JP2013142743A - Stereoscopic image photographing device and stereoscopic image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stereoscopic image photographing device and a stereoscopic image display device which can obtain a stereoscopic image in which a vias in definition is reduced or eliminated in integral photography.SOLUTION: A stereoscopic image photographing device includes a lens array 110 constituted by two-dimensionally arraying a plurality of element lenses, and an imaging section 130 for receiving a luminous flux obtained through the lens array 110 at an imaging surface having pixel structure according to ray density of each element lens of the lens array 110 so as to take an image and for generating integral image data which are a collection of element images corresponding to each of the plurality of element lenses.

Description

  The present invention relates to a stereoscopic image capturing apparatus and a stereoscopic image display apparatus.

  Integral photography is known as one of the aerial image reproduction methods (see, for example, Patent Document 1). A photographing apparatus to which this integral photography is applied photographs a subject via a lens array configured by two-dimensionally arranging minute element lenses to generate an integral image. A display device to which integral photography is applied displays an integral image on a display surface to generate a light beam, and passes this light beam through a lens array to generate a three-dimensional image in space. That is, integral photography is a reproduction method that generates an image of light so that the light flux coming from the display surface of the display device is the same as the light flux coming from the actual subject.

JP 2001-228570 A

In conventional photography integral photography, the width of a light beam obtained from an object through an element lens changes according to the incident angle with respect to the element lens. Therefore, the density of the light beam applied to the imaging surface of the image sensor is not uniform. Further, in the conventional integral photography of a display system, the width of the light beam obtained from the display surface through the element lens changes according to the incident angle with respect to the element lens. Therefore, the density of the light beam obtained from the display surface through the element lens is not uniform.
The present invention has been made to solve the above-described problem, and provides a stereoscopic image photographing apparatus and a stereoscopic image display apparatus capable of obtaining a stereoscopic image with reduced or eliminated definition bias in integral photography. The purpose is to provide.

[1] In order to solve the above-described problem, a stereoscopic image capturing apparatus according to an aspect of the present invention includes a lens array configured by two-dimensionally arranging a plurality of element lenses, and a light beam obtained through the lens array. An imaging unit that receives and captures an image on an imaging surface having a pixel structure corresponding to the light density of each element lens in the lens array, and generates an integral image that is a set of element images corresponding to each of the plurality of element lenses; It is characterized by providing.
[2] The stereoscopic image capturing apparatus according to [1], wherein the imaging unit receives and captures the light flux on an imaging surface with larger pixels as the light density of each element lens is higher. .
[3] In order to solve the above problems, a stereoscopic image display device according to an aspect of the present invention is a stereoscopic image display device including a lens array configured by two-dimensionally arranging a plurality of element lenses. And a display unit configured to display an integral image, which is a set of a plurality of element images, on a display surface having a pixel structure corresponding to a light density of each element lens in the lens array.
[4] The stereoscopic image display device according to [3], wherein the display unit displays the integral image with larger pixels as the light density of each element lens is higher.

  According to the present invention, in integral photography, it is possible to obtain a stereoscopic image in which a deviation in definition is reduced or eliminated.

It is a figure which shows schematic structure of the stereo image imaging device and stereo image display apparatus which are one Embodiment of this invention. It is a figure which shows the arrangement | sequence of the element lens in a lens array. Each is a cross-sectional view of a pinhole array cut along a plane including one pinhole row, a diagram showing a pixel row obtained by light rays passing through the pinhole, and a distance of a perpendicular line from the pinhole to the pixel row. It is the figure which showed the pixel row | line | column obtained by the light ray which passes through a pinhole in the case of being long enough with respect to the width of a pixel. FIG. 4 is a cross-sectional view of an element lens row in a lens array cut by a plane including an optical axis for one row, a diagram showing a pixel row obtained by a light beam passing through an element lens of the lens array, and a pixel width 5 is a diagram showing a pixel row obtained by a light beam passing through an element lens when the focal length is sufficiently long. It is a figure which shows typically the outline of the pixel structure of the imaging surface which an imaging part has. It is the figure which expanded and showed the central part vicinity of the pixel area typically.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram illustrating a schematic configuration of a stereoscopic image capturing apparatus and a stereoscopic image display apparatus according to an embodiment of the present invention. The figure shows a three-dimensional image capturing device 1 that captures an object S by integral photography, which is one method of aerial image reproduction, and generates an integral image, and an integral image generated by the three-dimensional image capturing device 1. 3D shows a stereoscopic image display device 2 that generates a stereoscopic image S ′ in a space by displaying it by a photograph.

The stereoscopic image photographing device 1 is realized by a camera device capable of photographing a moving image and / or a still image, for example. The stereoscopic image capturing apparatus 1 includes a lens array 110, a lens optical system 120, an imaging unit 130, a storage unit 140, and an image supply unit 150.
However, in the configuration of the stereoscopic image capturing apparatus 1 in FIG. 1, the lens array 110, the lens optical system 120, and the imaging unit 130 are schematic cross-sectional views when viewed from the side of the stereoscopic image capturing apparatus 1. The storage unit 140 and the image supply unit 150 are blocks showing functional configurations.

  The lens array 110 is an element lens group configured by regularly arranging a plurality of element lenses on a plane (hereinafter referred to as a two-dimensional array) so that the optical axes are parallel to each other. The regularity of the two-dimensional array will be described later. Each of the plurality of element lenses constituting the lens array 110 is, for example, a convex lens that has no distortion such as barrel distortion and pincushion distortion or can be ignored. The fact that there is no distortion or is negligibly small means that the distortion is approximately 0% (including 0%) (the same applies hereinafter).

  The lens optical system 120 is a plurality of lenses that are disposed between the lens array 110 and the imaging unit 130 and condense light beams coming from the lens array 110 onto the imaging surface of the imaging unit 130. Specifically, the lens optical system 120 includes a condenser lens 21 and an objective lens 22. The condensing lens 21 is a lens that condenses light beams coming from a plurality of element lenses of the lens array 110. The objective lens 22 is a lens that collects the light flux coming from the condenser lens 21 and forms an image of this light flux on the imaging surface of the imaging unit 130. The optical axes of the condensing lens 21 and the objective lens 22 are coaxial and coincide with the optical axis O of the stereoscopic image capturing apparatus 1.

  The imaging unit 130 captures captured image data (integral image data) by imaging a light beam coming from the objective lens 22 of the lens optical system 120, that is, a light beam coming from the subject S via the lens array 110 and the lens optical system 120. ) And the captured image data is stored in the storage unit 140. The imaging unit 130 receives and images the light flux coming from the lens array 110 via the lens optical system 120 on an imaging surface having a pixel structure corresponding to the light density of each element lens in the lens array 110. Specifically, the imaging unit 130 receives a light beam coming from the lens array 110 via the lens optical system 120 on an imaging surface having a larger pixel area (larger pixel) as the light density of each element lens is higher. Take an image. As a result, the imaging unit 130 generates captured image data as integral image data in which the light density of each pixel is substantially uniform (including equality, the same applies hereinafter). The pixel structure of the imaging surface included in the imaging unit 130 will be described later.

  The imaging unit 130 is realized by a solid-state imaging device such as a CCD (Charged Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor.

The storage unit 140 stores captured image data supplied from the imaging unit 130. The storage unit 140 is realized by a semiconductor storage device, for example.
The image supply unit 150 reads captured image data stored in the storage unit 140 and supplies the captured image data to the stereoscopic image display device 2.

The stereoscopic image display device 2 is realized by, for example, a rear projection type projection device (projector). The stereoscopic image display apparatus 2 includes an image acquisition unit 210, a display unit 220, a projection lens optical system 230, a screen 250, and a lens array 240.
However, in the configuration of the stereoscopic image display device 2 in FIG. 1, the display unit 220, the projection lens optical system 230, the screen 250, and the lens array 240 are schematic cross sections when viewed from the side of the stereoscopic image display device 2. FIG. The image acquisition unit 210 is a block that indicates a functional configuration.

  The image acquisition unit 210 takes captured image data supplied from the image supply unit 150 of the stereoscopic image capturing apparatus 1 and supplies the captured image data to the display unit 220.

The display unit 220 takes captured image data supplied from the image acquisition unit 210 and displays a captured image (integral image) on the display surface of the display unit 220. The display unit 220 transmits a light beam that reaches the lens array 240 via the projection lens optical system 230 and the screen 250 from a display surface having a pixel structure corresponding to the light density of each element lens (described later) in the lens array 240. Let it emit. Specifically, the display unit 220 displays a light beam reaching the lens array 240 via the projection lens optical system 230 and the screen 250 so that the pixel area is larger (the pixel is larger) as the light density of each element lens is higher. The light is emitted from the surface. Thereby, the display unit 220 emits a light beam in which the light beam density of the light beam projected through the lens array 240 is substantially uniform (including equality, the same applies hereinafter). The pixel structure of the display surface included in the display unit 220 will be described later.
The display unit 220 is realized by a solid display element such as a liquid crystal display element.

  The projection lens optical system 230 is an optical system including a lens that enlarges the luminous flux of the integral image coming from the display surface of the display unit 220 and projects it onto the screen 250. The optical axis of the projection lens optical system 230 coincides with the optical axis O ′ of the stereoscopic image display device 2.

  The screen 250 is a diffusion plate that receives the light beam of the enlarged integral image coming from the projection lens optical system 230 on one surface and diffuses it on the other surface. Therefore, an integral image is displayed on the other surface of the screen 250, that is, the surface on the lens array 240 side.

  The lens array 240 is an element lens group in which a plurality of element lenses are regularly arranged in a two-dimensional manner so that the optical axes are parallel to each other. The regularity of the arrangement of element lenses in the lens array 240 is the same as the regularity of the arrangement of element lenses in the lens array 110. Each of the plurality of element lenses constituting the lens array 240 is, for example, a concave lens that has no distortion such as barrel distortion and pincushion distortion or can be ignored. The lens array 240 reproduces the stereoscopic image S ′ by passing a light beam from the integral image displayed on the screen 250.

  The imaging unit 130 and the display unit 220 may be a single plate type or a three-plate type of red, green, and blue. In addition, the imaging unit 130 and the display unit 220 are configured to have two systems of green, and the other green component image is shifted by 0.5 pixels in the horizontal direction, the vertical direction, or both directions with respect to one green component image. A four-plate type may be used.

2A and 2B are diagrams showing the arrangement of element lenses in the lens array 110 and the lens array 240, respectively. FIGS. 7A and 7B show a part of each of the lens array 110 and the lens array 240.
FIG. 4A shows an example in which a plurality of element lenses are arranged in a square lattice pattern. When the diameter of the element lenses is D, in a square lattice array, the pitch P _X in the X-axis direction is D ≦ P _X. The pitch P _Y in the Y-axis direction is D ≦ P _Y.
FIG. 2B shows an example in which a plurality of element lenses are arranged in a delta arrangement. In the delta arrangement, the pitch _{P X} in the X-axis direction is D / 2 ≦ _{P X.} The pitch P _Y in the Y-axis direction is (√3) D / 2 ≦ P _Y.

Next, the direction of light rays passing through the pinhole when the lens array 110 is replaced with a pinhole array will be described with geometric optics.
3A and 3B are cross-sectional views when the pinhole array is cut along a plane including one row of pinholes. FIG. 4A shows a pixel row obtained by light rays passing through a pinhole. In FIG. 2A, a pixel column 11 is a part of a pixel column obtained through a pinhole 12. X-axis direction width of each pixel in the pixel array 11 is P _e. Further, f is a perpendicular distance from the pinhole 12 to the pixel column 11. In FIG. (A), amount of angular displacement alpha ₂ for obtaining light of angular displacement alpha _1, and the pixel P ₂ for obtaining a pixel P ₁ through the pinhole 12 is represented by the following formula (1) The

  The amount of angular displacement of a light beam for obtaining a pixel through a pinhole is referred to as a sampling angle amount for that pixel. According to the equation (1), the sampling angle amount with respect to the pixel decreases as the position of the pixel moves away from the position where the perpendicular to the pixel column and the pixel column intersect from the pinhole.

FIG. 3B is a diagram showing a pixel column obtained by light rays passing through the pinhole when the perpendicular distance from the pinhole to the pixel column is sufficiently long with respect to the pixel width. In FIG. 2B, a pixel column 11a is a part of a column of pixels obtained through the pinhole 12. Width in the X-axis direction of each pixel in the pixel column 11a is very narrow with respect to the pixel width P _e in FIG. (A). If the center position of the element image of the pixel row 11a and _(C x, _{C y),} the center _{position (C} x, _{C y)} straight Z connecting the position of the pin hole 12 is perpendicular to the X axis, the pixel The center sampling angle β (P _x , P _y ) for the pixel whose center position is (P _x , P _y ) is expressed by the following equation (2).

As shown in Expression (2), since the center sampling angle β (P _x , P _y ) of the light ray is obtained by an arctangent function, the change in the center sampling angle with respect to the change in the linear position of the pixel is nonlinear. Specifically, the amount of change in the center sampling angle decreases as the distance from the center position of the element image increases. That is, the sampling interval of light rays coming from the subject via the pinhole array becomes narrower as the incident angle with respect to the pinhole is larger. The incident angle is an angle formed by incident light rays with respect to a straight line that is orthogonal to a plane including a plurality of pinholes in the pinhole array and passes through the pinholes. Therefore, the smaller the incident angle with respect to the pinhole, the lower the light density per pixel obtained by the pinhole.

  The light beam passing through the pinhole when the lens array 240 is replaced with a pinhole array is the same as in the case of the above imaging system. Therefore, the definition of the stereoscopic image observed from the direction directly facing the pinhole array is lower than the stereoscopic image observed from the direction angled with respect to the direction directly facing the pinhole array.

Next, the direction of the light beam passing through the element lenses of the lens array 110 will be described using geometric optics.
FIGS. 4A and 4B are cross-sectional views when one row of element lenses in the lens array 110 is cut by a plane including the optical axis for one row. FIG. 5A shows a pixel row obtained by a light beam that passes through the element lenses of the lens array 110. In FIG. 2A, a pixel column 11b is a part of a pixel column obtained through the element lens 13. X-axis direction width of each pixel in the pixel column 11b is P _e. Further, f is the focal length of the element lens 13. The center sampling angle is an angle formed between the optical axis of the element lens 13 and the principal ray obtained by the pixel through the element lens 13. Similar to the case where the pinhole array shown in FIG. 3A is applied, even when the lens array 110 is applied, as the pixel position is further away from the position where the optical axis of the element lens intersects the pixel column, the pixel The sampling angle amount with respect to is small.

FIG. 4B is a diagram illustrating a pixel row obtained by a light beam passing through an element lens of the lens array 110 when the focal length is sufficiently long with respect to the pixel width. In FIG. 5B, a pixel column 11c is a part of a pixel column obtained through the element lens 13. Width in the X-axis direction of each pixel in the pixel column 11c is a very narrow width to the pixel width P _e in FIG. (A). In FIG. 5B, the center sampling angle when the focal length f is approximated to be sufficiently long with respect to the width of the pixel is the optical axis Z of the element lens 13 and the principal ray obtained by the pixel through the element lens 13. Is an angle. That is, if the diameter of the element lens 13 is D and the center sampling angle is β (P _x , P _y ) as in FIG. 3B, the light flux at the center sampling angle β (P _x , P _y ) of the element lens 13. The sampling width W (P _x , P _y ) is expressed as the following equation (3). The sampling width W (P _x , P _y ) is the maximum width of a cross section obtained by cutting a light beam incident on the element lens 13 having a central sampling angle with respect to the optical axis Z by a plane orthogonal to the light beam.

As shown in Expression (3), since the sampling width W (P _x , P _y ) of the light beam is obtained by a cosine function, the change in the sampling width with respect to the change in the linear position of the pixel is nonlinear. Specifically, the amount of change in the sampling width with respect to the change in the pixel position becomes narrower as the distance from the center position of the element image increases. That is, the sampling width of the light beam coming from the subject via the lens array 110 becomes narrower as the incident angle with respect to the element lens becomes larger. In other words, the sampling density (light beam density) increases as the sampling width of the light beam coming from the subject via the lens array 110 becomes narrower. Therefore, the smaller the incident angle with respect to the element lens, the lower the spatial frequency of information obtained by the element lens.

  The light beam passing through the element lens of the lens array 240 is the same as in the case of the above-described photographing system. Therefore, the definition of the stereoscopic image observed from the direction facing the lens array 240 is lower than the stereoscopic image observed from the direction at an angle with respect to the direction facing the lens array 240.

  As described above, regardless of which of the pinhole array and the lens array 110 is applied, the sampling density (ray density) of light rays coming from the subject decreases as the incident angle decreases. In addition, regardless of which of the pinhole array and the lens array 240 is applied, the sampling density of the light rays emitted from the lens array 240 becomes lower as the emission angle becomes smaller. The emission angle is an angle formed by the outgoing light beam with respect to the optical axis.

Next, the pixel structure of the imaging surface included in the imaging unit 130 will be described.
FIGS. 5A and 5B are diagrams schematically illustrating an outline of a pixel structure of an imaging surface included in the imaging unit 130. FIG. FIGS. 5A and 5B also show a part of the imaging surface.
FIG. 4A is a schematic diagram of the pixel structure of the imaging surface of the imaging unit 130 when the arrangement of the element lenses in the lens array 110 is a square lattice arrangement. In FIG. 6A, the imaging surface represented by the XY plane includes a plurality of pixel regions (pixel region group) arranged in a square lattice pattern corresponding to the plurality of element lenses included in the lens array 110. Is done. A pixel region E, which is one of the plurality of pixel regions, is a pixel region in a range that does not include a light beam obtained by an element lens adjacent to the element lens among light beams obtained by a corresponding element lens by geometric optics. is there.
A pixel area E in FIG. 2A is, for example, substantially circular.

FIG. 5B is a schematic diagram of the pixel structure of the imaging surface of the imaging unit 130 in the case where the arrangement of the element lenses in the lens array 110 is a delta arrangement. In FIG. 5B, the imaging surface represented by the XY plane is configured to include a plurality of pixel regions (pixel region group) arranged in a delta shape corresponding to the plurality of element lenses included in the lens array 110. The A pixel area E, which is one of the plurality of pixel areas, has a luminous flux obtained by an element lens adjacent to the element lens among luminous fluxes obtained by the corresponding element lens by geometric optics, as in FIG. This is a pixel area in a range that does not include.
A pixel region E in FIG. 4B is, for example, a substantially circular shape.

FIG. 6 is an enlarged view schematically showing the vicinity of the center of the pixel region E in FIGS. 5 (a) and 5 (b). As shown in the figure, the pixel region E has, for example, a plurality of pixels divided concentrically and circumferentially with respect to the center of the region. That is, the pixel structure of the pixel region E is a structure in which the area of the pixel increases in the radial direction from the center of the pixel region E. Specifically, as the pixel region E is further away from the center in the radial direction, the radius of the concentric circle, that is, the width of the ring increases nonlinearly, and is divided at an equal angle (11.25 degrees in the figure) in the circumferential direction. A plurality of pixels. The degree of change in the radius of the concentric circle with respect to the center of the pixel region E is determined based on, for example, the position (P _x , P _y ) of the center of the pixel in the above-described equation (2).
Thereby, the imaging unit 130 can receive and image the light flux obtained from the element lens group of the lens array 110 on the imaging surface with a larger pixel area (larger pixel) as the light density is higher.

The pixel structure of the display surface included in the display unit 220 is the same as the pixel structure of the imaging surface included in the imaging unit 130 described above. That is, the display surface included in the display unit 220 also has a pixel structure similar to the pixel structure of the imaging surface included in the imaging unit 130 illustrated in FIGS. Specifically, similar to the pixel area E of the display surface illustrated in FIG. 6, the pixel area on the display surface included in the display unit 220 is, for example, a plurality of concentric and circumferential segments with respect to the center of the area. Of pixels. That is, the pixel structure of the pixel region is a structure in which the area of the pixel increases in the radial direction from the center of the pixel region. Specifically, the pixel region has a plurality of pixels that are concentrically divided in the circumferential direction and the radius of the concentric circle, that is, the width of the ring increases nonlinearly as the distance from the center in the radial direction increases. The degree of change in the radius of the concentric circle with respect to the center of the pixel region is determined based on, for example, the position (P _x , P _y ) of the center of the pixel in Expression (2) described above.
Thereby, the display unit 220 can emit a light beam in which the light beam density projected through the lens array 240 is substantially uniform.

As described above, the stereoscopic image capturing apparatus 1 according to the embodiment of the present invention is configured to arrange the lens array 110 configured by two-dimensionally arranging a plurality of element lenses, and the luminous flux obtained through the lens array 110 in each lens array 110. An imaging unit 130 that receives and captures an image on an imaging surface having a pixel structure corresponding to the light density of the element lens, and generates integral image data that is a set of element images corresponding to each of the plurality of element lenses included in the lens array 110. And with. For example, the imaging unit 130 receives and images the light beam obtained through the lens array 110 on an imaging surface with larger pixels as the light density of each element lens in the lens array 110 is higher.
According to this configuration, the imaging unit 130 receives and captures the light flux obtained from the element lens group of the lens array 110 on the imaging surface having a larger pixel area (larger pixel) as the light density of each element lens is higher. . Thereby, the imaging unit 130 can obtain integral image data in which the deviation of the light density is reduced or eliminated. Therefore, according to the three-dimensional image photographing device 1, it is possible to reduce or eliminate the deviation in definition.

  Further, the smaller the sampling angle amount, the higher the definition of the depth direction of the subject. Therefore, according to the three-dimensional image photographing device 1, it is possible to acquire an integral image with high definition in the depth direction in the subject in the front direction with respect to the own device.

In addition, the stereoscopic image display device 2 according to an embodiment of the present invention includes a lens array 240 configured by two-dimensionally arranging a plurality of element lenses, and an integral image that is a set of a plurality of element images having parallax with each other. A display unit 220 that displays data on a display surface having a pixel structure corresponding to the light density of each element lens in the lens array 240 is provided. For example, the display unit 220 displays the integral image data with larger pixels as the light density of each element lens in the lens array 240 is higher.
According to this configuration, the display unit 220 can emit a light beam in which the light beam density projected through the lens array 240 is substantially uniform. Therefore, according to the stereoscopic image display device 2, it is possible to obtain a stereoscopic image in which the deviation in definition is reduced or eliminated.

  Also, the smaller the sampling angle amount, the higher the resolution in the depth direction of the stereoscopic image. Therefore, according to the stereoscopic image display device 2, when the viewpoint is set in the front direction with respect to the own device, a stereoscopic image having a high resolution in the depth direction can be obtained.

  Also, in the element image obtained by the light flux that has passed through the element lens, the circle of confusion increases as the distance from the point through which the optical axis of the element lens penetrates, and the chromatic aberration deteriorates. However, according to the present embodiment, since the pixels are increased toward the outside from the center position of the element image, the permissible circle of confusion can be increased in the peripheral portion where the light collecting performance is inferior to the center portion, and The influence of optical deterioration such as chromatic aberration can be suppressed.

In the present embodiment, an example in which a convex lens is used as the element lens of the lens array 110 and a concave lens is used as the element lens of the lens array 240 is shown.
In addition, a concave lens may be used as the element lens of the lens array 110, and a convex lens may be used as the element lens of the lens array 240.

  Moreover, in this embodiment, the example which applied the three-dimensional image display apparatus 2 to the projection apparatus was demonstrated. In addition, the stereoscopic image display device 2 can be applied to a direct view display. In this case, the stereoscopic image display device 2 is configured without using the projection lens optical system 230.

  In addition, crosstalk occurs in a lens array using a convex lens or a concave lens as an element lens of the photographing system and the display system. Accordingly, a gradient index lens (GRIN) lens may be applied to any of the element lenses of the lens array 110 and the lens array 240. By making the element lens a gradient index lens, crosstalk between element images can be eliminated. Further, by using a gradient index lens, it is possible to obtain a high-definition three-dimensional image that is substantially free from crosstalk.

  As a gradient index lens, a lens having the following specifications is used. That is, when the length of the gradient index lens in the optical axis direction is Z and the meandering period of the gradient index lens is P, a gradient index lens satisfying the relationship P / 2 <Z <P is obtained. The present invention is applied to element lenses of the lens array 110 and the lens array 240. By using this gradient index lens, the lens array 110 and the lens array 240 have a principal point outside the lens, and an erect real image can be obtained.

  When a gradient index lens with Z = 3P / 4 (0.75 pitch) is used, an erect real image of the subject S located sufficiently far from one end face of the gradient index lens is placed on the other end face. You can make it appear. By using the lens array 110 and the lens array 240 to which this 0.75 pitch gradient index lens is applied, crosstalk between adjacent element lenses can be prevented.

  Note that a refractive index distribution type lens satisfying a relationship of P / 2 + (n−1) P <Z <nP (n is an integer of 2 or more) may be applied as the refractive index distribution type lens. Alternatively, a gradient index lens in which Z = 3P / 4 + (n−1) P (n is an integer of 2 or more) may be applied.

Also, the pixel region E shown in FIGS. 5A, 5B, and 6 may be a rectangular (for example, square) region. In this case, for example, the rectangular pixel region E having a center point that coincides with the center of the element image has a plurality of pixels divided in the horizontal direction and the vertical direction with respect to the center. That is, the pixel structure of the rectangular pixel region E is a structure in which the size of the pixel becomes longer in the horizontal direction and in the vertical direction from the center of the pixel region E. Specifically, the pixel region E has a plurality of pixels in which the side length of the block increases nonlinearly as the distance from the center in the horizontal direction and the vertical direction increases. The degree of change in the side length of the block with respect to the center of the pixel region E is determined based on, for example, the position (P _x , P _y ) of the center of the pixel in Expression (2) described above.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to that embodiment, The design of the range which does not deviate from the summary of this invention, etc. are included.

DESCRIPTION OF SYMBOLS 1 Stereoscopic image imaging device 2 Stereoscopic image display device 3 Image processing device 21 Condensing lens 22 Objective lens 110 Lens array 120 Lens optical system 130 Imaging part 140 Storage part 150 Image supply part 210 Image acquisition part 220 Display part 230 Projection lens optical system 240 lens array 250 screen

Claims (4)

A lens array configured by two-dimensionally arranging a plurality of element lenses;
It is a set of element images corresponding to each of the plurality of element lenses, in which a light beam obtained through the lens array is received and imaged by an imaging surface having a pixel structure corresponding to the light density of each element lens in the lens array. An imaging unit for generating an integral image;
A stereoscopic image photographing apparatus comprising: The stereoscopic image capturing apparatus according to claim 1, wherein the imaging unit receives and captures the light flux on an imaging surface with larger pixels as the light density of each element lens is higher. In a stereoscopic image display device including a lens array configured by two-dimensionally arranging a plurality of element lenses,
A three-dimensional display comprising: a display unit configured to display an integral image, which is a set of a plurality of element images having parallax with each other, on a display surface having a pixel structure corresponding to the light density of each element lens in the lens array. Image display device. The stereoscopic image display device according to claim 3, wherein the display unit displays the integral image with larger pixels as the light density of each element lens is higher.

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