JPH1020246A - Stereoscopic picture display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stereoscopic picture display device easy to observe without requiring spectacles by improving the installing constitution and the optical characteristics of both microlens arrays for a picture display panel. SOLUTION: This device is provided with a microlens array 110 arranged on the front side of the picture display panel 100 and the microlens array 120 arranged on the front side of the microlens array 110. In this case, the picture of the picture display panel 100 is displayed as two videos having different parallax by passing through both microlens arrays 110 and 120. Then, the microlens array 120 is at the position of mutually conjugating relation with the picture display panel 100 with respect to image-formation in the vicinity of a lens center surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a stereoscopic video display device.

[0002]

2. Description of the Related Art At present, a stereoscopic image display apparatus does not require stereoscopic glasses such as a liquid crystal shutter system or a polarizing system, and a stereoscopic glasses system such as a parallax barrier system or a lenticular system. There is a method. here,
Since the method using glasses has an unpleasant feeling for wearing glasses and a problem in hygiene, practical use of a method that does not require glasses is required.

In response to this request, a stereoscopic image display device using an image splitter system belonging to a parallax barrier system has been developed in a system which does not require glasses (Electronic technology published by Nikkan Kogyo Shimbun, 1995-
12, pp. 79-83). In this image splitter method, an image splitter is used in which a black linear pattern having a light-shielding property is formed in a flat shape on a glass substrate at regular intervals, and this image splitter displays images for the right eye and the left eye. Installed in front of the video panel.

[0004] Thus, an observer can see images having different parallaxes with the right and left eyes through each linear pattern of the image splitter. Here, when the observer observes the stereoscopic video display device at the optimal observation position and observes the stereoscopic image when the observer moves left and right, the right and left limit is defined as a stereoscopically viewable range.
And the wider the stereoscopic viewable range is, the easier it is to observe the stereoscopic video display device.

[0005] In this image splitter system,
When the horizontal aperture ratio of the image splitter is set to be small so that the stereoscopic viewable range is maximized, the brightness of the screen of the stereoscopic video display device becomes about 60% as compared with the case where the aperture ratio is sufficiently increased. For this reason, the rate at which the brightness of the screen decreases is reduced by narrowing the stereoscopic viewable range.

Next, the principle of the lenticular system is shown in FIG. In this figure, reference numeral 1000 denotes a panel on which pixels are arranged. Reference numeral 1010 indicates a glass substrate, and reference numeral 1020 indicates a lenticular lens. In panel 1000, R and L indicate pixels for the right and left eyes, respectively. Lenticular lens 102
Numeral 0 denotes a sheet in which cylindrical lenses are arranged in a sheet shape. Each lens 102 constituting the lenticular lens 1020
0a exerts an effect of separating the image by the right-eye pixel and the left-eye pixel so that the image can be seen by the right eye and the left eye, respectively.

FIG. 12 shows a case where an image is displayed on a liquid crystal panel with respect to the pixel arrangement of the lenticular type stereoscopic image display apparatus having the above-described configuration. Here, FIG.
(A) is a right-eye pixel 1100R and a left-eye pixel 110
The figure shows that 0L is alternately arranged. FIG. 12B shows a set of both pixels 1100R and 1100L.

In each pixel 1100R, 1100L, R (red), G (green), and B (blue) liquid crystal cells 1110R, 1110G, and 1110B corresponding to the three primary colors of light are arranged. The observer has the reference numerals 1120R, 112
A stereoscopic image is recognized by seeing light from a region indicated by a band with 0L with the right eye and the left eye, respectively. Here, an area having a width indicated by reference numeral 1130 is a black area that does not emit light. It should be noted that the contents shown in FIG. 12 are substantially the same in the case of the stereoscopic video display device using the image splitter method.

[0009]

By the way, in the image splitter system and the lenticular system, when the observer moves left and right, the band-like regions 1120R and 1120L also move right and left on the liquid crystal panel. For this reason, the arrangement of the liquid crystal cells 1110R, 1110G, and 1110B is such that each of the band-shaped regions 1120R, 1110G, 111
It is limited to an arrangement that equally covers 0B.

Therefore, each of the band-shaped regions 1120R, 1120
When the width of L is equal to each liquid crystal cell 1110R, 1110G, 1110
When the width is smaller than the width in the left-right direction of B, the brightness of the screen is reduced, and the brightness becomes constant when the observer moves left and right because each of the band-shaped regions 1120R and 1120L is within the width of the liquid crystal cell. Limited to certain cases. Further, the width of each of the band-shaped regions 1120R and 1120L is set to be equal to the width of each liquid crystal cell
When the observer moves to the left and right when the width is equal to the width of R, 1110G, and 1110B, the black area 1130 is included in each of the band-shaped areas 1120R and 1120L, so that the screen brightness decreases.

Further, each of the band-shaped regions 1120R, 1120L
Of each liquid crystal cell 1110R, 1110G, 1110B
Is wider than the width in the left-right direction, the brightness becomes constant when the observer moves left and right, because each band-shaped region 1120R,
It is limited when 1120L includes the liquid crystal cell width.
Further, the stereoscopically viewable range is narrowed until each of the band-shaped regions comes into contact with an adjacent pixel.

For this reason, in the conventional method, as described above,
The width of each band-shaped region 1120R, 1120L is set to be smaller than the width of each liquid crystal cell 1110R, 1110G, 1110B in the left-right direction. As described above, in the conventional method, the light from the entire surface of the region from which the light of each pixel emits light is not observed.
The condition that the brightness of the screen is reduced, the stereoscopically visible range is reduced under the condition that the brightness of the screen is kept constant, and the arrangement of RGB cells is limited when displaying a color image. This causes a problem.

Further, in the conventional method, since a lenticular lens or an image splitter is used, it is possible in principle to display two or more images having different parallaxes on the left and right. If the camera moves, there is a disadvantage that different images cannot be displayed. In view of the above, the present invention provides a stereoscopic image display device that does not require glasses and is easy to observe by devising the installation configuration and optical characteristics of the two microlens arrays with respect to the image display panel in order to deal with the above. The purpose is to do.

[0014]

According to the first to seventh aspects of the present invention, in order to achieve the above object, the second microlens array is provided with an image display for image formation near the first main surface. It is in a conjugate position with the panel. This means that the observer can see the light from the entire surface of each pixel of the image display panel using the second and first microlens arrays.

Therefore, even when the observer moves, the stereoscopically viewable range can be expanded without observing the region between the pixels which does not emit light and without changing the brightness. Here, according to the second aspect of the present invention, the focal length of each micro lens constituting the second micro lens array is f _2, and the distance between the first and second micro lens arrays is a. Then, the focal length f ₂ becomes
Expression

[0016]

Satisfies na / (n + 1) ≦ f ₂ ≦ na / (n−1). Thereby, the function and effect of the invention described in claim 1 can be further enhanced. According to the invention of claims 8 to 12, the number of images having different parallaxes is n (≧ 2) in the horizontal direction and m (≧ 1) in the vertical direction,
The microlens array is in a position conjugate with the image display panel with respect to imaging near the first main surface.

According to this, the function and effect described in the first aspect can be achieved not only for displaying a stereoscopic image viewed from the vertical direction but also to the horizontal direction. Here, as in the ninth aspect of the present invention, if the same configuration as that of the second aspect of the invention is adopted in the eighth aspect of the invention, the operation and effect of the eighth aspect of the invention can be reduced. Can be even higher.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. According to the present invention, a microlens array A (corresponding to a first microlens array) and a microlens array B (corresponding to a second microlens array) are conceptually installed on an image display panel. An image of a pixel is projected onto the first main surface of the microlens array B, and a plurality of pixels having different parallaxes are projected onto substantially the same area of the microlens array B by each microlens of the microlens array A. It is. Thus, the observer can observe the entire light emitting region of each pixel through both the micro lens arrays A and B. Hereinafter, details of the present invention will be described. (First Embodiment) FIG. 1 shows the basic principle of a stereoscopic video display apparatus according to the present invention as a first embodiment in the case of using two different parallaxes on the left and right.

In FIG. 1, reference numeral 100 denotes an image display panel, and both reference numerals 105R and 105L denote a right-eye pixel and a left-eye pixel, respectively. Also, each code 110
R and 110L are microlenses constituting the microlens array 110, and reference numeral 120 is a microlens. Reference numeral 115R denotes a lens center axis of the micro lens 110R, and reference numeral 115L denotes a micro lens 110R.
5 shows the lens center axis of L.

Here, the refractive index of the medium other than the microlenses is 1. In each of the pixels 105R and 105L, a mark “■” and a mark ● indicate an end of each pixel, and the micro lens 120
■ and ● in FIG. 3 indicate the end of the lens action area.
Further, the positions and the focal lengths of the micro lenses 110R and 110L are determined so that the respective images of the pixels 105R and 105L are projected on the first main surface of each micro lens 120. That is, each ■ in both pixels 105R and 105L
The positions of the ends indicated by the marks and ● are in a conjugate relationship with the positions of the ends indicated by the Δ and ● marks of the microlens 120. In addition, the mark 105 and the mark ● of the microlens 120 are connected to the pixel 105R by straight lines so that the center of the microlens 110R coincides with the intersection of these two straight lines. The center position of the microlens 110L is determined similarly.

The distance between the micro lens 120 and the micro lens 110R is represented by a, and the micro lens 1
When the distance between 10R and the image display panel is b,
The focal length f ₁ of the micro lens 110R is defined by two equations of the following Equation 4 and Equation 5.

[0022]

## EQU4 ## a = kb

[0023]

## EQU5 ## where (1 / a)-(1 / b) = (1 / f ₁ ) where, in the equation (4), the symbol k indicates a constant. Here, if black display due to the region between pixels does not matter, k may be set to 2. If black display is a problem, the value of k is determined so as to be equal to the ratio of the width of the lens working area of the microlens 120 to the width of the light emitting area in each pixel. In this case, the value of k is usually 2 or more.

The focal length of the micro lens 110L is also f ₁
And The focal length of the micro lens 120 is f ₂ ,
FIG. 1 shows a case where f ₂ = a. When the stereoscopic video display device according to the present invention is viewed from the front, the right eye has a chief ray 1
The light almost parallel to 30R can be seen, and the principal ray 130L to the left eye.
You can see light that is almost parallel to. These lights are lights emitted from the entire surface of each of the pixels 105R and 105L.

Next, in the three-dimensional image display device, the range in which stereoscopic viewing is possible becomes a problem. Assuming that the observer is at the optimal observation position Zm, the state of the light beam in the image display device in the stereoscopically viewable range Ld when the observation position moves in the left-right direction (vertical direction in FIG. 1) is shown in FIG. For
As shown in FIG. FIG. 2 shows the case of the right eye. Note that a light ray passing through the center of the micro lens 120 is called a principal ray.

When there is a relation of f ₂ = a, the case where the principal ray entering the right eye passes through both ends of the microlens 110R limits the stereoscopic vision. Therefore, when the width of the micro lens 110R is d (see FIG. 2), the stereoscopically viewable range is given by the following equation (6).

[0027]

Ld = Zm × (d / f ₂ ) In this stereoscopically viewable range, since both the pixels 105R and 105L are projected on the surface of the microlens 120, the observer moves right and left. Also, each pixel 105R,
It is possible to see an image almost equivalent to the case of viewing the entire surface of 105L, and the brightness of the image is almost constant. In addition, since the entire surface of each of the pixels 105R and 105L is viewed,
In each of the pixels 105R, 105L, etc., the arrangement for each of the RGB liquid crystal cells (corresponding to each image panel) can be freely set.

Next, when 2a ≧ f ₂ ≧ a, when Ld is obtained geometrically, Ld is given by the following equation (7).

[0029]

Ld = Zm ｛{2− (f ₂ / a)} (d / f ₂ ) In the case of f ₂ > 2a, the right-eye video and the left-eye video are in a mixed state. Unsuitable for viewing. next,
In the case of (2a / 3) ≦ f ₂ ≦ a, when Ld is obtained from geometrical optics, this Ld is given by the following equation 8.

[0030]

Ld = Zm · {(3 · f ₂ / a) −2} (d / f ₂ ) Note that when f ₂ <(2a / 3), the right-eye and left-eye images are mixed. It is in a state of fitting and is unsuitable for stereoscopic vision.
From the above, the condition of f ₂ for obtaining the stereoscopic vision is as follows:
Given by the equation

[0031]

(2a / 3) ≦ f ₂ ≦ 2a The condition for maximizing the stereoscopically viewable range is as follows:
Given by the equation

[0032]

F ₂ = a Next, the principle of using three images having different parallaxes will be described with reference to FIG. In this figure, reference numeral 300 indicates an image display panel, and reference numerals 305A, 305B, 305
C indicates a pixel having parallax. The pixel 305A is configured to be viewed with the right eye, the pixel 305B is viewed with the left eye, the pixel 305B is viewed with the right eye, and the pixel 305C is viewed with the left eye.

Each of the reference numerals 310A, 310B, 310
C is a micro lens constituting the micro lens array 310, and reference numeral 320 is a micro lens. In each of the pixels 305A, 305B, and 305C, the symbol ■ and the symbol ● indicate the end of each pixel, and the symbol ■ in the microlens 320 indicates the edge of the lens action region. Also, each microlens 310A is set so that the position of the end of each pixel 305A, 305B, 305C indicated by a triangle and the mark ● has a conjugate relationship with the position of the end of the microlens 320 indicated by the mark Δ and ●. , 310B, 310C and the focal length are determined. The principle of the configuration shown in FIG. 3 is the same as the principle described in FIG.

In FIG. 3, each micro lens 310
A, 310B, the focal length of 310C and f _1, the focal length of the microlens 320 and f _2. Micro lens 320 and each micro lens 310A, 310B, 31
A is the distance between the micro lens 310 and the micro lens 310.
The distance between A, 310B, 310C and image display panel 300 is assumed to be b.

Under this assumption, the focal length f ₁ is calculated by the above equation (4).
And equation (5). If black display is not a problem, k may be set to 3. The range of the focal length f ₂ for obtaining stereoscopic vision is (3a / 4) ≦ (f ₂ ) ≦ (3a / 2), and the condition for maximizing the stereoscopic viewable range is f ₂ = a. In the above, two images having different parallaxes and three
Although the case where one is used has been described, the position and the focal length of each microlens can be similarly determined when there are four or more images having different parallaxes.

As shown in FIG.
D is the width of the elementary region_PAnd emit light in this pixel area
The width of the region to be_LAnd images with different parallax in the left and right directions
Is n. Left of the micro lens on the image display panel side
Right width is D_PThe left and right sides of the micro lens on the observer side
Direction width is nD_PTo be equal to Image display panel
In the projection of the lens on the surface of the observer side micro lens,
Magnification of projected image by micro lens on image display panel side
Is k. k is n to n (D _P/ D_L) Value
In particular, k = n (D_P/ D_L), Pixels and images
It is possible to avoid black display due to areas between pixels. Picture
Focal length f of image display panel side micro lens₁Is the above number
It can be determined from Equations 4 and 5.

The condition of the focal length f ₂ of the micro lens on the observer side that enables stereoscopic viewing is given by the following equation (11).

[0038]

{Na / (n + 1)} ≦ f ₂ ≦ {na / (n−1)} Further, the condition for maximizing the stereoscopic viewable range is f ₂ = a. In this case, regardless of the value of n, the observer sees the entire surface of each pixel corresponding to the parallax in the stereoscopically viewable range through the panel-side microlens and the observer-side microlens. For this reason, the image can be viewed with the same brightness as when a normal image display panel is viewed, and without changing the brightness even when the display panel is moved right and left.

In the production of a stereoscopic video display device, since the area of each pixel is viewed as it is, the RGB
There is no need to set restrictions or conditions on cell placement methods. Therefore, liquid crystal panels, electroluminescence (EL)
Panel, plasma display panel, cathode ray tube (C
A stereoscopic image display device can be realized by combining an image display panel for RT), printed matter, photograph, etc. with two sets of microlens arrays according to the present invention.

Further, when a normal two-dimensional image without parallax is displayed, the observer sees the image projected on the microlens on the observer side. Can be. In addition, since the range of the pixel area projected on the observer side microlens can be limited, the black area between pixels can be made invisible to the observer, and high quality image quality can be obtained. Can be obtained. (Second Embodiment) FIG. 5 shows a specific embodiment of a stereoscopic video display apparatus according to the present invention as a second embodiment.

In the second embodiment, the stereoscopic video display device stereoscopically views two images having different parallaxes.
FIG. 5 shows a cross section of this stereoscopic image display device on a horizontal plane. In FIG. 5, reference numeral 400 denotes an image display panel, and reference numeral 410 denotes a glass substrate provided on the front surface of the image display panel. Reference numeral 420 indicates a microlens array corresponding to the microlens array A, and reference numeral 430 indicates a microlens array corresponding to the microlens array B. Reference numeral 440 denotes a glass substrate on which both the micro lens arrays 420 and 430 are formed.

Each of the reference numerals 400R and 400L represents
This shows a pixel area in which right-eye and left-eye pixels are present. Each of the reference numerals 420R and 420L represents a microlens array 420.
Are shown, and these micro lenses 420R and 420L are respectively provided in the pixel region 4
This is a micro lens for 00R and 400L. Reference numeral 430a indicates one micro lens of the micro lens array 430, and micro lenses 420R and 420L correspond to each micro lens 430a. Each of the micro lens arrays 420 and 430 is constituted by a cylindrical lens.

In the case where the pixel is small and black display is not a problem, that is, when k = 2, specific dimensions and the like of the second embodiment are shown. Each pixel region 400R, 400L
Are 150 μm, respectively, and the glass substrate 41
0 is 0.85 mm, and the thickness of the glass substrate 440 is 1.7 mm. In addition, each glass substrate 410, 4
40 has a refractive index of 1.5.

Each microlens array 420, 430
Is formed of an optical plastic having a refractive index of 1.8. In each of the micro lenses 420R and 420L,
Each has a width of 150 μm and a focal length f ₁ of 5 μm.
67 μm, and the distance from the lens center axis of each microlens 430a to the lens center axis is 50 μm. The radius of curvature of the cylindrical surface is set to 113 μm in order to obtain f ₁ = 567 μm. In the microlens array 420, each microlens is arranged at a pitch of 150 μm.

In the micro lens 430a,
The width is 300 μm and the focal length f _TwoIs 1.7 mm
You. Also, f_Two= Curve of cylindrical surface to obtain 1.7mm
The rate radius is 340 μm. Micro lens array
In 430, each micro lens is arranged at a pitch of 300 μm.
It is. When the human eye-to-eye distance is 65 mm,
The observation distance Zm is 489 mm, and the stereoscopically viewable range Ld is
65 mm.

Even when k> 2, it is clear that the stereoscopic image display device according to the present invention can be constructed in the same manner as described in the principle of the first embodiment. Here, examples of the arrangement of the RGB cells in each pixel which are possible in the stereoscopic image display device according to the present invention are shown in FIGS.
If each pixel corresponds to each microlens, the RGB cells may be arranged in any manner in each pixel.

In the second embodiment, the configuration is as described above. Therefore, as described in the first embodiment (see FIG. 1), the right eye is viewed from the entire surface of each pixel region 400R. The image can be seen by light, and the left eye is each pixel area 4
An image can be viewed by light from the entire surface of 00L.
For this reason, the degree of freedom for the arrangement method of the RGB cells in each pixel region is large, and the brightness of the video display device hardly changes within the stereoscopically viewable range. (Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIG.

In the third embodiment, unlike the second embodiment, which is directed to two images having parallax, a three-dimensional image display apparatus which targets three images each having parallax is provided. explain. In FIG.
Reference numeral 00 denotes an image display panel, and reference numeral 510 denotes a glass substrate on the front surface of the image display panel 500. Reference numeral 52
0 indicates a micro lens array corresponding to the micro lens array A, and reference numeral 530 indicates a micro lens array corresponding to the micro lens array B.

Reference numeral 540 denotes a glass substrate on which the microlens arrays 520 and 530 are formed. 5 each
00A, 500B, and 500C indicate pixel regions in which pixels having parallax exist, respectively. Each symbol 520A, 5
Reference numerals 20B and 520C denote microlenses constituting the microlens array 520, and these microlenses 520A, 520B and 520C are microlenses for the pixel regions 500A, 500B and 500C, respectively.

Reference numeral 530a denotes the micro lens array 53.
0 indicates one micro lens, and each micro lens 5
30a, each micro lens 520A, 520B, 5
20C correspond to each other. The micro lenses of each of the micro lens arrays 520 and 530 are constituted by cylindrical lenses. Specific dimensions and the like of the third embodiment will be described for the case where the pixels are small and black display is not a problem, that is, when k = 3.

Each pixel area 500A, 500B, 500C
Are 150 μm, respectively, and the glass substrate 51
0 is 0.85 mm, and the thickness of the glass substrate 540 is 2.55 mm. In addition, each glass substrate 510,
The refractive index of 540 is 1.5. Each of the micro lens arrays 520 and 530 is formed of an optical plastic having a refractive index of 1.8.

Each micro lens 520A, 520B, 5
In 20C, the width is 150 μm and the focal length f ₁ is 638 μm. The distance from the lens center axis of the micro lens 530a to the lens center axis is 0 for the micro lens 520B and 112.5 μm for the micro lenses 520A and 520C. The radius of curvature of the cylindrical surface is set to 128 μm in order to obtain f ₁ = 638 μm. In the microlens array 520, the microlenses are arranged at a pitch of 150 μm.

In the micro lens 530a,
The width is 450 μm and the focal length f _TwoIs 2.55mm
is there. f_Two= Half the curvature of the cylindrical surface to obtain 2.55 mm
The diameter is 510 μm. Micro lens array 5
At 30, microlenses are arranged at a pitch of 450 μm
You. If the distance between human eyes is 65 mm, the optimal observation distance
Zm is 735 mm, and the stereoscopic viewable range Ld is 65 m.
m.

In the third embodiment, since the configuration is as described above, when the stereoscopic image display device is observed at the optimum observation distance, when the image from the pixel region 500A is viewed by the right eye, the pixel is displayed by the left eye. You can see the video from the area 500B,
Also, when viewing the image from the pixel area 500B with the right eye,
An image from the pixel area 500C can be seen by the left eye. In this manner, two types of stereoscopic images can be observed on the same image display device. In any case, the image viewed by the right eye or the left eye corresponds to each pixel area 500A, 500A.
B, composed of light from the entire surface of 500C. Therefore, the degree of freedom in the arrangement method of the RGB pixels in each pixel region is large, and the brightness of the video display device hardly changes within the stereoscopically viewable range. (Fourth Embodiment) FIGS. 8 to 10 show a fourth embodiment of the present invention.

In the fourth embodiment, three different fields of view are used.
A three-dimensional image display device that uses × 3 images will be described. FIG. 8 shows an arrangement of pixels for 3 × 3 different fields of view. In this figure, pixels having the same sign display image information for the same field of view. FIG. 9 shows a cross section of the stereoscopic image display device in a horizontal plane, and FIG. 10 shows a cross section of the stereoscopic image display device along a vertical plane. Reference numeral 600 indicates an image display panel, and reference numeral 610 indicates a glass substrate. Reference numeral 620 indicates a microlens array corresponding to the microlens array A, and reference numeral 630 indicates a microlens array corresponding to the microlens array B. Reference numeral 640 denotes each microlens array 6.
6 shows a glass substrate forming 20, 630.

Here, specific dimensions and the like of the fourth embodiment will be described for the case where the pixels are small and black display is not a problem. The size of each pixel A1 to C3 is 150 μm × 1
50 μm. The thickness of the glass substrate 610 is 0.85 m
m, and the refractive index of each of the glass substrates 610 and 640 is 1.
5 Each microlens array 620, 630
Is formed of an optical plastic having a refractive index of 1.8. The thickness of the glass substrate 640 is 2.55 mm.

The microlenses constituting the microlens array A620 are convex lenses having a spherical surface and a flat surface, and have dimensions of 150 μm × 150 μm. Also,
The radius of curvature of the spherical surface of this microlens is 128 μm. Each micro lens constituting the micro lens array 630 is a convex lens composed of a spherical surface and a flat surface, and its size is 450 μm × 450 μm. The radius of curvature of the spherical surface of each micro lens of the micro lens array 630 is 510 μm.

A microlens of the microlens array 630 corresponds to a 3 × 3 microlens of the microlens array 620. Microlens array 62 for axis
The positional relationship between the central axes of the 3 × 3 microlenses constituting 0 is determined by applying the method described in the principle of the first embodiment in the horizontal and vertical directions.

In the fourth embodiment, as described in the principle of the first embodiment, a three-dimensional image display device is constructed. It is possible to observe a stereoscopic image viewed from the right, above, and below. For example, in FIG.
1 to A3, B1 to B3, and C1 to C3 indicate images with different line-of-sight heights, respectively, and if symbols B1 to B3 indicate a case where the line of sight is viewed horizontally, the symbols A1 to A3 are from below. The images viewed are shown, and reference numerals C1 to C3 indicate images viewed from above.

When the observation position is moved right and left while keeping the line of sight horizontal, a three-dimensional image by the symbols B1 and B2 or a three-dimensional image by the symbols B2 and B3 can be seen. If you look at the video display from above,
Alternatively, in the case where the image display device is tilted to the front, when the position to be observed is moved left and right, a stereoscopic image by the symbols C1 and C2 or a stereoscopic image by the symbols C2 and C3 can be seen.

When the image display device is viewed from below, or when the image display device is tilted backward, when the observation position is moved right and left, a three-dimensional image by each of the symbols A1 and A2 or each of the symbols A2 and A3 is obtained. Can see a stereoscopic image. At this time, since the light from the entire surface of each pixel reaches the observer through each of the micro lens arrays 620 and 630, the brightness is not impaired.

In each of the second to fourth embodiments described above, the case where the number of images having different visual fields is two, three, and 3 × 3 has been described. Even in the case of N (≧ 2) and N × M of M (≧ 1) in the vertical direction, the stereoscopic image display device according to the present invention is realized by the method described in the second to fourth embodiments. Can be. In the second and third embodiments, the microlenses constituting the microlens array A are cylindrical lenses, but spherical lenses may be used.

In each of the second to fourth embodiments, the case where the pixel size is specified has been described. However, the method described in the second to fourth embodiments can be applied to other pixel sizes. , Each micro lens array A, B
Can be designed, and the stereoscopic video display device according to the present invention can be realized.

[Brief description of the drawings]

FIG. 1 is an optical schematic diagram illustrating a principle of a three-dimensional image display device according to the present invention as a first embodiment when two images having different parallaxes are used.

FIG. 2 is a schematic diagram showing directions and ranges of light rays in a stereoscopically viewable range according to the above principle.

FIG. 3 is a diagram showing three images having different parallaxes in the first embodiment.
FIG. 2 is an optical schematic diagram showing the principle of using one.

FIG. 4 is a schematic diagram illustrating a width of a pixel region in the first embodiment.

FIG. 5 is a schematic sectional view of a stereoscopic image display device according to a second embodiment of the present invention.

FIGS. 6A to 6D are schematic diagrams showing modifications of the third embodiment, respectively.

FIG. 7 is a schematic sectional view of a stereoscopic image display device according to a third embodiment of the present invention.

FIG. 8 is a schematic diagram showing an arrangement of pixels for 3 × 3 different fields of view of a stereoscopic image display device according to a fourth embodiment of the present invention.

FIG. 9 is a diagram showing a cross section in a horizontal plane of the stereoscopic video display device.

FIG. 10 is a diagram showing a cross section of the stereoscopic image display device taken along a vertical plane.

FIG. 11 is an optical schematic diagram showing the principle of a conventional lenticular type stereoscopic image display device.

FIGS. 12A and 12B are schematic diagrams illustrating the principle of a lenticular-type stereoscopic image display device.

[Explanation of symbols]

100, 300, 400, 500, 600 ... image display panel, 105R, 105L, 305A, 305B, 305C ...
Pixels, 110R, 110L, 120, 310A, 310B, 3
10C, 320, 430a, 420R, 420L: Micro lens, 115R, 115L: Lens central axis of micro lens, 110, 310, 420, 430, 520, 530, 6
20, 630... Microlens array.

Claims (12)

[Claims] An image display panel (100, 300, 40)
0, 500, 600) and a first microlens array (110, 310, 420, 520, 62) disposed in front of the image display panel.
0) and a second micro lens array disposed in front of the first micro lens array.
Micro lens array (120, 320, 430, 53
0, 630), wherein the image of the image display panel is displayed as n (≧ 2) images having different parallaxes through the first and second microlens arrays. A three-dimensional image display device, wherein the second microlens array is located at a position in a conjugate relationship with the image display panel with respect to imaging near the first main surface. 2. When the focal length of each microlens constituting the second microlens array is f ₂ and the distance between the first and second microlens arrays is a, the focal length f _2. The stereoscopic image display device according to claim 1, wherein ₂ satisfies the following equation (1): na / (n + 1) ≦ f ₂ ≦ na / (n−1). 3. The three-dimensional image display device according to claim 2, wherein f ₂ = a. 4. The center of each micro lens constituting the first micro lens array is on a straight line connecting positions conjugate with each other in the image display panel and the second micro lens array. The stereoscopic video display device according to any one of claims 1 to 3. 5. The micro lenses constituting the first micro lens array are arranged such that an image of the image display panel is provided on the first main surface of the second micro lens array at a magnification of n or more with respect to the image display panel. The stereoscopic video display device according to any one of claims 1 to 4, wherein the stereoscopic video display device is located at a projection position. 6. The image display panel has Np pixels, the number of microlenses forming the first microlens array is Np or more, and the number of microlenses forming the second microlens array is The three-dimensional image display device according to claim 1, wherein the number is (Np / n) or more. 7. Each of the microlenses constituting the first and second microlens arrays is a cylindrical lens, and the second microlens array comprises n microlenses constituting the first microlens array. The three-dimensional image display device according to claim 1, further comprising one microlens. 8. An image display panel (100, 300, 40)
0, 500, 600), a first microlens array (110, 420, 520, 620) disposed in front of the image display panel, and a second microlens array disposed in front of the first microlens array.
Micro lens array (120, 430, 530, 63
0), wherein the image of the image display panel is displayed through the first and second microlens arrays as a plurality of images having different parallaxes. Number is n (≧ 2) in the horizontal direction
M (≧ 1) in the vertical direction, wherein the second microlens array is in a position conjugate with the image display panel with respect to imaging near the first main surface. 9. When the focal length of each micro lens constituting the second micro lens array is f ₂ and the distance between the first and second micro lens arrays is a, the focal length f _2, the stereoscopic image display apparatus according to claim 8, characterized by satisfying the following expression 2 equation 2] na / (n + 1) ≦ f 2 ≦ na / (n-1). 10. The three-dimensional image display device according to claim 9, wherein f ₂ = a. 11. The center of each micro lens constituting the first micro lens array is on a straight line connecting positions conjugate with each other in the image display panel and the second micro lens array. Claim 8
11. The stereoscopic video display device according to any one of claims 10 to 10. 12. The microlens array according to claim 1, wherein the first microlens array has a microlens for every pixel for every pixel, and the second microlens array has one microlens for every n × m. Claims 8 to 11
The stereoscopic video display device according to any one of the above.