U.S. patent application number 15/867870 was filed with the patent office on 2018-05-17 for display apparatus having curved image forming apparatus.
This patent application is currently assigned to Sony Corporation. The applicant listed for this patent is Sony Corporation. Invention is credited to Shin Hasegawa, Yuichi Hasegawa, Eiichi Tanaka, Hirokazu Tatsuta.
Application Number | 20180136472 15/867870 |
Document ID | / |
Family ID | 52346006 |
Filed Date | 2018-05-17 |
United States Patent
Application |
20180136472 |
Kind Code |
A1 |
Tanaka; Eiichi ; et
al. |
May 17, 2018 |
DISPLAY APPARATUS HAVING CURVED IMAGE FORMING APPARATUS
Abstract
A display apparatus includes a frame, an image display apparatus
attached to the frame, and a distortion correction apparatus. The
image display apparatus includes an image forming apparatus and an
optical system configured to guide an image from the image forming
apparatus to a pupil of an observer. When it is assumed that a
direction, which corresponds to a first direction of the image, of
the image forming apparatus is an X-direction and a direction,
which corresponds to a second direction of the image which
direction is different from the first direction, of the image
forming apparatus is a Y-direction, the image forming apparatus is
curved in the X-direction and/or in the Y-direction. The distortion
correction apparatus corrects an input image signal to correct a
distortion of an image to be observed.
Inventors: |
Tanaka; Eiichi; (Chiba,
JP) ; Tatsuta; Hirokazu; (Kanagawa, JP) ;
Hasegawa; Shin; (Kanagawa, JP) ; Hasegawa;
Yuichi; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Sony Corporation |
Tokyo |
|
JP |
|
|
Assignee: |
Sony Corporation
Tokyo
JP
|
Family ID: |
52346006 |
Appl. No.: |
15/867870 |
Filed: |
January 11, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14655243 |
Jun 24, 2015 |
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PCT/JP2014/063034 |
May 16, 2014 |
|
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15867870 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G02B 2027/0159 20130101;
H04N 5/7491 20130101; G02B 27/02 20130101; G02B 27/0176 20130101;
G02B 2027/0147 20130101; G02B 27/0172 20130101; G02B 2027/0132
20130101; G06T 5/006 20130101; G02B 2027/015 20130101; H04N 5/64
20130101; G06T 5/00 20130101; G02B 27/017 20130101; G02B 2027/014
20130101; G02B 2027/011 20130101 |
International
Class: |
G02B 27/01 20060101
G02B027/01; G02B 27/02 20060101 G02B027/02; H04N 5/74 20060101
H04N005/74; G06T 5/00 20060101 G06T005/00; H04N 5/64 20060101
H04N005/64 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 16, 2013 |
JP |
2013147750 |
Claims
1. A display apparatus comprising: a frame; an image display
section attached to the frame; and a distortion correction section,
wherein the image display section includes an image forming unit
and wherein a direction, that corresponds to a first direction of
an image, of the image forming unit is an X-direction and a
direction, that corresponds to a second direction of the image
which direction is different from the first direction, of the image
forming unit is a Y-direction, and the image forming unit is curved
in the X-direction or the Y-direction, or in the X-direction and
the Y-direction.
2. The display apparatus according to claim 1, wherein the image
display section further includes an optical unit configured to
guide an image from the image forming unit to a pupil of an
observer.
3. The display apparatus according to claim 1, wherein the
distortion correction section corrects an input image signal to
correct a distortion of the image to be observed.
4. The display apparatus according to claim 1, wherein the
distortion correction section corrects an input image signal in
such a manner that a barrel distortion or a pincushion distortion
is applied to an input image signal to be corrected.
5. The display apparatus according to claim 1, wherein the
distortion correction section corrects, with respect to the input
image signal, at least an image signal corresponding to both ends
of the image forming unit and a part nearby to correct at least a
distortion of an image at both of the ends of the image forming
unit and the part nearby.
6. The display apparatus according to claim 2, wherein the optical
unit is arranged in such a manner that the image displayed on the
image forming unit reaches the pupil of the observer in a defocus
state.
7. The display apparatus according to claim 6, wherein resolution
in a horizontal direction of the image is made uniform by the
optical unit being arranged in such a manner that the image
displayed on the image forming unit reaches the pupil of the
observer in the defocus state.
8. The display apparatus according to claim 1, wherein the image
display section further includes a supporting member configured to
support the image forming unit, and a supporting surface of the
supporting member configured to support the image forming unit is
curved in the X-direction or the Y-direction, or in the X-direction
and the Y-direction, whereby the image forming unit is curved.
9. The display apparatus according to claim 8, wherein the
supporting member includes a pressing member, an outer shape of the
image forming unit is a rectangular shape, and an outer peripheral
part of the image forming unit which part is extended in the
X-direction is fixed to the supporting member by the pressing
member.
10. The display apparatus according to claim 8, wherein an outer
shape of the image forming unit is a rectangular shape, and an
outer peripheral part of the image forming unit which part is
extended in the X-direction is sandwiched by the supporting
member.
11. The display apparatus according to claim 2, wherein the image
display section includes an adjusting section configured to adjust
a distance between the image forming unit and the optical unit.
12. The display apparatus according to claim 11, further comprising
a display control section configured to control a size of a whole
image from the image forming unit according to the distance between
the image forming unit and the optical unit.
13. The display apparatus according to claim 2, wherein the image
display section includes an adjusting section configured to adjust
a distance between the optical unit and the pupil of the
observer.
14. The display apparatus according to claim 1, wherein when it is
assumed that an axis which passes through a predetermined point of
the image forming unit and which is parallel in the X-direction is
an X-axis and an axis which passes through a predetermined point of
the image forming unit and which is parallel in the Y-direction is
a Y-axis, the image display section further includes a rotation
section configured to rotate the image forming unit with at least
one of the X-axis, the Y-axis, and a Z-axis as a center.
15. The display apparatus according to claim 1, further comprising
a moving section configured to move the image forming unit in the
X-direction with respect to the optical unit.
16. The display apparatus according to claim 1, wherein an image
display section for a left eye and an image display section for a
right eye are attached to the frame, and each image display section
includes an image forming unit and an optical unit configured to
guide the image from the image forming unit to the pupil of the
observer.
17. The display apparatus according to claim 16, wherein each of
the optical units includes a reflecting mirror configured to
reflect the image from the image forming unit and a lens group
which is arranged between the pupil of the observer and the
reflecting mirror and into which the image reflected by the
reflecting mirror becomes incident, and a normal of the reflecting
mirror included in the optical unit of the image display section
for a left eye and a normal of the reflecting mirror included in
the optical unit of the image display section for a right eye
intersect with each other in a space on an opposite side of the
observer with respect to the reflecting mirrors.
18. The display apparatus according to claim 17, wherein the normal
of the reflecting mirror included in the optical unit of the image
display section for a left eye and the normal of the reflecting
mirror included in the optical unit of the image display section
for a right eye intersect with each other in a space lower than a
virtual plane including both pupils of the observer and an infinite
distance.
19. The display apparatus according to claim 17, wherein the image
forming unit is arranged in an upper part of the reflecting
mirror.
20. The display apparatus according to claim 1, wherein the image
forming unit includes an organic electro-luminescence display
section.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of and claims the benefit
under 35 U.S.C. .sctn. 120 of U.S. patent application Ser. No.
14/655,243, titled "DISPLAY APPARATUS HAVING CURVED IMAGE FORMING
APPARATUS," filed on Jun. 24, 2015, which claims the benefit under
35 U.S.C. .sctn. 371 as a U.S. National Stage Entry of
International Application No. PCT/JP2014/063034, filed in the
Japanese Patent Office as a Receiving Office on May 16, 2014, which
claims priority to Japanese Patent Application Number 2013-147750,
filed in the Japanese Patent Office on Jul. 16, 2013, each of which
is hereby incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present disclosure relates to a display apparatus. More
specifically, the present disclosure relates to a display apparatus
which can be used, for example, as a head mounted display
(HMD).
BACKGROUND ART
[0003] A virtual image display apparatus (display apparatus) to
make an observer observe a two-dimensional image, which is formed
by an image forming apparatus, as an enlarged virtual image with a
virtual image optical system has been known, for example, from
Japanese Patent Application Laid-Open No. 5-134208.
[0004] In the virtual image display apparatus disclosed in Japanese
Patent Application Laid-Open No. 5-134208, a liquid crystal display
unit is illuminated by light from a light source which light is
collimated by a lens through a polarizing plate and image light of
the illuminated liquid crystal display unit is collected at a first
focal point by a lens group. Then, the collected light is reflected
by a concave mirror, is collected at a second focal point on a
front surface of the lens of a pupil through the polarizing plate,
and reaches a retina. Accordingly, it is possible for a user to
observe an image.
CITATION LIST
Patent Document
[0005] Patent Document 1: Japanese Patent Application Laid-Open No.
5-134208
SUMMARY OF THE INVENTION
Problems to be Solved by the Invention
[0006] Incidentally, in the technique disclosed in Japanese Patent
Application Laid-Open No. 5-134208, since a plurality of optical
systems (lens, lens group, and concave mirror) is included, the
virtual image display apparatus is still large as a virtual image
display apparatus and is not adequate in a point of a compact size
and light weight. Also, there is a problem that a distortion of an
image which reaches an observer is caused or resolution of an image
does not become uniform.
[0007] Thus, a first purpose of the present disclosure is to
provide a display apparatus which includes an image forming
apparatus including a simple configuration and structure to realize
a large view angle with a compact size and light weight and in
which a distortion of an image to be observed by an observer is not
caused much. Also, a second purpose of the present disclosure is to
provide a display apparatus which includes an image forming
apparatus including a simple configuration and structure to realize
a large view angle with a compact size and light weight and which
can control a large difference or variation, which depends on an
angle of field, in resolution of an image to be observed by an
observer.
Solutions to Problems
[0008] A display apparatus according to a first mode of the present
disclosure which apparatus is for realizing the above first purpose
is a display apparatus including: (1) a frame; (2) an image display
apparatus attached to the frame; and (3) a distortion correction
apparatus, wherein the image display apparatus includes (A) an
image forming apparatus and (B) an optical system configured to
guide an image from the image forming apparatus to a pupil of an
observer, when it is assumed that a direction, which corresponds to
a first direction of the image, of the image forming apparatus is
an X-direction and a direction, which corresponds to a second
direction of the image which direction is different from the first
direction, of the image forming apparatus is a Y-direction, the
image forming apparatus is curved in the X-direction or the
Y-direction, or in the X-direction and the Y-direction, and the
distortion correction apparatus corrects an input image signal to
correct a distortion of the image to be observed. Note that the
first direction or the X-direction corresponds to a horizontal
direction of an image which reaches a pupil of an observer
eventually. The second direction or the Y-direction corresponds to
a vertical direction of the image which reaches the pupil of the
observer eventually. The X-direction and the Y-direction may be
orthogonal to each other or may not be orthogonal to each other. It
is also similar in the following description.
[0009] A display apparatus according to a second mode of the
present disclosure which apparatus is for realizing the above
second purpose is a display apparatus including:
[0010] (1) a frame; and
[0011] (2) an image display apparatus attached to the frame,
wherein the image display apparatus includes
[0012] (A) an image forming apparatus and
[0013] (B) an optical system configured to guide an image from the
image forming apparatus to a pupil of an observer,
[0014] when it is assumed that a direction, which corresponds to a
first direction of the image, of the image forming apparatus is an
X-direction and a direction, which corresponds to a second
direction of the image which direction is different from the first
direction, of the image forming apparatus is a Y-direction, the
image forming apparatus is curved in the X-direction or the
Y-direction, or in the X-direction and the Y-direction, and
[0015] the optical system is arranged in such a manner that the
image displayed on the image forming apparatus reaches the pupil of
the observer in a defocus state.
Effects of the Invention
[0016] In a display apparatus according to the first mode or the
second mode of the present disclosure, since an image forming
apparatus is curved, a difference between an optical path length of
light emitted from a center part of the image forming apparatus and
an optical path length of light emitted from an edge part in a
display region of the image forming apparatus can be reduced, for
example. Thus, a large view angle can be realized as well as a
compact size and light weight. Also, in the display apparatus
according to the first mode of the present disclosure, a distortion
correction apparatus is included. Thus, a distortion of an image to
be observed by an observer is not caused much. Also, in the display
apparatus according to the second mode of the present disclosure,
an optical system is arranged in such a manner that an image
displayed on the image forming apparatus reaches a pupil of an
observer in a defocus state. Thus, a difference or variation, which
depends on an angle of field, in resolution of an image to be
observed by an observer is not caused much. Note that an effect
described in the present description is just an example and is not
a limitation. There may be an additional effect.
BRIEF DESCRIPTION OF DRAWINGS
[0017] FIG. 1A, FIG. 1B, FIG. 1C, and FIG. 1D are conceptual
diagrams for describing how an image to be observed becomes, in a
display apparatus of a first embodiment, depending whether there is
distortion correction on an image signal.
[0018] FIG. 2A and FIG. 2B are charts illustrating results of
simulation of resolution in a horizontal direction of an image to
be observed by an observer when an optical system is arranged in
such a manner that an image displayed on an image forming apparatus
of a display apparatus of a fifth embodiment reaches a pupil of the
observer in a defocus state and a just-focus state.
[0019] FIG. 3 is a perspective view of a main part of a display
apparatus of when the observer wears the display apparatus.
[0020] FIG. 4 is a view in which a plane mirror or the like
included in an optical system of an image display apparatus for a
right eye is seen in an x-axis direction.
[0021] FIG. 5 is a conceptual diagram (perspective view) of an
image forming apparatus and an optical system which are seen from a
side of the observer.
[0022] FIG. 6 is a conceptual diagram (perspective view) of the
image forming apparatus and the optical system which are seen from
above.
[0023] FIG. 7A and FIG. 7B are respectively a perspective view of a
main part of the display apparatus of the first embodiment in which
view an observer wearing the display apparatus is seen from the
front and a perspective view of the main part of the display
apparatus in which view the observer wearing the display apparatus
is seen from a side.
[0024] FIG. 8A and FIG. 8B are, with respect to the display
apparatus of the first embodiment, respectively a perspective view
of an image forming apparatus and an optical system which are seen
in a direction toward the observer and a perspective view of the
image forming apparatus and the optical system which are seen from
the observer.
[0025] FIG. 9 is a conceptual diagram of a reflecting mirror or the
like which diagram is for describing an arrangement state of the
reflecting mirror included in the optical system.
[0026] FIG. 10A and FIG. 10B are, similarly to FIG. 9, conceptual
diagrams of the reflecting mirror or the like each of which
diagrams is for describing an arrangement state of the reflecting
mirror included in the optical system.
[0027] FIG. 11A is a schematic sectional view of a supporting
member and an image forming apparatus included in the display
apparatus of the first embodiment, FIG. 11B is a schematic
sectional view of the supporting member, and FIG. 11C is a
schematic plane view of the supporting member and the image forming
apparatus.
[0028] FIG. 12A and FIG. 12B are respectively a schematic sectional
view, along an arrow A'-A' in FIG. 11A, of the supporting member
and the image forming apparatus included in the display apparatus
of the first embodiment and a schematic sectional view, along an
arrow B'-B' in FIG. 11B, of the supporting member.
[0029] FIG. 13A is a schematic sectional view of a supporting
member and an image forming apparatus included in a display
apparatus of a second embodiment, FIG. 13B is a schematic sectional
view of the supporting member, FIG. 13C is a schematic plane view
of the supporting member and the image forming apparatus, and FIG.
13D is a schematic sectional view, along an arrow D-D in FIG. 13A,
of the supporting member and the image forming apparatus.
[0030] FIG. 14A is a schematic sectional view of a supporting
member and an image forming apparatus included in a display
apparatus of a third embodiment, FIG. 14B is a schematic plane view
of the supporting member and the image forming apparatus, and FIG.
14C is a schematic sectional view of a supporting member and an
image forming apparatus included in a modification of the display
apparatus of the third embodiment.
[0031] FIG. 15 is a perspective view of a part of the display
apparatus of the first embodiment.
[0032] FIG. 16A, FIG. 16B, FIG. 16C, and FIG. 16D are respectively
a bottom view, a top view, a right side view, and a rear view of
the display apparatus of the first embodiment.
[0033] FIG. 17A, FIG. 17B, and FIG. 17C are views illustrating how
images from the image forming apparatus are formed by various lens
groups.
[0034] FIG. 18 is a view conceptually illustrating a state to
adjust a distance between the image forming apparatus and the
optical system by an apparatus of adjusting a distance between an
image forming apparatus and an optical system.
[0035] FIG. 19A and FIG. 19B are schematic views of the apparatus
of adjusting a distance between an image forming apparatus and an
optical system.
MODE FOR CARRYING OUT THE INVENTION
[0036] In the following, the present disclosure will be described
based on embodiments with reference to the drawings. However, the
present disclosure is not limited to the embodiments. Various
numerical values or materials in the embodiments are examples. Note
that description will be made in the following order.
[0037] 1. General description of display apparatus according to
first mode and second mode of present disclosure
[0038] 2. First embodiment (display apparatus according to first
mode of present disclosure)
[0039] 3. Second embodiment (modification of first embodiment)
[0040] 4. Third embodiment (modification of second embodiment)
[0041] 5. Fourth embodiment (modification of first embodiment to
third embodiment)
[0042] 6. Fifth embodiment (display apparatus according to second
mode of present disclosure) and the like
[0043] [General Description of Display Apparatus According to the
First Mode and Second Mode of Present Disclosure]
[0044] In the following description, there is a case where the
display apparatus according to the first mode of the present
disclosure and the display apparatus according to the second mode
of the present disclosure are collectively referred to as a
"display apparatus and the like of the present disclosure".
[0045] In the display apparatus according to the first mode of the
present disclosure, the distortion correction apparatus is
configured to correct an input signal in such a manner that a
barrel distortion or pincushion distortion is applied to an input
image signal to be corrected. That is, in the image forming
apparatus, an image is displayed while a barrel distortion or
pincushion distortion is caused. Note that in a case where a lens
group included in an optical system has positive power, a
distortion as a characteristic of the lens group often becomes a
pincushion-type and a barrel distortion is preferably applied to an
image signal. On the other hand, in a case of negative power, a
distortion as a characteristic of the lens group often becomes a
barrel-type and a pincushion distortion is preferably applied to an
image signal. A distortion correction apparatus itself can include
a well-known circuit structure.
[0046] In the display apparatus according to the first mode of the
present disclosure which apparatus includes the above preferred
forms, the distortion correction apparatus corrects, with respect
to the input image signal, at least an image signal corresponding
to both ends of the image forming apparatus and a part nearby to
correct at least a distortion of an image at both of the ends of
the image forming apparatus and the part nearby.
[0047] In a case where the image forming apparatus is curved in an
X-direction, it is preferable that at least an image signal
corresponding to both ends in a Y-direction of the image forming
apparatus and a part nearby is corrected. Also, in a case where the
image forming apparatus is curved in the Y-direction, it is
preferable that at least an image signal corresponding to both ends
in the X-direction of the image forming apparatus and a part nearby
is corrected. In addition, in a case where the image forming
apparatus is curved in the X-direction and the Y-direction, it is
preferable that at least an image signal corresponding to both ends
in the X-direction and the Y-direction of the image forming
apparatus and a part nearby is corrected.
[0048] Also, in the display apparatus according to the second mode
of the present disclosure, an optical system is arranged in such a
manner that an image displayed on the image forming apparatus
reaches a pupil of an observer in a defocus state (non-focused
state). Thus, resolution in a horizontal direction of the image is
uniformed. In order to make an image, which is displayed on the
image forming apparatus, reach a pupil of an observer in a defocus
state, a distance (more specifically, distance between image
forming apparatus and lens group (described later) included in
optical system) between the image forming apparatus and the optical
system is controlled and optimized.
[0049] In the display apparatus and the like of the present
disclosure which apparatus and the like include the above-described
various preferred forms, the optical system includes a reflecting
mirror to reflect an image from the image forming apparatus and a
lens group which is arranged between a pupil of an observer and the
reflecting mirror and into which the image reflected by the
reflecting mirror becomes incident. In this case, the image forming
apparatus is arranged on an upper side of the reflecting
mirror.
[0050] In the display apparatus and the like of the present
disclosure which apparatus and the like include the above-described
various preferred forms, the image display apparatus further
includes a supporting member to support the image forming
apparatus. A supporting surface of the supporting member to support
the image forming apparatus is curved in the X-direction or the
Y-direction, or in the X-direction and the Y-direction. Thus, the
image forming apparatus is curved. In such a manner, since the
supporting member including the supporting surface curved in the
X-direction and/or the Y-direction is included, it is possible to
curve the image forming apparatus based on a simple configuration
and structure. Note that a display apparatus including such a
configuration is referred to as a "display apparatus of a first
configuration of the present disclosure" as a matter of
convenience.
[0051] Then, in the display apparatus of the first configuration of
the present disclosure, a degree of curvature in the X-direction of
the supporting surface of the supporting member can be larger than
a degree of curvature in the Y-direction thereof. That is, in a
case where the degree of curvature is expressed by an average
curvature radius, an average curvature radius in the X-direction of
the supporting surface of the supporting member can be smaller than
an average curvature radius in the Y-direction thereof. Moreover,
in the display apparatus of the first configuration of the present
disclosure which apparatus includes such a configuration, the
supporting member includes a pressing member. An outer shape of the
image forming apparatus is a rectangular shape and an outer
peripheral part of the image forming apparatus which part is
extended in the X-direction is fixed to the supporting member by
the pressing member. Note that the outer peripheral part of the
image forming apparatus indicates a region (so-called frame region)
between an end part of the image forming apparatus and an end part
of the display region of the image forming apparatus. It is also
similar in the following. Alternatively, an outer shape of the
image forming apparatus can be a rectangular shape and an outer
peripheral part of the image forming apparatus which part is
extended in the X-direction can be sandwiched by the supporting
member. However, these configurations are not the limitation. There
may be a case to fix the image forming apparatus to the supporting
member by using an adhesive. The supporting member can be made, for
example, from various kinds of plastic materials including an ABS
resin and the like, a composite material such as UNILATE
(registered trademark and is produced by UNITIKA LTD.) or FRP,
carbon fiber, a metal material such as aluminum, or an alloy
material.
[0052] Also, in the display apparatus and the like of the present
disclosure (including display apparatus of first configuration of
present disclosure) which apparatus and the like include the
above-described various preferred forms and configurations, the
image display apparatus can include an apparatus of adjusting a
distance between an image forming apparatus and an optical system
to adjust a distance between the image forming apparatus and the
optical system (specifically, reflecting mirror). Note that the
display apparatus including such a configuration is referred to as
a "display apparatus of a second configuration of the present
disclosure" as a matter of convenience. Here, since the apparatus
of adjusting a distance between an image forming apparatus and an
optical system is included, it becomes possible to deal with a
difference in eyesight of observers adequately and easily with a
simple configuration and structure, the difference being caused
depending on the observers. Then, in the display apparatus of the
second configuration of the present disclosure, a display control
apparatus to control a size of a whole image from the image forming
apparatus according to a distance between the image forming
apparatus and the optical system can be further included. With
respect to the distance between the image forming apparatus and the
optical system, a distance detection apparatus to detect the
distance between the image forming apparatus and the optical system
(specifically, reflecting mirror) is arranged in the apparatus of
adjusting a distance between an image forming apparatus and an
optical system. The distance detection apparatus only needs to be
an adequate apparatus depending on a configuration and structure of
the apparatus of adjusting a distance between an image forming
apparatus and an optical system. The control of a size of a whole
image can be a well-known control method such as performing
enlargement/reduction of the size of the whole image by performing
various kinds of signal processing (such as thinning processing or
interpolation processing) on an image signal used for forming an
image in the image forming apparatus.
[0053] Also, in the display apparatus and the like of the present
disclosure (including display apparatus of first configuration of
present disclosure and display apparatus of second configuration of
present disclosure) which apparatus and the like include the
above-described various preferred forms and configurations, the
image display apparatus can include an apparatus of adjusting a
distance between a pupil and an optical system to adjust a distance
between the optical system (specifically, reflecting mirror) and a
pupil of the observer. Note that the display apparatus including
such a configuration is referred to as a "display apparatus of a
third configuration of the present disclosure" as a matter of
convenience. Here, since the apparatus of adjusting a distance
between a pupil and an optical system is included, it becomes
possible to adjust and accommodate a distance between the pupil of
the observer and the lens group adequately and easily with a simple
configuration and structure.
[0054] Also, in the display apparatus and the like of the present
disclosure (including display apparatus of first configuration of
present disclosure, display apparatus of second configuration of
present disclosure, and display apparatus of third configuration of
present disclosure) which apparatus and the like include the
above-described various preferred forms and configurations, when it
is assumed that an axis which passes through a predetermined
position (such as collision point of an image forming apparatus and
optical axis which will be described later) of the image forming
apparatus and which is parallel in the X-direction is an X-axis and
an axis which passes through a predetermined point (such as
collision point of an image forming apparatus and optical axis) of
the image forming apparatus and which is parallel in the
Y-direction is a Y-axis, the image display apparatus further
includes a rotation apparatus to rotate the image forming apparatus
with at least one of the X-axis, the Y-axis, and a Z-axis as a
center. More specifically, there are a rotation apparatus to rotate
the image forming apparatus with the X-axis as a center, a rotation
apparatus to rotate the image forming apparatus with the Y-axis as
a center, a rotation apparatus to rotate the image forming
apparatus with the Z-axis as a center, a rotation apparatus to
rotate the image forming apparatus with the X-axis and the Y-axis
as a center, a rotation apparatus to rotate the image forming
apparatus with the X-axis and the Z-axis as a center, a rotation
apparatus to rotate the image forming apparatus with the Y-axis and
the Z-axis as a center, and a rotation apparatus to rotate the
image forming apparatus with the X-axis, the Y-axis, and the Z-axis
as a center. Moreover, in the display apparatus and the like of the
present disclosure (including display apparatus of first
configuration of present disclosure, display apparatus of second
configuration of present disclosure, and display apparatus of third
configuration of present disclosure) which apparatus and the like
include such a configuration and the above-preferred forms and
configurations, a moving apparatus to move the image forming
apparatus in the X-direction with respect to the optical system
(specifically, reflecting mirror) is further included.
[0055] Furthermore, in the display apparatus and the like of the
present disclosure (including display apparatus of first
configuration of present disclosure, display apparatus of second
configuration of present disclosure, and display apparatus of third
configuration of present disclosure) which apparatus and the like
include the above-described preferred forms and configurations, an
image display apparatus for a left eye and an image display
apparatus for a right eye are attached to a frame, and each image
display apparatus includes (A) an image forming apparatus and (B)
an optical system to guide an image from the image forming
apparatus to the pupil of the observer. Note that a display
apparatus including such a form is referred to as a "both-eyes-type
display apparatus of the present disclosure" as a matter of
convenience.
[0056] As described, in the both-eyes-type display apparatus of the
present disclosure, the optical system includes the reflecting
mirror to reflect an image from the image forming apparatus and a
lens group which is arranged between a pupil of the observer and
the reflecting mirror and into which the image reflected by the
reflecting mirror becomes incident. Also, a normal of the
reflecting mirror of the optical system image display apparatus for
a left eye and a normal of the reflecting mirror included in the
optical system of the image display apparatus for a right eye
intersect with each other in a space on an opposite side of the
observer with respect to the reflecting mirrors. By employing such
a form, it is possible to arrange the two image forming apparatuses
side by side easily with high flexibility in designing. In such a
form, the normal of the reflecting mirror included in the optical
system of the image display apparatus for a left eye and the normal
of the reflecting mirror included in the optical system of the
image display apparatus for a right eye intersect with each other
in a space lower than a virtual plane (xy plane described in the
following) including both pupils of the observer and an infinite
distance.
[0057] Then, in the above-described preferred configuration of the
both-eyes-type display apparatus of the present disclosure, as
illustrated in FIG. 9, FIG. 10A, and FIG. 10B, when it is assumed,
with respect to an arrangement state of the reflecting mirror, that
a virtual plane including both pupils of the observer and an
infinite distance is an xy plane, a straight line which connects
both of the pupils of the observer is an x-axis (specifically, axis
which is straight line to connect both pupils of observer from
pupil of right eye of observer to pupil of left eye thereof is
x-axis), an optical axis of a right eye of the observer is a y-axis
(specifically, axis which is orthogonal to x-axis and which moves
toward lens group side is y-axis), a point on the reflecting mirror
at which point an optical axis (main optical axis) of the lens
group included in the optical system of the image display apparatus
for a right eye collides with the reflecting mirror is a "collision
point of a reflecting mirror for a right eye and an optical axis",
and the reflecting mirror included in the optical system of the
image display apparatus for a right eye is arranged in parallel
with (at right angle with) an xz plane (see FIG. 9), and when it is
further assumed that an axis on the reflecting mirror which axis
passes through the collision point of a reflecting mirror for a
right eye and an optical axis and is in parallel with the xy plane
is a .xi.-axis and an axis on the reflecting mirror which axis
passes through the collision point of a reflecting mirror for a
right eye and an optical axis and is orthogonal to the .xi.-axis is
an .eta.-axis (see FIG. 9), a plane mirror included in the optical
system of the image display apparatus for a right eye is rotated
for an angle .theta..sub.1=45.degree..+-.5.degree. with the
.xi.-axis as a center and with an upper part of the plane mirror
being rotated in a direction away from the observer (see
dashed-dotted line in FIG. 10A for state of reflecting mirror and
axis before rotation and see solid line and dotted line in FIG. 10A
for state of reflecting mirror and axis after rotation) and is also
rotated for an angle .theta..sub.2=7.degree. to 21.degree. with the
.eta.-axis as a center and with a right end of the plane mirror
being rotated in the direction away from the observer (see
dashed-dotted line in FIG. 10B for reflecting mirror and axis
before rotation and see solid line and dotted line in FIG. 10B for
reflecting mirror and axis after rotation), and the image forming
apparatus and the optical system of the image display apparatus for
a left eye and the image forming apparatus and the optical system
of the image display apparatus for a right eye are arranged in a
mirror-symmetrical manner with respect to a virtual plane which
passes through a midpoint of a line segment to connect both of the
pupils of the observer and is in parallel with a yz plane.
Moreover, when it is assumed that an axis orthogonal to the
.xi.-axis and the .eta.-axis is a .xi.-axis, an example of a
relationship between an angle .theta..sub.3 and the angle
.theta..sub.1 and the angle .theta..sub.2 is indicated in the
following table 1, the angle .theta..sub.3 being formed between a
.xi.'-axis, which is an axis of when the .xi.-axis is projected on
the xy plane, and the y-axis. It is assumed that the angle
.theta..sub.3 in a (-x, y) quadrant is a positive value (see FIG. 9
and FIG. 10A). It is preferable that the optical axis (main optical
axis) of the lens group intersects with a center of the pupil of
the observer. Moreover, in the preferred forms and configurations,
as described above, it is preferable that the image forming
apparatus is arranged on an upper side of the reflecting
mirror.
TABLE-US-00001 TABLE 1 .theta.1 (degree) .theta.2 (degree) .theta.3
(degree) 45 5 9 45 10 15 45 15 22 45 18 25 45 20 29
[0058] Moreover, the both-eyes-type display apparatus of the
present disclosure which apparatus includes the above-described
preferred forms and configurations, an apparatus of adjusting a
distance between image display apparatuses to adjust a distance
between the image display apparatus for a left eye and the image
display apparatus for a right eye is further included. Since the
apparatus of adjusting a distance between image display apparatuses
is included, it becomes easy to deal with observers having
different distances between pupils.
[0059] In the display apparatus and the like of the present
disclosure (including display apparatus of first configuration of
present disclosure, display apparatus of second configuration of
present disclosure, display apparatus of third configuration of
present disclosure, and both-eyes-type display apparatus of present
disclosure, the following being in the similar manner) which
apparatus and the like include the above-described various
preferred forms and configurations, an outer shape of the image
forming apparatus is a rectangular shape and a wiring line is
extended to an external part from an outer peripheral part of the
image forming apparatus which part is extended in the Y-direction.
Here, an example of the wiring line includes a flexible printed
wiring board (FPC). A connection part provided to the outer
peripheral part of the image forming apparatus and the wiring line
are connected to each other by a well-known method.
[0060] Moreover, in the display apparatus and the like of the
present disclosure which apparatus and the like include the
above-described various preferred forms and configurations, one
lens group includes three lenses. The second lens includes negative
power. A refractive index of a material included in the second lens
is higher than a refractive index of a material included in each of
the first and the third lenses. Furthermore, the first lens and the
third lens include positive power. A meniscus lens is preferably
used as the second lens. The lens group is preferably a telecentric
optical system. More specifically, a side of the reflecting mirror
is preferably the telecentric optical system. Thus, even when a
distance between the image forming apparatus and the optical system
is adjusted by the apparatus of adjusting a distance between an
image forming apparatus and an optical system, variation in an
image which reaches a pupil of the observer can be controlled
securely.
[0061] Moreover, in the display apparatus and the like of the
present disclosure which apparatus and the like include the
above-described various preferred forms and configurations, the
image forming apparatus may be an image forming apparatus of any
type as long as the image forming apparatus has flexibility.
However, an organic electroluminescence display apparatus (organic
EL display apparatus) is preferably included. The organic EL
display apparatus itself can be an organic EL display apparatus
including a well-known configuration and structure.
[0062] Furthermore, in the display apparatus and the like of the
present disclosure which apparatus and the like include the
above-described various preferred forms and configurations, the
frame can be mounted on a head of the observer. However, such a
form is not the limitation. For example, the frame may be attached
to an arm extended from a ceiling or a wall or may be attached to a
movable robot arm. Also, a movement of a head of the observer may
be detected by a sensor and movement of the frame may follow the
movement of the head of the observer.
[0063] In a case where a frame is mounted on a head of an observer,
the frame can be any type as long as a configuration and structure,
in which mounting on the head of the observer and attachment of the
image display apparatus are possible, are included. For example, a
configuration including a front part arranged in front of the
observer and a side part extended from both ends of the front part
may be included. The image display apparatus is attached to the
frame. More specifically, for example, the image display apparatus
is attached to a holding member which is attached to a lower part
of the front part and is extended substantially in a horizontal
direction. Also, a forehead rest to contact with a forehead of an
observer is preferably attached to an upper part of the front part
in view of improvement in feeling of the observer with respect to
attachment of the image display apparatus.
[0064] Also, in the both-eyes-type display apparatus of the present
disclosure which apparatus includes the above-described preferred
forms and configurations, an example of an overlap (view angle of
both eyes) of a horizontal view in the image display apparatus for
a left eye and a horizontal view in the image display apparatus for
a right eye includes 45.degree. to 100.degree..
[0065] In the display apparatus and the like of the present
disclosure which apparatus and the like include the above-described
preferred forms and configurations, an example of a length L.sub.X
in the X-direction of a display region of the image forming
apparatus includes 83 mm to 130 mm. An example of the number of
pixels of the image forming apparatus includes 320.times.240,
432.times.240, 640.times.480, 1024.times.768, 1920.times.1080,
3840.times.2160 and the like. Also, an example of an aspect ratio
includes 21:9 and the like in addition to 4:3 and 16:9. An example
of a horizontal view angle (view angle of one eye) of the image
display apparatus includes 100.degree. to 120.degree..
[0066] Also, a point where an optical axis (main optical axis),
reflected by a reflecting mirror, of the lens group collides with
the image forming apparatus is assumed as a "collision point of an
image forming apparatus and an optical axis". A virtual plane in
contact with the collision point of an image forming apparatus and
an optical axis is assumed as an XY plane. An outer shape of the
display region of the image forming apparatus is assumed as a
rectangular shape. Also, it is assumed that the X-direction and the
Y-direction are orthogonal to each other. It is also assumed that
an axis which passes through the collision point of an image
forming apparatus and an optical axis and which is parallel in the
X-direction is an X-axis and an axis which passes through the
collision point of an image forming apparatus and an optical axis
and which is parallel in the Y-direction is a Y-axis. It is assumed
that an (X, Y, Z) coordinate of the collision point of an image
forming apparatus and an optical axis is (0, 0, 0). Accordingly, in
a case of X>0, a value of (dZ/dX).sub.Y=0 may be a positive
value [that is, when value of X is increased in case of Y=0, value
of Z may be increased monotonously]. In a case of Y=0 and when a
value of X is increased while a value of (dZ/dX).sub.Y=0 becomes an
arbitrary value, a value of Z may be increased eventually.
Similarly, in a case of Y>0, a value of (dZ/dY).sub.Y=0 may be a
positive value [that is, when value of Y is increased in case of
X=0, value of Z may be increased monotonously]. In a case of X=0
and when a value of Y is increased while a value of (dZ/dY).sub.X=0
becomes an arbitrary value, a value of Z may be increased
eventually. An example of a curved state of the image forming
apparatus includes a curved surface, a spherical surface, an
ellipsoid of revolution, a hyperboloid of revolution, and a
paraboloid of revolution which are expressed by aspherical-surface
functions. Alternatively, when a curved state of the image forming
apparatus is expressed by functions of Z.sub.X=f(X).sub.Y=0 and
Z.sub.Y=f(Y).sub.X=0, an example of these functions includes a
circle, an ellipsoid, a hyperbola, a parabola, an
aspherical-surface function, a polynomial of the third order or
more, a two-petalled rose, a three-petalled rose, a four-petalled
rose, a lemniscate, a limacon, a folium, a conchoid, a cissoid, a
bell curve, a tractrix, a catenary, a cycloid, a trochoid, an
asteroid, a parabola evolute, the Lissajous curve, the witch of
Agnesi, an epicycloid, a cardioid, a hypocycloid, a clothoid curve,
a clothoid curve, and a spiral. Alternatively, there is an example
in which the image forming apparatus is curved along a side surface
of a cylinder. When a degree of curvature of the image forming
apparatus is expressed by an average curvature radius, a value of
the average curvature radius may be fixed or may vary.
[0067] A display apparatus which includes image display apparatuses
respectively including image forming apparatuses having different
degrees of curvature may be prepared and an adequate display
apparatus may be provided according to eyesight of an observer.
Alternatively, a configuration and structure in which a degree of
curvature of an image forming apparatus can be varied may be
included. An example of a relationship between a radius of a side
surface of a cylinder, of when it is assumed that an image forming
apparatus is curved along the side surface of the cylinder, and a
diopter value will be indicated in the following table 2, but the
table is not the limitation.
TABLE-US-00002 TABLE 2 Diopter value Radius of side surface of
cylinder -3 59 mm -2 68 mm -1 80 mm 0 100 mm
First Embodiment
[0068] The first embodiment relates to a display apparatus
according to a first mode of the present disclosure. More
specifically, the first embodiment relates to a both-eyes-type
display apparatus of the present disclosure, a display apparatus of
a first configuration of the present disclosure, and a display
apparatus of a third configuration of the present disclosure. A
perspective view of a main part of a display apparatus of when an
observer wears the display apparatus is illustrated in FIG. 3. A
view of a plane mirror and the like included in an optical system
of an image display apparatus for a right eye which mirror and the
like is seen in an x-axis direction is illustrated in FIG. 4. A
conceptual diagram (perspective view) of an image forming apparatus
and an optical system which are seen from a side of the observer is
illustrated in FIG. 5. A conceptual diagram (perspective view) of
the image forming apparatus and the optical system which are seen
from above is illustrated in FIG. 6. Also, a perspective view of
the main part of the display apparatus of when the observer wearing
the display apparatus is seen from the front is illustrated in FIG.
7A. A perspective view of the main part of the display apparatus of
when the observer wearing the display apparatus is seen from a side
is illustrated in FIG. 7B. A perspective view of the image forming
apparatus and the optical system which are seen in a direction
toward the observer is illustrated in FIG. 8A. A perspective view
of the image forming apparatus and the optical system which are
seen from the observer is illustrated in FIG. 8B. Note that in the
drawings, there may be gradation in the image forming apparatus.
However, there is no special meaning in the gradation.
[0069] Moreover, schematic sectional views of a supporting member
and the image forming apparatus are illustrated in FIG. 11A and
FIG. 12A. Schematic sectional views of the supporting member are
illustrated in FIG. 11B and FIG. 12B. A schematic plane view of the
supporting member and the image forming apparatus is illustrated in
FIG. 11C. Note that FIG. 11A and FIG. 11B are schematic sectional
views along an arrow A-A in FIG. 11C. FIG. 12A and FIG. 12B are
schematic sectional views along an arrow A'-A' in FIG. 11A and an
arrow B'-B' in FIG. 11B. Also, a perspective view of a part of the
display apparatus of the first embodiment is illustrated in FIG.
15. In FIG. 15, a reflecting mirror, an image forming apparatus,
and the like are not illustrated. Moreover, a bottom view, a top
view, a right side view, and a rear view of the display apparatus
of the first embodiment are respectively illustrated in FIG. 16A,
FIG. 16B, FIG. 16C, and FIG. 16D. However, in order to simplify the
drawings, a part of components of the image forming apparatus or
the display apparatus is not illustrated.
[0070] A display apparatus of the first embodiment or a fifth
embodiment includes
[0071] (1) a frame 20 and
[0072] (2) an image display apparatus 30 attached to the frame 20.
The image display apparatuses 30 includes
[0073] (A) an image forming apparatus 40 and
[0074] (B) an optical system 50 to guide an image from the image
forming apparatus 40 to a pupil 11 of an observer 10. Also, the
display apparatus of the first embodiment further includes
[0075] (3) a distortion correction apparatus. Note that the display
apparatus of the first embodiment or the fifth embodiment which
will be described later is, more specifically, a both-eyes-type
display apparatus of the present disclosure in which an image
display apparatus for a left eye 30L and an image display apparatus
for a right eye 30R are attached to the frame 20.
[0076] Each of the image display apparatuses 30L and 30R
includes
[0077] (A) an image forming apparatuses 40L or 40R and
[0078] (B) the optical system 50 to guide an image from the image
forming apparatuses 40L or 40R to the pupil 11 (11L or 11R) of the
observer 10. The frame 20 in the display apparatus of the first
embodiment or the fifth embodiment which will be described later is
mounted on a head of the observer 10. More specifically, the
display apparatus of the first embodiment or the fifth embodiment
which will be described later is a head mounted display (HMD).
[0079] Here, when it is assumed that a direction of the image
forming apparatus 40 which direction corresponds to a first
direction (specifically, horizontal direction of image) of the
image is an X-direction and a direction of the image forming
apparatus 40 which direction corresponds to a second direction
(specifically, vertical direction of image), which is different
from the first direction, of the image is a Y-direction, the image
forming apparatus 40 is curved in the X-direction or the
Y-direction, or in the X-direction and the Y-direction. More
specifically, in the first embodiment or the fifth embodiment which
will be described later, the image forming apparatus 40 is curved
in the X-direction. Also, in the display apparatus of the first
embodiment or the fifth embodiment which will be described later,
the optical system 50 includes a reflecting mirror 51, which
reflects an image from the image forming apparatus 40, and a lens
group 52 which is arranged between the pupil 11 of the observer 10
and the reflecting mirror 51 and into which the image reflected by
the reflecting mirror 51 becomes incident. The image forming
apparatus 40 is arranged on an upper side of the reflecting mirror
51.
[0080] In the first embodiment, the image display apparatus 30
further includes a supporting member 60.sub.1 to support the image
forming apparatus 40. A supporting surface 61 of the supporting
member 60.sub.1 to support the image forming apparatus 40 is curved
in the X-direction or the Y-direction, or in the X-direction and
the Y-direction. More specifically, in the first embodiment, the
supporting surface 61 is curved in the X-direction. Then, the image
forming apparatus 40 is curved in the X-direction. More
specifically, the image forming apparatus 40 is curved along the
supporting surface 61 of the supporting member 60.sub.1. Note that
an outer shape of the image forming apparatus 40 and an outer shape
of the display region of the image forming apparatus 40 are
rectangular shapes. In such a manner, since the supporting member
60.sub.1 including the supporting surface 61 curved in the
X-direction and/or the Y-direction is included, it is possible to
curve the image forming apparatus 40 with a simple configuration
and structure.
[0081] More specifically, in the image display apparatus 30 of the
first embodiment, a degree of curvature in the X-direction of the
supporting surface 61 of the supporting member 60.sub.1 is larger
than a degree of curvature in the Y-direction thereof. That is, in
a case where the degree of curvature is expressed by an average
curvature radius, an average curvature radius in the X-direction of
the supporting surface 61 of the supporting member 60.sub.1 can be
smaller than an average curvature radius in the Y-direction
thereof. More specifically, a curvature radius in the X-direction
of the supporting surface of the supporting member is 100 mm and a
curvature radius in the Y-direction is infinity. Then, in the image
display apparatus 30 of the first embodiment, in a case of X>0,
a value of (dZ/dX).sub.Y=0 is a positive value. That is, in a case
of X>0 and Y=0 and when a value of X is increased, a value of Z
is increased monotonously. Also, (dZ/dY).sub.Y=0=0. More
specifically, the image forming apparatus 40 is curved along a side
surface of a cylinder and a radius of the side surface of the
cylinder is 100 mm. Also, as described later, an effective focal
length of the lens group 52 is 56 mm. Note that a preferred
relationship between the radius of the side surface of the cylinder
and the effective focal length of the lens group 52 will be
indicated in the following table 3.
TABLE-US-00003 TABLE 3 Radius of side surface Effective focal
length of cylinder (mm) of lens group 52 (mm) 50 28 100 56 146 67.2
238 95
[0082] Then, in the image display apparatus 30 of the first
embodiment, the supporting member 60.sub.1 includes a pressing
member 65. As described above, an outer shape of the image forming
apparatus 40 is a rectangular shape. An outer peripheral part of
the image forming apparatus 40 which part is extended in the
X-direction is fixed to the supporting member 60.sub.1 by the
pressing member 65.
[0083] More specifically, the supporting member 60.sub.1 and the
pressing member 65 are made from aluminum. A center part on an
upper surface of the supporting member 60.sub.1 corresponds to the
supporting surface 61 and outer peripheral parts 62A and 62B of the
supporting member 60.sub.1 which parts are extended in the
Y-direction are protruded compared to the supporting surface 61. A
part, which faces the supporting surface 61, of the outer
peripheral part 62A is a contact surface 62C. On the contact
surface 62C, one edge part of the image forming apparatus 40 which
part is extended in the Y-direction is butted. Also, a fixing
member 63 made from aluminum is fixed on the upper surface of the
supporting member 60.sub.1 by a screw 64, which is screwed into a
screw part 62D formed in the upper surface of the supporting member
60.sub.1, and is in touch with the other edge part of the image
forming apparatus 40 which part is extended in the Y-direction. In
the fixing member 63, a long hole through which the screw 64 passes
(long hole elongated in X-direction) is provided. Here, the image
forming apparatus 40 receives compression force in a direction of
an arrow "a" in FIG. 11A by the fixing member 63. Accordingly, the
image forming apparatus 40 is curved along the supporting surface
61 of the supporting member 60.sub.1 without a gap.
[0084] One end part 65A of the pressing member 65 presses the outer
peripheral part of the image forming apparatus 40 which part is
extended in the X-direction. The other end part 65B of the pressing
member 65 is engaged with a bottom surface of the supporting member
60.sub.1 extended in the X-direction. Accordingly, the outer
peripheral part of the image forming apparatus 40 which part is
extended in the X-direction is fixed to the supporting member
60.sub.1 by the pressing member 65.
[0085] Note that there may be a case where a lower surface of the
image forming apparatus 40 and the supporting surface 61 of the
supporting member 60.sub.1 are fixed by using an adhesive. In this
case, the pressing member 65 can be omitted.
[0086] Also, a wiring line 41, specifically, a flexible printed
wiring board (FPC) is extended to an external part from an outer
peripheral part of the image forming apparatus 40 which part is
extended in the Y-direction. A connection part provided in the
outer peripheral part of the image forming apparatus 40 and the
wiring line 41 are connected to each other by a well-known method.
In FIG. 11C, a state in which the wiring line 41 is extended from
one side of the outer peripheral part of the image forming
apparatus 40 which part is extended in the Y-direction is
illustrated. However, the wiring line 41 may be extended from both
sides of the outer peripheral part of the image forming apparatus
40 which part is extended in the Y-direction.
[0087] As described above, the optical system 50 includes the
reflecting mirror 51, which reflects an image from the image
forming apparatus 40, and the lens group 52 which is arranged
between the pupil 11 of the observer 10 and the reflecting mirror
51 and into which the image reflected by the reflecting mirror 51
becomes incident. Then, a normal NL.sub.L of the reflecting mirror
51 included in the optical system 50 of the image display apparatus
for a left eye 30L and a normal NL.sub.R of the reflecting mirror
51 included in the optical system 50 of the image display apparatus
for a right eye 30R intersect with each other in a space on an
opposite side of the observer 10 with respect to the reflecting
mirror 51 (see FIG. 3). Moreover, the normal NL.sub.L of the
reflecting mirror 51 included in the optical system 50 of the image
display apparatus for a left eye 30L and the normal NL.sub.R of the
reflecting mirror 51 included in the optical system 50 of the image
display apparatus for a right eye 30R intersect with each other in
a space lower than a virtual plane (xy plane) including both pupils
of the observer 10 and an infinite distance (see FIG. 3). Note that
in FIG. 3, the virtual plane including both of the pupils of the
observer 10 and the infinite distance is indicated by a reference
sign "HL". The image forming apparatus 40 is arranged on an upper
side of the reflecting mirror 51. An arrangement state of the
reflecting mirror 51 is illustrated in FIG. 9, FIG. 10A, and FIG.
10B. More specifically, in the first embodiment or the fifth
embodiment which will be described later, a length L.sub.X of the
display region of the image forming apparatus 40 is set as 100 mm.
Also, angles are set in the following manner:
[0088] an angle .theta..sub.1=45';
[0089] an angle .theta..sub.2=10.degree.; and
[0090] an angle .theta..sub.3=15.degree..
[0091] Note that in the embodiment, a collision point of a
reflecting mirror and an optical axis is included in the xy plane.
With such a setting condition, there is a gap of about 15 mm
between the image forming apparatus 40 included in the image
display apparatus for a left eye 30L and the image forming
apparatus 40 included in the image display apparatus for a right
eye 30R and the two image forming apparatuses can be arranged side
by side. Also, when the length L.sub.X of the display region of the
image forming apparatus 40 is 126 mm and the angles are in the
following manner:
[0092] the angle .theta..sub.1=45.degree.;
[0093] the angle .theta..sub.2=18.degree.; and
[0094] the angle .theta..sub.3=25.degree.,
[0095] there is a gap of about 15 mm between the image forming
apparatus 40 included in the image display apparatus for a left eye
30L and the image forming apparatus 40 included in the image
display apparatus for a right eye 30R and the two image forming
apparatuses can be arranged side by side.
[0096] In a case of
[0097] the angle .theta..sub.1=45.degree.,
[0098] the angle .theta..sub.2=0.degree., and
[0099] the angle .theta..sub.3=0.degree.
[0100] and when the length L.sub.X in the X-direction of the
display region of each image forming apparatus 40 is 100 mm and a
distance between an optical axis of a left eye of the observer and
an optical axis of a right eye thereof is 65 mm, the image forming
apparatus 40 included in the image display apparatus for a left eye
30L and the image forming apparatus 40 included in the image
display apparatus for a right eye 30R overlap with each other for
about 35 mm [=50+50-65 (mm)] and it is not possible to arrange the
two image forming apparatuses side by side.
[0101] In the display apparatus of the first embodiment or the
fifth embodiment which will be described later, the image forming
apparatus 40 specifically includes an organic electroluminescence
display apparatus (organic EL display apparatus) including a
well-known configuration and structure. Note that the organic EL
display apparatus includes a first substrate, a second substrate,
and a great number of light emitting parts sandwiched between the
first substrate and the second substrate. A thickness of the image
forming apparatus 40 is a thickness with which curvature along the
supporting surface of the supporting member 60.sub.1 without a gap
is possible. The thickness is, for example, 0.5 mm or thinner and
is, for example, 0.2 mm to 0.5 mm. Also, the number of pixels is
set as 1920.times.1080.
[0102] As illustrated in FIG. 15, FIG. 16A, FIG. 16B, FIG. 16C, and
FIG. 16D, in the display apparatus of the first embodiment or the
fifth embodiment which will be described later, the image display
apparatus for a left eye 30L and the image display apparatus for a
right eye 30R are included, as described above. A horizontal view
angle (view angle of one eye) in each image display apparatus 30 is
set as 100.degree.. An overlap (view angle of both eyes) of a
horizontal view in the image display apparatus for a left eye 30L
and a horizontal view in the image display apparatus for a right
eye 30R is set as 70.degree. and a whole horizontal view angle is
set as 130.degree.. The length L.sub.X in the X-direction of the
display region of each image forming apparatus 40 is set as 100 mm.
Also, a vertical view angle is set as 44.degree.. Note that when
mass of the lens group in this case is "1", mass of the lens group
becomes "4.6" and an effective focal length becomes 67.2 mm in a
case where the view angle of one eye is set as 120.degree., the
view angle of both eyes is set as 70.degree., the whole horizontal
view angle is set as 170.degree., and the length L.sub.X of the
display region of each image forming apparatus 40 is set as 126
mm.
[0103] The frame 20 mounted on a head of the observer 10 is made
from plastic and includes a front part 21 arranged in front of the
observer 10 and a side part 22 extended from both ends of the front
part. To a rear end part of the side part 22, a hole part 22A is
provided. By threading a belt through the hole part 22A and binding
a rear part of the head of the observer 10 with the belt, the frame
20 can be mounted on the head of the observer 10. An arm 23A is
extended upward from an upper part of the front part 21. To a
leading end part of the arm 23A, a forehead rest 23B to contact
with a forehead of the observer 10 is attached. In addition, a nose
pad part 24 is arranged on the front part
[0104] 21. Also, to a lower end part of the front part 21, a rear
part of a holding member 25 is attached and to a front part of the
holding member 25, a base part 26 is attached. Moreover, to a
leading end part of the base part 26, an apparatus of adjusting a
distance between a pupil and an optical system 80 which will be
described later is attached. A pedestal 71 included in the
apparatus of adjusting a distance between a pupil and an optical
system 80 is arranged on the base part 26 slidably in a front-rear
direction. An optical system 50L included in the image display
apparatus for a left eye 30L is housed in a chassis 53L. An optical
system 50R included in the image display apparatus for a right eye
30R is housed in a chassis 53R. To the chassis 53L, the image
display apparatus for a left eye 30L is attached. To the chassis
53R, the image display apparatus for a left eye 30R is attached.
The chassis 53L and the chassis 53R are attached to the pedestal
71. As described in the following, the optical system 50L and the
image display apparatus for a left eye 30L, and the optical system
50R and the image display apparatus for a right eye 30R are
independently and respectively arranged on the pedestal 71 slidably
in a right-left direction. Note that the "front-rear direction"
means a direction in which the lens group becomes close to or away
from the pupil and the "right-left direction" means a direction in
which the image display apparatus for a left eye and the image
display apparatus for a right eye become close to or away from each
other.
[0105] As described above, the optical system 50 includes the
reflecting mirror 51, which reflects an image from the image
forming apparatus 40, and the lens group 52 into which the image
reflected by the reflecting mirror 51 becomes incident. A
reflecting mirror 51R and a lens group 52R, which are included in
the image display apparatus for a right eye, are attached to the
pedestal 71 via the chassis 53R and are slidable on the base part
26 in the right-left direction. Similarly, a reflecting mirror 51L
and a lens group 52L, which are included in the image display
apparatus for a left eye, are attached to the pedestal 71 via the
chassis 53L and are slidable on the base part 26 in the right-left
direction. The lens group 52 (52R or 52L) is arranged between the
pupil 11 of the observer 10 and the reflecting mirror 51 (51R or
51L). The image forming apparatus 40 is arranged on an upper part
of the reflecting mirror 51.
[0106] One lens group 52 includes three lenses. The second lens has
negative power. A refractive index of a material included in the
second lens is higher than a refractive index of a material
included in each of the first and the third lenses. The first lens
and the third lens include positive power. Also, the second lens is
a meniscus lens. More specifically, an effective focal length of
the lens group 52 is set as 56.01 mm, a back focal length is set as
44.64 mm, a front focal length is set as -32.16 mm, and an F-number
is set as 14.0. A length in the horizontal direction of the lens
group 52 is set as 36 mm and a length in the vertical direction
thereof is set as 20 mm. Specifications of the first lens (lens
closest to pupil), the second lens, and the third lens (lens
closest to reflecting mirror) will be indicated in the following
table 4 but these specifications are not the limitation. The lens
group 52 is a telecentric optical system. More specifically, a side
of the reflecting mirror is the telecentric optical system. A
distance between the first lens and the pupil (pupil diameter: 4
mm) of the observer 10 is set as 10 mm. Note that when mass of the
lens group is set as "1", mass of a lens group in which a distance
between the first lens and the pupil of the observer 10 is 12 mm
becomes "1.7".
TABLE-US-00004 TABLE 4 First lens Second lens Third lens Refractive
index 1.740 2.017 1.740 Abbe number 44.8438 20.830 44.8438
Effective focal length 27.392 mm -43.604 mm 150.185 mm Back focal
length 28.101 mm -45.387 mm 146.790 mm Front focal length -11.141
mm 52.856 mm -124.868 mm F-number 6.8480 -10.9010 37.5463
[0107] How an image from the image forming apparatus 40 is formed
by various lens groups is illustrated in FIG. 17A, FIG. 17B, and
FIG. 17C. A lens group illustrated in FIG. 17A is a lens group of a
telecentric optical system. In FIG. 17B, a lens group including a
configuration close to that of the telecentric optical system is
illustrated. In FIG. 17C, a general lens group is illustrated. In
the first embodiment or the fifth embodiment which will be
described later, the lens group illustrated in FIG. 17A is
used.
[0108] In the display apparatus of the first embodiment or the
fifth embodiment which will be described later, an apparatus of
adjusting a distance between image display apparatuses 70 to adjust
a distance between the image display apparatus for a left eye 30L
and the image display apparatus for a right eye 30R is further
included. The apparatus of adjusting a distance between image
display apparatuses 70 specifically includes the pedestal 71, a
feed screw mechanism 73 attached to a side surface 72 placed on an
outer side of the pedestal 71, a tap hole 75A to fix the chassis 53
slidably to the pedestal 71 from a lower part, guide grooves 74B
and 76B provided to the chassis 53, a guide groove 75B provided to
the pedestal 71, and pins 74A and 76A which are provided to the
pedestal 71 and which are to be engaged with the guide grooves 74B
and 76B. Note that the guide grooves 75B, 75B, and 76B are extended
in the right-left direction. When the feed screw mechanism 73 is
rotated, the chassis 53 (chassis 53L or chassis 53R) moves in the
right-left direction with respect to the base part 26. The movement
of the chassis 53 is performed securely in the right-left direction
by engagement of the pin 74A, the tap hole 75A, and the pin 76A
with the guide grooves 74B, 75B, and 76B. A distance of the
movement of the chassis 53L and 53R in the horizontal direction is
set as .+-.5 mm. In such a manner, since the apparatus of adjusting
a distance between image display apparatuses 70 is included, it
becomes easy to deal with observers having different distances
between pupils. Instead of the feed screw mechanism 73, a
combination of a latch mechanism and a knob, that is, a rack and
pinion mechanism can also be used. The chassis 53R and 53L are
extended further upward compared to what is illustrated in FIG.
16A, FIG. 16B, FIG. 16C, and FIG. 16D. To each of the parts, which
are extended upward, of the chassis 53R and 53L, the supporting
member 60.sub.1 or the like which supports the image forming
apparatus 40 is attached but is not illustrated.
[0109] In the display apparatus of the first embodiment or the
fifth embodiment which will be described later, the apparatus of
adjusting a distance between a pupil and an optical system 80 to
adjust a distance between the pupil of the observer 10 and the
optical system 50 (specifically, lens group 52) is further
included. The apparatus of adjusting a distance between a pupil and
an optical system 80 specifically adjusts the distance between the
lens group 52 and the pupil of the observer 10. The apparatus of
adjusting a distance between a pupil and an optical system 80
specifically includes a side wall 82 attached to a leading end part
of a second holding member 26, a feed screw mechanism 83 attached
to the side wall 82, a key 27A which is provided to the pedestal 71
and is extended downward from the pedestal 71, a guide groove 27B
which is provided to the base part 26 and is engaged with the key
27A, and a fastening member 27C to hold the pedestal 71 slidably
with respect to the base part 26. When the feed screw mechanism 83
is rotated, the pedestal 71 moves in the front-rear direction with
respect to the base part 26. The movement of the pedestal 71 is
performed securely in the front-rear direction by engagement of the
key 27A with the guide groove 27B. A distance of the movement of
the pedestal 71 in the front-rear direction is set as .+-.4 mm. In
such a manner, since the apparatus of adjusting a distance between
a pupil and an optical system 80 is included, it becomes easy to
deal with observers having different distances between the pupil
and the lens group. Thus, it is possible to provide a display
apparatus capable of adjusting and accommodating a distance between
a pupil of an observer and a lens group adequately and easily with
a simple configuration and structure. Instead of the feed screw
mechanism 83, a combination of a latch mechanism and a knob, that
is, a rack and pinion mechanism can also be used.
[0110] Then, in the first embodiment, the distortion correction
apparatus corrects an input image signal to correct a distortion of
an image to be observed. Note that the distortion correction
apparatus corrects an input image signal in such a manner that a
barrel distortion or pincushion distortion is applied to an input
image signal to be corrected. That is, in the image forming
apparatus 40, an image is displayed while a barrel distortion or a
pincushion distortion is caused. Specifically, the distortion
correction apparatus corrects, with respect to the input image
signal, at least an image signal corresponding to both ends of the
image forming apparatus 40 and a part nearby to correct at least a
distortion of an image at both of the ends of the image forming
apparatus 40 and the part nearby. More specifically, in the first
embodiment, an image signal corresponding to a whole screen of the
image forming apparatus is corrected. Here, the distortion
correction apparatus itself can include a well-known circuit
configuration and is included in a control apparatus (not
illustrated) to control an operation of the display apparatus.
[0111] The distortion correction apparatus includes a distortion
correction coefficient table. In the distortion correction
coefficient table, a relationship between a position (X.sub.out,
Y.sub.out) of an output image signal in the image forming apparatus
and a position correction quantity (.DELTA.X.sub.out,
.DELTA.Y.sub.out) with respect to this position (X.sub.out,
Y.sub.out) is tabulated. Then, the distortion correction apparatus
calculates a correspondence relationship between a position on the
image forming apparatus and an output image signal. Then, referring
to the distortion correction coefficient table from a calculated
position (X.sub.out, Y.sub.out) in the image forming apparatus, the
distortion correction apparatus calculates a position correction
quantity (.DELTA.X.sub.out, .DELTA.Y.sub.out) with respect to the
position (X.sub.out, Y.sub.out). Then, from an input image signal,
a value of an image signal corresponding to a corrected position
(X.sub.out+.DELTA.X.sub.out, Y.sub.out+.DELTA.Y.sub.out) is
calculated by extraction or interpolation and is displayed as a
value of the position (X.sub.out, Y.sub.out) in the image forming
apparatus. The position correction quantity (.DELTA.X.sub.out,
.DELTA.X.sub.out) is calculated by various kinds of simulation,
experimentation, or the like.
[0112] Conceptual diagrams for describing how an image to be
observed becomes in the display apparatus of the first embodiment
depending on whether there is distortion correction (correction of
display position) on an image signal are illustrated in FIG. 1A,
FIG. 1B, FIG. 1C, and FIG. 1D. In a case where a distortion of an
image is not corrected, the image displayed on the image forming
apparatus (see FIG. 1C) is eventually observed as a state in FIG.
1D by the observer 10. That is a barrel distortion is caused in the
image observed by the observer 10. On the other hand, in case where
a distortion of an image is corrected, an image displayed on the
image forming apparatus (see FIG. 1A) is eventually observed as a
state in FIG. 1B by the observer 10. That is, although a barrel
distortion is caused in the image to be observed by the observer
10, it is possible for the observer 10 to observe the image without
a distortion (see FIG. 1B) eventually since a pincushion distortion
is previously applied to the image displayed on the image forming
apparatus (see FIG. 1A).
[0113] In the display apparatus of the present disclosure, the
image forming apparatus is curved. Thus, for example, it is
possible to reduce a difference between an optical path length of
light emitted from a center part of the image forming apparatus and
an optical path length of light emitted from an edge part of a
display region of the image forming apparatus. As a result, for
example, it is possible to control an increase in a size of a lens
group included in an optical system and to realize a large view
angle with a compact size and light weight. In addition, in the
display apparatus of the first embodiment, a distortion correction
apparatus is included. Thus, a distortion is not caused much in an
image to be observed by an observer.
Second Embodiment
[0114] The second embodiment is a modification of the first
embodiment. A schematic sectional view of a supporting member and
an image forming apparatus included in an image display apparatus
of the second embodiment is illustrated in FIG. 13A. A schematic
sectional view of the supporting member is illustrated in FIG. 13B.
A schematic plane view of the supporting member and the image
forming apparatus is illustrated in FIG. 13C. A schematic sectional
view of the supporting member and the image forming apparatus which
view is along an arrow D-D in FIG. 13A is illustrated in FIG.
13D.
[0115] In the image display apparatus of the second embodiment, an
outer peripheral part of an image forming apparatus 40 which part
is extended in an X-direction is sandwiched by a supporting member
60.sub.2. The supporting member 60.sub.2 includes a lower-side
member 66A and an upper-side member 66B. By a combination of the
lower-side member 66A and the upper-side member 66B, a kind of
frame member is configured. On an inner side surface of the
supporting member 60.sub.2, a groove part 66C is formed. Then, into
the groove part 66C, the outer peripheral part of the image forming
apparatus 40 which part is extended in the X-direction is fit. The
lower-side member 66A and the upper-side member 66B may be fixed to
each other by a screw (not illustrated) or may be fixed to each
other by using an adhesive. The outer peripheral part of the image
forming apparatus 40 which part is extended in the X-direction is
preferably fixed to the groove part 66C by an adhesive. Note that
in the illustrated example, not only the outer peripheral part of
the image forming apparatus 40 which part is extended in the
X-direction but also an outer peripheral part of the image forming
apparatus 40 which part is extended in a Y-direction is sandwiched
by the supporting member 60.sub.2. However, only the outer
peripheral part of the image forming apparatus 40 which part is
extended in the X-direction may be sandwiched by the supporting
member 60.sub.2. In this case, the outer peripheral part of the
image forming apparatus 40 which part is extended in the
Y-direction is preferably fixed to the supporting member 60.sub.2
by using an adhesive.
[0116] Other than the above points, a configuration and structure
of the display apparatus or the image display apparatus of the
second embodiment are similar to the configuration and structure of
the display apparatus or the image display apparatus described in
the first embodiment, and thus, detail description thereof is
omitted.
Third Embodiment
[0117] The third embodiment is a modification of the second
embodiment. An image forming apparatus 40 is curved also in the
third embodiment. However, unlike the second embodiment, a degree
of curvature can be varied. A schematic sectional view of a
supporting member and an image forming apparatus which are included
in an image display apparatus of the third embodiment is
illustrated in FIG. 14A. A schematic plane view of the supporting
member and the image forming apparatus is illustrated in FIG.
14B.
[0118] In the third embodiment, there is a gap between a groove
part 66C and an outer peripheral part of the image forming
apparatus 40 which part is extended in an X-direction. Then, on a
side surface extended in the X-direction of a supporting member
60.sub.3, a projection part 67A and a screw part 67B are provided.
The supporting member 60.sub.3 is stored in a housing (not
illustrated) an upper part of which is open. The housing is
attached to an upper part of each of chassis 53R and 53L. On a side
surface of the housing, a hole part into which the projection part
67A is fit is formed. Also, to a part of the side surface of the
housing which part faces the screw part 67B, a guide groove
substantially extended upward and downward is formed. A screw is
inserted into the guide groove and is screwed into the screw part
67B, whereby, it is possible to fix the supporting member 60.sub.3
on the side surface of the housing. Here, depending on a position
where the screw is fixed in the guide groove, force applied in the
X-direction of the supporting member 60.sub.3 and the image forming
apparatus 40 varies. In FIG. 14A, a center of the projection part
67A is indicated by a cross. Also, a track of a circle of the screw
part 67B with the center of the projection part 67A as a center is
indicated by a dotted line "a" and a track of a center of a through
hole is indicated by a solid line "b". In a case where the screw
part 67B is moved to an upper part in FIG. 14A with the center of
the projection part 67A as the center, a distance between the
center of the projection part 67A and the center of the screw part
67B becomes short. Accordingly, compression force is applied in the
X-direction of the supporting member 60.sub.3 and the image forming
apparatus 40. As a result, a degree of curvature of the image
forming apparatus 40 varies. Since there is a gap between the
groove part 66C and the outer peripheral part of the image forming
apparatus 40 which part is extended in the X-direction, it becomes
possible to permit the variation in the degree of curvature of the
image forming apparatus 40. After the degree of curvature of the
image forming apparatus 40 is determined, the gap is filled by an
adequate material (such as shim). Alternatively, an elastic
material is sandwiched in the gap in advance.
[0119] Note that as illustrated in a schematic sectional view, in
FIG. 14C, of a supporting member and an image forming apparatus
which are included in a modification of the image display apparatus
of the third embodiment, force applied in an X-direction of a
supporting member 60.sub.3 and an image forming apparatus 40 may be
varied by a pushing member 68A and a set-screw 68B to move the
pushing member 68A in the X-direction.
Fourth Embodiment
[0120] The fourth embodiment is a modification of the first to
third embodiments and relates to a display apparatus of a second
configuration of the present disclosure. In a display apparatus of
the fourth embodiment, each image display apparatus 30 further
includes an apparatus of adjusting a distance between an image
forming apparatus and an optical system 90 to adjust a distance
between an image forming apparatus 40 and an optical system 50
(specifically, reflecting mirror 51).
[0121] As described above, to a part, which is extended upward, of
each of chassis 53R and 53L, a supporting member 60.sub.1 or the
like which supports the image forming apparatus 40 is attached. As
illustrated in FIG. 19A, the apparatus of adjusting a distance
between an image forming apparatus and an optical system 90
includes, for example, a base member of an adjustment apparatus 91,
a shaft 92 attached to the supporting member 60.sub.1, a feed screw
mechanism 95 attached to the base member of an adjustment apparatus
91, and a shaft 94 which is extended from the feed screw mechanism
95 and is attached to the supporting member 60.sub.1. The
supporting member 60.sub.1 can freely slide the shaft 92 via a bush
93 and can freely change a distance to the base member of an
adjustment apparatus 91. Then, to the part, which is extended
upward, of each of the chassis 53R and 53L, the base member of an
adjustment apparatus 91 is attached. By rotating the feed screw
mechanism 95, the shaft 94 is moved in an up-down direction in the
drawing. As a result, a distance between the base member of an
adjustment apparatus 91 and the supporting member 60.sub.1 can be
changed. However, movement of the supporting member 60.sub.1 in the
up-down direction in the drawing is regulated by the shaft 92 via
the bush 93.
[0122] Alternatively, as illustrated in FIG. 19B, the apparatus of
adjusting a distance between an image forming apparatus and an
optical system 90 includes, for example, a latch mechanism 96 and a
pin 97 which is fit into the latch mechanism. Then, by moving the
pin 97 in a left direction in the drawing (see arrow in FIG. 19B),
the pin 97 is released from the latch mechanism 96. Then, by moving
the pin 97 in a right direction in the drawing after the supporting
member 60.sub.1 is moved in the up-down direction in the drawing,
the pin 97 is fit into the latch mechanism 96.
[0123] In such a manner, by using the apparatus of adjusting a
distance between an image forming apparatus and an optical system
90 illustrated in FIG. 19A or FIG. 19B, a distance between the
image forming apparatus 40 and the reflecting mirror 51 can be
adjusted and accommodated according to eyesight of an observer.
However, the apparatus of adjusting a distance between an image
forming apparatus and an optical system 90 illustrated in FIG. 19A
or FIG. 19B is an example and any type of apparatus can be used as
long as the apparatus can adjust a distance between the image
forming apparatus and the optical system. For example, instead of
the bush 93, a linear guide rail can be used or a constrained
mechanism between two planes arranged at a right angle can be used.
Also, instead of the feed screw mechanism 95 or the latch mechanism
96, a rack and pinion mechanism may be employed.
[0124] With respect to the distance between the image forming
apparatus 40 and the reflecting mirror 51, a distance detection
apparatus to detect the distance between the image forming
apparatus 40 and the reflecting mirror 51 is arranged in the
apparatus of adjusting a distance between an image forming
apparatus and an optical system 90. The distance detection
apparatus only needs to be an adequate apparatus depending on a
configuration and structure of the apparatus of adjusting a
distance between an image forming apparatus and an optical system
90. More specifically, for example, an apparatus to detect a
position (angle) of the feed screw mechanism 95 or an apparatus to
detect a position of the pin 97 in the latch mechanism 96 may be
used.
[0125] Then, in the display apparatus of the fourth embodiment, a
display control apparatus (not illustrated) to control a size of a
whole image from the image forming apparatus 40 according to a
distance between the image forming apparatus 40 and the reflecting
mirror 51 is further included. That is, as the distance between the
image forming apparatus 40 and the reflecting mirror 51 becomes
shorter, the size of the whole image from the image forming
apparatus 40 is reduced. Note that the control of the size of the
whole image may be a well-known control method such as performing
enlargement/reduction of the size of the whole image by performing
various kinds of signal processing on an image signal used for
forming an image in the image forming apparatus 40. The distance
between the image forming apparatus 40 and the reflecting mirror 51
may be detected by the above-described distance detection
apparatus.
[0126] A relationship between a quantity of movement of the image
forming apparatus 40 with respect to the reflecting mirror 51 and
the size of the whole image, that is, a state in which the distance
between the image forming apparatus and the optical system is
adjusted by the apparatus of adjusting a distance between an image
forming apparatus and an optical system is illustrated conceptually
in FIG. 18. When an observer has a myopic vision compared to a case
where eyesight of an observer is normal (diopter value: 0), a
distance between the image forming apparatus and the optical system
is reduced. Here, as illustrated in FIG. 18, the size of the whole
image from the image forming apparatus 40 is reduced. A
relationship among a diopter value, a quantity of movement of the
image forming apparatus, and a size of the whole image (image
output size) is indicated in the following table 5.
TABLE-US-00005 TABLE 5 Diopter value Quantity of movement Image
output size -3 -9.4 mm 95.5 mm -2 -6.3 mm 97.8 mm -1 -3.1 mm 100.3
mm 0 0 103.4 mm 1 +3.1 mm 106.7 mm 2 +6.3 mm 110.0 mm 3 +9.4 mm
113.8 mm
[0127] When the image forming apparatus 40 (more specifically,
supporting member 60.sub.1) is attached to the part, which is
extended upward, of each of the chassis 53R and 53L, there may be a
case where a fine adjustment in the attachment of the supporting
member 60.sub.1 is necessary. Note that such a fine adjustment is
usually necessary during assembling of the display apparatus. Then,
in such a case, when it is assumed that an axis which passes
through a predetermined point (collision point of an image forming
apparatus and optical axis) of the image forming apparatus 40 and
is parallel in the X-direction is an X-axis and an axis which
passes through the predetermined point (collision point of an image
forming apparatus and optical axis) of the image forming apparatus
40 and is parallel in the Y-direction is a Y-axis (see FIG. 8A),
the image display apparatus 30 includes a rotation apparatus to
rotate the image forming apparatus 40 with at least one of the
X-axis, the Y-axis, and a Z-axis as a center. An example of the
rotation apparatus includes a combination of a set-screw and a
drawing thread which are attached to each of the chassis 53R and
53L. By a fine adjustment of the set-screw and the drawing thread,
it is possible to perform a fine adjustment in the attachment of
the supporting member 60.sub.1 to the part, which is extended
upward, of each of the chassis 53R and 53L. Also, when a guide
groove is provided to the part, which is extended upward, of each
of the chassis 53R and 53L and a feed screw mechanism is provided
to the supporting member 60.sub.1, that is, when a moving apparatus
including a guide groove and a feed screw mechanism is provided, it
is possible to move the image forming apparatus 40 in the
X-direction with respect to the optical system 50 (specifically,
reflecting mirror 51). For example, the image forming apparatus 40
is rotated for 40 mm radians with the X-axis as a center, the image
forming apparatus 40 is rotated for 40 mm radians with the Y-axis
as a center, or the image forming apparatus 40 is rotated for 40 mm
radians with the Z-axis as a center.
[0128] In the display apparatus of the fourth embodiment, since the
apparatus of adjusting a distance between an image forming
apparatus and an optical system is included, a display apparatus
capable of dealing with a difference in eyesight of observers,
which difference is caused depending on the observers, adequately
and easily with a simple configuration and structure can be
provided.
Fifth Embodiment
[0129] The fifth embodiment relates to a display apparatus
according to a second mode of the present disclosure. In a display
apparatus of the fifth embodiment, an optical system 50 is arranged
in such a manner that an image displayed on an image forming
apparatus 40 reaches a pupil 11 of an observer 10 in a defocus
state. Here, the optical system 50 is arranged in such a manner
that an image displayed on the image forming apparatus 40 reaches
the pupil 11 of the observer 10 in a defocus state. Accordingly,
resolution in a horizontal direction of the image is uniformed.
Note that other than the above points, a configuration and
structure of the display apparatus of the fifth embodiment are
similar to the configuration and structure of the display
apparatuses described in the first to the fourth embodiments, and
thus, detail description thereof is omitted. Note that in order to
make the image, which is displayed on the image forming apparatus
40, reach the pupil 11 of the observer 10 in a defocus state, the
image forming apparatus 40 and the optical system 50 (specifically,
distance to lens group 52) are controlled and optimized.
[0130] In FIG. 2B, a result of simulation of resolution in the
horizontal direction of the image to be observed by the observer in
a case where the optical system is arranged in such a manner that
the image displayed on the image forming apparatus reaches the
pupil of the observer in a just-focus state (focused state) is
illustrated. A difference or variation in the resolution in the
horizontal direction of the image with respect to an angle of field
is large. Note that a horizontal axis in each of FIG. 2A and FIG.
2B indicates the angle of field in the horizontal direction and a
horizontal axis indicates resolution. As illustrated in FIG. 2B, in
an angle of field which matches an optical axis (main optical axis)
of the lens group, the resolution in the horizontal direction is
the highest. As an angle of field is deviated from the angle of
field which matches the optical axis (main optical axis) of the
lens group, the resolution in the horizontal direction is decreased
greatly. In addition, for example, in the angle of field which
matches the optical axis (main optical axis) of the lens group,
there is a case where a difference between resolution in the
horizontal direction of an image from the image forming apparatus
for a right eye and resolution in the horizontal direction of an
image from the image forming apparatus for a left eye is large and
a sense of discomfort may be felt. Note that in FIG. 2A and FIG.
2B, an optical axis of a lens group for a right eye is indicated by
"R" and an optical axis of a lens group for a left eye is indicated
by "L", resolution in the horizontal direction of an image acquired
from the image display apparatus for a right eye is indicated by
"a" and resolution in the horizontal direction of an image acquired
from the image display apparatus for a left eye is indicated by
"b".
[0131] On the other hand, in FIG. 2A, a result of simulation of
resolution in the horizontal direction of the image to be observed
by the observer in a case where the optical system is arranged in
such a manner that the image displayed on the image forming
apparatus reaches the pupil of the observer in a defocus state
(underfocus for 0.4 mm) is illustrated. A difference or variation
in the resolution in the horizontal direction of the image with
respect to the angle of field is small. In addition, for example,
in the angle of field which matches the optical axis (main optical
axis) of the lens group, a difference between resolution in the
horizontal direction of an image from the image forming apparatus
for a right eye and resolution in the horizontal direction of an
image from the image forming apparatus for a left eye is small and
a sense of discomfort is not felt much. In such a manner, in the
display apparatus of the fifth embodiment, the optical system is
arranged in such a manner that the image displayed on the image
forming apparatus reaches a pupil of the observer in a defocus
state. Thus, it is possible to control generation of a difference
or variation in the resolution of the image to be observed by the
observer.
[0132] In the above, the present disclosure has been described
based on the preferred embodiments. However, the present disclosure
is not limited to these embodiments. The configuration and
structure of the image display apparatus and the image forming
apparatus which have been described in each of the embodiments are
examples and can be modified arbitrarily. It is also possible to
configure a projector by a combination of the image forming
apparatus and the supporting member to support the image forming
apparatus which have been described in each of the embodiments.
Also, instead of the reflecting mirror, a semi-transmissive mirror
(also referred to as partial-reflecting mirror,
partial-transmissive mirror, semi-transmissive mirror, and half
mirror) can be used.
[0133] Note that, the present disclosure may include the following
configurations.
[0134] [A01]<Display apparatus: first mode>
[0135] A display apparatus including:
[0136] (1) a frame;
[0137] (2) an image display apparatus attached to the frame;
[0138] and
[0139] (3) a distortion correction apparatus, wherein the image
display apparatus includes
[0140] (A) an image forming apparatus and
[0141] (B) an optical system configured to guide an image from the
image forming apparatus to a pupil of an observer,
[0142] when it is assumed that a direction, which corresponds to a
first direction of the image, of the image forming apparatus is an
X-direction and a direction, which corresponds to a second
direction of the image which direction is different from the first
direction, of the image forming apparatus is a Y-direction, the
image forming apparatus is curved in the X-direction or the
Y-direction, or in the X-direction and the Y-direction, and
[0143] the distortion correction apparatus corrects an input image
signal to correct a distortion of the image to be observed.
[0144] [A02] The display apparatus according to [A01], wherein the
distortion correction apparatus corrects the input image signal in
such a manner that a barrel distortion or a pincushion distortion
is applied to an input image signal to be corrected.
[0145] [A03] The display apparatus according to [A01] or [A02],
wherein the distortion correction apparatus corrects, with respect
to the input image signal, at least an image signal corresponding
to both ends of the image forming apparatus and a part nearby to
correct at least a distortion of an image at both of the ends of
the image forming apparatus and the part nearby.
[0146] [A04]<Display apparatus: second mode>
[0147] A display apparatus including:
[0148] (1) a frame; and
[0149] (2) an image display apparatus attached to the frame,
wherein the image display apparatus includes
[0150] (A) an image forming apparatus and
[0151] (B) an optical system configured to guide an image from the
image forming apparatus to a pupil of an observer,
[0152] when it is assumed that a direction, which corresponds to a
first direction of the image, of the image forming apparatus is an
X-direction and a direction, which corresponds to a second
direction of the image which direction is different from the first
direction, of the image forming apparatus is a Y-direction, the
image forming apparatus is curved in the X-direction or the
Y-direction, or in the X-direction and the Y-direction, and
[0153] the optical system is arranged in such a manner that the
image displayed on the image forming apparatus reaches the pupil of
the observer in a defocus state.
[0154] [A05] The display apparatus according to [A04], wherein
resolution in a horizontal direction of the image is uniformed by
the optical system being arranged in such a manner that the image
displayed on the image forming apparatus reaches the pupil of the
observer in the defocus state.
[0155] [B01] The display apparatus according to any one of [A01] to
[A05], wherein
[0156] each image display apparatus further includes a supporting
member configured to support the image forming apparatus, and a
supporting surface of the supporting member configured to support
the image forming apparatus is curved in the X-direction or the
Y-direction, or in the X-direction and the Y-direction, whereby the
image forming apparatus is curved.
[0157] [B02] The display apparatus according to [B01], wherein a
degree of curvature in the X-direction of the supporting surface of
the supporting member is larger than a degree of curvature in the
Y-direction thereof.
[0158] [B03] The display apparatus according to [B01] or [B02],
wherein
[0159] the supporting member includes a pressing member, an outer
shape of the image forming apparatus is a rectangular shape,
and
[0160] an outer peripheral part of the image forming apparatus
which part is extended in the X-direction is fixed to the
supporting member by the pressing member.
[0161] [B04] The display apparatus according to [B01] or [B02],
wherein
[0162] an outer shape of the image forming apparatus is a
rectangular shape, and an outer peripheral part of the image
forming apparatus which part is extended in the X-direction is
sandwiched by the supporting member.
[0163] [C01] The display apparatus according to any one of [A01] to
[B04], wherein the image display apparatus includes an apparatus of
adjusting a distance between an image forming apparatus and an
optical system which apparatus is configured to adjust a distance
between the image forming apparatus and the optical system.
[0164] [C02] The display apparatus according to [C01], further
including a display control apparatus configured to control a size
of a whole image from the image forming apparatus according to the
distance between the image forming apparatus and the optical
system.
[0165] [C03] The display apparatus according to any one of [A01] to
[C02], wherein the image display apparatus includes an apparatus of
adjusting a distance between a pupil and an optical system which
apparatus is configured to adjust a distance between the optical
system and the pupil of the observer.
[0166] [C04] The display apparatus according to any one of [A01] to
[C03], wherein when it is assumed that an axis which passes through
a predetermined point of the image forming apparatus and which is
parallel in the X-direction is an X-axis and an axis which passes
through a predetermined point of the image forming apparatus and
which is parallel in the Y-direction is a Y-axis, the image display
apparatus further includes a rotation apparatus configured to
rotate the image forming apparatus with at least one of the X-axis,
the Y-axis, and a Z-axis as a center.
[0167] [C05] The display apparatus according to any one of [A01] to
[C04], further including a moving apparatus configured to move the
image forming apparatus in the X-direction with respect to the
optical system.
[0168] [D01] The display apparatus according to any one of [A01] to
[C05], wherein an image display apparatus for a left eye and an
image display apparatus for a right eye are attached to the frame,
and each image display apparatus includes
[0169] (A) an image forming apparatus and
[0170] (B) an optical system configured to guide the image from the
image forming apparatus to the pupil of the observer.
[0171] [D02] The display apparatus according to [D01], wherein each
of the optical systems includes a reflecting mirror configured to
reflect the image from the image forming apparatus and a lens group
which is arranged between the pupil of the observer and the
reflecting mirror and into which the image reflected by the
reflecting mirror becomes incident, and
[0172] a normal of the reflecting mirror included in the optical
system of the image display apparatus for a left eye and a normal
of the reflecting mirror included in the optical system of the
image display apparatus for a right eye intersect with each other
in a space on an opposite side of the observer with respect to the
reflecting mirrors.
[0173] [D03] The display apparatus according to [D02], wherein the
normal of the reflecting mirror included in the optical system of
the image display apparatus for a left eye and the normal of the
reflecting mirror included in the optical system of the image
display apparatus for a right eye intersect with each other in a
space lower than a virtual plane including both pupils of the
observer and an infinite distance.
[0174] [D04] The display apparatus according to [D03], wherein when
it is assumed that the virtual plane including both of the pupils
of the observer and the infinite distance is an xy plane, a
straight line which connects both of the pupils of the observer is
an x-axis, an optical axis of a right eye of the observer is an
y-axis, a point on the reflecting mirror at which point an optical
axis of the lens group included in the optical system of the image
display apparatus for a right eye collides with the reflecting
mirror is a collision point of a reflecting mirror for a right eye
and an optical axis, and the reflecting mirror included in the
optical system of the image display apparatus for a right eye is
arranged in parallel with an xz plane, and when it is further
assumed that an axis on the reflecting mirror which axis passes
through the collision point of a reflecting mirror for a right eye
and an optical axis and is in parallel with the xy plane is a
.xi.-axis and an axis on the reflecting mirror which axis passes
through the collision point of a reflecting mirror for a right eye
and an optical axis and is orthogonal to the .xi.-axis is an
.eta.-axis,
[0175] a plane mirror included in the optical system of the image
display apparatus for a right eye is rotated for an angle
.theta..sub.1=45.degree..+-.5.degree. with the .xi.-axis as a
center and with an upper part of the plane mirror being rotated in
a direction away from the observer and is also rotated for an angle
.theta..sub.2=7.degree. to 21.degree. with the .eta.-axis as a
center and with a right end of the plane mirror being rotated in
the direction away from the observer, and the image forming
apparatus and the optical system of the image display apparatus for
a left eye and the image forming apparatus and the optical system
of the image display apparatus for a right eye are arranged in a
mirror-symmetrical manner with respect to a virtual plane which
passes through a midpoint of a line segment to connect both of the
pupils of the observer and is in parallel with a yz plane.
[0176] [D05] The display apparatus according to [D04], wherein the
image forming apparatus is arranged in an upper part of the
reflecting mirror.
[0177] [D06] The display apparatus according to any one of [D01] to
[D05], further including an apparatus of adjusting a distance
between image display apparatuses which apparatus is configured to
adjust a distance between the image display apparatus for a left
eye and the image display apparatus for a right eye.
[0178] [E01] The display apparatus according to any one of [A01] to
[D05], wherein an outer shape of the image forming apparatus is a
rectangular shape, and
[0179] a wiring line is extended to an external part from an outer
peripheral part of the image forming apparatus which part is
extended in the Y-direction.
[0180] [E02] The display apparatus according to any one of [A01] to
[E01], wherein
[0181] one lens group includes three lenses,
[0182] a second lens has negative power, and
[0183] a refractive index of a material included in the second lens
is higher than a refractive index of a material of each of a first
lens and a third lens.
[0184] [E03] The display apparatus according to [E02], wherein the
first lens and the third lens have positive power.
[0185] [E04] The display apparatus according to [E02] or [E03],
wherein a reflecting mirror side of the lens group is a telecentric
optical system.
[0186] [E05] The display apparatus according to any one of [A01] to
[E04], wherein the image forming apparatus includes an organic
electroluminescence display apparatus.
[0187] [E06] The display apparatus according to any one of [A01] to
[E05], wherein a frame is mounted on a head of the observer.
[0188] [F01]<Image display apparatus: first mode>
[0189] An image display apparatus including
[0190] (A) an image forming apparatus and
[0191] (B) an optical system configured to guide an image from the
image forming apparatus to a pupil of an observer, wherein
[0192] when it is assumed that a direction, which corresponds to a
first direction of the image, of the image forming apparatus is an
X-direction and a direction, which corresponds to a second
direction of the image which direction is different from the first
direction, of the image forming apparatus is a Y-direction, the
image forming apparatus is curved in the X-direction or the
Y-direction, or in the X-direction and the Y-direction, and
[0193] an image signal corresponding to both ends of the image
forming apparatus and a part nearby is corrected, with respect to
the input image signal, to correct a distortion of an image at both
of the ends of the image forming apparatus and the part nearby.
[0194] [F02] The image display apparatus according to [F01],
wherein the input image signal is corrected in such a manner that a
pincushion distortion is applied to an input image signal to be
corrected.
[0195] [F03]<Image display apparatus: second mode>
[0196] An image display apparatus including
[0197] (A) an image forming apparatus and
[0198] (B) an optical system configured to guide an image from the
image forming apparatus to a pupil of an observer, wherein
[0199] when it is assumed that a direction, which corresponds to a
first direction of the image, of the image forming apparatus is an
X-direction and a direction, which corresponds to a second
direction of the image which direction is different from the first
direction, of the image forming apparatus is a Y-direction, the
image forming apparatus is curved in the X-direction or the
Y-direction, or in the X-direction and the Y-direction, and
[0200] the optical system is arranged in such a manner that the
image displayed on the image forming apparatus reaches the pupil of
the observer in a defocus state.
[0201] [F04] The image display apparatus according to [F03],
wherein resolution in a horizontal direction of the image is
uniformed by the optical system being arranged in such a manner
that the image displayed on the image forming apparatus reaches the
pupil of the observer in a defocus state.
REFERENCE SIGNS LIST
[0202] 10 Observer [0203] 11, 11L, 11R Pupil of observer [0204] 20
Frame [0205] 21 Front part [0206] 22 Side part [0207] 22A Hole part
[0208] 23A Arm part [0209] 23B Forehead rest [0210] 24 Nose pad
part [0211] 25 Holding member [0212] 26 Base part [0213] 27A Key
[0214] 27B Guide groove [0215] 27C Fastening member [0216] 30, 30R,
30L Image display apparatus [0217] 40 Image forming apparatus
[0218] 41 Wiring line [0219] 50 Optical system [0220] 51, 51R, 51L
Reflecting mirror [0221] 52, 52R, 52L Lens group [0222] 53R, 53L
Chassis [0223] 60.sub.1, 60.sub.2, 60.sub.3 Supporting member
[0224] 61 Supporting surface [0225] 62A, 62B Outer peripheral part
of supporting member [0226] 62C Contact surface of outer peripheral
part [0227] 62D Screw part [0228] 63 Fixing member [0229] 64 Screw
[0230] 65 Pressing member [0231] 65A One end part of pressing
member [0232] 65B Other end part of pressing member [0233] 66A
Lower-side member [0234] 66B Upper-side member [0235] 66C Groove
part [0236] 67A Projection part [0237] 67B Screw part [0238] 68A
Pushing member [0239] 68B Set-screw [0240] 70 Apparatus of
adjusting distance between image display apparatuses [0241] 71
Pedestal [0242] 72 Side surface placed outside of pedestal [0243]
73 Feed screw mechanism [0244] 74A, 76A Pin [0245] 75A Tap hole
[0246] 74B, 75B, 76B Guide groove [0247] 80 Apparatus of adjusting
distance between pupil and optical system [0248] 82 Side wall
[0249] 83 Feed screw mechanism [0250] 90 Apparatus of adjusting
distance between image forming apparatus and optical system [0251]
91 Base member of adjustment apparatus [0252] 92, 94 Shaft [0253]
93 Bush [0254] 95 Feed screw mechanism [0255] 96 Latch mechanism
[0256] 97 Pin fit into latch mechanism
* * * * *