U.S. patent application number 09/801405 was filed with the patent office on 2001-10-25 for information display device.
This patent application is currently assigned to MINOLTA CO., LTD.. Invention is credited to Kasai, Ichiro, Tanijiri, Yasushi, Ueda, Hiroaki.
Application Number | 20010033401 09/801405 |
Document ID | / |
Family ID | 26588146 |
Filed Date | 2001-10-25 |
United States Patent
Application |
20010033401 |
Kind Code |
A1 |
Kasai, Ichiro ; et
al. |
October 25, 2001 |
Information display device
Abstract
An information display device provided with a prism having at
least two reflecting surfaces arranged in facing each other and a
hologram surface formed of a reflection-type hologram. And at least
one of the two reflecting surfaces is a light-beam-selective
surface that selectively transmits or reflects light in accordance
with its incident angle. An image light emitted from an image
display means enters the prism, and is reflected between the
reflecting surfaces, and then is diffractively reflected on the
hologram surface, and, after being transmitted through the
light-beam-selective surface, is directed to an observer's
pupil.
Inventors: |
Kasai, Ichiro;
(Kawachinagano-shi, JP) ; Ueda, Hiroaki;
(Suita-shi, JP) ; Tanijiri, Yasushi;
(Osakasayama-shi, JP) |
Correspondence
Address: |
SIDLEY AUSTIN BROWN & WOOD
717 NORTH HARWOOD
SUITE 3400
DALLAS
TX
75201
US
|
Assignee: |
MINOLTA CO., LTD.
|
Family ID: |
26588146 |
Appl. No.: |
09/801405 |
Filed: |
March 8, 2001 |
Current U.S.
Class: |
359/15 ; 359/16;
359/34 |
Current CPC
Class: |
G02B 27/0172 20130101;
G02B 27/0081 20130101; G02B 2027/0178 20130101 |
Class at
Publication: |
359/15 ; 359/16;
359/34 |
International
Class: |
G02B 005/32; G03H
001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 17, 2000 |
JP |
2000-81681 |
Mar 17, 2000 |
JP |
2000-81682 |
Claims
What is claimed is:
1. An information display device comprising: an image display
member which displays images; and a prism having at least two
reflecting surfaces arranged in facing each other, and a hologram
surface formed of a reflection-type hologram, and at least one of
the two reflecting surfaces arranged in facing each other is a
light-beam-selective surface which selectively transmits or
reflects light, wherein an image light beam that corresponds to
image information and that exits from the image display member is
reflected between the two reflecting surfaces arranged in facing
each other, and is diffractively reflected on the hologram surface,
and then, after being transmitted through the light-beam-selective
surface, is directed to an observer's pupil.
2. An information display device as claimed in claim 1, wherein the
hologram is a volume hologram.
3. An information display device as claimed in claim 1, wherein the
hologram is a phase hologram.
4. An information display device as claimed in claim 1, wherein the
hologram has optical power for projecting an image on an observer's
pupil, while enlarging it.
5. An information display device as claimed in claim 1, wherein the
hologram has a diffractive reflection angle wider than a regular
reflection angle observed on the hologram surface.
6. An information display device as claimed in claim 1, wherein the
reflecting surfaces arranged in facing each other have an
inclination opening toward the incident side of a prism of the
image light beam.
7. An information display device as claimed in claim 1, further
comprising a deflection correction member for correcting deflection
of external light that is transmitted through a prism.
8. An information display device as claimed in claim 7, wherein the
deflection correction member is attached to the prism and has
surfaces on the same surfaces of the reflecting surfaces arranged
in facing each other.
9. An information display device as claimed in claim 1, wherein the
reflecting surfaces arranged in facing each other are substantially
parallel to each other.
10. An information display device as claimed in claim 1, wherein
reflection occurring between the reflecting surfaces arranged in
facing each other is total reflection.
11. An information display device as claimed in claim 1, wherein
the hologram surface is plane.
12. An information display device as claimed in claim 1, wherein at
least one of the two reflecting surfaces arranged in facing each
other is a curved surface.
13. An information display device comprising: a first image display
member for displaying a first image; a first prism having at least
two reflecting surfaces arranged in facing each other and another
reflecting surface, and at least one of the two reflecting surfaces
arranged in facing each other is a light-beam-selective surface
which selectively transmits or reflects light; a second image
display member for displaying a second image; and a second prism
having the same construction as the first prism, wherein an image
light beam corresponding to the information of the first image
exiting from the first image display member is reflected between
the two reflecting surfaces of the first prism arranged in facing
each other, and is reflected on another reflecting surface of the
first prism, and then, after being transmitted through the
light-beam-selective surface, is directed to an observer's pupil,
on the other hand, an image light beam corresponding to the
information of the second image exiting from the second image
display member is reflected between the two reflecting surfaces of
the second prism arranged in facing each other, and is reflected on
another reflecting surface, and then is, after being transmitted
through the light-beam-selective surface, directed to the same
observer's pupil as the light beam of the first image.
14. An information display device as claimed in claim 13, wherein
the another reflecting surface has optical power for projecting an
image on an observer's pupil, while enlarging it.
15. An information display device as claimed in claim 13, wherein
the another reflecting surface has an angle inclined to the
incidental side of the prism of the image light beam.
16. An information display device as claimed in claim 13, wherein
the first image display member and the second image display member
are connected to each other
17. An information display device as claimed in claim 13, further
comprising: a deflection correction member for correcting
deflection of external light that is transmitted through the
prism.
18. An information display device as claimed in claim 13, wherein
the another reflecting surface is a hologram surface formed of a
reflection-type hologram.
19. An information display device as claimed in claim 18, wherein
the hologram is a volume hologram.
20. An information display device as claimed in claim 18, wherein
the hologram is a phase hologram.
21. An information display device as claimed in claim 18, wherein
the hologram has optical power for projecting an image on an
observer's pupil, while enlarging it.
22. An information display device as claimed in claim 18, wherein
the hologram has a diffractive reflection angle wider than a
regular reflection angle observed on the hologram surface.
23. An information display device as claimed in claim 13, wherein
the reflecting surfaces arranged in facing each other has an
inclination opening toward the incident side of the prism of the
image light beam.
24. An information display device as claimed in claim 13, further
comprising a deflection correction member for correcting deflection
of external light that is transmitted through the prism.
25. An information display device as claimed in claim 13, wherein
the reflecting surfaces arranged in facing each other are
substantially parallel to each other.
26. An information display device as claimed in claim 13, wherein
reflection occurring between the reflecting surfaces arranged in
facing each other is total reflection.
27. An information display device as claimed in claim 13, wherein
at least one of the two reflecting surfaces arranged in facing each
other is a curved surface.
28. An optical element comprising: two reflecting surfaces arranged
in facing each other, and at least one of the two reflecting
surfaces is a light-beam-selective surface that selectively
transmits or reflects light; and a hologram surface formed of a
reflection-type hologram, wherein light entering the optical
element is reflected on the two reflecting surfaces, and after
being reflected on the hologram surface is transmitted through the
light-beam-selective surface and then exits therefrom.
29. An optical element as claimed in claim 28, wherein the third
reflecting surface has positive optical power.
30. An optical element as claimed in claim 28, wherein the optical
element is a prism.
31. An optical element comprising: two reflecting surfaces arranged
in facing each other, and at least one of the two reflecting
surfaces is a light-beam-selective surface that selectively
transmits or reflects light; and two hologram surface formed of a
reflection-type holograms, wherein light entering the optical
element is reflected between the two reflecting surfaces, and is
reflected on the one of two hologram surfaces, and then is
transmitted through the light-beam-selective surface, on the other
hand, light which is different from the light to be reflected on
the one of two hologram surfaces entering the optical element is
reflected between the two reflecting surfaces, and is reflected on
the other two hologram surfaces, after then, is transmitted through
the light beam-selective surface.
Description
[0001] This application is based on application Nos. 2000-81681 and
2000-81682 filed in Japan on Mar. 17, 2000, the entire contents of
which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an information display
device, and particularly to an information display device for use
in an image display apparatus that is used with being placed in
front of an observer's eyes.
[0004] 2. Description of the Prior Art
[0005] Conventionally, several image display apparatuses that are
used in front of an observer's eyes with being mounted on an
observer's head or face, or being held with hands are known, and
they are manufactured for use in the field of virtual reality and
in the so-called personal theaters. In recent years, an image
display apparatus serving as a display for a wearable computer has
been studied.
[0006] As a detailed construction, for example, Japanese Laid-Open
Patent Application No. H7-333551 discloses a construction, that is,
in an observation optical system that directs light emitted from an
original image to an observer's eyeballs, the light is totally
reflected from a curved surface in the direction away from the
eyeballs, and the totally reflected light is reflected on
reflecting surfaces, preferably, on the reflecting surfaces having
different optical powers resulting from the difference in their
azimuth angles, and then the light is transmitted through the
curved surface and directed to the eyeballs.
[0007] Japanese Laid-Open Patent Application No. H9-197336
discloses another construction, that is, in an image display
apparatus composed of an image display element for displaying
images and an eyepiece optical system (ocular optical system) for
directing the image formed on the image display element to an
observer's eyeballs without achieving image formation in an optical
path, the eyepiece optical system has at least three surfaces, and
the light exiting from the image display element is reflected at
least three times on the at least three surfaces and reaches the
observer's eyeballs, and at least one of the three reflecting
surfaces is a concave mirror concave to the observer's eyeballs
side.
[0008] U.S. Pat. No. 5,790,311 discloses another construction
comprising at least three juxtaposed optical surfaces,
characterized in that at least two optical surfaces of these three
optical surfaces are defined by curved surfaces concave to a pupil
position side of the optics system and at least four reflections
occur between the curved surfaces.
[0009] U.S. Pat. No. 5,699,194 discloses another construction that
includes an image display device for displaying an image, and an
ocular optical system for projecting the image formed by the image
display device and for leading the projected image to an observer's
eyeballs. In this image display apparatus, the ocular optical
system is arranged such that light rays emitted from the image
display device are reflected three or higher odd-numbered times
before reaching the observer's eyeball, and that a surface of the
ocular optical system that is disposed immediately in front of the
observer's eyeball is a reflecting surface which internally
reflects the light rays, and through which the light rays exit from
the ocular optical system.
[0010] Japanese Laid-Open Patent Application No. H10-307263
discloses another construction in which a prism optical element
formed of a plurality of surfaces with a medium having a refractive
index larger than 1 in between includes a first to a fourth
surface. The first surface has both a transmitting action that
permits light to enter the inside of the prism optical element or
to exit from the inside of the prism optical element, and an
internally reflecting action in the prism optical element. The
second surface is so arranged as to face the first surface with the
medium in between, and has an internally reflecting action in the
prism optical element. The third surface is so arranged as to be
substantially adjacent to the second surface and as to face the
first surface with the medium in between, and has an internally
reflecting action in the prism optical element. And the fourth
surface has a transmitting action that, when the first surface has
an action of permitting light to enter the inside of the prism
optical element, permits light to exit from the inside of the prism
optical element, and that, when the first surface has an action of
permitting light to exit from the inside of the prism optical
element, permits light to enter the inside of the prism optical
element. And this construction fulfills a range defined by a
predetermined condition.
[0011] U.S. Pat. No. 6,094,241 discloses another construction that
has a display optical system for guiding a light beam from a
display means displaying image information to an eyeball of an
observer, and an image-pickup optical system for focusing a light
beam from the outside on an image-pickup device. This construction
includes an optical path separating means provided in an optical
path that is arranged to substantially align an eyeball optical
axis of a light beam incident from the display optical system to
the eyeball of the observer or a virtual eyeball optical axis as an
extension of the eyeball optical axis with an outside optical axis
of a light beam incident from the outside of the image-pickup
optical system, and a shield means for preventing the light beam
from the display means from entering the image pickup device of the
image-pickup optical system.
[0012] Japanese Laid-Open Patent Application No. H5-346508
discloses another construction including a hologram lens by which a
light beam corresponding to image information transmitted from an
image display device is diffracted in a predetermined direction,
and the image information and other image information are spatially
superimposed for being observed in an identical field of view.
Here, the hologram lens is of an off-axial type composed of a
plurality of elemental holograms having the same numerical
aperture.
[0013] Japanese Laid-Open Patent Application No. H9-185009
discloses another construction that includes an image display means
arranged on a predetermined part of spectacles such as spectacle
lenses or spectacle frames for outputting a displayed image toward
the spectacle lenses, and a see-through means that enables an
observer to observe, through the spectacle lenses, the displayed
image and the outside at the same time.
[0014] Japanese Laid-Open Patent Application No. H10-319343
discloses another construction including an image display means for
emitting image display light, a bundle of optical fibers that
reduces the image display light transmitted from the image display
means and emits it via the end of an exiting surface, and an
in-front-of-eyes optical means that directs the image display light
exiting from the end of the exiting surface of the bundle of
optical fibers to an observer's eyes by diffracting or reflecting
it in order to make the observer observe a virtual image formed in
accordance with the image display light.
[0015] U.S. Pat. No. 5,453,877 discloses another construction
including, in series: a generator or source of light images to
provide a light radiation, a collimation objective or collimator to
collimate the radiation, a combiner comprising a confocal assembly
with a first parabolic mirror, a second parabolic mirror, and a
transparent plate. The first mirror is reflective to reflect the
collimated radiation towards the second mirror, and the second
mirror is partially transparent to enable, simultaneously, the
transmission by reflection, towards an observer, of the radiation
received from the first mirror, and the transmission by
transparency, towards the observer, of an external radiation. The
transparent plate have two ends being formed, respectively, by the
two parabolic mirrors, and a first and a second surface thereof are
parallel. And an optical path of the collimated radiation between
the objective and the observer includes, substantially, a first
crossing of one of the two parallel faces, a reflection on the
first mirror, several total reflection on the parallel faces, a
reflection on the second mirror and a second crossing of one of the
two parallel faces, wherein the plate is formed by several
elements, each of the two parallel faces being formed by a surface
for each element, and the surfaces being arranged so as to
constitute a folded version of the system.
[0016] U.S. Pat. No. 6,008,778 discloses another construction
including an ocular optical system that leads an image formed by
two-dimensional display means to an eyeball of an observer to
thereby project the image as an enlarged virtual image. The
two-dimensional display means has a first two-dimensional display
device and a second two-dimensional display device. An ocular
optical system includes a first surface having both reflecting and
transmitting actions, a second surface having at least reflecting
action, and a third surface having at least reflecting action. The
first surface is disposed to face an observer's eyeball. The second
surface is disposed to face the first surface. The third surface is
disposed to face the first surface in a side-by-side relation to
the second surface. Thus, images displayed by the first and second
two-dimensional display devices are led to the observer's
eyeball.
[0017] In the construction disclosed in Japanese Laid-Open Patent
Application No. H7-333551 previously described, an observation
optical system is composed of a prism using concave reflecting
surfaces including a light-beam-selective surface for selectively
performing total reflection or transmission in accordance with the
incident angle of a light beam; however, it is so designed that, in
the prism, reflection occurs with geometrical
regular-reflection-angles, and this is disadvantageous in making
the optical system thinner. In addition, in the prism, there is no
portion where reflection occurs between the surfaces facing each
other, in other words, the prism does not have a light-beam-guide
portion, and this makes the prism thicker. Furthermore, this
apparatus is provided with a so-called see-through function for
simultaneously observing a displayed image and an external image;
however, a combiner thereof has a semi-transmissive surface, and
therefore the light amount of the external image and the displayed
image is reduced to as a low level of half of the original amounts.
In this construction, prisms for correcting the distortion of a
transmitted image delivered from the outside are connected on a
curved surface, and this makes it difficult to manufacture this
apparatus.
[0018] In the constructions disclosed in Japanese Laid-Open Patent
Application No. H9-197336, U.S. Pat. No. 5,790,311, and U.S. Pat.
No. 5,699,194 previously described, a prism has surfaces facing
each other and free-form surfaces partly including a
light-beam-selective surface that selectively performs total
reflection or transmission in accordance with the incident angle of
a light beam. Here, a light beam is directed to a concave
reflecting surface through reflection occurring between the
surfaces facing each other. However, the same as the construction
mentioned above, they are so designed that reflection occurs in the
prisms with geometrical regular-reflection-angles, and this is
disadvantageous in making the optical system thinner.
[0019] In the constructions disclosed in Japanese Laid-Open Patent
Application No. H10-307263, and U.S. Pat. No. 6,094,241 described
previously, the same as the construction mentioned above, a prism
has surfaces facing each other and free-form surfaces partly
including a light-beam-selective surface that selectively performs
total reflection or transmission in accordance with the incident
angle of a light beam. It is so designed that a light beam is
directed to a concave reflecting surface through reflection
occurring between the surfaces facing each other. And these
constructions makes it possible to achieve see-through observation
of a transmitted image delivered from the outside. However, the
same as the construction previously described, it is so designed
that, in the prism, reflection occurs with geometrical
regular-reflection-angles, and this is disadvantageous in making
the optical system thinner.
[0020] Especially, in the construction disclosed in Japanese
Laid-Open Patent Application No. H10-307263, see-through
observation of a transmitted image delivered from the outside is
achieved out of an image display area, and therefore it is
impossible to secure a wide external observed area. This
application includes a practical example in which the outside is
observed while withdrawing a prism; however, this requires a
movable portion, and therefore it makes the construction
complicated. In the construction disclosed in U.S. Pat. No.
6,094,241, a half mirror is used as a combiner, and therefore the
transmitted image delivered from the outside becomes dark.
[0021] Japanese Laid-Open Patent Application Nos. H5-346508,
H9-185009, and H10-319343 disclose constructions in which, as a
combiner, a reflection-type hologram lens is used; however, their
optical systems are not so deigned as to fold light beams from the
displayed image and are thus less compact. In addition, in order to
separate the displaying light beams from the observing light beams,
a decentering amount of the hologram combiner is increased and
aberrations caused by decentering occur (hereinafter, aberrations
caused by decentering will be referred to as "decentering
aberrations"), and therefore it is impossible to obtain a favorable
displayed image. Especially, the construction disclosed in Japanese
Laid-Open Patent Application No. H9-185009 has a large decentering
amount, and therefore it is substantially impossible to obtain a
wide angle of view.
[0022] In the construction disclosed in U.S. Pat. No. 5,453,877, to
a prism using concave reflecting surfaces including a
light-beam-selective surface that selectively performs total
reflection or transmission in accordance with the incidental angle
of a light beam, a prism for correcting distortion of a transmitted
image delivered from the outside is attached. Here, as a display
optical system, an image-reformation optical system is used, and
therefore this is less compact. In addition, an eyepiece function
of the display optical system is achieved by reflection on the
concave reflecting surface, and a hologram functions only as a
combiner and does not have any optical power for such as condensing
light. Therefore, reflection occurring in the prism (or a plate in
a practical example) has geometrical regular-reflection-angles, and
this is disadvantageous in making the optical system thinner.
Furthermore, it is difficult to form a hologram on a concave
reflecting surface.
[0023] In the construction disclosed in U.S. Pat. No. 6,008,778
previously described, because of its optical construction, an image
light beam passes a half-mirror twice, and therefore its light
amount is reduced to less than one fourth of the original amount,
and this makes the obtained image dark. In addition, in a prism,
there is no portion where reflection occurs between the surfaces
facing each other, in other words, there is no light-beam-guide
portion, and this makes the prism thicker. Furthermore, it is so
designed that a display element is arranged in front of an
observer, and therefore it is impossible to provide this apparatus
with a see-through function which enables the observer observe a
displayed image and an external image at the same time.
SUMMARY OF THE INVENTION
[0024] An object of the present invention is to provide an
information display device that can realize a thin and compact
construction, obtain a fine image even while securing a wide angle
of view, and achieve see-through observation of the outside in a
natural manner.
[0025] To achieve the above object, according to one aspect of the
present invention, an information display apparatus is provided
with: an image display member which displays images; and a prism
having at least two reflecting surfaces arranged in facing each
other and another hologram surface formed of a reflection-type
hologram, and at least one of the two reflecting surfaces arranged
in facing each other is a light-beam-selective surface which
selectively transmits or reflects light, wherein an image light
beam corresponding to image information exiting from the image
display member is reflected between the two reflecting surfaces
arranged in facing each other, and is diffractively reflected on
the hologram surface, and then, after being transmitted through the
light-beam-selective surface, is directed to an observer's
pupil.
[0026] According to another aspect of the present invention, an
information display apparatus is provided with: a first image
display member for displaying a first image; a first prism having
at least two reflecting surfaces arranged in facing each other and
another reflecting surface, and at least one of the two reflecting
surfaces arranged in facing each other is a light-beam-selective
surface which selectively transmits or reflects light; a second
image display member for displaying a second image; and a second
prism having the same construction as the first prism, wherein an
image light beam corresponding to the information of the first
image exiting from the first image display member is reflected
between the two reflecting surfaces of the first prism arranged in
facing each other, and is reflected on another reflecting surface
of the first prism, and then, after being transmitted through the
light-beam-selective surface, is directed to an observer's pupil,
on the other hand, an image light beam corresponding to the
information of the second image exiting from the second image
display member is reflected between the two reflecting surfaces of
the second prism arranged in facing each other, and is reflected on
another reflecting surface, and then is, after being transmitted
through the light-beam-selective surface, directed to the same
observer's pupil as the light beam of the first image.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] This and other objects and features of this invention will
become clear from the following description, taken in conjunction
with the preferred embodiments with reference to the accompanied
drawings in which:
[0028] FIGS. 1A and 1B are diagrams comparatively explaining
geometrical regular reflection and diffractive reflection on a
hologram;
[0029] FIG. 2 is a diagram comparatively explaining geometrical
regular reflection and diffractive reflection on a hologram;
[0030] FIG. 3 is a graph explaining the range of a diffractive
wavelength of a transmission-type and a reflection-type
hologram;
[0031] FIG. 4 is a graph showing the relationship between the
intensities of reflected light and transmitted light relative to
the wavelength of an incident light (monochrome);
[0032] FIG. 5 is a graph showing the relationship between the
intensities of reflected light and transmitted light relative to
the wavelength of an incident light (color);
[0033] FIG. 6 is a diagram schematically illustrating the outline
of the construction of an optical system forming a hologram;
[0034] FIG. 7 is a vertical sectional view schematically
illustrating the construction of an information display device of a
first embodiment of the present invention;
[0035] FIG. 8 is a vertical sectional view schematically
illustrating the construction of an information display device of a
second embodiment of the present invention;
[0036] FIG. 9 is a vertical sectional view schematically
illustrating the construction of an information display device of a
third embodiment of the present invention;
[0037] FIG. 10 is a vertical sectional view schematically
illustrating the construction of an information display device of a
fourth embodiment of the present invention;
[0038] FIG. 11 is a vertical sectional view schematically
illustrating the construction of an information display device of a
fifth embodiment of the present invention;
[0039] FIG. 12 is a vertical sectional view schematically
illustrating the construction of an information display device of a
sixth embodiment of the present invention;
[0040] FIG. 13 is a vertical sectional view schematically
illustrating the construction of an information display device of a
seventh embodiment of the present invention;
[0041] FIG. 14 is a vertical sectional view schematically
illustrating the construction of an information display device of
an eighth embodiment of the present invention;
[0042] FIG. 15 is a vertical sectional view schematically
illustrating the construction of an information display device of a
ninth embodiment of the present invention;
[0043] FIG. 16 is a vertical sectional view schematically
illustrating the construction of an information display device of a
tenth embodiment of the present invention;
[0044] FIG. 17 is a vertical sectional view schematically
illustrating the construction of an information display device of
an eleventh embodiment of the present invention;
[0045] FIG. 18 is a vertical sectional view schematically
illustrating the construction of an information display device of a
twelfth embodiment of the present invention;
[0046] FIG. 19 is a vertical sectional view schematically
illustrating the construction of an information display device of a
thirteenth embodiment of the present invention;
[0047] FIG. 20 is a vertical sectional view schematically
illustrating the construction of an information display device of a
fourteenth embodiment of the present invention;
[0048] FIG. 21 is a diagram showing an outlook of an example of a
head-mounted image display apparatus employing the present
invention;
[0049] FIG. 22 is a vertical sectional view illustrating an
information display device employed in a head-mounted image display
apparatus;
[0050] FIG. 23 is a diagram illustrating an outlook of another
example of a head-mounted image display apparatus employing the
present invention;
[0051] FIG. 24 is a vertical sectional view illustrating an
information display device employed in a head-mounted image display
apparatus;
[0052] FIG. 25 is a diagram illustrating an outlook of an example
applying the present invention to a portable telephone; and
[0053] FIG. 26 is a vertical sectional view illustrating an
information display device of an image display apparatus integrated
in a flipper of a portable telephone.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0054] Hereinafter, embodiments of the present invention will be
described with reference to drawings. In an information display
device employed in the present invention, a hologram lens is used,
and an arbitrary displayed image formed on an image display element
such as a liquid crystal display is directed to a pupil to be
observed. FIGS. 1A and 1B are diagrams schematically explaining,
regarding a construction in which a displayed image is directed to
a pupil for being observed, the comparison between a case using
geometrical regular reflection and another case using diffractive
reflection on a hologram. FIG. 1A shows a case using geometrical
regular reflection, and FIG. 1B shows another case using
diffractive reflection on a hologram, respectively.
[0055] In FIG. 1A, reference numeral 101 represents a prism serving
as a light-guide portion, reference numeral 101a represents a
concave reflecting surface that is obliquely arranged on the lower
end of the prism 101, and reference numeral 103 represents a pupil.
In FIG. 1B, reference numeral 102 represents a prism serving as a
light-guide portion, reference numeral 102a represents a hologram
surface that is obliquely arranged on the lower end of the prism
102, and reference numeral 103 represents a pupil. As shown in FIG.
1A, a light beam L emitted from a displayed image is transmitted
downward in the prism 101, and is regularly reflected on the
concave reflecting surface 101a, and then is directed to the pupil
103 while being condensed. On the other hand, as shown in FIG. 1B,
a light beam La emitted from a displayed image is transmitted
downward in the prism 102, and is diffractively reflected on the
hologram surface 102a, and then is directed to the pupil 103 while
being condensed.
[0056] Here, as described earlier, a hologram functions as a
diffractive element and can achieve diffractive reflection which is
different from geometrical regular reflection achieved by a mirror
or the like. In other words, regardless of the inclination of a
hologram substrate, it is possible to diffractively reflect light
in an arbitrary direction, and therefore the size of an optical
system is not defined by the geometric conditions.
[0057] Specifically, for example, as schematically shown in FIG. 2,
when incident light 1s having entered a reflecting surface 104 is
regularly reflected and the thus obtained reflected light is drawn
with a broken line and expressed as 1a, both the incident angle and
the reflection angle become .alpha., the same angle. However, when
a diffractive reflecting surface is used as the reflecting surface
104, it is possible to make a reflection angle .beta. of a
diffractively reflected light 1b that is drawn with a solid line
wider than .alpha.. Because of this property, if the direction of
the reflected light is the same, compare to the case that the
reflecting surface achieves regular reflection, it is possible to
make the inclination of the reflecting surface smaller.
[0058] Therefore, as shown in FIGS. 1A and 1B, respectively, if the
position of the pupil 103 is the same, the hologram surface 102a
can be arranged in a less inclined status compare to the concave
reflecting surface 101a, and this helps make the thickness ta of
the prism 102 thinner than the thickness t of the prism 101a. In
addition, although a hologram is formed as a flat surface, it can
have optical power, and therefore when the hologram is made to have
a see-through function described later, through its diffractive
reflection, it functions as a lens element and affects the light
beam traveled from the displayed image, on the other hand, it does
not affect external light, and this property makes it possible to
observe an external image in a natural manner.
[0059] Another construction of the information display device
employed in the present invention includes two image display
elements, and, by using the eyepiece optical systems corresponding
to the individual image display elements, it makes a light beam
emitted from the each image display element enter one pupil. The
individual image display elemetns and eyepiece optical systems
correspond to the different display areas, respectively, and by
observing with putting these display areas together, it designs to
widen the angle of view (angle of visibility of displayed image),
while realizing a thin and compact structure.
[0060] In addition, in the eyepiece optical systems, reflection
occurring between the reflecting surfaces facing each other shall
be total-reflection, and by that reflection, a light beam from the
displayed image is guided, and therefore it is possible to realize
a construction in which the image display elements do not intercept
an ordinary viewing zone. In this construction, external light is
not intercepted, and therefore it is possible to have the
see-through function which enables an observer to observe the
displayed image and the external image simultaneously, and, at the
same time, it can obtain a wide external observed area.
[0061] When a hologram is used for achieving an eyepiece optical
function, it is possible to perform see-through observation in a
better and more natural manner. As mentioned above, although a
hologram is formed as a flat surface, it can have optical power,
and therefore when it is made to have the see-through function,
through its diffractive reflection, it functions as a lens element
and affects the light beam traveled from the displayed image, on
the other hand, it does not affect external light, and thereby it
is possible to observe an external image in a natural manner.
[0062] FIG. 3 is a graph explaining the range of a diffractive
wavelength of a transmission-type and a reflection-type hologram.
This graph indicates the wavelength selectivity of a
transmission-type and a reflection-type hologram relative to the
difference in angles between an incident light and an exiting
light, on condition that the refractive index of a holographic
photosensitive material is 1.5, its recording wavelength is 530 nm,
and the thickness of the holographic photosensitive material is 5
.mu.m. In this graph, the axis of abscissa represents the
difference in angles, and the axis of ordinate represents the range
of a diffractive wavelength. As shown in the graph, when the
difference in angles is equal or smaller than 90.degree., in other
words, in a case of a transmission-type hologram, it is found that
the range of a diffractive wavelength becomes very wide, namely
longer than one hundred and several dozens nm. The wavelength of a
visible light falls between around 400 nm to 700 nm with having the
range of wavelength around 300 nm, and therefore there may be a
case that a transmission-type hologram affects almost all sorts of
visible light.
[0063] On the other hand, when the difference in angles is greater
than 90.degree., in other words, in a case of a reflection-type
hologram, the range of a diffractive wavelength becomes remarkably
narrow compare to a transmission-type hologram, and therefore its
wavelength selectivity becomes very high. In other words, a
reflection-type hologram has a property that affects a certain
wavelength, but does not affect other wavelengths than that. When a
reflection-type hologram is used as a combiner for achieving the
see-through function which enables an observer to observe a
displayed image and an external image simultaneously, because it
affects only a certain wavelength, the external light receives
little influence from the combiner and this makes it possible to
perform see-through observation in a bright and good condition.
[0064] FIG. 4 is a graph showing, in a monochrome reflection-type
hologram, one example of the relationship between the luminous
intensities of reflected and transmitted light relative to the
incident light having a wavelength that falls in the range of
visible light. In this graph, the axis of abscissa represents the
wavelength (nm), and the axis of ordinate represents the
reflectance or transmittance (%). A curve a drawn with a solid line
indicates the reflectance, and a curve b drawn with a broken line
indicates the transmittance, respectively. A reflection-type
hologram affects only light having a specific wavelength
(diffractive wavelength), and therefore, as shown in the graph,
here, it reflects the light having a wavelength around 530 nm and
transmits the light having wavelengths other than that. This makes
it possible to perform see-through type information display in
which an observer observes external light and image light while
superimposing them.
[0065] FIG. 5 is a graph showing, in a color reflection-type
hologram, one example of the relationship between the luminous
intensities of reflected and transmitted light relative to the
incident light having a wavelength that falls in the range of
visible light. In this graph, the axis of abscissa represents the
wavelength (nm), and the axis of ordinate represents the
reflectance or transmittance (%). A curve a drawn with a solid line
indicates the reflectance, and a curve b drawn with a broken line
indicates the transmittance, respectively. A reflection-type
hologram affects only light having a specific wavelength
(diffractive wavelength), and therefore, as shown in the graph,
here, it reflects the light having the wavelengths of R, G, and B,
and transmits light having other wavelengths.
[0066] Because of this property, even when color image light is
displayed, it is possible to achieve see-through type information
display in which an observer observes external light and image
light while superimposing them. A hologram has a diffractive
wavelength corresponding to its recording wavelength, and therefore
the above mentioned hologram can be obtained by providing
multiple-exposure with different wavelengths on a single
holographic photosensitive material, or by putting holograms made
by different recording wavelengths in layers.
[0067] FIG. 6 is a diagram schematically illustrating the outline
of the construction of an optical system forming a hologram
(hereinafter, such an optical system is referred to as a
"manufacturing optical system"). In the information display device
of the present invention, a hologram lens is obliquely arranged
relative to a light beam of the displayed image and has optical
power as an eyepiece optical system, and therefore it forms a
nonaxismmetric optical system. When this nonaxismmetric optical
system performs only the same function as that of a centered lens,
asymmetrical distortion (trapezoid distortion) caused by
decentering or curvature of image surface occurs. In order to
prevent this, it is preferable that a hologram be provided with not
only rotationally symmetrical wavefront reproducibility but also
free-form surface wavefront reproducibility.
[0068] As shown in this figure, this kind of hologram is formed by
using a manufacturing optical system Gr in which a plurality of
lenses are decentered and combined together. Here, a construction
for manufacturing a hologram lens employed in an information
display device in a first embodiment described latter is cited as
an example. For manufacturing a hologram lens, a laser beam is
split into two beams of light by a beam splitter, and two point
light sources A, B, namely a first and a second point light source,
are arranged in the individual beams of light, and make the light
emitted from the two point light sources enter a holographic
photosensitive material H that is obliquely arranged on the lower
end of a prism 1.
[0069] Here, the second point light source B is so arranged as to
substantially correspond to the position of an observer's pupil in
the displayed image of the information display device. By arranging
the second point light source B in this way, the optical path of
light emitted from the second point light source B and that of
light from the displayed image become substantially identical, and
this makes it possible to make the diffraction efficiency utmost
while the hologram lens is in a use. In addition, between the first
point light source A and the holographic photosensitive material H,
the manufacturing optical system Gr mentioned above is arranged
which is composed of five lenses G1 to G5 that are decentered and
combined together. This manufacturing optical system Gr is so
deigned that the wavefront of the light emitted from the first
point light source A is so controlled that the displayed image is
observed in a good condition.
[0070] Note that, as a hologram used in the embodiments described
latter, for obtaining high diffraction efficiency and a bright
displayed image and external image, it is preferable that the
hologram be reflection type and among which a so-called volume
hologram having a certain thickness, at the same time, a phase
hologram exhibiting low absorbency of light is best suited.
[0071] FIG. 7 is a vertical sectional view schematically
illustrating the construction of an information display device of a
first embodiment of the present invention. In this figure, a prism
1 has a plate-like form with obliquely spreading in the upper right
direction, and its upper end surface is an incident surface r7.
And, on the left and right of the figure, it has a first reflecting
surface r6 and a second reflecting surface r5 that face each other
with being arranged substantially parallel to each other.
Furthermore, on a lower end surface, a hologram surface r3 is
obliquely arranged in the right direction. On the hologram surface
r3, a hologram lens is formed. The first reflecting surface r6 and
the hologram surface r3 form a cuneal shape. On the same surface,
the first reflecting surface r6 includes light-beam-selective
surfaces r4, r2 which selectively perform total-reflection or
transmission in accordance with the incident angles.
[0072] In the left direction of the figure as seen from the lower
end of the prism 1, a pupil 2 is located. The pupil 2 has a pupil
surface r1. The coordinate system is determined in the following
manner. The center of the pupil 2 is defined as the origin of the
coordinate, the forward direction of the pupil 2 (i.e. rightward of
the figure) is defined as the positive of the Z-axis, the upper
direction is defined as the positive of the Y-axis, and the plane
of the drawing is defined as the YZ-surface. And the direction
perpendicularly backward (away from the reader) as seen from the
plane of the drawing is defined as the positive of the X-axis. This
is true also in the following embodiments. Here, in the upper right
direction of the incident surface r7 of the prism 1, an image
display element 3 formed of a transmission-type liquid crystal
display or the like is arranged, and on its front surface serving
as an image display surface r9, an image display member 4 formed of
a flat plate glass is arranged. And its front surface is expressed
as r8.
[0073] As shown in the figure, a light beam L conveying a displayed
image emitted from the image display surface r9 of the image
display element 3 passes through the image display member 4 and
exits from its front surface r8, and then enters the incident
surface r7 of the prism 1. The light beam L having entered the
prism 1 via the incident surface r7 enters the first reflecting
surface r6, and then is reflected (total reflection) here. The
light beam L reflected from the first reflecting surface r6 enters
the second reflecting surface r5 arranged with facing the
reflecting surface r6, and then is reflected (total reflection)
here. The light beam L reflected from the second reflecting surface
r5 enters the light-beam-selective surface r4, and then is
reflected (total reflection) here. The light beam L reflected from
the light-beam-selective surface r4 enters the hologram surface
r3.
[0074] The wavelength of the light beam L corresponds to the
wavelength of the hologram surface r3 in which the diffraction
efficiency of the hologram becomes the highest, and the light beam
L is reflected on the hologram surface r3. The light beam L
reflected on the hologram surface r3 passes through the
light-beam-selective surface r2, and is directed to the pupil
surface r1 of the pupil 2. The hologram on the hologram surface r3
has optical power and functions as an eyepiece optical system that
enlarges the displayed image for being observed. Because of this
property, the light beam L is projected on the observer's pupil
while being enlarged. In addition, as shown in FIGS. 1A and 1B, in
diffractive reflection of a hologram, it is possible to have
reflecting angles different from that of geometric regular
reflection, and this helps make the inclination of the hologram
surface r3 small, and therefore this permits to make the prism 1
thinner.
[0075] In this embodiment, a light-guide portion for directing
light to the hologram surface r3 of the prism 1 is thinly formed by
the construction in which the light beam L is reflected a plurality
of times on the reflecting surfaces arranged with facing each
other, namely the first reflecting surface r6 and the second
reflecting surface r5. In addition, owing to the
light-beam-selective surface for selectively achieving total
reflection or transmission in accordance with the incident angles,
the light beam L is folded in the optical path, and this makes it
possible to output the light beam without separating the optical
path, and this helps realize a construction in which each optical
component is arranged in a compact manner. Furthermore, the
decentered amount of the hologram lens is reduced, and therefore it
is possible to obtain a good displayed image with little
decentering aberration.
[0076] Basically, a hologram exhibits the best wavefront
reproducibility and the highest diffraction efficiency when it is
given the light beam having the same wavelength and angle as the
light beam which formed the hologram. Therefore, it is preferable
that the light beam L emitted from the image display element 3 have
the strongest luminous intensity at the wavelength in which the
hologram lens formed on the hologram surface r3 exhibits the
highest diffraction efficiency.
[0077] For example, when a hologram having the highest diffraction
efficiency at the wavelength around 530 nm and, as the image
display element 3, a non-self illuminating element such as a liquid
crystal display are used, as a light source for illuminating this,
a green LED or the like that has the strongest luminous intensity
at the wavelength around 530 nm is desirable. An LED has the range
of a luminous wavelength of which half-width is 20 to 40 nm, and
therefore when it is used as a light source for emitting image
display light, it is possible to obtain a construction exhibiting
good energy efficiency.
[0078] And, as a light source, it is of course possible to use a
laser that has the same luminous wavelength as the laser used for
forming the hologram. As previously explained in FIG. 5, it is
possible to use a color hologram that has the highest diffraction
efficiency at a plurality of wavelengths.
[0079] FIG. 8 is a vertical sectional view schematically
illustrating the construction of an information display device of a
second embodiment of the present invention. Compare to the first
embodiment, this embodiment adds reflection one time to the
reflection occurring between the reflecting surfaces facing each
other, and an image display member is arranged the observer's pupil
side. Here, when a light beam L passes through a prism 1, the
number of reflection occurring between the surfaces facing each
other is increased one more time and this surface serves as a first
reflecting surface (r5, r7), and a second reflecting surface (r6)
has light-beam-selective surfaces (r2, r4) on the same surface. In
other respects, the construction here is the same as in the first
embodiment.
[0080] FIG. 9 is a vertical sectional view schematically
illustrating the construction of an information display device of a
third embodiment of the present invention. This embodiment is an
example in which, compare to the first embodiment, by arranging
reflecting surfaces (a first and a second reflecting surface)
facing each other with an inclination opening toward an incident
surface of a light beam, an image display member is arranged on
substantially right above a prism 1, and this helps make the entire
optical system thin. Here, as a light-beam-selective surface, third
reflecting surfaces (r2, r4) are arranged in connecting with the
first reflecting surface (r6). A light beam L is transmitted in the
prism 1 in the same manner as the first embodiment.
[0081] FIGS. 10 and 11 are vertical sectional views schematically
illustrating the constructions of information display devices of a
third and a fourth embodiment of the present invention,
respectively. The basic constructions here are the same as the
first and third embodiments, respectively; however, in these
embodiments, by forming reflecting surfaces facing each other as
curved surfaces, a function for correcting aberrations in displayed
images is provided for improving the quality of the images.
Specifically, the curved surfaces are formed as free-form surfaces
(anamorphic aspheric surfaces) for especially aiming at reducing
decentering aberrations.
[0082] FIG. 12 is a vertical sectional view schematically
illustrating the construction of an information display device of a
sixth embodiment of the present invention. In this embodiment, as
an image display element, a reflection-type element such as a
reflection-type liquid crystal display is used, and its
illumination optical system is formed of a part of a prism. An
image display element such as a reflection-type liquid crystal
display needs illumination light to enter from the image display
side thereof, and therefore, here, an illumination light source and
a pupil are so defined as to have a substantially conjugate
relationship for securing bright images with high illumination
efficiency.
[0083] In this figure, an illumination light beam La emitted from a
light source 6 such as an LED enters the prism 1 via an
illumination light incident surface r14, and is reflected from an
illumination reflecting surface r13, and then exits from an exiting
surface r12. And the illumination light beam La enters a front
surface r11 of a condenser lens 5 arranged in front of an image
display member 4, and, through the image display member 4, it
enters an image display element 3. Here, the illumination light
beam is modulated into an image light beam, and the image light
beam is reflected and exits from a display surface r10.
[0084] The light beam L of the displayed image exited from the
display surface r10 of the image display element 3 passes through
the image display member 4 and exits from its front surface r9.
Then, the light beam L passes through the condenser lens 5 and
exits from its front surface r8, and enters an incident surface r7
of the prism 1. After that, the light beam L is transmitted in the
prism 1 in the same manner as the first embodiment. In this
embodiment, the exiting surface r12 and the incident surface r7 of
the prism 1 are the identical, and the front surface r11 and the
front surface r8 of the condenser lens are the identical,
respectively.
[0085] In the illumination optical system of this embodiment, near
the prism 1, a surface that conjugates with a pupil 2 is formed of
the condenser lens 5 that is a convex lens and the illumination
reflecting surface r13 that is a concave mirror, and by arranging
the light source 6 on the surface, the illumination optical system
having a high illumination efficiency is obtained. This makes it
possible to observe a bright image while making best use of
illumination light amount. Thus, by forming an illumination optical
system in a part of a prism, it helps make the entire optical
system compact.
[0086] FIG. 13 is a vertical sectional view schematically
illustrating the construction of an information display device of a
seventh embodiment of the present invention. This embodiment is an
example in which a prism serving as a deflection correction member
is applied to the construction of the first embodiment. In the
first embodiment (also the second and sixth embodiments), the
reflecting surfaces facing each other (the first and second
reflecting surfaces) are arranged parallel to each other, and
therefore this portion can transmit the external light traveling
from the positive or negative direction of the Z-axis without
distorting it and direct it to a pupil 2. However, for reducing the
decentering amount of the hologram, the hologram surface r3 and the
light-beam-selective surface are arranged not parallel but in an
inclined state.
[0087] In other words, because the hologram surface r3 is obliquely
arranged in the lower portion of the prism 1, the lower portion of
the prism 1 forms a cuneal shape, and the external light passing
through this portion exits therefrom in a full-size but with being
deflected. Therefore, as shown in FIG. 13, this embodiment is
provided with a deflection correction member 7 which is a prism
that has an inclined surface 7a arranged in uniting with the
hologram surface r3 or parallel to the hologram surface r3 with a
slight space in between, and that has surfaces 7b, 7c that are
identical to the extension surfaces of the first and second
reflecting surfaces. Owing to this, deflection of the external
light is corrected, and this makes it possible to observe the
external light in a natural manner. The hologram surface r3 is
flat, and therefore it is easy to form a holographic photosensitive
material and it does not require high position accuracy in
connecting the inclined surface 7a of the deflection correction
member 7, and this makes it possible to attach the deflection
correction member 7 to the prism 1 readily.
[0088] And, as described so far, reflection occurring between the
surfaces facing each other is total reflection and external light
is not intercepted, and therefore it is possible to obtain a wide
external observed area. In the above-mentioned condition, the
hologram surface r3 functions as a combiner. In other words,
because a reflection-type hologram like the hologram surface r3
affects only light having a specific wavelength (diffractive
wavelength), as explained in FIG. 4 previously, it is possible to
perform see-through type information display in which an observer
observes external light and image light while superimposing them.
As explained in FIG. 5 previously, this is true also to a color
hologram. As this embodiment, the construction with which a
deflection correction member is provided is also applicable to the
second and sixth embodiments.
[0089] FIG. 14 is a vertical sectional view schematically
illustrating the construction of an information display device of
an eighth embodiment of the present invention. In this figure, the
upper part of an optical system corresponds to the upper part of an
image display area and the lower part of the optical system
corresponds to the lower part of the image display area. And the
individual optical systems are arranged in perpendicularly
symmetric (longitudinal direction on the plane of the drawing) with
respect to the center of a pupil, i.e. the center of the image
display area. Therefore, in the following explanation and the
construction data described latter, the whole system is represented
by the upper part of the optical system. This is true also in the
following embodiments.
[0090] In this figure, a prism 1 has a plate-like form with
obliquely spreading in the upper right direction, and its upper end
surface is an incident surface r7. And, on the left and right of
the figure, it has a first reflecting surface r6 and a second
reflecting surface r5 that face each other with being arranged
substantially parallel to each other. And, on the lower end of the
prism 1, a concave reflecting surface r3 is arranged with inclining
to a light beam incident surface of the prism. Owing to this, it is
so constructed that the two optical systems in the upper and lower
parts do not overlap each other. And the first reflecting surface
r6 and the concave reflecting surface r3 form a cuneal shape. On
the same surface, the first reflecting surface r6 has a
light-beam-selective surfaces r4, r2 which selectively perform
total-reflection or transmission in accordance with the incident
angles of a light beam.
[0091] In the left direction of the figure as seen from the lower
end of the prism 1, a pupil 2 is located. The coordinate system is
determined in the following manner. The center of the pupil 2 is
defined as the origin of the coordinate, the forward direction
(i.e. rightward of the figure) is defined as the positive of the
Z-axis, the upper direction is defined as the positive of the
Y-axis, and the plane of the drawing is defined as the YZ-surface.
And the direction perpendicularly backward (away from the reader)
as seen from the plane of the drawing is defined as the positive of
the X-axis. This is true also in the following embodiments. Here,
in the right upper direction of the incident surface r7 of the
prism 1, an image display element 3 formed of a transmission-type
liquid crystal display or the like is arranged, and a display
surface that is also a front surface of the image display element 3
is expressed as r8.
[0092] As shown in the figure, a light beam L emitted from the
display surface r8 of the image display element 3 enters the
incident surface r7 of the prism 1. The light beam L having entered
the prism 1 via the incident surface r7 enters the first reflecting
surface r6, and then is reflected (total reflection) here. The
light beam L reflected from the first reflecting surface r6 enters
the second reflecting surface r5 arranged with facing the
reflecting surface r6, and then is reflected (total reflection)
here. The light beam L reflected from the second reflecting surface
r5 enters the light-beam-selective surface r4, and then is
reflected (total reflection) here. The light beam L reflected from
the light-beam-selective surface r4 enters the concave reflecting
surface r3.
[0093] In this embodiment, the concave reflecting surface is
obliquely arranged relative to a light beam of the displayed image
and has optical power as an eyepiece optical system, and therefore
it forms a nonaxismmetric optical system. When this nonaxismmetric
optical system performs only the same function-as that of a
centered lens, asymmetrical distortion (trapezoid distortion)
caused by decentering or curvature of image surface occur. In order
to prevent this, it is preferable that the concave reflecting
surface be provided with not only rotationally symmetrical
wavefront reproducibility but also free-form surface wavefront
reproducibility. Therefore, such a concave reflecting surface is
formed as an anamorphic aspheric surface and best suited for
correcting decentering aberrations.
[0094] In this embodiment, a light-guide portion for directing
light to the concave reflecting surface r3 of the prism 1 is thinly
formed by the construction in which the light beam L is reflected a
plurality of times on the reflecting surfaces arranged with facing
each other, namely the first reflecting surface r6 and the second
reflecting surface r5. In addition, owing to the
light-beam-selective surface for selectively achieving total
reflection or transmission in accordance with the incident angles,
the light beam L is folded in the optical path, and this makes it
possible to output the light beam without separating the optical
path, and this helps realize a construction in which each optical
component is arranged in a compact manner. Furthermore, the
decentered amount of the concave reflecting surface is reduced, and
therefore it is possible to obtain a satisfactory displayed image
with little decentering aberration.
[0095] Note that, this embodiment is so constructed that the
individual displayed images displayed on the upper and lower image
display elements 3 are perfectly independent with being separated
into the upper and lower directions from the center of the image
display area; however, it is possible to extend each image display
element 3 and to make the individual image display areas overlap
each other. This makes it possible to eliminate part lack of the
diameter of a pupil in the center of the image display area. And,
by using the concave reflecting surface as a half mirror, for
example, for partly reflecting a light beam, and by arranging a
deflection correction member for correcting deflection of external
light, it is possible to perform see-through type information
display in which an observer observes external light and image
light with superimposing them. Hereinafter, this will be
explained.
[0096] In this embodiment, reflecting surfaces (a first and a
second reflecting surface) facing each other are arranged parallel
to each other, and the individual reflecting surfaces of the upper
and lower parts of prism 1 are arranged on the same surfaces,
respectively. In the prism 1, reflection of the light beam emitted
from the displayed image is performed as total reflection, and the
reflection coating is not applied to the reflecting surfaces.
Therefore, this portion can transmit the external light traveling
from the positive or negative direction of the Z-axis without
distorting it and direct it to the pupil 2. However, in order to
make the light-beam-selective surface have light-beam-selectivity
for selectively performing total reflection or transmission in
accordance with the incident angles of a light beam, the concave
reflecting surface r3 and the light-beam-selective surface are
arranged not parallel but in an inclined state.
[0097] In other words, in the upper part of the prism 1, for
example, because the concave reflecting surface r3 is obliquely
arranged in a lower portion of the upper part of the prism 1, the
lower portion of the upper part of the prism 1 forms a cuneal
shape, and the external light passing through this portion exits
therefrom with being deflected. In addition, because it is
transmitted through the concave surface, the light is affected by
its optical power, and therefore a satisfactory see-through
function is not secured. Therefore, as shown in FIG. 14, this
embodiment is provided with a deflection correction member 14 which
is a prism that has an inclined surface 14a arranged in uniting
with the concave reflecting surface r3 or parallel to the concave
reflecting surface r3 with a slight space in between, and that has
a surface 14b which is identical to the extension surface of the
second reflecting surface. Owing to this, deflection of external
light is corrected, and this makes it possible to observe external
light in a natural manner.
[0098] FIG. 15 is a vertical sectional view schematically
illustrating the construction of an information display device of a
ninth embodiment of the present invention. This embodiment is an
example in which, compare to the eighth embodiment, by arranging
reflecting surfaces (a first and a second reflecting surface)
facing each other with an inclination opening toward an incident
surface of a light beam, an image display member is arranged on
substantially right above a prism 1, and this helps make the entire
optical system thin. The light beam L is transmitted in the prism 1
in the same manner as the eighth embodiment.
[0099] FIG. 16 is a vertical sectional view schematically
illustrating the construction of an information display device of a
tenth embodiment of the present invention. The basic construction
here is the same as the eighth and ninth embodiments; however, in
this embodiment, by forming reflecting surfaces facing each other
as curved surfaces, a function for correcting aberrations in
displayed images are added for improving the quality of the images.
Specifically, the curved surfaces are formed as curved surfaces
rotationally symmetrical about the center of a pupil. When it is so
constructed as to perform see-through observation of an external
image, by making the prism 1 function as a lens element with using
the power of this curved surfaces and by adding a diopter
correction function to the prism 1, it is also possible to use this
apparatus as conventional spectacles.
[0100] FIG. 17 is a vertical sectional view schematically
illustrating the construction of an information display device of
an eleventh embodiment of the present invention. The basic
construction here is the same as the eighth embodiment; however, in
this embodiment, the reflecting surface is not a concave reflecting
surface but a hologram surface. Although a hologram is formed as a
flat surface, it can have optical power, and therefore when it is
given a see-through function, through its diffractive reflection,
it functions as a lens element and affects the light beam traveled
from the displayed image, and it does not affect external light,
and thereby it is possible to observe an external image in a
natural manner. Note that, as for a hologram to be used, for
obtaining high diffraction efficiency and a bright displayed image
and external image, it is preferable that the hologram be
reflection type and among which a so-called volume hologram having
a certain thickness, at the same time, a phase hologram exhibiting
low absorbency of light is best suited.
[0101] In this figure, the wavelength of the light beam L emitted
from the displayed image is substantially identical to the
wavelength of the hologram surface r3 at which the diffraction
efficiency of a hologram lens becomes the highest, and the light
beam L is reflected on the hologram surface r3. The light beam L
reflected on the hologram surface r3 passes through a
light-beam-selective surface r2, and is directed to a pupil surface
r1 of a pupil 2. The hologram lens on the hologram surface r3 has
optical power and functions as an eyepiece optical system that
enlarges a displayed image to be observed. Because of this
property, the light beam L is projected on the observer's pupil
while being enlarged.
[0102] Here, by making a single hologram have an eyepiece optical
function, it is possible to realize a simple construction. The
hologram surface r3 is flat, and therefore it is easy to form a
holographic photosensitive material and it does not require high
position accuracy in connecting an inclined surface 14a of a
deflection correction member 14, and this makes it possible to
attach the deflection correction member 14 to the prism 1
readily.
[0103] Basically, a hologram exhibits the best wavefront
reproducibility and the highest diffraction efficiency when it is
given the light beam having the same wavelength and angle as the
light beam which formed the hologram. Therefore, it is preferable
that the light beam L emitted from the image display element 3 have
the strongest luminous intensity at the wavelength in which the
hologram lens formed on the hologram surface r3 exhibits the
highest diffraction efficiency.
[0104] For example, when a hologram having the highest diffraction
efficiency at the wavelength around 530 nm and, as the image
display element 3, a non-self illuminating element such as a liquid
crystal display are used, as a light source for illuminating this,
a green LED or the like that has the strongest luminous intensity
at the wavelength around 530 nm is desirable. An LED has the range
of luminous wavelength of which half-width is 20 to 40 nm, and
therefore when it is used as a light source for emitting image
display light, it is possible to obtain a construction exhibiting
good energy efficiency.
[0105] And, as a light source, it is of course possible to use a
laser that has the same wavelength as the laser used for forming
the hologram. As previously explained in FIG. 5, it is also
possible to use a color hologram that has the highest diffraction
efficiency at a plurality of wavelengths. As explained in FIG. 4, a
reflection-type hologram affects only light having a specific
wavelength (diffractive wavelength), and therefore it does not
reflect but transmits light having wavelengths other than a
diffractive wavelength. Because of this property, compare to the
eighth embodiment, the eleventh embodiment employing a hologram, it
is possible to perform better see-through type information display.
This is true also to a color hologram.
[0106] FIG. 18 is a vertical sectional view schematically
illustrating the construction of an information display device of a
twelfth embodiment of the present invention. This embodiment is an
example in which, compare to the eleventh embodiment, by arranging
reflecting surfaces (a first and a second reflecting surface)
facing each other with an inclination opening toward an incident
surface of a light beam, an image display member is arranged on
substantially right above a prism 1, and this helps make the entire
optical system thin. The light beam L is transmitted in the prism 1
in the same manner as the eleventh embodiment.
[0107] FIGS. 19 and 20 are vertical sectional views schematically
illustrating the constructions of information display devices of a
thirteenth and a fourteenth embodiment of the present invention.
The basic construction here is the same as the ninth and twelfth
embodiments; however, in this embodiment, by arranging a deflection
correction member for correcting deflection of external light, it
is possible to perform see-through type information display in
which an observer observes external light and image light with
superimposing them. Hereinafter, this will be explained.
[0108] In the ninth and twelfth embodiments, by arranging the
reflecting surfaces (a first and a second reflecting surface)
facing each other with an inclination opening toward an incident
surface of a light beam, the image display member is arranged on
substantially right above the prism 1, and this helps make the
entire optical system thin. In addition, for making the
light-beam-selective surface have light beam selectivity that
selectively performs total reflection or transmission in accordance
with the incident angles of a light beam, the concave reflecting
surface r3 or the hologram surface, and the light-beam-selective
surface are arranged not parallel but in an inclined state.
[0109] In other words, in the upper part of the prism 1, for
example, because the second reflecting surface r5 and the concave
reflecting surface or the hologram surface r3 are obliquely
arranged in the prism 1, the lower portion of the upper part of the
prism 1 forms a cuneal shape, and the external light passing
through this portion exits therefrom with being deflected. In
addition, because it is transmitted through the concave surface,
the light is affected by its optical power, and therefore a
satisfactory see-through function is not secured.
[0110] Therefore, as shown in FIG. 19, the thirteenth embodiment is
provided with a deflection correction member 7 which is a prism
that has inclined surfaces 7a and 7b arranged in uniting with a
second reflecting surface r5 and a concave reflecting surface r3 or
parallel to them with a slight space in between, and that has a
surface 7c that is parallel to a first reflecting surface. And, as
shown in FIG. 20, the fourteenth embodiment is provided with a
deflection correction member 7 which is a prism that has inclined
surfaces 7a and 7b arranged in uniting with a second reflecting
surface r5 and a hologram surface r3 or parallel to them with a
slight space in between, and that has a surface 7c that is parallel
to a first reflecting surface. Owing to this, deflection of
external light is corrected, and this makes it possible to observe
the external light in a natural manner.
[0111] FIG. 21 is a diagram showing an outlook of a head-mounted
image display apparatus employing the present invention. As
previously described, the information display device of the present
invention can be thinly constructed, and therefore, as shown in
this figure, it is possible to realize an image display apparatus
having a spectacles shape. Here, to the portion corresponding to
the spectacle lenses, a prism 1 and a deflection correction member
7 are fitted, and an illumination optical system 8 is arranged
above of them.
[0112] From the end of a flame 9, a code 10 extends and is
connected to a not shown movable personal computer or a portable
telephone so as to receive an image information therefrom. It is
also possible to realize a wireless apparatus, if it is used in a
close range. Because of the property of a hologram described
earlier, it is possible to secure a high see-through function, and
therefore this apparatus serves as an HMD (head mounted display)
which unlikely to cause a user to be fatigued and is wearable all
the time. This is also best suited for an image display apparatus
for use in a so-called wearable computer.
[0113] FIG. 22 is a vertical sectional view illustrating the
information display device of the image display apparatus employed
in the head-mounted image display apparatus described above. In
other words, this is a sectional view taken on line C-C of FIG. 21.
As shown in this figure, light emitted from a light source 6
composed of an LED or the like in an illumination optical system 8
passes through a condenser lens 5 and illuminates an image display
element 3. Here, the light is modulated and exits therefrom as
image light, and is transmitted in a prism 1 after passing through
an image display member 4, and then is reflected from a hologram
surface r3 and reaches a pupil 2. In this structure, it is possible
to perform see-through observation of an external image through the
prism 1 and a deflection correction member 7. If the prism 1 and
the deflection correction member 7 are made to serve as a lens
element and provided with a diopter correction function, it is also
possible to use it as conventional spectacles.
[0114] FIG. 23 is a diagram illustrating an outlook of another
example of a head-mounted image display apparatus employing the
present invention. Here, to the portion corresponding to the
spectacle lenses, a prism 1 and a deflection correction member 14
(or 7) are fitted, and an illumination optical system 8 is arranged
above or below of them.
[0115] From the end of a flame 9, a code 10 extends and is
connected to a not shown movable personal computer or a portable
telephone so as to receive an image information therefrom. It is
also possible to realize a wireless apparatus, if it is used in a
close range. Because of the property of a hologram described
earlier, it is possible to secure a high see-through function, and
therefore this apparatus serves as an HMD (head mounted display)
which unlikely to cause a user to be fatigued and is wearable all
the time. This is best suited for an image display apparatus for
use in a so-called wearable computer.
[0116] FIG. 24 is a vertical sectional view illustrating the
information display device of the image display apparatus employed
in the head-mounted image display apparatus described above. In
other words, this is a sectional view taken on line E-E of FIG. 23.
As shown in this figure, light emitted from a light source 6
composed of an LED or the like in an illumination optical system 8
passes through a condenser lens 5 and illuminates an image display
element 3. Here, the light is modulated and exits therefrom as
image light, and is transmitted in a prism 1, and then is reflected
from a concave reflecting surface or a hologram surface r3 and
reaches a pupil 2. In this structure, it is possible to perform
see-through observation of an external image through the prism 1
and a deflection correction member 14. If the prism 1 and the
deflection correction member 14 are made to serve as a lens element
and provided with a diopter correction function, it is also
possible to use it as conventional spectacles.
[0117] FIG. 25 is a diagram illustrating an outlook of an example
applying the present invention to a portable telephone. Because it
is possible to thinly construct the information display device of
the present invention, as shown in this figure, it is possible to
realize an image display device integrated in a flipper of a
portable telephone. Here, in the flipper 12 which is rotatable with
being pivoted on the main body 11 of the portable telephone, the
information display device of the present invention is integrated,
and the displayed image is observed through an observation window
13. Owing to this, it is possible to display a fine image having a
wide field of view that is not obtainable by a conventional image
display surface of a portable telephone.
[0118] The entire system from an illumination optical system to an
eyepiece optical system is integrated in the flipper 12, and the
arrangement of the individual optical systems are not changed by
opening or closing the flipper 12, and thereby there is little
chance for error. As described above, it is possible to integrate
the information display device of the present invention in a
conventional portable telephone without largely modifying the
structure thereof, and this makes it possible to realize an image
display apparatus having excellent portability.
[0119] FIG. 26 is a vertical sectional view illustrating the
information display device of the image display apparatus
integrated in the flipper 12 of a portable telephone as described
above. In other words, this is a sectional view taken on line D-D
of FIG. 25. As shown in this figure, light emitted from a light
source 6 composed of an LED or the like in an illumination optical
system 8 illuminates an image display element 3. Here, the light is
modulated and exits therefrom as image light, and is transmitted in
a prism 1 after passing through an image display member 4, and then
is reflected from a hologram surface r3 and reaches a pupil 2
through an observation window 13.
[0120] Now, the optical constructions of the present invention will
be described in more detail with reference to the construction
data. The examples 1 to 6 described latter correspond to the first
to sixth embodiments described above, and the examples 7 to 11
correspond to the eighth to twelfth embodiments described above.
And all the holograms used in the examples of the invention have
both a manufacturing wavelength (recording wavelength) and a using
wavelength of 532 nm, and they are of the first-order usage. And
the configuration data of each surface is expressed as a global
coordinate system with having its origin at the center of pupil
surface. The directions of the X-, Y- and Z-axis are as explained
in FIGS. 7 and 14. And the locations of the individual surfaces are
expressed as XSC, YSC, and ZSC, respectively. Here, the unit is mm.
And the inclinations of the individual surfaces, when the X-, Y-
and Z-axis function as the rotation axes, are expresses as ASC,
BSC, and CSC. Here, the unit is degree.
[0121] As for a definition of the hologram surface, by defining the
two light beams used for forming the hologram, the hologram
surfaces are univocally defined. The two light beams are defined
depend on the positions of the light sources of the individual
light beams and the light beams emitted from the individual light
sources is either a focusing beam (VIA) or an emitting beam (REA).
The coordinates of a first point light source (HV1) and a second
point light source (HV2) are expressed as (HX1, HY1, HZ1) and (HX2,
HY2, HZ2), respectively.
[0122] In the individual embodiments, wavefront reproduction is
performed by using a complicated hologram, and therefore, in
addition to the definition of the two light beams, the hologram
surface is defined by direction cosine of an exiting light beam
relative to an incident light beam determined by the phase function
.phi.. As indicated in the following formula, the phase function
.phi. is a generator polynomial at the hologram surface's position
(X, Y), and is expressed as monomials having coefficients from the
first to the tenth and arranged in a ascending order. In the
construction data, the coefficients C.sub.j of the phase function
.phi. are indicated.
.phi.=C.sub.1X+C.sub.2Y+C.sub.3X.sup.2+C.sub.4XY+C.sub.5Y.sup.2+.multidot.-
.multidot..multidot.C.sub.65Y.sup.10
[0123] Note that, when the indices of X, Y are expressed as m, n,
the number j of the coefficient C.sub.j is given by the formula
below.
j={(m+n).sup.2+m+3n}/2
[0124] wherein the direction cosine of an exiting light beam
relative to the X-, Y- and Z-axis are given by the formulae below.
1 l ' = l + 0 m ' = m + y 0 n ' = l + 1 - l ' 2 - m ' 2
[0125] where
[0126] l', m', and n' are the vectors of the direction of the
normal to the exiting light beams, respectively;
[0127] l, m, and n are the vectors of the direction of the normal
to the incident light beams, respectively;
[0128] .lambda. represents the wavelength of a reproduced light
beam; and
[0129] .lambda.0 represents the wavelength of the light beam
forming a hologram.
[0130] In the construction data, the parameters relative to the
anamorphic aspheric surface regulate the sag Z (unit: mm) in the
direction of the Z- axis defined by the following formula when the
points of intersection between the individual surfaces and their
optical axes are defined as the origins, and the optical axis is
expressed as the Z-axis. And the radius of curvature in the data is
the radius of curvature in the direction of the Y-axis, and RDX is
the radius of curvature in the direction of the X-axis.
Z=(CUX.multidot.X.sup.2+CUY.multidot.Y.sup.2)/[1+{1-(1+KX).multidot.CUX.su-
p.2.multidot.X.sup.2-(1+KY).multidot.CUY.sup.2.multidot.Y.sup.2}.sup.1/2]+-
AR.multidot.{(1-AP).multidot.X.sup.2+(1+AP).multidot.Y.sup.2}.sup.2+BR.mul-
tidot.{(1-BP).multidot.X.sup.2+(1+BP).multidot.Y.sup.2}.sup.3+CR.multidot.-
{(1-CP).multidot.X.sup.2+(1+CP).multidot.Y.sup.2}.sup.4
[0131] wherein
[0132] CUX and CUY represent the curvatures in the directions of
the X- and Y-axes, respectively.
1TABLE 1 Practical Example 1 Radius of Surface No. Curvature Medium
r1 (Pupil) INFINITY AIR r2 (Light-Beam-Selective Surface) INFINITY
PMMA r3 (Hologram Surface) INFINITY Reflecting Surface Definitions
of the two light beams HV1: REA HV2: VIR HX1: 0.000000 .times.
10.sup.+0 HY1: -0.930000 .times. 10.sup.+1 HZ1: -0.195000 .times.
10.sup.+2 HX2: 0.000000 .times. 10.sup.-0 HY2: 0.162516 .times.
10.sup.-6 HZ2: -0.100000 .times. 10.sup.+9 HWL: 532 Phase
Coefficient C2: 6.8824 .times. 10.sup.-1 C3: -1.1420 .times.
10.sup.-3 C5: 3.4189 .times. 10.sup.-3 C7: -4.0580 .times.
10.sup.-4 C9: 9.1503 .times. 10.sup.-4 C10: -4.4137 .times.
10.sup.-5 C12: 9.0177 .times. 10.sup.-5 C14: -2.5540 .times.
10.sup.-3 C16: 1.0035 .times. 10.sup.-5 C18: -1.7171 .times.
10.sup.-4 C20: 2.0701 .times. 10.sup.-3 C21: 2.6206 .times.
10.sup.-6 C23: -6.2010 .times. 10.sup.-7 C25: 9.8207 .times.
10.sup.-5 C27: -8.9847 .times. 10.sup.-4 C29: -1.0997 .times.
10.sup.-6 C31: 5.4344 .times. 10.sup.-6 C33: -3.0341 .times.
10.sup.-5 C35: 2.2812 .times. 10.sup.-4 C36: -6.8962 .times.
10.sup.-8 C38: -2.1492 .times. 10.sup.-7 C40: -2.6430 .times.
10.sup.-6 C42: 5.7609 .times. 10.sup.-6 C44: -3.3908 .times.
10.sup.-5 C46: 3.8118 .times. 10.sup.-8 C48: 1.0893 .times.
10.sup.-7 C50: 4.2909 .times. 10.sup.-7 C52: -6.2777 .times.
10.sup.-7 C54: 2.7298 .times. 10.sup.-6 C55: 2.4769 .times.
10.sup.-10 C57: -5.5383 .times. 10.sup.-9 C59: -7.9873 .times.
10.sup.-9 C61: -2.3844 .times. 10.sup.-8 C63: 2.9452 .times.
10.sup.-8 C65: -9.1747 .times. 10.sup.-8 r4 (Light-Beam-Selective
Surface) INFINITY Reflecting Surface r5 (Second Reflecting Surface)
INFINITY Reflecting Surface r6 (First Reflecting Surface) INFINITY
Reflecting Surface r7 (Incident Surface) INFINITY AIR r8 (Image
Display Member) INFINITY BK7 r9 (Display Surface) INFINITY
Configuration of Each Surface Surface XSC YSC ZSC ASC BSC CSC r1 0
0 0 0 0 0 r2 0 -4 14 2 0 0 r3 0 -3.5 14.52 -26 0 0 r4 0 -4 14 2 0 0
r5 0 1.6 17.2 2 0 0 r6 0 -4 14 2 0 0 r7 0 18.5 16.274 92 0 0 r8 0
22.624 18.559 54.146 0 0 r9 0 23.272 19.028 54.146 0 0
[0133]
2TABLE 2 Practical Example 2 Radius of Surface No. Curvature Medium
r1 (Pupil) INFINITY AIR r2 (Light-Beam-Selective Surface) INFINITY
PMMA r3 (Hologram Surface) INFINITY Reflecting Surface Definitions
of the two light beams HV1: REA HV2: VIR HX1: 0.000000 .times.
10.sup.+0 HY1: 0.000000 .times. 10.sup.+0 HZ1: 0.000000 .times.
10.sup.+0 HX2: 0.000000 .times. 10.sup.+0 HY2: 0.000000 .times.
10.sup.+0 HZ2: 0.000000 .times. 10.sup.+0 HWL: 532 Phase
Coefficient C2: 2.6330 .times. 10.sup.-1 C3: -1.9347 .times.
10.sup.-2 C5: -1.1701 .times. 10.sup.-2 C7: 3.5433 .times.
10.sup.-5 C9: 1.5459 .times. 10.sup.-3 C10: -2.3974 .times.
10.sup.-5 C12: 6.9740 .times. 10.sup.-5 C14: -2.5481 .times.
10.sup.-3 C16: 8.8403 .times. 10.sup.-6 C18: -1.0732 .times.
10.sup.-4 C20: 2.0558 .times. 10.sup.-3 C21: 2.2541 .times.
10.sup.-6 C23: -2.2649 .times. 10.sup.-6 C25: 6.7359 .times.
10.sup.-5 C27: -9.1221 .times. 10.sup.-4 C29: -5.6362 .times.
10.sup.-7 C31: 3.0260 .times. 10.sup.-6 C33: -2.2099 .times.
10.sup.-5 C35: 2.3860 .times. 10.sup.-4 C36: -7.7663 .times.
10.sup.-8 C38: -3.7407 .times. 10.sup.-8 C40: -1.5800 .times.
10.sup.-6 C42: 4.2657 .times. 10.sup.-6 C44: -3.6746 .times.
10.sup.-5 C46: 1.4380 .times. 10.sup.-8 C48: 4.9339 .times.
10.sup.-8 C50: 2.9537 .times. 10.sup.-7 C52: -4.6725 .times.
10.sup.-7 C54: 3.0856 .times. 10.sup.-6 C55: 8.7525 .times.
10.sup.-10 C57: -2.3972 .times. 10.sup.-9 C59: -4.9346 .times.
10.sup.-9 C61: -1.8629 .times. 10.sup.-8 C63: 2.2286 .times.
10.sup.-8 C65: -1.0907 .times. 10.sup.-7 r4 (Light-Beam-Selective
Surface) INFINITY Reflecting Surface r5 (First Reflecting Surface)
INFINITY Reflecting Surface r6 (Second Reflecting Surface) INFINITY
Reflecting Surface r7 (First Reflecting Surface) INFINITY
Reflecting Surface r8 (Incident Surface) INFINITY AIR r9 (Image
Display Member) INFINITY BK7 r10 (Display Surface) INFINITY
Configuration of Each Surface Surface XSC YSC ZSC ASC BSC CSC r1 0
0 0 0 0 0 r2 0 -4 14 2 0 0 r3 0 -3.5 14.52 -26 0 0 r4 0 -4 14 2 0 0
r5 0 1.6 17.2 2 0 0 r6 0 -4 14 2 0 0 r7 0 1.6 17.2 2 0 0 r8 0
26.173 17.367 85.959 0 0 r9 0 29.819 10.670 123.868 0 0 r10 0
30.483 10.224 123.868 0 0
[0134]
3TABLE 3 Practical Example 3 Radius of Surface No. Curvature Medium
r1 (Pupil) INFINITY AIR r2 (Light-Beam-Selective Surface) INFINITY
PMMA r3 (Hologram Surface) INFINITY Reflecting Surface Definitions
of the two light beams HV1: REA HV2: VIR HX1: 0.000000 .times.
10.sup.+0 HY1: -0.930000 .times. 10.sup.+1 HZ1: -0.195000 .times.
10.sup.+2 HX2: 0.000000 .times. 10.sup.+0 HY2: 0.162518 .times.
10.sup.+6 HZ2: -0.100000 .times. 10.sup.+9 HWL: 532 Phase
Coefficient C2: 6.8432 .times. 10.sup.-1 C3: -9.5823 .times.
10.sup.-5 C5: 2.2687 .times. 10.sup.-3 C7: -4.4443 .times.
10.sup.-4 C9: 2.2032 .times. 10.sup.-3 C10: -7.5545 .times.
10.sup.-5 C12: 2.5738 .times. 10.sup.-4 C14: -4.0800 .times.
10.sup.-3 C16: 2.3576 .times. 10.sup.-5 C18: -3.8193 .times.
10.sup.-4 C20: 2.8456 .times. 10.sup.-3 C21: 5.0913 .times.
10.sup.-6 C23: -8.1124 .times. 10.sup.-6 C25: 2.2428 .times.
10.sup.-4 C27: -1.0916 .times. 10.sup.-3 C29: -1.9638 .times.
10.sup.-6 C31: 1.2774 .times. 10.sup.-5 C33: -7.4305 .times.
10.sup.-5 C35: 2.4590 .times. 10.sup.-4 C36: -1.3905 .times.
10.sup.-7 C38: -2.6899 .times. 10.sup.-7 C40: -5.6310 .times.
10.sup.-6 C42: 1.5023 .times. 10.sup.-5 C44: -3.2193 .times.
10.sup.-5 C46: 6.3049 .times. 10.sup.-8 C48: 1.6803 .times.
10.sup.-7 C50: 9.2358 .times. 10.sup.-7 C52: -1.7072 .times.
10.sup.-6 C54: 2.2437 .times. 10.sup.-6 C55: 8.2683 .times.
10.sup.-10 C57: -9.9422 .times. 10.sup.-9 C59: -1.1891 .times.
10.sup.-8 C61: -5.3729 .times. 10.sup.-8 C63: 8.2292 .times.
10.sup.-8 C65: -6.3340 .times. 10.sup.-8 r4 (Light-Beam-Selective
Surface) INFINITY Reflecting Surface r5 (Second Reflecting Surface)
INFINITY Reflecting Surface r6 (First Reflecting Surface) INFINITY
Reflecting Surface r7 (Incident Surface) INFINITY AIR r8 (Image
Display Member) INFINITY BK7 r9 (Display Surface) INFINITY
Configuration of Each Surface Surface XSC YSC ZSC ASC BSC CSC r1 0
0 0 0 0 0 r2 0 -4 14 2 0 0 r3 0 -3.5 14.52 -26 0 0 r4 0 -4 14 2 0 0
r5 0 1.6 17.2 0 0 0 r6 0 7.440 13.601 8 0 0 r7 0 8.446 -49.727
103.314 0 0 r8 0 26.186 13.609 73.060 0 0 r9 0 26.952 13.842 73.060
0 0
[0135]
4TABLE 4 Practical Example 4 Radius of Surface No Curvature Medium
r1 (Pupil) INFINITY AIR r2 (Light-Beam-Selective Surface) 521.799
PMMA Anamorphic Aspherical Surface KY: 0.000000 KX: 0.000000 RDX:
1624.78 AR: -0.904617 .times. 10.sup.-6 BR: 0.545631 .times.
10.sup.-9 CR: 0.242759 .times. 10.sup.-11 AP: 0.000000 .times.
10.sup.+0 BP: 0.000000 .times. 10.sup.+0 CP: 0.000000 .times.
10.sup.+0 r3 (Hologram Surface) INFINITY Reflecting Surface
Definitions of the two light beams HV1: REA HV2: VIR HX1: 0.000000
.times. 10.sup.+0 HY1: -0.930000 .times. 10.sup.+1 HZ1: -0.195000
.times. 10.sup.+2 HX2: 0.000000 .times. 10.sup.+0 HY2: 0.162516
.times. 10.sup.+6 HZ2: -0.100000 .times. 10.sup.+9 HWL: 532 Phase
Coefficient C2: 6.8873 .times. 10.sup.-1 C3: -4.1293 .times.
10.sup.-3 C5: 2.3958 .times. 10.sup.-3 C7: -5.5767 .times.
10.sup.-4 C9: 7.1611 .times. 10.sup.-4 C10: -3.6017 .times.
10.sup.-5 C12: 2.7273 .times. 10.sup.-5 C14: -2.3152 .times.
10.sup.-3 C16: 1.1177 .times. 10.sup.-5 C18: -1.0588 .times.
10.sup.-4 C20: 1.8914 .times. 10.sup.-3 C21: 1.5599 .times.
10.sup.-6 C23: -2.4275 .times. 10.sup.-6 C25: 6.9042 .times.
10.sup.-5 C27: -8.5536 .times. 10.sup.-4 C29: -8.1008 .times.
10.sup.-7 C31: 2.9542 .times. 10.sup.-6 C33: -2.3916 .times.
10.sup.-5 C35: 2.2816 .times. 10.sup.-4 C36: -4.5807.times.
10.sup.-8 C38: 4.6875 .times. 10.sup.-9 C40: -1.5252 .times.
10.sup.-6 C42: 4.8016 .times. 10.sup.-6 C44: -3.5890 .times.
10.sup.-5 C46: 1.9992 .times. 10.sup.-8 C48: 4.5134 .times.
10.sup.-8 C50: 2.8065 .times. 10.sup.-7 C52: -5.3410 .times.
10.sup.-7 C54: 3.0835 .times. 10.sup.-6 C55: 3.6847 .times.
10.sup.-10 C57: -3.2688 .times. 10.sup.-9 C59: -4.0812 .times.
10.sup.-9 C61: -1.7726 .times. 10.sup.-8 C63: 2.5477 .times.
10.sup.-8 C65: -1.1167 .times. 10.sup.-7 r4 (Light-Beam-Selective
Surface) 521.799 Reflecting Surface (Anamorphic Aspherical Surface)
KY: 0.000000 KX: 0.000000 RDX: 1624.78 AR: -0.904617 .times.
10.sup.-6 BR: 0.545631 .times. 10.sup.-9 CR: 0.242759 .times.
10.sup.-11 AP: 0.000000 .times. 10.sup.+0 BP: 0.000000 .times.
10.sup.+0 CP: 0.000000 .times. 10.sup.+0 r5 (Second Reflecting
Surface) 212.709 Reflecting Surface (Anamorphic Aspherical Surface)
KY: 0.000000 KX: 0.000000 RDX: 135.59298 AR: 0.449986 .times.
10.sup.-5 BR: 0.265979 .times. 10.sup.-7 CR: 0.143961 .times.
10.sup.-9 AP: 0.000000 .times. 10.sup.+0 BP: 0.000000 .times.
10.sup.+0 CP: 0.000000 .times. 10.sup.+0 r6 (First Reflecting
Surface) 521.799 Reflecting Surface (Anamorphic Aspherical Surface)
KY: 0.000000 KX: 0.000000 RDX: 1624.78 AR: -0.904617 .times.
10.sup.-6 BR: 0.545631 .times. 10.sup.-9 CR: 0.242759 .times.
10.sup.-11 AP: 0.000000 .times. 10.sup.+0 BP: 0.000000 .times.
10.sup.+0 CP: 0.000000 .times. 10.sup.+0 r7 (Incident Surface)
650.688 AIR r8 (Image Display Member) INFINITY BK7 r9 (Display
Surface) INFINITY Configuration of Each Surface Surface XSC YSC ZSC
ASC BSC CSC r1 0 0 0 0 0 0 r2 0 -4 14 2 0 0 r3 0 -3.5 14.52 -26 0 0
r4 0 -4 14 2 0 0 r5 0 1.6 17.2 2 0 0 r6 0 -4 14 2 0 0 r7 0 18.5
16.274 92 0 0 r8 0 21.296 18.260 70.558 0 0 r9 0 22.050 18.526
70.558 0 0
[0136]
5TABLE 5 Practical Example 5 Radius of Surface No. Curvature Medium
r1 (Pupil) INFINITY AIR r2 (Light-Beam-Selective Surface) -3634.791
PMMA (Anamorphic Aspherical Surface) KY: 0.000000 KX: 0.000000 RDX:
48284.671 AR: 0.306096 .times. 10.sup.-7 BR: 0.180844 .times.
10.sup.-10 CR: -0.845751 .times. 10.sup.-11 AP: -0.256283 .times.
10.sup.+1 BP: 0.365035 .times. 10.sup.+1 CP: 0.881357 .times.
10.sup.-1 r3 (Hologram Surface) INFINITY Reflecting Surface
Definitions of the two light beams HV1: REA HV2: VIR HX1: 0.000000
.times. 10.sup.-0 HY1: -0.930000 .times. 10.sup.+1 HZ1: -0.195000
.times. 10.sup.+2 HX2: 0.000000 .times. 10.sup.+0 HY2: 0.162516
.times. 10.sup.+6 HZ2: 0.100000 .times. 10.sup.+9 HWL: 532 Phase
Coefficient C2: 6.9110 .times. 10.sup.-1 C3: -8.9702 .times.
10.sup.-4 C5: 2.6889 .times. 10.sup.-3 C7: -5.0039 .times.
10.sup.-4 C9: 2.1491 .times. 10.sup.-3 C10: -7.6066 .times.
10.sup.-5 C12: 2.5558 .times. 10.sup.-4 C14: -4.0910 .times.
10.sup.-3 C16: 2.3755 .times. 10.sup.-5 C18: -3.8238 .times.
10.sup.-4 C20: 2.8438 .times. 10.sup.-3 C21: 5.0223 .times.
10.sup.-6 C23: -8.0868 .times. 10.sup.-6 C25: 2.2409 .times.
10.sup.-4 C27: -1.0917 .times. 10.sup.-3 C29: -1.9433 .times.
10.sup.-6 C31: 1.2785 .times. 10.sup.-5 C33: -7.4329 .times.
10.sup.-5 C35: 2.4587 .times. 10.sup.-4 C36: -1.3752 .times.
10.sup.-7 C38: -2.6743 .times. 10.sup.-7 C40: -5.6290 .times.
10.sup.-6 C42: 1.5020 .times. 10.sup.-5 C44: -3.2191 .times.
10.sup.-5 C46: 6.3467 .times. 10.sup.-8 C48: 1.6722 .times.
10.sup.-7 C50: 9.2383 .times. 10.sup.-7 C52: -1.7073 .times.
10.sup.-6 C54: 2.2440 .times. 10.sup.-6 C55: 7.7127 .times.
10.sup.-10 C57: -9.9455 .times. 10.sup.-9 C59: -1.2020 .times.
10.sup.-8 C61: -5.3627 .times. 10.sup.-8 C63: 8.2346 .times.
10.sup.-8 C65: -6.3220 .times. 10.sup.-8 r4 (Light-Beam-Selective
Surface) -3634.791 Reflecting Surface (Anamorphic Aspherical
Surface) KY: 0.000000 KX: 0.000000 RDX: 48284.671 AR: 0.306096
.times. 10.sup.-7 BR: 0.180844 .times. 10.sup.-10 CR: -0.845751
.times. 10.sup.-11 AP: -0.256283 .times. 10.sup.+1 BP: 0.365035
.times. 10.sup.+1 CP: 0.881357 .times. 10.sup.-1 r5 (Second
Reflecting Surface) -6093.456 Reflecting Surface (Anamorphic
Aspherical Surface) KY: 0.000000 KX: 0.000000 RDX: 1030.495 AR:
0.841364 .times. 10.sup.-6 BR: 0.427764 .times. 10.sup.-8 CR:
0.255300 .times. 10.sup.-10 AP: -0.745149 .times. 10.sup.-1 BP:
0.415246 .times. 10.sup.-1 CP: 0.691444 .times. 10.sup.-1 r6 (First
Reflecting Surface) 1337.490 Reflecting Surface (Anamorphic
Aspherical Surface) KY: 0.000000 KX: 0.000000 RDX: -162.844 AR:
0.564099 .times. 10.sup.-7 BR: -0.181479 .times. 10.sup.-8 CR:
0.199511 .times. 10.sup.-11 AP: 0.599536 .times. 10.sup.-1 BP:
-0.768584 .times. 10.sup.-0 CP: 0.141875 .times. 10.sup.+0 r7
(Incident Surface) 964.322 AIR (Anamorphic Aspherical Surface) KY:
0.000000 KX: 0.000000 RDX: -60.681 AR: -0.356007 .times. 10.sup.-7
BR: -0.552592 .times. 10.sup.-11 CR: 0.175467 .times. 10.sup.-14
AP: 0.146587 .times. 10.sup.+0 BP: 0.453286 .times. 10.sup.+0 CP:
0.596221 .times. 10.sup.-1 r8 (Image Display Member) INFINITY BK7
r9 (Display Surface) INFINITY Configuration of Each Surface Surface
XSC YSC ZSC ASC BSC CSC r1 0 0 0 0 0 0 r2 0 -4 14 2 0 0 r3 0 -3.5
14.52 -26 0 0 r4 0 -4 14 2 0 0 r5 0 1.6 17.2 2 0 0 r6 0 7.440
13.601 8 0 0 r7 0 8.339 -49.629 103.161 0 0 r8 0 25.985 13.447
81.911 0 0 r9 0 26.777 13.560 81.911 0 0
[0137]
6TABLE 6 Practical Example 6 Radius of Surface No. Curvature Medium
r1 (Pupil) INFINITY AIR r2 (Light-Beam-Selective Surface) INFINITY
PMMA r3 (Hologram Surface) INFINITY Reflecting Surface Definitions
of the two light beams HV1: REA HV2: VIR HX1: 0.000000 .times.
10.sup.+0 HY1: -0.930000 .times. 10.sup.+1 HZ1: -0.195000 .times.
10.sup.+2 HX2: 0.000000 .times. 10.sup.+0 HY2: 0.162516 .times.
10.sup.+6 HZ2: -0.100000 .times. 10.sup.+9 HWL: 532 Phase
Coefficient C2: 6.8410 .times. 10.sup.-1 C3: -1.1508 .times.
10.sup.-3 C5: 2.6937 .times. 10.sup.-3 C7: -5.6257 .times.
10.sup.-4 C9: 1.7114 .times. 10.sup.-3 C10: -9.2874 .times.
10.sup.-5 C12: 1.5613 .times. 10.sup.-4 C14: -4.5934 .times.
10.sup.-3 C16: 2.7208 .times. 10.sup.-5 C18: -2.2006 .times.
10.sup.-4 C20: 3.9194 .times. 10.sup.-3 C21: 6.5878 .times.
10.sup.-6 C23: -3.0441 .times. 10.sup.-6 C25: 1.4211 .times.
10.sup.-4 C27: -1.8275 .times. 10.sup.-3 C29: -1.7862 .times.
10.sup.-6 C31: 4.7416 .times. 10.sup.-6 C33: -5.0234 .times.
10.sup.-5 C35: 5.0373 .times. 10.sup.-4 C36: -1.9904 .times.
10.sup.-7 C38: -1.7706 .times. 10.sup.-7 C40: -2.5102 .times.
10.sup.-6 C42: 1.0445 .times. 10.sup.-5 C44: -8.1905 .times.
10.sup.-5 C46: 4.8792 .times. 10.sup.-8 C48: 1.4843 .times.
10.sup.-7 C50: 4.1718 .times. 10.sup.-7 C52: -1.1815 .times.
10.sup.-6 C54: 7.2665 .times. 10.sup.-6 C55: 1.9918 .times.
10.sup.-9 C57: -8.2678 .times. 10.sup.-9 C59: -1.1773 .times.
10.sup.-8 C61: -2.2918 .times. 10.sup.-8 C63: 5.5394 .times.
10.sup.-8 C65: -2.7140 .times. 10.sup.-7 r4 (Light-Beam-Selective
Surface) INFINITY Reflecting Surface r5 (Second Reflecting Surface)
INFINITY Reflecting Surface r6 (First Reflecting Surface) INFINITY
Reflecting Surface r7 (Incident Surface) INFINITY AIR r8
(Condenser) 25 BK7 r9 (Image Display Member) INFINITY BK7 r10
(Display Surface) INFINITY r11 (Condenser) 25 AIR r12 (Exiting
Surface) INFINITY PMMA r13 (Illuminant Reflecting Surface) -23
Reflecting Surface r14 (Illumination Light INFINITY AIR Incident
Surface) Configuration of Each Surface Surface XSC YSC ZSC ASC BSC
CSC r1 0 0 0 0 0 0 r2 0 -4 14 2 0 0 r3 0 -3.5 14.52 -26 0 0 r4 0 -4
14 2 0 0 r5 0 1.6 17.2 2 0 0 r6 0 -4 14 2 0 0 r7 0 19.331 37.594
87.098 0 0 r8 0 22.567 18.147 70.784 0 0 r10 0 23.984 18.641 70.784
0 0 r11 0 22.567 18.147 70.784 0 0 r12 0 19.331 37.594 87.098 0 0
r13 0 16 18 -60 0 0 r14 0 17 13.2 -15 0 0
[0138]
7TABLE 7 Practical Example 7 Radius of Surface No. Curvature Medium
r1 (Pupil) INFINITY AIR r2 (Light-Beam-Selective Surface) INFINITY
PMMA r3 (Reflecting Surface) -67.91807 PMMA Anamorphic Aspherical
Surface KY: -14.724953 KX: -20.432877 RDX: -47.45973 AR: -0.732699
.times. 10.sup.-5 BR: -0.163991 .times. 10.sup.-7 CR: 0.907725
.times. 10.sup.-10 AP: -0.281933 .times. 10.sup.+0 BP: -0.580876
.times. 10.sup.+0 CP: -0.477085 .times. 10.sup.+0 r4
(Light-Beam-Selective Surface) INFINITY PMMA r5 (Second Reflecting
Surface) INFINITY PMMA r6 (First Reflecting Surface) INFINITY PMMA
r7 (Incident Surface) 18.86098 PMMA Anamorphic Aspherical Surface
KY: 4.210342 KX: -1.870210 RDX: 20.49422 AR: 0.791098 .times.
10.sup.-5 BR: 0.825128 .times. 10.sup.-7 CR: 0.415047 .times.
10.sup.-7 AP: 0.774495 .times. 10.sup.+0 BP: -0.447736 .times.
10.sup.+0 CP: 0.512750 .times. 10.sup.-1 r8 (Display Surface)
INFINITY Configuration of Each Surface Surface XSC YSC ZSC ASC BSC
CSC r1 0 0 0 0 0 0 r2 0 -1.5 14 0 0 0 r3 0 2.773 12.370 33.850 0 0
r4 0 -1.5 14 0 0 0 r5 0 -1.5 17.5 0 0 0 r6 0 -1.5 14 0 0 0 r7 0
-22.677 17.183 -85.277 0 0 r8 0 -24.465 20.645 -29.042 0 0
[0139]
8TABLE 8 Practical Example 8 Radius of Surface No. Curvature Medium
r1 (Pupil INFINITY AIR r2 (Light-Beam-Selective Surface) INFINITY
PMMA r3 (Reflecting Surface) -65.81128 PMMA Anamorphic Aspherical
Surface KY: -18.964415 KX: -26.532434 RDX: -45.77309 AR: -0.416493
.times. 10.sup.-5 BR: -0.227125 .times. 10.sup.-7 CR: 0.714349
.times. 10.sup.-10 AP: -0.111311 .times. 10.sup.+0 BP: -0.508864
.times. 10.sup.+0 CP: -0.483015 .times. 10.sup.+0 r4
(Light-Beam-Selective Surface) INFINITY PMMA r5 (Second Reflecting
Surface) INFINITY PMMA r6 (First Reflecting Surface) INFINITY PMMA
r7 (Incident Surface) 682.37441 PMMA Anamorphic Aspherical Surface
KY: -0.051939 KX: 356.459186 RDX: -107.42767 AR: 0.251651 .times.
10.sup.-4 BR: -0.239984 .times. 10.sup.-6 CR: 0.107859 .times.
10.sup.-7 AP: 0.144849 .times. 10.sup.+1 BP: 0.119571 .times.
10.sup.+0 CP: 0.110662 .times. 10.sup.+0 r8 (Display Surface)
INFINITY Configuration of Each Surface Surface XSC YSC ZSC ASC BSC
CSC r1 0 0 0 0 0 0 r2 0 -1.5 14 0 0 0 r3 0 6.695 9.614 37.425 0 0
r4 0 -1.5 14 0 0 0 r5 0 -6.2 17.5 3 0 0 r6 0 -1.5 14 0 0 0 r7 0
-26.746 22.320 -96.260 0 0 r8 0 -28.092 19.877 -38.862 0 0
[0140]
9TABLE 9 Practical Example 9 Radius of Surface No. Curvature Medium
r1 (Pupil) INFINITY AIR r2 (Light-Beam-Selective Surface) -400 PMMA
r3 (Reflecting Surface) -53.50019 PMMA Anamorphic Aspherical
Surface KY: -11.608841 KX: -18.114889 RDX: -44.01804 AR: -0.941850
.times. 10.sup.-5 BR: -0.197815 .times. 10.sup.-7 CR: 0.150623
.times. 10.sup.-9 AP: -0.151288 .times. 10.sup.+0 BP: -0.106976
.times. 10.sup.+1 CP: -0.924051 .times. 10.sup.+0 r4
(Light-Beam-Selective Surface) -400 PMMA r5 (Second Reflecting
Surface) -477.32126 PMMA Rotationally Symmetrical Aspherical
Surface K: 0.000000 A: 0.793161 .times. 10.sup.-7 B: 0.28269
.times. 10.sup.-8 C: 0.227445 .times. 10.sup.-11 r6 (First
Reflecting Surface) -400 PMMA r7 (Incident Surface) 8.78367 PMMA
Anamorphic Aspherical Surface KY: -5.765127 KX: 0.620164 RDX:
20.95733 AR: 0.133517 .times. 10.sup.-4 BR: -0.126397 .times.
10.sup.-6 CR: 0.829424 .times. 10.sup.-7 AP: 0.269913 .times.
10.sup.+0 BP: -0.310065 .times. 10.sup.+1 CP: 0.125716 .times.
10.sup.+0 r8 (Display Surface) INFINITY Configuration of Each
Surface Surface XSC YSC ZSC ASC BSC CSC r1 0 0 0 0 0 0 r2 0 0.1 14
0 0 0 r3 0 3.695 11.7 35.728 0 0 r4 0 0.1 14 0 0 0 r5 0 0.1 17.5 0
0 0 r6 0 0.1 14 0 0 0 r7 0 -24.296 19.499 -98.937 0 0 r8 0 -25.225
20.034 -37.526 0 0
[0141]
10TABLE 10 Practical Example 10 Radius of Surface No. Curvature
Medium r1 (Pupil) INFINITY AIR r2 (Light-Beam-Selective Surface)
INFINITY PMMA r3 (Reflecting Surface) INFINITY PMMA Hologram
Definitions of the two light beams HV1: REA HV2: VIR HX1: 0.000000
.times. 10.sup.+0 HY1: -0.930000 .times. 10.sup.+1 HZ1: -0.195000
.times. 10.sup.+2 HX2: 0.000000 .times. 10.sup.+0 HY2: 0.435556
.times. 10.sup.-6 HZ2: -0.276247 .times. 10.sup.+7 HWL: 532 Phase
Coefficient C2: -2.7403 .times. 10.sup.-1 C3: -5.5899 .times.
10.sup.-4 C5: 3.5457 .times. 10.sup.-3 C7: 1.1443 .times. 10.sup.-4
C9: 1.2053 .times. 10.sup.-4 C10: 2.1687 .times. 10.sup.-5 C12:
-1.5075 .times. 10.sup.-4 C14: -5.4541 .times. 10.sup.-4 C16:
1.1868 .times. 10.sup.-5 C18: -3.7214 .times. 10.sup.-5 C20:
-2.5027 .times. 10.sup.-4 C21: -9.9841 .times. 10.sup.-7 C23:
5.8089 .times. 10.sup.-6 C25: 6.6827 .times. 10.sup.-6 C27: -4.6473
.times. 10.sup.-5 C29: -1.8211 .times. 10.sup.-7 C31: 2.6129
.times. 10.sup.-6 C33: 7.1404 .times. 10.sup.-6 C35: -1.0668
.times. 10.sup.-6 C36: 1.7421 .times. 10.sup.-8 C38: 1.4214 .times.
10.sup.-8 C40: 6.8433 .times. 10.sup.-7 C42: 1.7906 .times.
10.sup.-6 C44: 8.8158 .times. 10.sup.-7 C46: 3.7198 .times.
10.sup.-9 C48: 1.0953 .times. 10.sup.-8 C50: 8.3581 .times.
10.sup.-8 C52: 1.9290 .times. 10.sup.-7 C54: 1.2291 .times.
10.sup.-7 C55: -7.0148 .times. 10.sup.-11 C57: 4.0400 .times.
10.sup.-10 C59: 9.0113 .times. 10.sup.-10 C61: 3.7530 .times.
10.sup.-9 C63: 7.7647 .times. 10.sup.-9 C65: 5.1387 .times.
10.sup.-9 r4 (Light-Beam-Selective Surface) INFINITY PMMA r5
(Second Reflecting Surface) INFINITY PMMA r6 (First Reflecting
Surface) INFINITY PMMA r7 (Incident Surface) INFINITY PMMA r8
(Display Surface) INFINITY Configuration of Each Surface Surface
XSC YSC ZSC ASC BSC CSC r1 0 0 0 0 0 0 r2 0 -1.5 16 0 2 0 r3 0
0.0467 16.4 30 0 0 r4 0 -1.5 16 0 0 0 r5 0 -1.5 19.8 0 0 0 r6 0
-1.5 16 0 0 0 r7 0 -21.316 36.342 -83.546 0 0 r8 0 -26.338 24.785
-57.550 0 0
[0142]
11TABLE 11 Practical Example 11 Surface No. Radius of Curvature
Medium r1 (Pupil) INFINITY AIR r2 (Light-Beam- INFINITY PMMA
Selective Surface) r3 (Reflecting Surface) INFINITY PMMA Hologram
Definitions of the two light beams HV1:REA HV2:VIR HX1:0.000000
.times. 10.sup.+0 HY1:-0.930000 .times. 10.sup.+1 HZ1:-0.195000
.times. 10.sup.+2 HX2:0.000000 .times. 10.sup.+0 HY2:0.435556
.times. 10.sup.+6 HZ2:-0.276247 .times. 10.sup.+7 HWL:532 Phase
Coefficient C2:-2.5943 .times. 10.sup.-1 C3:-3.2624 .times.
10.sup.-4 C5:1.6372 .times. 10.sup.-3 C7:3.0074 .times. 10.sup.-4
C9:-4.5208 .times. 10.sup.-5 C10:-1.4408 .times. 10.sup.-5
C12:4.5938 .times. 10.sup.-5 C14:-5.9452 .times. 10.sup.-4
C16:-1.6161 .times. 10.sup.-6 C18:8.0915 .times. 10.sup.-5
C20:-2.5984 .times. 10.sup.-4 C21:5.0639 .times. 10.sup.-7
C23:-1.1377 .times. 10.sup.-6 C25:3.4244 .times. 10.sup.-5
C27:-4.9979 .times. 10.sup.-5 C29:2.1833 .times. 10.sup.-7
C31:-1.8584 .times. 10.sup.-6 C33:8.3435 .times. 10.sup.-6
C35:-1.8062 .times. 10.sup.-6 C36:-1.1090 .times. 10.sup.-8
C38:-4.0064 .times. 10.sup.-8 C40:-5.6494 .times. 10.sup.-7
C42:1.3278 .times. 10.sup.-6 C44:9.1143 .times. 10.sup.-7
C46:-5.3456 .times. 10.sup.-9 C48:-1.2695 .times. 10.sup.-8
C50:-6.3208 .times. 10.sup.-8 C52:1.2463 .times. 10.sup.-7
C54:1.4644 .times. 10.sup.-7 C55:5.5275 .times. 10.sup.-11
C57:-5.9780 .times. 10.sup.-10 C59:-6.1101 .times. 10.sup.-10
C61:-2.4014 .times. 10.sup.-9 C63:5.0146 .times. 10.sup.-9
C65:6.8781 .times. 10.sup.-9 r4 (Light-Beam- INFINITY PMMA
Selective Surface) r5 (Second Reflecting INFINITY PMMA Surface) r6
(First Reflecting INFINITY PMMA Surface) r7 (Incident Surface)
INFINITY PMMA r8 (Display Surface) INFINITY Configuration of Each
Surface Surface XSC YSC ZSC ASC BSC CSC r1 0 0 0 0 0 0 r2 0 -1.5 16
0 0 0 r3 0 -0.455 16.33 30 0 0 r4 0 -1.5 16 0 0 0 r5 0 -6.8 19.8 4
0 0 r6 0 -1.5 16 0 0 0 r7 0 -22.917 49.152 -81.318 0 0 r8 0 -29.225
21.517 -56.721 0 0
* * * * *