the hinge 25 are formed into boxes, having a structure shown
in FIGS. 19 and 20 described below, for accommodating flexible
printed circuit boards or the like connecting the respective
circuits on the inside of the front portion 11, and the respective
circuits in the electric equipments 30a and 30b to each other.
The external appearance and the overview of the controller/recorder
4 are described below with reference to FIGS. 5 through 9. FIGS. 5,
6, and 7 are a plan view, a right side view, and a left side view,
respectively, illustrating the controller/recorder 4 when an
operation panel 42 is closed. FIG. 8 is a plan view illustrating
operation switches disposed on the operation panel 42. FIG. 9 is a
perspective view illustrating the controller/recorder 4 when the
operation panel 42 is opened.
The controller/recorder 4 is formed of a controller/recorder main
unit 41 and the operation panel 42 provided for the
controller/recorder main unit 41 via a hinge 43 so that it can be
opened and closed.
The controller/recorder main unit 41 has built-in circuits, which
are described below, and also includes a liquid crystal display
device (hereinafter simply referred to as the "LCD") 48, which
serves as an LCD monitor, such that the user can check the LCD 48
when the operation panel 42 is opened. The LCD 48 is used for
displaying information during a playback operation and for
displaying a screen input via a connecting terminal 51 of a
personal computer (PC) 51 which will be described below. In
addition, the LCD 48 is used also for displaying menu screens for
setting various modes of the information display apparatus 1. A
recess 45 is also formed on the controller/recorder main unit 41 so
that the user can place a finger when opening or closing the
operation panel 42.
At the right side of the controller/recorder main unit 41, as shown
in FIG. 6, a lid 52 that can be opened and closed with respect to
the controller/recorder main unit 41 via a hinge 46 is provided. By
allowing an engagement portion 52a of the lid 52 to engage with a
mating engagement portion 52b provided for the controller/recorder
main unit 41, the controller/recorder main unit 41 can remain
closed. When the lid 52 is opened, as shown in FIG. 6, the cable
connecting terminal 49 to be connected with the cable connecting
terminal 21 of the head-mounted unit 2 via the cable 3, an AV/S
connecting terminal 50 for connecting the controller/recorder 4
with a television set, and a PC connecting terminal 51 for
connecting the controller/recorder 4 with a personal computer (PC)
are exposed. In this manner, cords can be connected together at the
right side surface of the controller/recorder main unit 41 without
being extended from the other surfaces, thereby reducing a
troublesome operation for arranging the cords.
Also at the left side of the controller/recorder main unit 41, as
shown in FIG. 7, a lid 53 that can be opened and closed with
respect to the controller/recorder main unit 41 via a hinge 47 is
provided. By allowing an engagement portion 53a of the lid 53 to
engage with a mating engagement portion 53b provided for the
recorder/controller main unit 41, the controller/recorder main unit
41 can remain closed. When the lid 53 is opened, as shown in FIG.
7, a recording memory insertion slot 54 for inserting a recording
memory 120 (see FIG. 11), which serves as detachable recording
means, for example, a card memory, and a battery insertion slot 55
for detachably inserting batteries for supplying power are
exposed.
On the outer surface of the operation panel 42, as shown in FIG. 5,
a power switch 44 which is exposed even when the operation panel 42
is closed is provided. On the inner surface of the operation panel
42, various operation switches shown in FIG. 8 which are exposed
only when the operation panel 42 is opened are disposed.
More specifically, on the inner surface of the operation panel 42,
there are provided a speaker 56 for playing back sound, a switch 57
for increasing the volume of sound generated from the speaker 56, a
switch 58 for decreasing the volume, a playback start/stop switch
59 for starting or pausing playing back image information recorded
on the recording memory 120, a switch 61 for fast-forwarding and
searching images in the backward direction, a switch 62 for
fast-forwarding and searching images in the forward direction, a
menu button 63 for displaying menu screens for setting various
functions and dates concerning the information display apparatus 1
on the LCD 48, menu selection switches 66, 67, 68, and 69 for
moving an item to be selected or scrolling information displayed on
the menu screens in the top, bottom, left, and right directions,
and a setting switch 65 for setting the selected item.
The information display apparatus 1 of this embodiment, if the time
period when an image disappears from a frame for displaying the
image exceeds a predetermined time period Ts, is automatically set
to be in a low consumption power mode, and thereby, the consumption
of the whole of the information display apparatus 1 is reduced. The
predetermined time period Ts can be set by operating the menu
selection switches 66, 67, 68, and 69, as descried below.
The switches disposed on the operation panel 42 are switches mainly
for setting items of information which are not frequently
changed.
The external appearance and the overview of the remote controller 5
are described below with reference to the plan view of FIG. 10.
As stated above, switches which are relatively frequently changed
during a photographing operation are disposed on the remote
controller 5. The remote controller includes, as shown in FIG. 10,
a keyboard 71, a dome pointer operation portion 72, and an antenna
73.
The keyboard 71 is means for mainly inputting character-data. The
character-data input through the keyboard 71 can be displayed on
one or both of a see-through image display portion 6 (see FIG. 11)
and the LCD 48 in the controller/recorder 4. In addition, the
keyboard 71 contains a key which also functions as means for
scrolling displayed items and character information in the top,
bottom, left, and right directions.
The dome pointer operation portion 72 is scrolling means, and
contains a pointer 74, a left button 75, and a right button 76. The
pointer 74 is a pointing device which can move a mouse pointer,
e.g., by operating the pointer 74 with a finger. That is, this
operation of the pointer 74 corresponds to the operation of moving
a mouse, which is generally adopted for personal computers or the
like. Also, the left button 75 and the right button 76 correspond
to the left button and the right button of an ordinary mouse. Thus,
the mouse pointer is moved on a screen by operating the pointer 74,
and the left button 75 or the right button 76 is operated at a
desired location. This operation is equivalent to the movement and
clicking of the mouse.
The antenna 73 is transmitting means by which information input to
the remote controller 5 by the above-described operation is
transmitted to the controller/recorder 4. The controller/recorder 4
executes processing in accordance with the operation contents,
based on the information received from the remote controller 5.
FIG. 11 is a block diagram illustrating the configuration of,
mainly, an electronic circuit of the information display apparatus
1.
As stated above, the information display apparatus 1 includes the
head-mounted unit 2, the controller/recorder 4, and the remote
controller 5. The head-mounted unit 2 includes the see-through
image display portion 6 as a main electronic circuit. The
controller/recorder 4 and the see-through image display portion 6
are connected to each other through the cable 3. The
controller/recorder 4 and the remote controller 5 are wirelessly
connected to each other.
The controller/recorder 4 contains a memory 116, a D/A conversion
circuit 117, the LCD 48, an LCD driver 118, a
compression/decompression circuit 119, a selection circuit 121, the
recording memory 120, a hard disc 122, the speaker 56, a reception
circuit 123, a display memory 125, a character generator 126, a
first operation switch 113, an EEPROM 114, a power supply circuit
124, and a first CPU 111.
The memory 116 is first memory means which constitutes displaying
means, and is formed of, for example, a frame buffer for reading
information such as images and characters generated by the first
CPU 111, or information such as images and characters stored in the
recording memory 120 and the hard disc 122 and temporarily storing
the read signals.
The D/A conversion circuit 117 converts digital signals stored in
the memory 116 to analogue signals.
The LCD 48 is the same as that shown in FIG. 9, and displays an
image or other information, based on the analogue signals converted
through the D/A conversion circuit 117.
The LCD driver 118 controls and drives the LCD 48.
The compression/decompression circuit 119 comprises a compression
circuit portion and a decompression circuit portion. Digital
signals stored in the memory 116 are compressed in the compression
circuit portion. The digital signals read from the recording memory
120 and compressed are decompressed in the decompression circuit
portion.
The selection circuit 121 caries out two-way selection, that is,
decides the places which a signal is to be output from and is to be
input to. In this case, according to the two-way selection, any one
of the memory 116, the recording memory 120, the hard disc 122, and
the compression/decompression circuit 119 may be the place from
which a signal is output from and which a signal is input to. For
example, the selection circuit 121 selects one from the recording
memory 120, the hard disc 122, the memory 116, to which a digital
signal compressed in the compression/decompression circuit 119 is
to be output. In the case in which information stored in the
recording memory 120 or the hard disc 122 is read into the memory
116 and is regenerated and displayed, the selection circuit 121
selects a signal output from either the recording memory 120 or the
hard disc 122, based on a control signal from the first CPU 111 and
outputs to the compression/decompression circuit 119. Moreover, the
selection circuit 121 selects the data transfer from memory 116 to
the recording memory 120 or the hard disc 122, or the data transfer
from the recording memory 120 or the hard disc 122 to the memory
116 which is to be made via the compression/decompression circuit
119 or not. In the case in which the information is, e.g., image
information excluding character data (hereinafter, information
excluding character date is generally refereed to as image data),
the transfer is carried out after the compression or decompression
in the compression/decompression circuit 119. On the other hand, in
the case of character data, the transfer is carried out, not
through the compression/decompression circuit 119.
The recording memory 120 is formed of, for example, a detachable
memory card. The recording memory 120, when it is selected by the
selection circuit 121, stores digital signals compressed in the
compression/decompression circuit 119.
The hard disc 122 is contained in the controller/recorder 4. The
hard disc 122, when it is selected by the selection circuit 121,
stores digital signals compressed in the compression/decompression
circuit 119.
The speaker 56 (see FIG. 8) plays back sound, when an image is
regenerated with the sound or generates alarm sound, if necessary,
based on the control by the CPU 111.
The reception circuit 123 receives a signal wirelessly transmitted
from a transmission circuit 133 of the remote controller 5, which
will be described below.
The display memory 125 is second memory means which constitutes the
display means, and stores image data to be displayed on the
see-through image display portion 6. The display memory 125 is
formed of memory cells one-to-one corresponding to the display
pixels provided for LCD 104 in the see-through image display
portion 6 which will be described below.
The character generator 126 generates character data corresponding
to the key operation in the remote controller 5.
The first operation switch 113 is means which inputs for different
operations concerning the information display apparatus 1, and also
has functions of adjusting and time-setting. The first operation
switch 113 contains different switches as shown in FIG. 8.
The EEPROM 114 is third memory means which constitutes
display-controlling means, and stores different data used in the
information display apparatus 1. In the EEPROM 114, a mapping
coordination-relationship between original information stored in
the memory 116 and the memory cells of the display memory 125 are
stored as a table which will be described below.
The power supply circuit 124 is formed of, for example, detachable
batteries and supplies power to the controller/recorder 4, and also
supplies power to the see-through image display portion 6 of the
head-mounted unit 2 via the cable 3.
The first CPU 111 controls the respective circuits in the
controller/recorder 4, and also controls the see-through image
display portion 6 by communicating with a second CPU 112, which
will be described below, within the see-through image display
portion 6. The first CPU 111 is systematic control means in this
information display apparatus 1, and also functions as display
means, display control means, moving control means, and adjustment
means.
Hereinafter, the principal operation of the controller/recorder 4
will be described.
Information in the memory 116 is compressed in the compression
circuit portion of the compression/decompression circuit 119, and
then, is stored in the recording memory 120 or the hard disc
122.
By operating the menu button 63 of the first operation switch 113,
the menu selection switches 66, 67, 68, and 69, and a defining
switch 65, information stored in the recording memory 120 or the
hard disc 122 is selected. In the case in which the playback is
instructed by operating the playback start/stop switch 59, the
information stored in the recording memory 120 or the hard disc 122
is read and temporarily stored in the memory 116. In the case in
which the information stored in the recording memory 120 or the
hard disc 122 is image data, the information is decompressed in the
decompression circuit portion of the compression/decompression
circuit 119, and then is transferred to the memory 116. In the case
in which the information stored in the recording memory 120 or the
hard disc 122 is character data, the information is transferred
from the selection circuit 121 directly to the memory 116 not via
the compression/decompression circuit 119.
The information stored in the memory 116 is converted to analogue
signals in the D/A conversion circuit 117. Thereafter, the
information is displayed on the LCD 48, or is subjected to
predetermined mapping and displayed on LCD 104, described below, of
the see-through image display portion 6. When the information is
displayed on the LCD 48, the operation of the LCD 48 is controlled
by a signal generated from the LCD driver 118. On the other hand,
when the information is displayed on the LCD 104 of the see-through
image display portion 6, image data stored in the memory 116 is
mapped to the memory cells of the of the display memory 125,
referring to the table stored in the EEPROM 114. Thus, the image
data mapped and stored in the display memory 125 is output to the
LCD 104 of the see-through image display portion 6.
When keying-in operation is made through the keyboard 71 of the
remote controller 5, the character generator 126 generates
character data corresponding to the operation. The character data
is synthesized with predetermined image data by the first CPU 111,
is temporarily stored in the memory 116, and is displayed on the
LCD 48 or the LCD 104 of the see-through image display portion 6 as
described above.
The see-through image display portion 6 is display means by which
by which images and characters are projected to the eyes 99 of an
observer through a holographic optical element (hereinafter,
abbreviated to HOE) as a reflection combiner, and are displayed as
a virtual image on the front side in the visual field direction of
the observer. Moreover, the see-through image display portion 6
also functions as means for detecting a tilting angle in the yaw
and pitch directions of the head-mounted unit 2.
That is, the see-through image display portion 6 comprises an LED
driver 101, LED 102, a condenser lens 103, an LCD 104, an LCD
driver 105, a first HOE 106, a second HOE 107, an angular velocity
sensor 81, an angular velocity sensor 84, an amplifier 82, an
amplifier 85, an A/D converter 83, and a second CPU 112.
The LED driver 101 causes LED 102, described below, to emit light,
based on the control by the second CPU 112.
The LED 102 is a light-emission source, that is, is driven by the
LED driver 101 to emit light, and also is a component of the
display means.
The condenser lens 103 collects light emitted from the LED 102, and
is a component of the display means.
The LCD 104 is a display element formed of transmission type liquid
crystal for displaying information such as images or the like, and
is composed of a plurality of pixels, i.e., display picture
elements, two-dimensionally arranged. The LCD 104 is a component of
the display means, and is illuminated from the back side thereof
with light emitted from the LED 102 via the condenser lens 103.
The LCD driver 105 causes the LCD 104 to be driven and display
information such as images or the like, based on the control by the
second CPU 112, and constitutes a part of the moving control
means.
The HOE 106 is a reflective optical member for reflecting the
emitted light via the LCD 104 in the vertical downward direction
(see FIG. 16) while correcting for the aberration, which is
described below. The first HOE 106 constitutes the display
means.
The second HOE 107, which serves as a combiner, reflects and
diffracts the light from the first HOE 106 toward the observer's
eyes so that the information such as images and characters
displayed on the LCD 104 is projected and, thus, can be observed,
and also transmits external light toward the observer's eyes. The
second HOE 107 constitutes the display means.
The angular velocity sensor 81 constitutes angle detection means,
and detects the angle velocity in the yaw direction (see FIG. 13
described below) of the head-mounted unit 2.
The amplifier 82 amplifies output from the angular velocity sensor
81.
The angular velocity sensor 84 constitutes angle detection means,
and detects the angle velocity in the pitch direction (see FIG. 12
described below) of the head-mounted unit 2.
The amplifier 85 amplifies output from the angular velocity sensor
84.
The A/D converter 83 converts the output of the angular velocity
sensor 81 output via the amplifier 82 and the output of the angular
velocity sensor 84 output via the amplifier 85 to digital signals,
respectively, and outputs the signals to the second CPU 112.
The second CPU 112 comprises control means for mainly controlling
the see-through image display portion 6, and also functions as
display means, display control means, angle detection means, moving
control means, and adjustment means. In addition, the second CPU
112 functions as angle detection means for detecting the tilting
angle of the observer's head, based on the angular velocity
information output from the angular velocity sensors 81 and 84. The
second CPU 112 is connected to the first CPU 111 in a two-way
manner, and thus, executes a predetermined operation in mutual
communication and in cooperation with each other.
The remote controller 5 comprises a second operation switch 131, a
decoder 132, a transmission circuit 133, a power supply circuit
134.
The second operation switch 131, which serves as input means,
contains switches shown in FIG. 10, and also functions as
adjustment means and time-setting means.
The decoder 132 coverts an input operation from the second
operation switch 131 to a signal suitable for wireless
transmission.
The transmission circuit 133 wirelessly transmits the signal
converted by the decoder 132 to a reception circuit 123 of the
controller/recorder 4 via the antenna 73.
The power supply circuit 134 contains batteries or the like, and
provides power supplied for the respective circuits in the remote
controller 5.
Hereinafter, mainly, the optical configuration of the see-through
image display portion 6 is described with reference to FIGS. 12 to
18. FIG. 12 illustrates the pitch direction. FIG. 13 illustrates
the yaw direction. FIG. 14 illustrates the principle of the optical
system of the see-through image display portion 6. FIG. 15 is a
front view, partially in cross-section, illustrating an example of
the optical system of the see-through image display portion 6. FIG.
16 is a left side view illustrating an example of the configuration
of the optical system of the see-through image display portion 6.
FIG. 17 is a left side view illustrating another example of the
configuration of the optical system of the see-through image
display portion 6. FIG. 18 is a cross-sectional plan view
illustrating the configuration of the optical system of the
see-through image display portion 6.
In the see-through image display portion 6, image and character
information can be superimposed as a virtual image on a subject
which is substantially directly observed by the observer. Such a
display mode is referred to as the "see-through display". The term
"substantially directly observed" includes not only a case where
the observer observes the subject directly with his/her eyes, but
also a case where the observer observes the subject through a
generally planar transparent member formed of, for example, glass
or plastic, or a case where the observer observes the subject
through an eyesight-correcting lens.
First, terms concerning the tilting of the head will be described
below with reference with FIGS. 12 and 13. The term "pitch
direction" means "the tilting of the head in the front and back
direction" as shown in FIG. 12. The term "yaw direction" means "the
tilting of the head in the right and left direction" as shown in
FIG. 13. The head-mounted unit 2 is formed so as to be used while
it is put on the head of an observer. The detection of the tilting
of the head-mounted unit 2 has substantially the same meaning as
the detection of the tilting of the head of the head.
The principle of displaying see-through images by the optical
system of the see-through image display portion 6 (hereinafter
referred to as the "see-through image display optical system") in
this embodiment is described below with reference to FIG. 14.
Light emitted from the LED 102 is condensed by the condenser lens
103 and illuminates the LCD 104 from backward. The LED 102 contains
diodes capable of emitting light rays presenting three colors,
i.e., R (red), G (green), and B (blue) colors. In the case in which
character information is displayed, only the diode for G (green)
can be caused to emit, for example.
The second CPU 112 generates a signal corresponding to an image, a
character, or the like, and outputs it to the LCD driver 105. The
LCD driver 105 drives the LCD 104 based on the signal to allow the
LCD 104 to display the image and the character.
The image and the character output from the LCD 104 receiving light
from the LED 102 are reflected by the second HOE 107 and is guided
to the observer's eye. Then, the observer can observe the image and
the character as a virtual image VI. The first HOE 106 is not shown
since only the principle is illustrated in FIG. 14.
The second HOE 107 is a volume-phase holographic optical element
using a photosensitive material, such as photopolymer or
dichromated gelatin, and is designed to reflect light having R, G,
and B wavelengths emitted from the LED 102 with the maximum
reflectivity. Accordingly, when emitting G light to display a
character, the green character is clearly displayed as a virtual
image. When a color image is displayed so that it can be observed,
the color image is displayed on the LCD 104, and simultaneously,
the LED 102 is caused to emit three colors, i.e., R, G, and B type
of light. The HOE exhibits an excellent wavelength selectivity, and
more specifically, the HOE exhibits high reflection characteristics
for the R, G, and B wavelength light with extremely narrow
wavelength bands and exhibits high transmission characteristics for
the other wavelength light. Accordingly, external light having the
same wavelength range as the display light is diffracted and
reflected and does not reach the observer's eyes, but external
light having the other wavelength ranges reaches the observer's
eyes. Generally, since visible light has a wide wavelength
interval, an external image can be observed without any problem
even if light having very narrow wavelength intervals including the
R, G, and B wavelengths does not reach the observer's eye.
The first HOE 106 reflects light from the LCD 104 toward the second
HOE 107, and also has a function of correcting for the curvature of
field. Although in this embodiment the first HOE 106 is used, a
free-form optical element may be used. Although the free-form
optical element is light and small, it can correct for the
complicated aberration, and thus, clear images with small
aberration can be displayed without increasing the weight of the
head-mounted unit 2.
Specific arrangements of the see-through image display optical
system are described below with reference to FIGS. 15 to 18.
On the subject side in the portion inside the frame 13 and above
the transparent optical member 14 (and/or the transparent optical
member 15), the LED 102, the condenser lens 103, the LCD 104, and
the first HOE 106 are disposed in the order shown in FIG. 15. Those
elements are sandwiched between support frames 144 and 145 to be
fixed as shown in FIG. 18. In this case, the LED 102 is fixed by
the support frames 144 and 145 while being mounted on an electronic
circuit board 141. The first HOE 106 is tilted so that it can
reflect light from the LED 102 vertically downward.
The transparent optical member 14 (and/or the transparent optical
member 15) includes, as shown in FIGS. 16 and 17, optical waveguide
members 142 and 143 formed of transparent glass or plastic to have
a predetermined thickness and the second HOE 107 tilted between the
optical waveguide members 142 and 143 to reflect light backward.
With this configuration, light reflected by the first HOE 106
propagates inside the optical waveguide member 142 disposed above
the second HOE 107 and reaches the second HOE 107. The propagation
of light inside the optical waveguide member 142 may be only the
transmission, as shown in FIG. 16, or a combination of the
transmission and internal total reflection from the inner wall may
be employed as shown in FIG. 17. If the optical system is designed
to implement a combination of the transmission and the total
reflection, the transparent optical member 14 (and/or the
transparent optical member 15) can be thin-walled, thereby further
reducing the weight of the head-mounted unit 2.
On the observer's head side (opposite to the subject) in the inside
of the frame 13, an electric circuit substrate 146 having the LED
driver 101 and the LCD driver 105 mounted thereon is disposed on
the side opposite to the see-through image display optical system
in such a manner that the support frame 144 is sandwiched between
the substrate 146 and the optical system.
The see-through image display optical system includes the LED 102,
the condenser lens 103, the LCD 104, the first HOE 106, the second
HOE 107, and the optical waveguide members 142 and 143.
In general, the following two examples of the arrangement of the
see-through image display portion 6 may be presented since an
observer ordinarily observes a subject with his/or her eyes.
First, in the first example, such a see-through image display
optical system as shown in FIG. 15 forms a part of the see-through
image display portion 6 corresponding to one of both eyes, while a
transparent optical member having no see-through image-display
function forms the other part of the see-through image display
portion 6 corresponding to the other eye. In this case, desirably,
the transparent optical member for the other eye has the same
visual sensitivity transmission characteristic as the transparent
optical member 14 (and/or the transparent optical member 15).
Thereby, the fatigue of the eyes can be reduced even if the
information display apparatus is used for a long time-period.
In the second example, such a see-through image display optical
system as shown in FIG. 15 is formed in correspondence to each of
both eyes. In the case of a pair of the see-through image display
optical systems, the fatigue of the eyes can be further reduced. In
addition, an image can be stereoscopically displayed, if
necessary.
The structure for electrically connecting the electric equipment of
the front portion 11 and the electric equipment 30a of the temple
12 to each other will be described below, with reference to FIGS.
19 and 20. FIG. 19 is a plan view, partially in cross-section,
illustrating the structure of the joint portion containing the
front portion 11, a hinge portion 200, and the temple 12. FIG. 20
is a view illustrating the joint portion of the hinge 200 and the
temple 12, viewed from the left side substantially toward the right
side in FIG. 19.
In this case, the hinge portion 200 is defined as a portion,
containing the hinge 24, for connecting the temple 12 and the front
portion 11 (or the frame 13) to each other.
In this information display apparatus 1, as shown in FIG. 3, the
right and left temples 12 are positioned at a right angle to the
front portion 11 when the device is in use, and can be folded
toward the inner side to the front portion 11 with the hinges 24
and 25 as the rotational center. The hinge portion 200 containing
the hinge 24 on the right side and its neighborhood will be
described below. The hinge portion containing the hinge 25 on the
left side can be described in a similar manner.
The hinge 24 of the hinge portion 200 is formed as a knee-type
joint. As shown in FIG. 20, a U-shaped bearing 193 having a
cylindrical threaded hole 193a formed on the front portion 11 side,
and a bearing 194 having a cylindrical hole 194a formed on the
temple 12 side are combined with each other so that the holes 193a
and 194a communicate with each other. A shaft 191, which functions
as connecting pin, is inserted into the holes 193a and 194a. Thus,
the hinge 24 is formed. In FIG. 20, the portion of the hinge 24
belonging to the temple 12 is hatched with dotted lines.
As shown in FIG. 19, an electric circuit substrate 184 is provided
for the front portion 11. The electric circuit substrate 184 is
electrically connected to one end-side of a flexible printed
circuit substrate 185. The flexible printed circuit substrate 185
is disposed so as to range from the inside of the front portion 11
to the inside of the hinge portion 200. The other end-side of the
flexible printed circuit substrate 185 are electrically connected
to plural contacts 187, as shown in FIG. 20. These contacts 187 are
provided on a wall 195 formed upright in the hinge portion 200. The
connection between the flexible printed circuit substrate 185 and
the respective contacts 187 is performed via a connection portion
186.
Conductors 188 are formed on the bearing 194 on the temple 12 side
formed so as to be relatively rotated with respect to the bearing
193 on the front portion 11 side. The conductors 188 are coaxial
contacts positioned in an arch pattern on the outer periphery of
the bearing 194 and extending along the axial direction. The
conductors 188 correspond to the plurality of contacts 187, and are
embedded in an insulator. The exposed surfaces of the conductors
188 are plated with, e.g., gold. The overall surfaces of the
conductors 188 may be plated with gold.
With the above-described configuration, the contacts 187 and the
conductors 188 can be maintained in the electrically conducting
state, even if the front portion 11 and the temple 12 are
relatively rotated. It is not necessary to dispose a cable, a
printed circuit substrate, or the like for connection between
circuit portions such as the LED driver 101 and the LCD driver 105
concerning the projection of an image, and circuit portions
provided in the electric equipment 30a. Thus, the appearance is
simple and is kept in order. Particularly, the head-mounted unit 2
of the information display apparatus 1 is put on the head, when the
information display apparatus 1 is used. Thus, the appearance of
the head-mounted unit 2 is remarkable for others. Thus, the
above-described structure is very advantageous.
On the peripheral surface of the bearing 194, the contacts 187 are
electrically connected to one-end side of the flexible printed
circuit substrate 190 via the connection portion 189 on the
peripheral surface of the bearing 194. The other-end side of the
flexible printed circuit substrate 190 is connected to the electric
circuit substrate concerning the electric equipment 30a of the
temple 12 (not shown). Further, the other-end side is connected to
the controller/recorder 4 via the cable 3.
With this configuration, a signal for driving the LED driver 101
and the LCD driver 105 of the see-through image display portion 6
disposed in the frame 13 is transmitted, e.g., from the second CPU
112 disposed in the electric equipment 30a. In the case in which
the electric equipment 30b is provided with the angular velocity
sensors 81 and 84, the amplifiers 82 and 85, and the A/D converter
83, a detection signal output from these devices is transmitted to
the second CPU 112 of the electric equipment 30a via the front
portion 11 in a similar manner as described above.
Hereinafter, the display of an image, which is carried out by the
information display apparatus 1, is described with reference to
FIGS. 21 to 23. FIG. 21 illustrates an original image to be
displayed. FIG. 22 illustrates the coordination between the pixels
of LCD 104 and the original image. FIG. 23 illustrates the
coordination between the image as a virtual image formed by
projection of the original image and the original image.
It is assumed that an original image 151 to be displayed is one
shown in FIG. 21. To make clear the coordination between the
original image 151, the image displayed on the LCD 104, and the
image observed as a virtual image, the original image 151 is
appropriately divided into areas, and the areas are hatched. The
image areas hatched in the same pattern, shown in FIGS. 21 to 23,
corresponds to each other. The original image data is stored in the
memory 116.
In FIG. 21, one square corresponds to one of the pixels forming the
original image 151. In the case in which the original image 151 is
image data obtained, e.g., through an image capturing device, one
square corresponds to one pixel of the image capturing device. The
information of the respective pixels shown as the above-described
squares is stored in the memory 116.
In the original image 151 shown in FIG. 21, the center pixel area
of 6.times.6 is represented by area a. The area surrounding the
area a at an interval of one pixel, of which one side is composed
of ten pixels, and the width is one pixel, is represented by area
b. The area surrounding the area b at an interval of two pixels, of
which one side is composed of sixteen pixels, and the width is one
pixel, is represented by area c. The area surrounding the area c at
an interval of three pixels, of which one side is composed of
twenty four pixels, and the width is one pixel, is represented by
area d. Thus, the width between the areas becomes larger in the
order of from the center area a toward the peripheral area d.
FIG. 22 shows the display surface 152 of the LCD 104 as a display
element. In FIG. 22, one square on the display surface 152
represents one display-pixel. The display image data for the LCD
104 is stored in the display memory 125. In this case, data to be
displayed using display pixels is stored in the memory cells of the
display memory 125 in such a manner that one display pixel
corresponds to one memory cell. In this case, the display image
date stored in the display memory 125 is prepared, e.g., from the
original image data stored in the memory 116, by mapping with
looking up the table stored in the EEPROM 114, as follows. That is,
in the table stored in the EEPROM 114, there are preliminarily
stored the location in the LCD 104, shown in FIG. 22, to which the
pixel data at a location shown in FIG. 21 is to be mapped, that is,
the memory cell at the address in the display memory into which the
information stored at the respective addresses in the memory 116
having the original image data 151 stored therein is to be
mapped.
More specifically, the image data in the area a shown in FIG. 21 is
displayed in the central area a composed of 6.times.6 display
pixels of the LCD 104. Thus, regarding the image data in the area
a, a constant resolution can be kept in the horizontal/vertical
direction (the resolution of the original image). The image data in
the area b is displayed in the periphery of the area a, close to
the area a, that is, with no interval provided between the areas a
and b. However, one side of the area b displayed in this case is
composed of eight display-pixels. On the other hand, one side of
the area b of the original image 15 is composed of ten pixels.
Therefore, the mapping is suitably carried out looking up the table
in the EEPROM 114. The mapping is substantially diminished pixel
processing by which the ten pixels per one side are converted to
eight pixels per one side. Also, in the LCD 104, the area c is
arranged on the outside of the area b without no interval provided
between the areas b and c. Thus, one side of the area c is composed
of ten display pixels. Therefore, the area c is mapped in such a
manner that sixteen pixels per one side are diminished to ten
pixels per one side. Moreover, in the LCD 104, the area d is
arranged on the outside of the area c without no interval provided
between the area d and c. One side of the area d is composed of
twelve pixels. Thus, the area d is formed by mapping in such a
manner that twenty four pixels per one side are diminished to
twelve display pixels per one side.
When the display image shown in FIG. 22 is projected through the
see-through image display optical system, the image shown in FIG.
23 is observed as a virtual image 153 at a predetermined distance
and position. That is, the observed virtual image 153 has such that
he display image on the LCD 104 extends more and more in the
direction of from the center thereof toward periphery. In details,
the pixels of the virtual image 153 extends toward the periphery in
such a manner to have the same positional relationship (i.e., the
positional relationship of similarity) to the corresponding pixels
of the original image 151. Thus, the see-through image display
optical system is designed to cause the original image to extend
more and more in the peripheral direction and restore the
positional relationship between the pixels of the original image
151.
The resolution of the virtual image 153 shown in FIG. 23 decreases
more and more in the peripheral direction. This is designed in
conformity to the characteristic of a human being in which the
visual acuity rapidly decreases in the direction of from the center
of the retina toward the periphery thereof. Thus, no practical
problems occur, as far as an observer carefully sees the center of
the virtual image.
With the above-described configuration, the number of the display
pixels constituting the LCD 104 can be reduced, and thereby, the
size and the cost of the information display apparatus 1 can be
reduced.
As regards the relationship illustrated in FIGS. 21 and 22, the
display pixels shown in FIG. 22 are formed by removing some of the
pixels of the original image 151 shown in FIG. 21 (that is,
sampling). This is not restrictive. A display pixel may be formed
by calculation of plural pixel data of the original image 151 (that
is, interpolation). In the sampling using the removal of some
pixels, the load to the processing is relatively low. Thus,
advantageously, the processing can be performed at a high speed and
a low consumption power. On the other hand, in the case of the
calculation by interpolation, the image can be displayed more
accurately with respect to the original image 151.
FIGS. 24 to 26 illustrate other examples of the display of an image
carried out by the information display apparatus 1. FIG. 24
illustrates an original image to be displayed. FIG. 25 illustrates
the coordination between the pixels of the LCD 104 and the original
image. FIG. 26 illustrates the coordination between the image as a
virtual image formed by projection and the original image.
In the examples shown in FIGS. 21 to 23, the resolution is reduced
two-dimensionally in the direction of from the center of the screen
toward the periphery thereof, that is, in the vertical and
horizontal directions. On the other hand, in the examples of FIGS.
24 to 26, the resolution only in the vertical direction on the
screen is changed.
In the original image 151 shown in FIG. 24, each of the areas a, b,
c, and d has the same width in the horizontal direction as that of
the whole screen. In particular, the area a contains the central
portion of the original image 151, that is, is set so that six
pixels are arranged in the vertical direction as in the central
portion of the original image, and the same number of pixels as
that on the whole screen are arranged in the horizontal direction.
The areas b are set on the upper and lower sides of the area a with
an interval of one pixel provided between the areas a and b. Each
of the areas b is formed in a belt-shape in which the width in the
vertical direction is equal to one pixel, and the length in the
horizontal direction is the same as that of the whole screen. The
areas c are set on the upper and lower sides of the area b with an
interval of two pixels provided between the areas b and c. Each of
the areas c is formed in a belt-shape in which the width in the
vertical direction is equal to one pixel, and the length in the
horizontal direction is the same as that of the whole screen. The
areas d are set on the upper and lower sides of the area c with an
interval of three pixels provided between the areas c and d. Each
of the areas d is formed in a belt-shape in which the width in the
vertical direction is equal to one pixel, and the length in the
horizontal direction is the same as that of the whole screen. Thus,
the areas a, b, c, and d are formed in such a manner that the
interval between the areas becomes larger in the order of from the
area a, i.e., the central portion, to the areas d, the peripheral
portion in the perpendicular direction. Thus, in the example of
FIG. 24, the sampling is carried out in such a manner that the
resolution in the vertical direction is lowered toward the ends in
the vertical direction, while the resolution in the horizontal
direction is kept constant.
FIG. 25 shows the display surface 152 of the LCD 104 as a display
element.
The image data in the area a is displayed in the area a which is
the central portion of the LCD 104, and is composed of six pixels
in the vertical direction and the horizontal overall pixels in the
horizontal direction. Thus, for the image data in the area a, the
resolution is kept constant in both of the horizontal and vertical
directions (in particular, in the example of FIGS. 24 and 25, the
resolution of the original image in the vertical direction is kept,
but the resolution in the horizontal direction is reduced
corresponding to the relationship between the number of the
horizontal overall pixels of the original data and the number of
the horizontal overall pixels of the LCD 104). The image data in
the area b is displayed on the upper and lower sides of the image a
close to the area a, i.e., with no interval provided between the
images a and b. The image data in the areas c is displayed on the
LCD 104 on the outer sides of the areas b with no interval provided
between the images b and c. The areas d are arranged on the LCD 104
on the outer sides of the areas c with no interval provided between
the areas c and d. In this case, the mapping from the original
image 151 to the LCD 104 (that is, the mapping from the memory 116
to the memory cells of the display memory 125) is carried out
looking up the table in the EEPROM 114 as in the above-described
case.
The pixel configurations in the vertical and horizontal directions
of the LCD 104 are constant. On the other hand, the pixel
configurations in the vertical and horizontal directions of
original images to be displayed are different (for example, static
images, dynamic images, images with different resolutions,
vertically positioned images, horizontally positioned images, and
so forth). Thus, it is difficult to store table data for mapping
any type of original images in the EEPROM 114. Accordingly, only
the table data for mapping original images having such pixel
configurations as are generally used is stored in the EEPROM 114,
and for the other original images, the CPU 111 may be caused to
operate and map them. In the above-described system, typical data
can be processed at high speed to be displayed, and original image
data having such pixel configurations as not stored as the table
can be displayed in a desired manner.
FIG. 26 shows the image which is observed as a virtual image at a
predetermined distance and position, obtained when the display
image on the LCD 104 shown in FIG. 25 is projected through the
see-through image display optical system. Particularly, the
observed virtual image 153 extends more and more in the vertical
direction from the center toward the upper and lower peripheral
portions. Accordingly, the see-through image display optical system
causes an image to become larger and larger in the vertical
direction toward the peripheral portions thereof. In this case, the
virtual image 153 is extended in the vertical direction in such a
manner that the pixels of the virtual image 153 have the same
positional relationship (the positional relationship of similarity)
as the corresponding pixels of the original image 151, similarly to
the above-described case.
Accordingly, the resolution of the virtual image shown in FIG. 25
decreases more and more toward the peripheral portions in the
vertical direction, while the resolution in the horizontal
direction is kept constant.
In the case in which a configuration realizing the coordination
relationship between the pixel data shown in FIGS. 24 to 26 is
employed, image data can be easily mapped from the memory 116 to
the display memory 125 compared with the mapping in which the
resolution is changed in the two-directional direction, since with
the above-described configuration, the resolution of an image
observed by an observer is changed only in one-dimensional
direction.
In addition to the examples of FIGS. 21 to 23 and those of FIGS. 24
to 26, mapping in which the resolution is lowered corresponding to
only the distance from a predetermined position as a center (e.g.,
the central position of a display surface), irrespective of
directions starting from the center, in other words, the mapping in
which the resolution is lowered toward the concentric periphery
thereof can be carried out.
The examples of FIGS. 21 to 26 are presented for description of the
technical idea. Accordingly, the examples are different from the
practical configurations of an original image and the LCD 104 (that
is, the number of picture-elements or pixels practically employed
is higher, and also, for the original image, a variety of
pixel-configurations are used, as described above). Therefore, the
number of pixels and the sampling interval of an original image
have different values depending on the designs.
In the below-description, the mapping of an original image onto the
LCD 104 as a display element is referred to as first mapping, and
the process of displaying the image mapped to the LCD 104 by means
of the optical system is referred to as second mapping. In order
that the observed images shown in FIGS. 23 and 26 have shapes of
similarity to the original images shown in FIGS. 21 and 24, it is
necessary that the first and second mapping have a back-mapping
relationship to each other (strictly speaking, the back-mapping
relationship is impossible, since the irreversible change occurs in
which the number of pixels is reduced. Thus, the first and second
mapping is set in such a manner that the back-mapping is possible
with respect to the geometrical positional relationship). To assure
the relationship, it is more convenient to adjust the mapping by
programming in conformity to the characteristics of the optical
system rather than to determine the characteristics of the
above-described optical system in conformity to the above-described
mapping.
As described above, according to the present technique, the
original image is displayed on the display element in such a manner
that the resolution becomes lower and lower in the direction of
from the center to the periphery, and then, the image displayed on
the display element is displayed so as to be magnified more and
more toward the periphery through the optical system.
Hereinafter, the operation carried out when the information of the
original image stored in the memory 116 is mapped to the respective
addresses in the display memory 125 and displayed on the LCD 104
will be described.
The original image, which is an object to be displayed, is stored
in the memory 116 shown in FIG. 11. For example, it is assumed that
the original image is a high precision image. As described above,
there is preliminarily stored in the EEPROM 114 as the table which
coordinates between the data at each address in the memory 116 and
the address in the display memory 125 at which the data should be
written.
The memory addresses in the display memory 125 are coordinated with
the corresponding pixels in the LCD 104 in the one-to-one
relationship. The LCD 104 is driven by the LCD driver 105, so that
the data in the display memory 125 is displayed as an image.
In the above-described configuration, the first CPU 111 causes the
data in the memory 116 to be mapped to the respective addresses in
the display memory 125, looking up the table stored in the EEPROM
114.
The table stored in the EEPROM 114 realizes the back-mapping of the
mapping which is carried out by the see-through image display
optical system for projecting an image as a virtual image in such a
manner that the image is magnified more and more toward the
periphery thereof. Accordingly, the table can be calculated by
calculating the mapping based on the optical characteristics (the
optical characteristics may be ones defined by the design or ones
obtained by measuring each product considering the individual
difference or the like of the optical system), calculating the
back-mapping, and then processing for diminished pixel number.
The information mapped to the display memory 125 is displayed on
the LCD 104, and is reflected by the first HOE 106, and is guided
through the second HOE 107 as a combiner to the eyes 99 of an
observer.
Thereby, the observer can observe the image shown in FIG. 23 or 26
as a virtual image at a predetermined position.
The table stored in the EEPROM 114 is determined by the design as
described above. However, there is a possibility that different
manufacturing-errors occur during the process of producing the
information display apparatus 1. These errors are corrected by the
following means.
For the above-described correction, the image of a test chart as
shown in FIG. 27 is prepared as an original image and is stored in
the memory 116. FIG. 27 shows an example of the test chart. This
test chart 155 is formed by drawing straight lines in a
square-pattern in which, e.g., a plurality of straight lines are
arranged in the vertical and horizontal directions at the same
intervals, respectively.
The data of the test chart 155 stored in the memory 116 is mapped
to the display memory 125 looking up the table stored in the EEPROM
114.
The data stored in the display memory 125 is displayed on the
second LCD 112, and is projected through the see-through image
display optical system containing the first HOE 106 and the second
HOE 107 to the eyes of an observer as a virtual image of which the
peripheral portion is magnified. The observer can observe a figure
similar to the test chart 155 stored in the memory 116.
The image displayed via the second HOE 107 is photographed by an
image capturing device which is provided to acquire the correction
data for manufacture-correction. The image capturing device
eliminates the distortion of an image, or is such that the
information of the image distortion is known. Based on the image
data obtained by the image capturing device, information concerning
the geometrical distortion of the test chart 155 is analyzed and
acquired. The table in the EEPROM 114 is modified in such a manner
that the correction can be carried out based on the analytical
data. Desirably, the image data obtained by the image capturing
device is displayed on an adjustment monitor so that the displayed
image and the state in which the image is corrected can be
observed.
For example, it is assumed that a line which should be displayed as
a straight line in the horizontal direction (i.e., the line is a
line 157 obtained after the modification) is displayed as a curved
line 156 curved upward more and more toward the ends thereof as
shown in FIG. 28, for the eyes of an observer. FIG. 28 shows the
state of the straight line in the horizontal direction of the test
chart shown in FIG. 27 before and after it is corrected. The center
of the image is taken as an original point, and the x-axis and the
y-axis are set in the horizontal and vertical directions of the
test chart. A distortion .DELTA.y in the vertical direction occurs
at a position P(x, y) on the display image. Thus, the .DELTA.y is
determined. The table in the EEPROM 114 is corrected based on the
distortion .DELTA.y so that the image of the image P(x, y) can be
displayed on the corrected position Q. If the above-described
detection of the distortion .DELTA.y at a position P(x, y) is
carried out for all of the pixels constituting the image, it will
take much time to perform it. Therefore, the following method may
be made. That is, several portions within the image are set as
typical points, a distortion .DELTA.y at each typical point is
calculated, and for the other points, the distortion .DELTA.y is
estimated by interpolation or the like. Thus, the distortions
.DELTA.y for all of the pixels are determined. Then, the table in
the EEPROM 114 is modified so that the distortions .DELTA.y can be
corrected.
Also, such modification can be manually performed by checkers.
However, this is not practical considering the production
efficiency, the cost, and the individual difference of checkers,
and so forth. Thus, desirably, the inspection correction system in
which automatic measurement is carried out, and the table is
automatically modified is employed, as described above. In the case
in which an observer carries out the modification when uses the
information display apparatus 1, the observer may manually perform
the modification while he/she observes the image of the test chart
155 via the second HOE 107.
In the above-description, the distortion .DELTA.y in the vertical
direction is an object of the correction as shown in FIG. 28.
However, the object of the correction is not limited to the
above-described distortion. The object of the correction may be
different types of geometrical distortions such as ones in the
horizontal direction, the rotation direction, or the like.
Hereinafter, the information of an original image in the memory 116
is referred to as input information, the table information in the
EEPROM 114 as intermediate information, and the image observed as a
virtual image as output information. The above-described method of
modifying the table stored in the EEPROM 114 shows that the
intermediate information can be experimentally obtained based on
the relationship between the input information and the output
information. The characteristics of the intermediate information
are determined by the optical system. The above-described method of
experimentally determining the intermediate information does not
depend on the particular optical system. Accordingly, even if
another optical system is employed, the intermediate information
can be determined. Thus, the above-described method is not limited
to the optical system described in this embodiment, and can be
applied to various types, of optical systems, provided that the
optical systems are in conformity with the technical idea that the
peripheral image is magnified.
FIG. 29 is a flow chart illustrating the processing of adjusting
the initial position of a display screen. The processing
illustrated in FIG. 29 is described with reference to FIGS. 32 and
33. FIG. 32 illustrates a display example of a screen when the
initial position of the display screen is adjusted. FIG. 33
illustrates a display example of the screen of which the initial
position has been adjusted.
The information display apparatus 1 of this embodiment can display
a display-image as if the image were stationary with respect to the
external environment, irrespective of the movement of an observer's
head. Accordingly, when the observer tilts his/her head, the image
can be shifted in the direction opposite to the tilting, in an
amount corresponding to the tilting-degree. The processing
illustrated in FIG. 29 is the one for determining the tilting angle
of the head at which the above-described shifting is carried
out.
For example, it is assumed that when the observer faces just
forward, such a screen as shown in FIG. 32 is displayed. In FIG.
32, a range 91 capable of being displayed is shown by a dotted
line. A display frame 92 is displayed within the right and lower
part of the display-capable range 91. The inside of the display
frame 92 is a display screen 93.
In this state, the observer carries out predetermined keying-in
operation to set the information display apparatus 1 into the
adjustment mode, using the remote controller 5. Then, a character
94 "ADJ", representing the adjustment mode, is displayed in the
left part of the display-capable range 91 (step S1).
Subsequently, the pointer 74 of the remote controller 5 is moved in
the upper, lower, right, or left direction by keying-in, and then,
the first CPU 111 of the controller/recorder 4 wirelessly detects
the keying-in (step 2).
Then, when keying-in for moving the pointer 74 in the upper
direction is detected, the display frame 92 and the display screen
93 are moved at a predetermined movement velocity in the upper
direction within the display-capable range 91 while the keying-in
operation is being carried out (step 3).
When keying-in for moving the pointer 74 in the lower direction is
detected, the display frame 92 and the display screen 93 are moved
at a predetermined movement velocity in the lower direction within
the display-capable range 91 while the keying-in operation is being
carried out (step 4).
When keying-in for moving the pointer 74 in the left direction is
detected, the display frame 92 and the display screen 93 are moved
at a predetermined movement velocity in the left direction within
the display-capable range 91 while the keying-in operation is being
carried out (step 5).
When keying-in for moving the pointer 74 in the right direction is
detected, the display frame 92 and the display screen 93 are moved
at a predetermined movement velocity in the right direction within
the display-capable range 91 while the keying-in operation is being
carried out (step 6).
After one of the operations at steps S3 to S6 is completed, the
information display apparatus 1 waits for the left button 75 of the
remote controller 5 being clicked (step S7). Here, the processing
is returned to the step S2, and the keying-in is succeedingly
carried out until the left button 75 is clicked.
When the left button 75 is clicked, the clicking causes the
position of the display frame 92 to be defined. Simultaneously, the
character 94 "ADJ" representing the adjustment mode disappears.
Thereby, for example, the display frame 92 and the display screen
93 shown in FIG. 33 are displayed as virtual images.
Thereafter, the angular velocity data Oy and Op in the yaw and
pitch directions of the head, which were calculated based on the
outputs of the angular velocity sensors 81 and 84 are reset (step
S8). Thus, the adjustment of the position of the display screen is
completed.
By the above-described adjustment, the positions of the display
frame 92 and the display screen 93 in the initial state are
defined. Thereafter, the angular data .theta..sub.Y and
.theta..sub.P are measured using the initial state as a base
point.
In the examples of FIGS. 32 and 33, the display frame 92 is shown
by a boundary line. However, the display frame 92 is not
necessarily shown.
In the above case, the adjustment of the initial position is
performed by the processing illustrated in FIG. 29. This is not
restrictive. For example, when the head has a predetermined tilting
angle (specifically, when the head of an observer tilts at a
predetermined angle to be set as an initial position), a
predetermined keying-in operation (for example, the operation is
clicking the left button 75) may be executed. Thereby, the display
screen is set at a predetermined position, and the angular data
.theta..sub.Y and .theta..sub.P are reset. If the above-described
operation system is employed, the initial positions of the display
frame 92 and the display screen 93 can be adjusted more easily.
FIG. 30 is a flow chart illustrating the processing for controlling
the display position of an image.
According to the processing illustrated in FIG. 30, a display area
is shifted in the direction opposite to that of the tilting angle
of the head, so that the observer can observe a monitor as if it
were stationary with respect to the external environment.
There are no problems in the case in which, when the display area
of the monitor is shifted corresponding to the tilting angle of the
head, the display area can be changed smoothly at a high speed
corresponding to the change of the tilting angle of the head.
However, in practice, the speed of the change of the display area
has a limitation. Thus, the display area can not be smoothly
updated. Therefore, according to this embodiment, the display can
be updated only when the angle changes to a predetermined degree or
more so that the smoothness is not significantly deteriorated.
If the display area is updated with some lag every time the tilting
angle of the head finely changes, particularly, if the display area
is frequently updated, the observer feels that the movement is
wrong. Accordingly, in this embodiment, the threshold of the
head-tilting angle change when the head tilting angle changes in
the forward direction is made different from that when the head
tilting angle changed in the backward direction. That is, in
comparison with the angular change in the forward direction at
which the display area is updated, the angular change immediately
after the angular change in the backward is detected is set to be
larger. That is, a so-called hysteresis characteristic is provided,
so that the above-described feeling of the wrongness is reduced
(see steps S15 to S19 and step S22 which are described below).
Moreover, in this embodiment, when scrolling-operation is carried
out, the display area is updated in such a manner that the image in
the display area is scrolled (see steps S23 to 25 which will be
described below).
The above-described processing will be described in detail with
reference with FIG. 30.
The processing is started. First, the angular velocity information
in the yaw direction of the observer's head detected by the angular
velocity sensor 81 is input (step S11), and also, the angular
velocity information in the pitch direction of the observer's head
detected by the angular velocity sensor 84 is input (step S12).
The angular velocity in the yaw direction, acquired at the step 11,
is integrated with respect to the time. Thus, the angular change
.theta..sub.Y [rad] in the yaw direction is calculated (step S13).
Also, the angular velocity in the yaw direction, acquired at the
step 12, is integrated with respect to the time. Thus, the angular
change .theta..sub.p [rad] in the pitch direction is calculated
(step S14).
Subsequently, it is determined whether at least one of the absolute
value |.DELTA..theta..sub.Y| of the angular change in the yaw
direction within a predetermined time and the absolute value
|.DELTA..theta..sub.p| of the angular change in the pitch direction
within the predetermined time is larger than a predetermined value
.alpha.1 (predetermined first threshold) or not. That is, it is
determined whether at least one of
|.DELTA..theta..sub.Y|>.alpha.1 and
|.DELTA..theta..sub.P|>.alpha.1 is effective or not (step
S15).
In the case in which it is determined that at least one of
|.DELTA..theta..sub.Y| and |.DELTA..theta..sub.P| is larger than
the predetermined value .alpha.1, it is determined whether
|.DELTA..theta..sub.Y| or |.DELTA..theta..sub.P| determined to be
larger than the predetermined value .alpha.1 has a value
representing the opposite direction with respect to the preceding
detected value (that is, the sign of the value is opposite to that
of the preceding value or not) (step S16). This processing
determines whether the change of the tilting angle of the head is
still in the forward direction, or the direction of the tilting
angle change has turned to be opposite.
In the case in which it is determined that the value represents the
opposite direction at the step S16, it is determined whether at
least one of the absolute value |.DELTA..theta..sub.Y| of the
angular change in the yaw direction and the absolute value
|.DELTA..theta..sub.P| of the angular velocity in the pitch
direction is larger than a predetermined value .alpha.2
(predetermined second threshold) (the second predetermined value
.alpha.2 satisfies .alpha.2>.alpha.1) or not. That is, it is
determined whether at least one of
|.DELTA..theta..sub.Y|>.alpha.2 and
|.DELTA..theta..sub.P|>.alpha.2 is effective or not (step
S17).
In the case in which at least one of |.DELTA..theta..sub.Y| and
|.DELTA..theta..sub.P| is determined to be larger than the second
predetermined value .alpha.2 at the step S17, or in the case in
which the sign of the value does not represent the opposite
direction at the step 16, the movement amount of the display frame
92 (and the display screen 93) corresponding to the
.DELTA..theta..sub.Y or the .DELTA..theta..sub.P is calculated
(step S18). The calculation of the movement amount is calculated
according to L.times..DELTA..theta..sub.Y or
L.times..DELTA..theta..sub.P, in which L represents the distance
between the eye of an observer and the screen.
Subsequently, it is determined whether at least a part of the
display frame 92 after the movement is within the display-capable
range 91 or the whole of the display frame 92 gets to be out of the
display-capable range 91, based on the calculated movement (step
S19).
In the case in which the whole of the display frame 92 is
determined to get to be out of the display-capable range 91, it is
determined whether the time-period from the time when the whole of
the display frame 92 first moves out of the display-capable range
91, measured with a timer disposed on the inner side of the first
CPU 111 is not less than a predetermined time-period Ts stored in
the EEPROM 114 or not (step S20).
In the case in which the time-period is more than the predetermined
time-period Ts, the information display apparatus 1 is set in a low
consumption power mode, so that the power supplied from the power
supply circuit 124 is reduced (step S21). Then, this processing is
completed. The predetermined time-period Ts can be set at a desired
time-period by operation of the menu button 63, the menu selection
switches 66, 67, 68, and 69, and the defining switch 65 shown in
FIG. 8, as described above. Specifically, the low consumption power
mode is executed by stopping the operation of the first CPU 111 and
the second CPU 112, excluding the operation with respect to a part
of the functions thereof and by stopping the operation of the
blocks excluding the CPUs. This means is known. In the low
consumption power mode, the image of the display frame 92 is not
displayed, and only an image on the outside can be observed. The
information display apparatus 1 can be set in the low consumption
power mode at the step 21. Instead of this, the power supply of the
information display apparatus 1 may be turned off.
In the case in which it is determined that at least a part of the
display frame 92 is within the display-capable range 91, and an
image can be displayed at the step S19, or in the case in which the
time-period while the display frame 92 is in the "non-display"
state is shorter than the predetermined time-period Ts at the step
S20, the information of the display frame 92 and that of the
display screen 93 are mapped to the display memory 125 and stored
therein in such a manner that the display screen is moved in an
amount corresponding to the movement amount calculated at the step
S18, in the direction opposite to that of the angular change in the
yaw direction or the pitch direction of the observer's head (step
S22). Thereafter, the processing is returned to the step S11, and
the above-described processing is repeated.
In the case in which both of |.DELTA..theta..sub.Y| and
|.DELTA..theta..sub.P| are determined to be not more than the
.alpha.1 at the step S15, or both of the |.DELTA..theta..sub.y| and
|.DELTA..theta..sub.P| are determined to be not more than .alpha.2
at the step S17, it is determined whether the display screen 93
within the display frame 92 is scroll-operated or not (step S23).
The scroll-operation is executed by keying-operating the pointer 74
of the remote controller 5 so that it moves in the upper, lower,
right or left direction. While one of the keying-operations is
carried out, the display screen 93 is scrolled in a specified
direction corresponding to the keying-operation.
In the case in which it is detected that the scroll-operation is
carried out at the step S23, the original image is read from the
memory 116, mapped to, and stored in the corresponding positions of
the memory cells within the display frame 92 in the display memory
125, so that the display screen 93 is scrolled corresponding to the
scroll-operation (step S24).
Thereafter, it is determined whether the scroll-operation is
completed or not (step S25). The processing is returned to the step
S24, and the above-described processing is repeated until the
scroll-operation is completed.
In the case in which it is determined that the scroll-operation is
completed, or in the case in which it is determined that the
scroll-operation is not carried out at the step S23, the processing
is returned to the step S11, and the above-described processing is
repeated.
In the example described with reference to the flow chart of FIG.
30, the position of the display frame 92 is updated, following up
the change in tilting of the head, and thereby, the display frame
92 is displayed as if it were stationary with respect to the
external environment. This display gives a natural feeling. That
is, the display frame 92 seems to be as if it were a part of the
external environment. Thus, advantageously, the fatigue of the eyes
of an observer can be reduced. However, according to the processing
illustrated in FIG. 30, the display is sequentially updated,
following up the tilting of the head. Thus, the processing must be
carried out at a high speed. Thus, the power consumption increases.
FIG. 31 illustrates an example of the processing that takes account
of the above-described problems. According to the processing
illustrated in FIG. 31, the display frame 92 is displayed at a
constant position without the position of the display frame 92
being updated, when the tilting angle of the head is less than a
predetermined value. The display is caused to disappear, when the
tilting angle of the head is not less than the predetermined value.
According to this manner, advantageously, the configuration is
simple, and the consumption power is small, compared with the
processing described with reference to FIG. 30, although the
display gives somewhat an artificial feeling.
FIG. 31 is a flow chart of an example of the processing for
controlling the display/non-display of an image.
For a part of the processing illustrated in FIG. 31 which is
similar to the processing illustrated in FIG. 30, the description
is obviated, if it is appropriate. Thus, the description is made
only for the part thereof different from the processing of FIG.
30.
The processings at steps S31 to 37 illustrated in FIG. 31 are
similar to those illustrated in FIG. 30.
In the case in which at least one of |.DELTA..theta..sub.Y| and
|.DELTA..theta..sub.P| is determined to be larger than the second
predetermined value .alpha.2 at the step S37, or in the case in
which it is determined that the sign of the value does not
represent the opposite direction at the step S36, an accumulated
angle change-amount .SIGMA..DELTA..theta..sub.Y is calculated based
on the reset position of the .DELTA..theta..sub.Y, or an
accumulated angle change-amount .SIGMA..DELTA..theta..sub.P is
calculated based on the reset position of the .DELTA..theta..sub.P
(step S38). The calculation of the movement amount is made
according to L.times..SIGMA..DELTA..theta..sub.Y or
L.times..SIGMA..DELTA..theta..sub.P in which L represents the
distance between the eye of an observer and the screen.
Subsequently, it is determined whether at least one of the
calculated .SIGMA..DELTA..theta..sub.Y and
.SIGMA..DELTA..theta..sub.P is larger than a predetermined angle
.beta.1 (step S39).
In the case in which at least one of the accumulated angle
change-amounts is determined to be larger than the predetermined
angle .beta.1, the display of the display frame 92 and also an
image within the display frame 92 are caused to disappear (step
S40). The predetermined angle .beta.1 is set at a value at which it
can be determined that the display frame 92 gets to be out of the
display area in the case in which the display frame 92 is displayed
as if it were stationary with respect to the external environment,
as described in the example of FIG. 30. It is needless to say that
the display/non-display may be exchanged within an angular
change-range in which no artificial visual feeling is given.
After the display frame 92 and the image are caused to disappear
according to the processing at the step S40, it is determined
whether the time-period from the time when the display frame 92 and
the image are caused to disappear, measured by a timer disposed in
the first CPU 111, is not less than a predetermined time-period Ts,
or not (step S41).
In the case in which the time-period is determined to be more than
the predetermined time-period Ts at the step S41, the information
display apparatus 1 is set in the low consumption power mode, so
that the power supplied from the power supply circuit 124 is
reduced (step S42). Thereafter, this processing is completed. In
the low consumption power mode, images such as the display frame 92
and so forth are not displayed, and only external image can be
observed. As described above, the information display apparatus 1
is changed into the low consumption power mode at the step S42.
Instead of this, the power supply of the information display
apparatus 1 may be turned off.
In the case in which both of the calculated angle change-amounts
.SIGMA..DELTA..theta..sub.Y and .SIGMA..DELTA..theta..sub.P are
determined to be less than the predetermined angle .beta.1, or in
the case in which it is determined at the step S41 that the
time-period when the display frame 92 and an image are in the
"non-display" is less than the predetermined time-period Ts, the
information of the display frame 92 and that of the display screen
93 are mapped to the display memory 125, and the display of the
display frame 92 and an image within the display frame 92 at a
reset position are started (step S43). Thereafter, the processing
is returned to the step S31, and the above-described processing is
repeated.
The processing at steps S44 to S46 illustrated in FIG. 31 are
similar to the steps S23 to S25 illustrated in FIG. 30.
The processing described with reference to FIGS. 30 and 31 is
carried out mainly by the first CPU 111 (see FIG. 11). The
processing executed by the first CPU 111 may be distributed so that
the second CPU 112 carries out a part of the processing,
considering the load to the first CPU 111.
As described above, the date to be displayed on the LCD 104 is
prepared based on the original image stored in the memory 116.
Character data prepared by the character generator 126 and other
form data may be written directly in the display memory 125, not
via the memory 116. In this case, the data is written in the
display memory 125 after the data is processed corresponding to the
display position, looking up the table in the EEPROM 114, similarly
to the case of the original image stored in the memory 116.
On the contrary, it is possible that the data of the original image
read from the memory 116 is real-time processed and output from the
second CPU 112 synchronously with the display-control made by the
LCD driver 105 without the data of the original image being written
in the display memory 125.
With the above-described information display apparatus, the display
image of which the resolution is decreased more and more toward the
periphery thereof is projected to the eye of an observer while the
geometrical similarity to the original image can be kept
substantially constant as an example. However, this method is not
restrictive. The technique in which the resolution is reduced
toward the periphery may be applied to projector devices or the
like, by which an image is projected to a screen or the like.
According to this embodiment, the resolution of an image part
corresponding to the center of a retina in which the visual acuity
is set to be high, while that of an image part corresponding to the
periphery of the retina in which the visual acuity is set to be
low, considering the characteristics of human's eyes. Therefore, an
image can be observed as if the resolution of the whole image were
high. In this case, the number of pixels provided for the display
element, which has a limitation, are effectively used. Thereby, an
display element in which the number of pixels is smaller, and the
cost is relatively low can be used to obtain such a high-resolution
feeling as is comparable to that of a conventional display image.
If a display element comparable to a conventional one in the number
of pixels and the size is used, a much higher resolution-feeling
can be obtained.
In this case, the figure of the observed image is substantially
similar to that of the original image. Thus, the periphery of the
image is prevented from being compressed or decompressed, and thus,
the feeding of the observed image is natural.
The reduction of the resolution in the peripheral portion of the
image is performed by mapping the original image to the memory
cells. Therefore, the processing can be performed at a high speed,
and thus, the delay time till the image is displayed can be reduced
as much as possible. In this case, the coordination relationship is
stored as a table in the EEPROM, and thereby, the processing can be
performed at a high speed while a much load is not applied to the
CPU or the like.
One point on an image is set as a predetermined reference position.
Thereby, the pixels of the display element can be efficiently used,
and the resolution feeling can be enhanced.
Moreover, a straight line passing through one point on an image is
set as a predetermined reference position, and thereby, the mapping
processing can be performed simply and at a high speed.
The above-described configuration is particularly effective in a
head-mounted information display apparatus which is mounted on the
head of an observer and with which display information is projected
to the eye of the observer.
In addition, the information display apparatus is so configured
that the display information in the display area can be scrolled.
Therefore, desired information can be displayed in the part of the
display area to which a highest resolution is given. Thus, a
desired image can be clearly observed, although the device has a
small size and a light weight.
Furthermore, the image is moved in the direction opposite to the
tilting direction of the head of an observer, so that the position
of the virtual image observed by the observer is kept substantially
constant, irrespective of the tilting of the head of the observer.
Thus, the observer can observe an image as if the display screen
(e.g., having a large size) were stationary with respect to the
external environment.
Moreover, the initial position of the display image can be
adjusted. Thus, the optimum initial position can be selected,
depending on the individual difference and the use purpose of the
observer. For example, in the case in which the information display
apparatus is used as a monitor for a personal computer in a
tramcar, it is possible to set the display screen in the lower,
oblique direction and input characters from the remote controller.
The tilting angle of the head can be detected using the initial
position as a reference. Accordingly, an image taken from the
position of the head of the observer taking a natural pose as a
center can be observed. As the initial position of the display
screen is adjusted as described above, the display screen seems as
if it were set in the external environment at the optimum position
thereof. Thus, the above-described adjustment function is
convenient.
In the case in which the initial position of the image can be
caused to be moved to a desired position, the degree of freedom for
the adjustment is enhanced. In the case in which the initial
position is adjusted to a predetermined position, the operation can
be easily carried out.
In the case in which the tilting angle of the head is changed, and
the angle change-amount during a predetermined time-period is not
more than the first threshold, the display screen is not shifted in
the direction opposite to the change-direction of the angle of the
head. Thus, it is not necessary to calculate every time the
tilting-angle of the head finely changes. Thus, the load to the CPU
can be reduced.
Moreover, the threshold (second threshold) used to determine
whether the display screen is shifted in the direction opposite to
the change-direction of the angle of the head or not in the case in
which the tilting angle of the head changes in the opposite
direction is set to be larger than the threshold used in the case
in which the tilting angle changes in the same direction. This is
effective in preventing the display screen from flicking, which is
caused by the fine-vibration of the head occurring around a center
which is the predetermined position.
Moreover, a predetermined image is displayed so as to be
superimposed on the image of the external environment, and the
display state and the non-display state of the image are changed
over corresponding to the tilting angle of the head. In the case in
which the non-display state continues longer than a predetermined
time-period, the non-display state is succeedingly kept even after
the tilting angle of the head has a value corresponding to the
display-state. Thus, by the simple operation, that is, by changing
the angle of the head, observation of the image and that of the
external environment required for ordinary action can be easily
changed over while the information display apparatus is mounted to
the head. For example, in the case in which the information display
apparatus is used as a monitor for a personal computer in a tramcar
or the like, and the display screen is set to position in the lower
oblique part, the screen disappears from the visual field when the
user gets off the tramcar and the head is raised. Thus, the
external environment can be observed without being disturbed.
Accordingly, ordinary action can be taken with safety without the
information display apparatus being removed.
Moreover, when the non-display state continues for more than a
predetermined time-period, the power supply is turned off, or the
information display apparatus is set in the low consumption power
mode. Thus, the consumption power can be reduced, and the service
life of the battery can be saved, although the operation of
changing over the mode or turning off the power supply is not
intentionally carried out.
Thus, the information display apparatus, which is wearable and
portable, can be conveniently used, and can provide high grade
functions.
Moreover, the predetermined time-period until the information
display apparatus 1 is switched to the low consumption power mode
can be set at a desired value. Thus, the observer can use the
information display apparatus corresponding to his/her need.
[Appended Portions]
According to the foregoing embodiment of the present invention, the
following configurations can be implemented.
[Appended Portion A1]
An information display apparatus comprising:
display means for displaying an original image, which is a display
object, as display information in such a manner that the resolution
with respect to the original image is lowered as its position goes
away from a predetermined reference position; and
an optical system for guiding the display information in such a
manner that the display information can be observed substantially
in a figure geometically similar to the original information
excepting the reduction of the resolution.
[Appended Portion A2]
An information display apparatus according to Appended Portion A1,
wherein the apparatus comprises:
first storage means for storing the original image;
a display element having a plurality of pixels arranged at equal
intervals in the two-dimensional direction; and
display-control means for reading the original image from the first
storage means, controlling the assignment of the original
information to the pixels of the display element so that the
resolution is lowered as its position goes away from the reference
position, and causing the display element to display the image,
wherein the optical system guides the display information in such a
manner that the display information is more magnified as its
position goes away from the reference position while the
geometrical similarity to the original image can be substantially
kept.
[Appended Portion A3]
An information display apparatus according to Appended Portion A2,
wherein the display means further comprises second storage means
having memory cells one-to-one coordinating to the pixels of the
display element; and
the display-control means controls the assignment of the original
information to the pixels of the display element by mapping the
original information read from the first storage means to the
memory cells of the second storage means.
[Appended Portion A4]
An information display apparatus according to Appended Portion A3,
wherein the display-control means comprises third storage means for
storing, as a table, the mapping-coordination relationship between
the original information stored in the first storage means and the
memory cells of the second storage means.
[Appended Portion A5]
An information display apparatus according to Appended Portion A1,
wherein the predetermined reference position is one point within
the original image.
[Appended Portion A6]
An information display apparatus according to Appended Portion A1,
wherein the predetermined reference position is a straight line
passing through one point within the original image.
[Appended Portion A7]
An information display apparatus according to Appended Portion A1,
wherein the optical system guides the display information by
projecting the display information to the eye of an observer so
that the display information can be observed.
[Appended Portion A8]
An information display apparatus according to Appended Portion A7,
wherein the information display apparatus is such that it can be
mounted on an observer's head for use.
[Appended Portion A9]
An information display apparatus according to Appended Portion A1,
further comprising scroll means for scrolling the display
information.
[Appended Portion B1]
A head-mounted display apparatus comprising:
display means for projecting an image to an observer's eye to
observably display the image as a virtual image;
angle detection means for detecting the tilting angle of an
observer's head;
movement-control means for controlling so that the image to be
displayed by the display means is moved in an amount corresponding
to the angle detected by the angle detection means in the direction
opposite to the tilting direction of the observer's head, whereby
the position of the virtual image observed by the observer is kept
substantially constant, irrespective of the tilting of the
observer's head; and
adjustment means for adjusting the initial position of the image
displayed by the display means;
whereby the movement-control means detects the tilting angle of the
head, and controls the display position of the image displayed by
the display means, based on the tilting angle of the head detected
by the angle detection means, using the initial position of the
image as a reference.
[Appended Portion B2]
A head-mounted display apparatus according to Appended Portion B1,
wherein the adjustment means causes the movement-control means to
move the image to a desired position for adjustment of the initial
position of the image.
[Appended Portion B3]
A head-mounted display apparatus according to Appended Portion B1,
wherein the adjustment means adjusts the initial position of the
image to a predetermined initial position in advance.
[Appended Portion C1]
A head-mounted display apparatus comprising:
display means for projecting an image to an observer's eye to
observably display the image as a virtual image;
angle detection means for detecting the tilting angle of an
observer's head;
movement-control means for calculating the angle-change amount per
a predetermined time-period, based on the angle detected by the
angle detection means, and when the angle change-amount is not less
than a predetermined threshold, controlling so that the image to be
displayed by the display means in such a manner that the image is
moved in an amount corresponding to the angle detected by the angle
detection means in the direction opposite to the tilting direction
of the observer's head, whereby the position of the virtual image
observed by the observer is kept substantially constant,
irrespective of the tilting of the observer's head.
[Appended Portion C2]
A head-mounted display apparatus according to Appended Portion C1,
wherein the movement-control means controls so that the
predetermined threshold becomes larger in the case in which the
angle-change-direction of the head for a predetermined time-period
is opposite to the angle-change-direction of the head for the
predetermined time-period immediately before the above-described
predetermined time-period, compared with the case in which the
angle-change-directions are the same.
[Appended Portion D1]
A head-mounted display apparatus comprising;
display means for setting a display frame defining a display area
in which an image is displayed, in an image display-capable range,
and displaying the image within the display frame;
angle detection means for detecting the tilting angle of an
observer's head;
movement-control means controlling so that the display frame is
moved in such a manner that the frame is moved in an amount
corresponding to the angle detected by the angle detection means in
the direction opposite to the tilting direction of the observer's
head, whereby the position of the virtual image observed by the
observer is kept substantially constant, irrespective of the
tilting of the observer's head; and
control means for controlling the head-mounted display apparatus to
be automatically changed into a low consumption power mode in the
case in which the display frame departs from the display-capable
range, and is not displayed for not less than a predetermined
time-period.
[Appended Portion D2]
A head-mounted display apparatus according to Appended Portion D1,
further comprising time-set means for setting the predetermined
time-period at a desired value.
[Appended Portion D3]
A head-mounted display apparatus according to Appended Portion D1,
wherein the display means displays the image in such a manner that
the image is superimposed on an image of the external
environment.
[Appended Portion E1]
A head-mounted display apparatus comprising:
angle detection means for detecting the tilting angle of the head
of an observer;
display means for displaying a predetermined image in such a manner
that the image is superimposed on an image of the external
environment, the display means being changed from the display-state
of the image to the non-display-state thereof and vice-versa,
corresponding to the tilting angle of the observer's head detected
by the angle detection means; and
control means for controlling the display means in such a manner
that, in the case in which the non-display state of the display
means continues for not less than a predetermined time-period, the
non-display state is continuously kept, even if the tilting angle
of the head, thereafter, gets to have a value corresponding to the
display-state.
[Appended Portion E2]
A head-mounted display apparatus according to Appended Portion E1,
wherein the display means is changed so as to be in the display
state of the image when the tilting angle of the observer's head
detected by the angle detection means is within a predetermined
angle range and so as to be in the non-display state when the
tilting angle departs from the predetermined range.
[Appended Portion E3]
A head-mounted display apparatus according to Appended Portion E1,
wherein the display means displays the image in such a manner that
the image is moved in an amount corresponding to the angle detected
by the angle detection means in the direction opposite to the
tilting direction of the observer's head, whereby the relative
position of the image with respect to the external environment of
the image, observed by the observer, is kept substantially
constant, irrespective of the tilting of the observer's head.
[Appended Portion E4]
A head-mounted display apparatus according to any one of Appended
Portions E1 to E3, wherein the control means controls the
head-mounted display apparatus so that the power supply of the
head-mounted display apparatus is turned off or so that the
head-mounted display apparatus is set in a low consumption power
mode, when the non-display state of the display means continues for
not less than the predetermined time-period.
[Appended Portion E5]
A head-mounted display apparatus according to any one of Appended
Portions E1 to E4, further comprising time-set means for setting
the predetermined time-period at a desired value.
Having described the preferred embodiment of the invention
referring to the accompanying drawings, it should be understood
that the present invention is not limited to the precise embodiment
and various changes and modifications thereof could be made by one
skilled in the art without departing from the spirit or scope of
the invention as defined in the appended claims.
* * * * *