JPH0779393A - Visual sense display device - Google Patents

Abstract

PURPOSE:To enable a user to view a video image with wide field angle and high resolution by a visual sense display device such as a head mount display device. CONSTITUTION:Two 2-dimension display elements 4, 5 whose display screens are opposite to each other, two half mirrors 6, 7 in pairs with the display elements 4, 5 and combined in a V-shape, and a concaved mirror 8 having the same axis as the center axis of the two half mirrors 6, 7 combined to be a V-shape are arranged and images 11, 10 having a wider area than a half including an overlap area 9 are displayed on the two 2-dimension display elements 4, 5 and the two half mirrors 6,7 combined to V-shape synthesize the images into one consecutive video image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a visual display device,
In particular, it relates to a visual display device such as a head-mounted display device capable of observing an image with a wide angle of view and high resolution.

[0002]

2. Description of the Related Art For virtual reality, or
Development of a helmet-type or goggle-type head-mounted display device is in progress for the purpose of enabling one person to enjoy a large-screen image.

By the way, conventionally, as an observer's head-mounted display device, as shown in FIG. 24, a display image of a two-dimensional display element 1 such as a liquid crystal display device is displayed on the front surface of a user's eyeball.
It is reflected by the half mirror 2 that is inclined at an angle, and is enlarged by the concave mirror 3 that is arranged further in front of the half mirror 2.
It is known that the enlarged display image can be observed again through the half mirror 2 (Japanese Patent Laid-Open No. 3-1.
88777). The two-dimensional display element 1 is arranged near the front focus position of the concave mirror 3.

Here, the distance (working distance) between the above optical system and the eyeball of the user is WD, the diameter of the concave mirror 3 is D,
When the thickness of the optical system is set to t and the passage area of the chief ray is considered, the following formula is established from FIG. Since D and t are substantially equal to the vertical and horizontal widths of the half mirror 2 tilted at 45 °, respectively, as a result, D and t have substantially the same value.

D = 2 (t + WD) tan (θ / 2) t = D t {1-2tan (θ / 2)} = 2WDtan (θ / 2) ∴t = 2WDtan (θ / 2) / {1-2tan (Θ / 2)}.

[0006]

Considering the usability of such a head-mounted display device, it is necessary to secure WD of 10 mm or more and 25 mm or less.
In the case of mm and the angle of view θ = 40 °, it can be seen from the above equation that the thickness t of the optical system becomes very large at t = 53 mm. Moreover, in actuality, in addition to the chief ray, it is necessary to secure a passage area for the dependent rays, and a larger optical system is required.

Further, since a small two-dimensional display element does not have a sufficient number of pixels, there is a problem that an image observed by enlarging the two-dimensional display element does not have sufficient resolution. Therefore, the inventor considered that a plurality of such display elements are arranged in parallel to obtain a wide screen. However, a light-weight liquid crystal display device is generally used for a head-mounted display device such as a head-mounted display device. As shown in the figure, since the display screen is surrounded by the substrate portion K around the screen G, even if these are arranged side by side, the substrate portions B interfere with each other, which is inconvenient.

The present invention has been made in view of the above problems of the prior art, and an object thereof is to provide a visual display device such as a head-mounted display device with a wide angle of view and high resolution. Is to be able to observe.

[0009]

A visual display device of the present invention which achieves the above object, comprises a two-dimensional display means and an eyepiece optical system for projecting an image formed by the two-dimensional display means and guiding it to an observer's eyeball. And a first image display unit for displaying at least a part of an image guided to an observer's eye, in the visual display device.
Second video display means for displaying the video display portion including another portion different from the video display portion, and
The eyepiece optical system includes a first reflecting surface that reflects the first image formed by the first image display unit, and a second reflecting surface that reflects the second image formed by the second image display unit.
Of the first image and the second image, and an optical system having a positive power for projecting the combined image of the first image and the second image into the observer's eyeball by magnifying and projecting the combined image with respect to the first reflecting surface. The second
The reflective surface of is arranged at an angle.

In this case, it is desirable to dispose both the first reflecting surface and the second reflecting surface between the first image display means and the second image display means. Further, the optical system having positive power can be composed of a concave mirror. It is desirable that the optical system having positive power includes a wave plate having a curved shape.

Further, an optical system having at least one of the first reflecting surface and the second reflecting surface or an external optical path passing therethrough and having a positive power is provided by the first image display means and the second image display. Two units are provided corresponding to the means, and a first image display unit and a second image display unit are provided across the external optical path, and
It is also possible to arrange two optical systems having a positive power. In that case, it is desirable that the combined power of the optical system provided on the external optical path is substantially zero.

[0012]

The basic structure and operation of the visual display device of the present invention will be described below with reference to FIGS. As shown in FIG. 1A, a visual display device according to the present invention comprises two two-dimensional display elements 4 and 5 whose display surfaces face each other, and a pair of these display elements 4 and 5, and , Two half mirrors 6 and 7 combined in a "V" shape, and two half mirrors 6 combined in a "V" shape,
A concave mirror 8 having the same axis as the central axis of 7 is arranged. In the case of FIG. 1A, the half mirrors 6 and 7 are
Although they are arranged nearer to the display elements 4 and 5, respectively,
As shown in FIG. 2A, they may be arranged nearer to the display elements 5 and 4, respectively. Also, instead of the concave mirror 8, FIG.
As shown in (a), a convex lens 8'may be used.

In such a structure, the two two-dimensional display elements 4 and 5 have the final display device as shown in FIGS. 1 (d), 2 (d) and 3 (d), respectively. Images 11 and 10 (Figs. 1 (b) and (c)) or 11 'of a region wider than half including the overlapping region 9 of the projected image "R",
10 '(FIG. 2 (c), (b)) or 11 ″, 10 ″ (FIG. 3 (b), (c)) is displayed. These display images are
Just as the image of the two-dimensional display element 4 is reflected by the half mirror 6 and the image of 5 is reflected by 7, the two half mirrors 6 and 7 combined in the “V” shape are respectively reflected to form one connection. It is combined with the video. Then, this image is further reflected by the concave mirror 8 or refracted by the convex lens 8'and becomes an enlarged aerial image. Then, the user can observe this enlarged image.

In particular, when the magnified image is formed by the concave mirror 8 shown in FIGS. 1 and 2, since there is little aberration, it is possible to obtain a clear image with a large angle of view, which is suitable for a large angle of view. There is. Then, as the angle of view becomes larger, the thickness of the entire optical system becomes significantly smaller than that of the conventional optical system. Hereinafter, the thickness t of the optical system of FIG. 1 will be roughly estimated from the principal ray passing region. As is clear from FIGS. 1 and 2, D = t in the conventional optical system shown in FIG.
In this optical system, D = 2t.

D = 2 (t + WD) tan (θ / 2) 2t {1-tan (θ / 2)} = 2WDtan (θ / 2) ∴t = WDtan (θ / 2) / {1-tan (θ / 2)} Therefore, the working distance WD is 20 mm and the angle of view θ is 40 °.
In the case of, the thickness t of the optical system is 11.5 m from the above formula.
m. Actually, it is necessary to have a larger thickness because it is necessary to secure a transmission area for dependent rays, but the thickness of the conventional optical system calculated under the same conditions is 53 mm,
Compared to this, it is about 1/5 thinner, and it is certain that there will be a great improvement in thickness.

The two-dimensional display elements 4 and 5 are the concave mirror 8
Is arranged near the front focus position of the user's eye, and the pupil of the user's eye is arranged near the rear focus position. Therefore, when the optical path is traced with the concave mirror 8 as a reference, the distance to the two-dimensional display elements 4, 5 is increased. And the distance to the eye almost match. Therefore, it is easily understood from FIGS. 1 and 2 that the optical paths s and t and the optical paths s ′ and t ′ have the same length, respectively, and if WD is the same, s ′ becomes shorter than s. I understand. That is, as shown in FIG. 2, in the type in which the ridge lines of the half mirrors 6 and 7 combined in the shape of "V" are located on the side opposite to the concave mirror 8, the height direction of the optical system can be downsized.

Further, since one image is produced by using the two two-dimensional display elements 4 and 5, the number of effective pixels is about twice the number of pixels of one sheet, and high resolution is achieved. In particular, when the pixels of the two-dimensional display elements 4 and 5 are arranged such that the pixels are displaced from each other by a half pitch when the images are combined by the half mirrors 6 and 7, the overlap area 9 has a higher resolution effect. can get.

Further, in the present invention, as shown in the following embodiments, instead of using the half mirrors combined in the shape of "V", when the two half mirrors are viewed from the side, the shape of "X" is formed. It can also be configured in parallel so as to be.

[0019]

EXAMPLES Some examples of the visual display device of the present invention will be described below. First Embodiment FIGS. 4A to 4C show the main part of this embodiment. 1 in the figure
Reference numerals 2 and 13 are two-dimensional display elements, 14 and 15 are half mirrors assembled at right angles to each other, and 16 is a concave mirror. FIG. 4D shows an image (observed image) observed on the display device of this example. The half mirrors 14 and 1
As will be described later, No. 5 is manufactured by using a louver type filter as a substrate and applying a half mirror coat on the surface thereof.

In this embodiment, a video signal processing device (not shown) serves to send an image sent from the outside to the upper and lower halves (or the left and right halves) and the overlap region (the same as region 9 in FIG. 1). The image signal is separated into an image of an area larger than the two equal parts including the area, and the image signal is sent to the two-dimensional display elements 12 and 13. Two-dimensional display elements 12, 13
Areas A and A'on the display surface are areas for displaying the upper half (or the right half) and the lower half (or the left half) of the image respectively sent, and the areas B and B'are the same. Near the upper end of the lower half (or left half) of the sent image (or
It is an area for displaying the vicinity of the right end) and the vicinity of the lower end of the upper half (or the right half) (or the vicinity of the left end). That is, the two-dimensional display elements 12 and 13 are composed of areas A and B and areas A ′ and B ′, respectively, and display a partially common image slightly larger than the upper and lower half (or the left and right half) of the observed image. .
Then, in a portion of the two-dimensional display elements 12 and 13 that displays a common image, a pair of images are displayed on opposite sides of 180 ° with the ridge line L between the half mirrors 14 and 15 being sandwiched. Therefore, when the image of the two-dimensional display element 12 is reflected by the half mirror 14 and the image of the two-dimensional display element 13 is reflected by the half mirror 15, the divided image is optically 1
Are combined into one continuous image. Then, this image is reflected by the concave mirror 16 to form a magnified image in the air.

Hereinafter, a detailed description will be given of how a light beam emitted from each point of the two-dimensional display elements 12 and 13 forms an aerial image, with a few points on the two-dimensional display elements 12 and 13 as representatives.
First, how the image of the peripheral portion of the observation image is formed will be described by taking the image formation of the observation image P1 (FIG. 4D) as an example. In FIG. 4A, the principal ray of the luminous flux emitted by p1 on the display surface of the two-dimensional display element 12 is the two-dimensional display element 12
This light flux is first reflected by the half mirror 14 and travels toward the concave mirror 16 side. The concave mirror 16 has its front focus position in the vicinity of the display surfaces of the two-dimensional display elements 12 and 13, and therefore the light flux is reflected by this concave mirror 16,
It becomes a substantially parallel light flux. Then, it again passes through the half mirror 14 and forms an exit pupil at the rear focal position of the concave mirror 16.
When the user's pupil is arranged according to this position and the device is looked into, the aerial image P1 of p1 displayed by the two-dimensional display element 12 is displayed.
(FIG. 4 (d)) can be observed. In this way, the periphery of the observation image is formed only from the image displayed by either the two-dimensional display element 12 or 13.

Next, an image P2 near the center of the observed image (see FIG.
How (d)) is formed will be described. Figure 4
In (b), this image P2 is an image in which the display point p2 of the two-dimensional display element 12 and the display point p2 'of the two-dimensional display element 13 are combined and projected. As described above, p2 and p2 ′ are 180 ° about the ridge line L of the half mirrors 14 and 15 as an axis.
The same image is displayed at two points located on the opposite side. Due to the mutual positional relationship, the reflection images on the half mirrors 14 and 15 are formed at the same position. And p2, p2 '
With respect to the luminous flux emitted from any of the points, since the half mirrors 14 or 15 are not large enough, not all the luminous flux is reflected and only a part of the luminous flux goes to the concave mirror 16. However, p2, p
As can be seen from the figure, the entire luminous flux emitted from both 2'points is a luminous flux having the same predetermined thickness as the luminous flux reflected by the half mirror 14 of p1. Then, similarly to the light flux of p1, it is reflected by the concave mirror 16 to become a substantially parallel light flux, forms an enlarged image in the air, and forms an exit pupil that satisfies a predetermined pupil diameter at the exit pupil position.

Image P3 at the center of the observed image (FIG. 4 (d))
Image formation will be described. In FIG. 4A, this image P3
The display points on the two-dimensional display elements 12 and 13 that form
3, p3 '. In particular, these two points are not only located on the opposite side of 180 ° with respect to the ridgeline L of the half mirrors 14 and 15 like p2 and p2 ′, but the straight line connecting these two points p3 and p3 ′ is the optical axis of the concave mirror 16. It is in a position orthogonal to. That is, it is on the boundary between the areas A and B or A ′ and B ′.
Then, the light beams emitted from these two points are combined by the half mirrors 14 and 15 into a single normal light beam diameter as with p2 and p2 ′, and are reflected by the concave mirror 16 to form an image P3 (FIG. 4).
(D)) is formed.

Next, referring to FIG. 4C, the points p4 and p4 'on the two-dimensional display elements 12 and 13 will be described.
The point p4 is a point at the boundary position where the light beam emitted from the half mirror 14 is entirely reflected by the half mirror 14 as in the case of the point p1 or a part thereof cannot be reflected like the point p2. Then, at least with respect to the display point sandwiched between the points p4 and p3, it is necessary to secure the corresponding point on the side of the two-dimensional display element 13 as is the case with the corresponding point p2 'on p2. The corresponding point of p4 is p4 '. Also, this is
Two-dimensional display element 12 for a point on the two-dimensional display element 13
The same applies to the corresponding points above.

When the lights emitted from the two-dimensional display elements 12 and 13 pass through the half mirrors 14 and 15 and are reflected again by the half mirrors 15 and 14, these lights are directed to the eyes of the user. It causes flare. Therefore, it is necessary to block this light somewhere. Therefore,
The half mirror coat 19 is applied to the surface of the louver type filter substrate to form the half mirrors 14 and 15.
FIG. 5 is a partial sectional view of the half mirrors 14 and 15, respectively.
Shown in (a) and (b). The louver filter is a filter in which light-transmitting holes 17 and light-shielding walls 18 are alternately formed as shown in the figure, and has a function of passing light in a specific direction and blocking light in a specific direction. The half mirrors 14 and 15 using this filter as a substrate are the two-dimensional display element 1.
The light from 2 and 13 is the half mirror coat part 1 on the surface.
Even when the light passes through 9, the light is blocked by the louver type filter unit, so that the light causing flare does not occur. Further, the light reflected from the concave mirror 16 can pass through the louver type filter portion after passing through the half mirror coat portion 19. The pitch of the light shielding wall 18 is 0.2 mm
The above is good. If it is smaller than this, the observation image is disturbed by the diffraction effect of light.

Second Embodiment A second embodiment will be described with reference to FIG. This embodiment is the same as the first embodiment except for a part. Therefore, only different parts will be described. In the figure, 20 is a polarizer,
Reference numeral 21 is a λ / 4 plate, and 22 is an analyzer. Further, the half mirrors 14 and 15 do not use a louver type filter as a substrate, but are ordinary glass plates to which a half mirror coat is applied. The light beam emitted from the two-dimensional display element 12 passes through the polarizer 20 to become linearly polarized light, which is reflected by the half mirror 14. However, some light passes through the half mirror and is reflected by the half mirror 15,
Head to the user's eyes. If this light reaches the eye, it creates flare and becomes a problem. However, since the analyzer 22 whose polarization direction is orthogonal to this light is arranged in front of the eyeball, it is shielded here and does not reach the eyeball.

On the other hand, the light reflected by the half mirror 14 is
After passing through the λ / 4 plate 21, it is reflected by the concave mirror 16 and again λ /
4 Pass through the plate 21. By passing through the λ / 4 plate 21 twice, the polarization direction is rotated by 90 °.
It becomes polarized light parallel to 2 and passes through the analyzer 22 to reach the eyeball. The same applies to light emitted from the two-dimensional display element 13. This allows the user to observe a clear image without flare.

Third Embodiment A third embodiment will be described with reference to FIG. This embodiment is the same as the first embodiment except for a part. Therefore, only different parts will be described. In the figure, 23 is a crystal wave plate having a thickness of 1 mm or more. Also, half mirrors 14 and 15
The above substrate is not a louver type filter but a linear polarizing plate orthogonal to each other, the front surface of which is provided with a half mirror coat and the back surface thereof is provided with an antireflection coat.

The light rays emitted from the two-dimensional display element 12 are
Reflects the half mirror 14. However, a part of the light passes through the half mirror 14, but at this time, since the half mirror substrate is a linear polarization plate, this transmitted light becomes a linear polarization. Then, the light enters the half mirror 15, but since the back surface of the half mirror 15 is coated with an antireflection coating, the light does not reflect there and go to the eyes of the user, but enters the substrate. However, since this substrate is a linear polarization plate whose polarization direction is orthogonal to that of the incident light, all the incident light is absorbed. Therefore, flare-causing light is not generated. Further, the light directed to the concave mirror 16 passes through the wave plate 23 twice in a reciprocating manner. At this time, a slight change in the wavelength causes a large change in the polarization state, and the light is substantially depolarized. As a result, the reflected light is reflected by the half mirrors 14 and 15
Since it can pass through any of the substrates, the user can observe a clear image.

Fourth Embodiment A fourth embodiment will be described with reference to FIG. This embodiment is the same as the first embodiment except for a part. Therefore, only different parts will be described. In the figure, 24 is a convex lens. As shown in the figure, the inclination angle of the principal ray reflected by the concave mirror 16 is refracted by the convex lens 24 and becomes larger. That is, even in the optical system of the first embodiment, compared with the conventional optical system,
A large angle of view can be obtained without increasing the thickness, but in the present embodiment, the angle of view is further increased by disposing the convex lens 24 between the half mirrors 14 and 15 and the eyeball. Further, the function of the convex lens 24 brings the front focus position of the entire optical system closer to the concave mirror 16, so that the positions of the two-dimensional display elements 12 and 13 can be brought closer to the half mirrors 14 and 15 side, and the height of the optical system is increased. It also has the effect of reducing the size. Further, the Petzval sum of the concave mirror 16 and the Petzval sum of the convex lens 24 have opposite signs, and have the effect of canceling each other. Therefore, it also has an effect of improving the field curvature of the entire optical system.

Fifth Embodiment A fifth embodiment will be described with reference to FIG. This embodiment is the same as the fourth embodiment except for a part. Therefore, only different parts will be described. In the figure, 25 is as shown
It is an aspherical concave lens with large decentering. In the fourth example, the working distance is shortened by the convex lens 24, but in the present example, the working distance is near the two-dimensional display elements 12 and 13 near the front focus of the optical system shown in the fourth example. By arranging the concave lens 25, the rear focal position is moved rearward from the optical system without changing the focal length of the entire system. As a result, the working distance can be increased without significantly reducing the angle of view. The optical axis (rotational axis) of the concave lens 25 coincides with the principal rays of p3 and p3 ′ (FIG. 4A). The aspherical concave lens 25 has a function of correcting the pincushion-type image distortion caused by the concave mirror 16 by its aspherical surface action, and the aspherical surface has a shape in which the curvature gradually increases as the distance from the optical axis increases. ing.

Sixth Embodiment A sixth embodiment will be described with reference to FIG. This embodiment is the same as the second embodiment except for a part. Therefore,
Only different parts will be described. In the figure, 26 is a triangular prism, 27 is a V-shaped prism, and 28 is a concave mirror in which the back surface of a convex lens is mirror-coated. The triangular prism 26 and the V-shaped prism 27 are joined together to form one prism as a whole. A half mirror coat is applied to the joint surface, and the half mirror 1 shown in the second embodiment is used.
It has the same function as 4 and 15. In addition, the concave mirror 28 also has a second
Similar to the concave mirror 16 of the embodiment, the two-dimensional display elements 12, 13 are
However, the concave mirror in which the back surface of the convex lens is mirror-coated in this manner causes less field curvature than the concave mirror 16 shown in the second embodiment, and a good image can be obtained. To be

As shown in the figure, most of the optical path between the concave mirror 28 and the user's eye is filled with prisms, but this has the function of moving away both the front focus position and the rear focus position of the concave mirror 28. The focal length of the concave mirror 28 can be shortened accordingly. Therefore, a large enlargement ratio of the two-dimensional display elements 12 and 13 can be obtained, and a large angle of view can be obtained.

Seventh Embodiment A seventh embodiment will be described with reference to FIG. This embodiment is the same as the sixth embodiment except for a part. Therefore,
Only different parts will be described. In the figure, 29 is a triangular prism and 30 is a V-shaped prism. Triangular prism 29 and V
The C-shaped prisms 30 are bonded to each other, and a polarization half mirror coat is applied to the bonding surface. For this reason,
P-polarized light is efficiently transmitted therethrough, and S-polarized light is efficiently reflected. The two-dimensional display elements 12 and 13 are TFT type LCDs (liquid crystal display devices), and are illuminated from the back side by a backlight (not shown) to emit S-polarized light. This light is efficiently reflected by the above-mentioned polarized half mirror coat portion, reflected by the concave mirror 28, and enters the polarized half mirror coat again. During this time, the light passes through the λ / 4 plate 21 twice, so that the light P
It has changed to polarized light and efficiently passes through this polarized half mirror. Therefore, a brighter image can be observed. The incident surface of the V-shaped prism 30 is a eccentric concave surface, which functions as the eccentric concave lens 25 shown in the fifth embodiment, and the exit surface of the triangular prism 29 is a convex surface. The function of the convex lens 24 shown in the fifth embodiment is provided.

Eighth Embodiment An eighth embodiment will be described with reference to FIG. This embodiment is the same as the seventh embodiment except for a part. Therefore,
Only different parts will be described. In the figure, reference numeral 31 is a concave mirror in which a concave lens and a convex lens are cemented and the convex surface is mirror-coated. The prisms 29 and 30 are made of plastic or glass, and these materials have chromatic dispersion. Therefore, the optical path length for short light becomes shorter than that for light having a long wavelength. Then, this causes chromatic aberration. Also,
In addition, chromatic aberration occurs on the convex surface of the exit surface of the triangular prism 29. In order to correct this, the seventh embodiment
Instead of the convex lens 28 of the embodiment, a cemented concave mirror 31 of a concave lens and a convex lens having mutually different dispersion characteristics is used,
Corrects chromatic aberration.

Ninth Embodiment A ninth embodiment will be described with reference to FIG. This embodiment is the same as the first embodiment except for a part. Therefore,
Only different parts will be described. In the figure, 32 and 33 are half mirrors using general optical glass for the substrate. The half mirrors 32 and 33 are combined in a “V” shape at an angle of 110 ° (α) with each other. In the first embodiment,
Corresponding points (eg, p2 and p2 ′, p3 and p3 ′, p4 and p4 ′) of the two-dimensional display elements 12 and 13 are located on opposite sides of 180 ° with respect to the ridge line L of the half mirrors 12 and 13. However, in the present embodiment, the corresponding points are located at 140 ° (β = 360 ° -2α) across the ridge line L. As a result, the images divided and displayed on the two two-dimensional display elements 12 and 13 are reflected by the half mirrors 32 and 33 to be combined into one image.

In the first embodiment, a louver type filter is used as the substrate of the half mirrors 14 and 15 in order to remove the light that causes flare. However, in this embodiment, since the general optical glass is used, part of the light emitted from the two-dimensional display elements 12 and 13 is partially reflected by the half mirrors 32 and 3.
Pass 3 as it is. However, as mentioned above,
The half mirrors 32 and 33 are not right angles but obtuse angles (α = 11
(0 °), the light that passes through the half mirror 32 or 33 and is reflected by the next half mirror 33 or 32 is also out of the user's pupil along the optical path indicated by the dotted line in the figure. Does not cause

Tenth Embodiment A tenth embodiment will be described with reference to FIG. 14 which is similar to FIG. This embodiment is the same as the second embodiment except for a part. Therefore, only different parts will be described. In the second embodiment, the ridge lines L of the half mirrors 14 and 15 face the concave mirror 16 side, but in the present embodiment, they face the opposite side, as shown in FIG. And the two-dimensional display element 1
Half mirrors paired with 2, 13 are 15, 14 respectively.
Is. That is, the light emitted from the two-dimensional display element 12 (13) passes through the half mirror 14 (15) and is reflected by the half mirror 15 (14) to form one combined image. The images displayed on the two-dimensional display elements 12 and 13 are also displayed in the second
In the embodiment, the image displayed on the two-dimensional display elements 13 and 12 is displayed. For example, in order to form the composite image of FIG.
((B) in the figure) and 11 '((c) in the figure) are displayed. In this embodiment, since the positions of the two-dimensional display elements 12 and 13 are close to the half mirrors 14 and 15 even if the working distance is made longer than in the second embodiment, the height of the entire optical system can be made compact. .

If the concave mirror 16 in the first embodiment is a half mirror-coated concave mirror, the two-dimensional display element 12,
It is also possible to superimpose an external image on 13 and observe, and even when a convex lens is arranged immediately in front of the user's eye as in the fourth embodiment, the concave mirror 16 is used as a half mirror coat. Further, by disposing a concave lens having an appropriate refractive power on the outside world side, it becomes possible to observe the outside world image in superposition.

Eleventh Embodiment An eleventh embodiment will be described with reference to FIG. In the figure, 38 and 39 are total reflection mirrors instead of half mirrors,
40 is a convex lens. In this embodiment as well, as in the previous embodiments, the images of the two-dimensional display elements 12 and 13 are combined into one image by the mirrors 38 and 39 that are combined in the shape of the letter "V", and the combined image is placed in the air by the convex lens 40. It is magnified and projected. Therefore, the display surfaces of the two-dimensional display elements 12 and 13 are arranged near the front focus position of the convex lens 40. In this optical system, the "V" -shaped optical system is not a half mirror but a total reflection mirror, so that light utilization efficiency is good and a brighter image can be observed.

Twelfth Embodiment Next, an embodiment in which two half mirrors are arranged in parallel so as to form an “X” shape when viewed from the side, instead of the half mirrors combined in the “V” shape. Will be described with reference to the perspective view of FIG. In the figure, reference numerals 12 and 13 denote two-dimensional display elements, and their display surfaces are arranged so as to face each other with a display screen offset and substantially parallel to the visual axis of the user. Left and right beam splitter prisms intersecting the visual axis are arranged side by side, and 44 and 45 are respective half mirrors, and their reflecting surfaces form an angle of approximately 90 ° with each other and with respect to the visual axis. They form an angle of about 45 ° and are arranged so as to form an “X” shape when viewed from the lateral direction along the surfaces of the half mirrors 44 and 45. Then, the concave mirror 4 is arranged so as to face the two-dimensional display elements 12 and 13 with the visual axis interposed therebetween.
6, 47 are arranged. The concave mirrors 46 and 47 are composed of eccentric surfaces whose center axes are the visual axes bent by 90 ° by the half mirrors 44 and 45, respectively.

Even in such an arrangement, the image of the two-dimensional display element 12 is transmitted through the half mirror 44 and the concave mirror 4
The image of the two-dimensional display element 13 is reflected by 6 and is then reflected by the half mirror 44, and the image of the two-dimensional display element 13 is transmitted through the half mirror 45, reflected by the concave mirror 47, reflected by the half mirror 45, and dividedly displayed. The images are optically combined into one continuous image for observation, and the joint can be eliminated. The concave mirrors 46 and 47 are decentered as described above so that the exit pupils from the two two-dimensional display elements 12 and 13 coincide with each other. The images displayed on the two-dimensional display elements 12 and 13 are vertically inverted.

In this arrangement, a polarization beam splitter prism is used as the beam splitter prism, and the λ / 4 plate 21 is arranged between the beam splitter prisms 41 and 42 and the concave mirrors 46 and 47 as in the sixth embodiment. The concave mirrors 46 and 47 are prisms 41 and 4,
It may be configured integrally with 2, or may be a separate body. Also,
The prisms 41 and 42 may be arranged in parallel in the vertical direction instead of in the horizontal direction. In this case, a wide angle of view can be obtained in the vertical direction. In this embodiment, the front surfaces of the prisms 41 and 42 are made to be transmissive surfaces, so that the two-dimensional display elements 12 and 13 can be easily superposed and observed with the external image.

Thirteenth Embodiment The thirteenth embodiment will be described with reference to the perspective view of FIG. This embodiment is basically the same as the twelfth embodiment, but half mirrors 14 and 15 are used instead of the beam splitter prisms 44 and 45. In the case of this embodiment, since no prism is used, it is light. In addition, since there is no surface on the visual axis that has power for the light coming from the outside world, the outside world image looks like a natural outside world. Further, since only one semi-transmissive surface is inserted for the external light, the brightness of the see-through image can be increased.

Fourteenth Embodiment A fourteenth embodiment will be described with reference to the perspective view of FIG. This embodiment is a modification of the twelfth embodiment. In this embodiment, instead of using two eccentric concave mirrors,
A single concave mirror 48 having the visual axis as the central axis is used. That is, in FIG. 18, the two-dimensional display elements 12, 13
Are arranged such that their display surfaces are offset from each other by a display screen and are substantially parallel to the visual axis of the user, and the beam splitter prisms 41 and 42 are arranged in parallel in the left-right direction intersecting the visual axis. And those half mirrors 44,
45 form an angle of approximately 90 ° with each other and an angle of approximately 45 ° with respect to the visual axis, and the prism 4
A concave mirror 48 is arranged in front of the visual axes of the lenses 1 and 42.

In this arrangement, the image of the two-dimensional display element 12 is reflected forward by the half mirror 44 and the concave mirror 4
Then, the image of the two-dimensional display element 13 is reflected forward by the half mirror 45, reflected by the concave mirror 48 and transmitted through the half mirror 44, and is divided and displayed. The images are optically combined into one continuous image for observation, and the joint can be eliminated. Also in this case, the images displayed on the two-dimensional display elements 12 and 13 are vertically inverted.

In this embodiment, unless the concave mirror 48 is a semi-transmissive mirror, the two-dimensional display elements 12 and 13 cannot be observed by superimposing the external image. In this case, since the number of parts is smaller than that in the twelfth embodiment, it is easy to manufacture.

Fifteenth Embodiment By the way, in each of the above embodiments, in order to prevent flare light, the planar wave plates 21 and 23 are provided in the concave mirror 1.
6, 28, 31 and the half mirrors 14, 15 or the prisms 27, 30, 41, 42. The wave plates 21 and 23 are curved wave plates 2 along the concave mirror 16.
By using 1'and 23 ', the entire apparatus can be downsized.

FIG. 19A is a diagram showing an example corresponding to the second and tenth embodiments, and the polarizer 20 and the like are not shown. As shown in this figure, by making the λ / 4 plate 21 'closely adhere to the concave mirror 16 as a curved surface, the thickness of the entire device can be reduced by the amount of the concave portion of the concave mirror 16, and the device can be made smaller. Can be converted.

FIG. 19 (b) is a diagram showing an example corresponding to the third embodiment. In this case, the wave plate 23 'made of quartz is similarly curved to be in close contact with the concave mirror 16 so that the concave mirror 16 is formed. The thickness of the entire device can be reduced by the amount corresponding to the lack of ball.

FIG. 19C is a diagram showing an example corresponding to the sixth to eighth embodiments. In these embodiments, the optical path is filled with a prism and a lens in order to shorten the optical path. However, since the concave mirror 16 and the λ / 4 plate 21 'are integrated, a lens having the concave mirror 16 as a rear surface mirror is unnecessary. The structure is simplified and the number of parts is reduced only by deforming the surfaces of the prisms 27, 30, 41, 42 on the concave mirror 16 side.

Sixteenth Embodiment A sixteenth embodiment will be described with reference to FIG. This embodiment is the same as the fifth and ninth embodiments except for a part. Therefore, only different parts will be described. 5 in the figure
Reference numeral 0 is a 66 ° prism, 51 is a V-shaped prism, and 16 is a concave mirror provided with a mirror coat. Similar to the sixth embodiment, the 66 ° prism 50 and the V-shaped prism 51 are cemented together to form one prism as a whole, and the cemented surfaces 54, 55 are provided with a half mirror coat. Joining surfaces 54, 55 with half mirror coating
Are V-shaped at an angle of 66 ° (α) with respect to each other. The corresponding points are located at 228 ° (β) across the ridge line L. Joining surface 5 with half mirror coat
By combining 4, 55 with an acute angle (α = 66 °) instead of a right angle, the light passing through the half mirror 54 or 55 and reflected by the next half mirror 55 or 54 is used according to the optical path indicated by the dotted line. Since it is out of the eyes of the person, it does not cause flare.

In the present embodiment, the pincushion-shaped image distortion caused by the concave mirror 16 has a convex aspherical surface 56 whose curvature gradually decreases as the distance from the optical axis increases.
It is corrected by applying it to the side surface.

By the way, when a pair of the optical system described in each of the above embodiments is prepared for the left and right eyes, the two-dimensional display elements 12 and 13 are arranged as shown in FIG. There is a method of vertically arranging the two, and a method of horizontally arranging as shown in FIG. 21 (a) and 22 (a), reference numeral 34 designates the entire optical system.
Indicates a backlight, and FIGS. 21 (b), (c),
22B and 22C respectively show the two-dimensional display element 1.
21 (d) and 22 (d) show composite images obtained by them.

In the method of vertically arranging as shown in FIG. 21A, since the images are combined vertically, the two-dimensional display element 1
As shown in FIGS. 21 (b) and 21 (c), a display element having a short top and bottom (shorter depth in FIG. 21 (a)) can be used as the reference numerals 2 and 13, and the effect of reducing the thickness of the entire device is great. . Moreover, as shown in FIG.
In the method of arranging the two-dimensional display elements 12 and 13 side by side, when the two-dimensional display elements 12 and 13 must be illuminated from the back side, two two-dimensional display elements 12 and 1 are formed by one light source.
3 can be illuminated at the same time (the backlight 36 in FIG. 22 (a) has two left and right two-dimensional display elements 12, 1).
Lighting 3 at the same time. ). Note that the arrangement of FIG. 22A has a wider angle of view in the left-right direction and is more natural.

By the way, the left and right optical systems 34, 34 are shown in FIG.
In the case of arranging horizontally as shown in FIG. 2 (a), as shown in the plan view of FIG. 23 (a), the left and right optical systems 34 _L and 34 _R are not arranged side by side in a straight line but each optical system. The exit optical axes of the systems 34 _L and 34 _R may be arranged so as to be tilted in the shape of “Λ” so as to enter the pupils of the left and right eyes from the outside of the left and right.
In FIG. 23A, the left eye optical system 34 _L has a two-dimensional display element 12 _L for displaying an image on the left side and a two-dimensional display element 13 _L for displaying an image on the right side. System 34
_The two-dimensional display element for displaying the image on the left side of _R is 12 _R , and the two-dimensional display element for displaying the image on the right side is 13 _{R. In} this embodiment, each two-dimensional display element 12 _L ,
3 _L , 12 _R and 13 _R are arranged so as to display a screen of 30 ° each. And the two-dimensional display element 13 _L ,
When the same image is displayed on 12 _R , the display screen of the entire device is displayed on the two-dimensional display element 1 as shown in FIG.
The display images of 3 _L and 12 _R overlap each other at the center, and 2 on the left side.
The display image of 12 _{L on} the dimensional display element and the display image of 13 _R on the two-dimensional display element spread to the right side of the display image.
It has a wide angle of view of 45 °. If the same image is displayed on the two-dimensional display elements 13 _L and 12 _R in this way, the electronic circuit becomes simple. The two-dimensional display element 13
Display an image with parallax on _L and 12 _R , and horizontal angle of view 90 °
It is also possible to perform a three-dimensional display.

The visual display device of the present invention has been described above based on some embodiments, but the present invention is not limited to these embodiments and various modifications can be made.

[0058]

As is apparent from the above description, according to the visual display device of the present invention, a head-mounted display capable of observing an image with a wide angle of view and high resolution while the optical system is downsized. A visual display device such as a device can be provided.

[Brief description of drawings]

FIG. 1 is a diagram showing a first basic form, a display image, and a composite image of a visual display device according to the present invention.

FIG. 2 is a diagram showing a second basic mode, a display image, and a composite image.

FIG. 3 is a diagram showing a third basic form, a display image, and a composite image.

FIG. 4 is a diagram showing a main part and an observed image of the first embodiment.

FIG. 5 is a partial cross-sectional view of a half mirror using a louver type filter substrate.

FIG. 6 is a diagram showing a main part of a second embodiment.

FIG. 7 is a diagram showing a main part of a third embodiment.

FIG. 8 is a diagram showing a main part of a fourth embodiment.

FIG. 9 is a diagram showing an essential part of a fifth embodiment.

FIG. 10 is a diagram showing a main part of a sixth embodiment.

FIG. 11 is a diagram showing an essential part of a seventh embodiment.

FIG. 12 is a diagram showing a main part of an eighth embodiment.

FIG. 13 is a diagram showing a main part of a ninth embodiment.

FIG. 14 is a diagram showing a main part, a display image, and a composite image of the tenth embodiment.

FIG. 15 is a diagram showing an essential part of the eleventh embodiment.

FIG. 16 is a perspective view showing a main part of a twelfth embodiment.

FIG. 17 is a perspective view showing a main part of the thirteenth embodiment.

FIG. 18 is a perspective view showing the main parts of the fourteenth embodiment.

FIG. 19 is a view showing the main parts of some forms of the fifteenth embodiment.

FIG. 20 is a diagram showing an essential part of the sixteenth embodiment.

FIG. 21 is a diagram showing a main part, a display image, and a combined image in the case of a vertical arrangement.

FIG. 22 is a diagram showing a main part, a display image, and a combined image in the case of a horizontal arrangement.

FIG. 23 is a diagram showing a main part of a horizontal array modification and a composite display screen.

FIG. 24 is a diagram showing a main part of one conventional head-mounted display device.

FIG. 25 is a front view of a single liquid crystal display device.

[Explanation of symbols]

4, 5 ... Two-dimensional display element 6, 7 ... Half mirror 8 ... Concave mirror 8 '... Convex lens 9 ... Overlap area 10, 11, 10', 11 ', 10 ", 11" ... Display image 12, 12 _L , 12 _R , 13, 13 _L , 13 _R ... Two-dimensional display element 14, 15 ... Half mirror 16 ... Concave mirror 17 ... Translucent hole 18 ... Shading wall 19 ... Half mirror coat 20 ... Polarizer 21, 21 '... λ / 4 plate 22 ... analyzer 23, 23 '... wavelength plate 24 ... convex lens 25 ... decentered aspherical concave lens 26 ... triangular prism 27 ... V prism 28 ... concave mirror 29 ... triangular prism 30 ... V prism 31 ... concave mirror 32,33 ... half mirror 34, 34 _L, 34 _R ... display optics 35, 36 ... backlight, 39 ... total reflecting mirror 40 ... lens 41 ... beam splitter prism 4, 45 ... Half mirror 46, 47, 48 ... Concave mirror 50 ... 66 ° prism 51 ... V-shaped prism 54, 55 ... Half mirror coat bonding surface 56 ... Aspheric surface A, A ', B, B' ... Two-dimensional display element Display surface area P1 to P4 ... Observation image p1 to p4, p1 'to p4' ... Display point L ... Ridge line

Claims (6)

[Claims] 1. A visual display device comprising a two-dimensional display means and an eyepiece optical system which projects an image formed by the two-dimensional display means and guides the image to an observer's eyeball. A first image display means for displaying at least a part of the image guided to the observer's eye, and a second image display means for displaying the image display part including another part different from the image display part, Further, the eyepiece optical system has a first reflecting surface for reflecting the first image formed by the first image display means and a second reflecting surface for reflecting the second image formed by the second image display means. And a second reflection surface, and an optical system having a positive power for projecting a combined image of the first image and the second image in an enlarged manner by projecting the combined image into the observer's eyeball. On the other hand, the second reflecting surface is arranged at an angle. A visual display device characterized by being placed. 2. The first reflection surface and the second reflection surface are both arranged between the first image display means and the second image display means. 1. The visual display device according to 1. 3. The visual display device according to claim 1, wherein the optical system having the positive power is a concave mirror. 4. The visual display device according to claim 1, wherein the optical system having the positive power includes a wave plate having a curved surface shape. 5. An optical system having an external optical path that passes through at least one of the first reflecting surface and the second reflecting surface or between them, and the optical system having the positive power is the first image display means and the first image display means. Two units corresponding to the two image display units are provided, and the first image display unit and the second image display unit, and the two optical systems having the positive power are arranged across the external optical path. The visual display device according to claim 1, wherein: 6. The visual display device according to claim 5, wherein the combined power of the optical systems provided on the external optical path is substantially zero.