JP2018007110A - Display device and screen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in which conventional projection devices cause chromatic aberration in stereoscopic images.SOLUTION: A display device includes: a display unit for displaying photographed data obtained by a plurality of light-receiving units arranged for each group of a plurality of lenses arranged two-dimensionally photographing light that has passed through a photographing optical system; and a projection unit for projecting the image which is displayed on the display unit and which the light-receiving units arranged for each group of the lenses have received for each group of a plurality of concave mirrors arranged two-dimensionally.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a display device and a screen.

  A projection apparatus that displays a stereoscopic image by projecting an image on a screen is known (see, for example, Patent Document 1). The conventional projection apparatus has a problem that chromatic aberration occurs in a stereoscopic image.

JP 2009-216752 A

According to the first aspect, the display device includes a display unit that displays imaging data obtained by imaging light transmitted through the imaging optical system with a plurality of light receiving units arranged for each of a plurality of lenses arranged in a two-dimensional manner, A projection unit that projects images received by a plurality of light receiving units arranged for each of the plurality of lenses displayed on the display unit to a plurality of concave mirrors arranged in a two-dimensional manner.
According to the second aspect, the screen includes a projection surface and a plurality of concave mirrors provided on the projection surface and arranged two-dimensionally.

The figure which shows the structure of a three-dimensional display apparatus typically. A diagram schematically showing the arrangement of multiple concave mirrors Diagram showing the configuration of the projector Sectional drawing which showed typically the image sensor which a light field camera has Figure illustrating a light field image The figure which shows the modification of the shape and arrangement | sequence of a concave mirror The figure which shows the modification of the arrangement of a concave mirror The figure which shows the modification of a stereoscopic display device

(First embodiment)
FIG. 1 is a diagram schematically illustrating the configuration of the display device according to the first embodiment. The stereoscopic display device (display device) 1 includes a projector 11 and a projection screen (screen) 12. The projector 11 is a liquid crystal projector, for example, and projects a two-dimensional image, which will be described later, toward the projection screen 12.

  The projection screen 12 has a plurality of concave mirrors 121 on the projection surface. The plurality of concave mirrors 121 are two-dimensionally arranged on one surface of the projection screen 12. The plurality of concave mirrors 121 are arranged so that the concave surfaces face the direction of the projector 11. The plurality of concave mirrors 121 are arranged so as to form the plane 3 as a whole. The projector 11 projects a two-dimensional image toward the concave surfaces of the plurality of concave mirrors 121.

  The projector 11 forms a two-dimensional image on a predetermined projection image plane 2. The projection image plane 2 is located near the focal plane of the plurality of concave mirrors 121. That is, the projection image plane 2 is set at a position away from the main plane of the plurality of concave mirrors 121 by the focal length f of the plurality of concave mirrors 121 (in the direction of the projector 11).

  2A is a plan view schematically showing the arrangement of the plurality of concave mirrors 121, and FIG. 2B is a cross-sectional view schematically showing the arrangement of the plurality of concave mirrors 121. As shown in FIG. Each concave mirror 121 has a circular contour shape (opening shape). The plurality of concave mirrors 121 are squarely arranged in a two-dimensional shape.

  FIG. 3 is a diagram schematically showing the configuration of the projector 11. The projector 11 includes a control unit 110, a storage unit 111, a projection lens 112, a light source unit 113, and a projection unit 114.

  The control unit 110 has a CPU (not shown) and its peripheral circuits. The control unit 110 controls the projector 11 as a whole by reading and executing a predetermined control program from a storage medium (not shown). The storage unit 111 is a portable storage medium such as a memory card. The storage unit 111 stores one or more image data.

  The control unit 110 reads the image data from the storage unit 111 and outputs the image data to the projection unit 114. The light source unit 113 is a light source such as an LED. Light from the light source unit 113 enters the projection unit 114. The projection unit 114 includes, for example, a liquid crystal panel, a micromirror device, and the like, and projects a two-dimensional image based on the image data input by the control unit 110 onto the projection lens 112 that is a projection unit using light from the light source unit 113. . The projection lens 112 projects a two-dimensional image based on the image data read by the control unit 110 toward the projection screen 12. The projection lens 112 has an F value that is greater than twice the F value of the concave mirror 121. This point will be described in detail later.

  Note that the projector 11 may acquire image data from a location different from the storage unit 111. For example, image data may be input from the outside of the projector 11 through a predetermined interface.

  The two-dimensional image projected by the projector 11 is a light field image captured by a light field camera. When the observer observes the projection screen 12 on which the light field image is projected by the projector 11, a stereoscopic image based on the light field image is observed. That is, the projection screen 12 reproduces a stereoscopic image based on the light field image.

  Hereinafter, a light field camera that captures a light field image and a playback apparatus that can play back the light field image will be described in order. Thereafter, the projection screen 12 will be described.

  FIG. 4 is a cross-sectional view schematically showing the image sensor 50 included in the light field camera. The image sensor 50 includes a microlens array 51 and a light receiving element array 52. The microlens array 51 has a plurality of microlenses 53 that are two-dimensionally arranged squarely. The light receiving element array 52 includes a plurality of light receiving elements 54 arranged in a two-dimensional square shape. A plurality of light receiving elements 54 correspond to one microlens 53. That is, the number of light receiving elements 54 is larger than the number of microlenses 53. In FIG. 4, for the sake of convenience, only a part of the microlens 53 and the light receiving element 54 are shown larger than the actual size.

  The light receiving surface of the light receiving element array 52 is provided near the focal plane 57 of the plurality of microlenses 53. The subject light that has passed through the imaging optical system 55 of the light field camera passes through the plurality of microlenses 53 and enters the plurality of light receiving elements 54. The microlens array 51 is disposed in the vicinity of the planned focal plane 56 of the imaging optical system 55. Note that the F value of the microlens 53 is preferably the same as the F value of the imaging optical system 55.

  The subject image formed in the vicinity of the microlens array 51 by the imaging optical system 55 is compressed in the depth direction by the plurality of microlenses 53 provided in the microlens array 51 and is folded into the light receiving element array 52. For example, when the image magnification of the imaging optical system 55 is 1/50, that is, when the imaging optical system 55 forms an object image on the planned focal plane 56 with an actual size of 1/50, the object is viewed in the depth direction. The image is formed at a magnification of 1/2500, which is the square of the image. That is, the imaging optical system 55 forms a stereoscopic image obtained by compressing the subject in the three-dimensional space in the depth direction on the planned focal plane 56.

  A two-dimensional image that is image data captured by the image sensor 50 configured as described above is a light field image. The light field image is an image that looks different from an image captured by a normal camera due to the action of the microlens array 51.

  FIG. 5A is a diagram illustrating a light field image obtained by imaging the character “A” shown in FIG. As shown in FIG. 5A, the light field image is an image that looks much different from the original subject.

  When a light field image captured by a light field camera is displayed on a display device having the same configuration as that of the image sensor 50, a stereoscopic image can be observed. Specifically, a display device is prepared in which the light receiving element array 52 of the imaging element 50 illustrated in FIG. 4 is replaced with a display pixel array (for example, a liquid crystal panel) having a plurality of display pixels. If the light field image is displayed by the display pixel array, the display light emitted from each display pixel passes through the microlens array 51 in the direction opposite to that at the time of imaging and travels toward the observer. As a result, the observer can observe the base stereoscopic image.

  Note that if the light field image is displayed as it is on the display pixel array, the depth of the stereoscopic image to be observed is reversed from the underlying subject image. Therefore, it is desirable to pre-process the light field image so that the depth direction is reversed. For example, the control unit 110 performs preprocessing for rotating (inverting) the image in the minute area 60 by 180 degrees for each minute area 60 constituting the light field image. Alternatively, image data that has been subjected to such preprocessing in advance is stored in the storage unit 111. By doing so, it is possible to reproduce a stereoscopic image observed from the observer in the correct direction. Here, the micro area 60 is an area covered by one micro lens 53. That is, each micro area 60 corresponds to one micro lens 53.

  The plurality of concave mirrors 121 in the projection screen 12 function in the same manner as the plurality of microlenses 53 in the display device described above except that they are of a reflective type. That is, in the display device described above, similarly to the case where the display light from the display pixels is directed to the observer through the plurality of microlenses 53, the projection light from the projector 11 is transmitted through the plurality of concave mirrors 121 (the plurality of concave mirrors). (Reflected by 121) toward the viewer. As described above, the projection screen 12 forms a three-dimensional light field image on the projection image plane 2 and allows the observer to observe the three-dimensional light field image.

  For example, assuming that the horizontal resolution of the projector 11 is 4096 and the horizontal width of the projection screen 12 is 2 m, one pixel of the projected light field image has a size of 0.49 mm. If the diameter of the concave mirror 121 is 4.9 mm, the focal length is 50 mm, and the radius of curvature is 100 mm, the F-number of the concave mirror 121 is 10, and the sag amount (that is, the central dent amount from the periphery) is 31 μm. When the F value of the projection lens 112 of the projector 11 is 3, the light beam formed on the projection image plane 2 spreads from one point of the projection image plane 2 to about 3.3 concave mirrors 121 (F value / value of the concave mirror 121 / F value of the projection lens 112). At this time, the product of the focal length of the concave mirror 121 and the diameter (pixel unit) of the concave mirror 121 is a reproducible depth. Since the focal length of the concave mirror 121 is 50 mm, the diameter of the concave mirror 121 is 4.9 mm, and one pixel is 0.49 mm in size, the diameter of the concave mirror 121 in units of pixels is 10, and thus the reproducible depth is 500 mm. That is, it is possible to reproduce a stereoscopic image having a depth of 500 mm before and after the projection screen 12.

If the F value of the projection lens 112 of the projector 11 is larger than twice the F value of the concave mirror 121, the alignment of the minute region 60 of the light field image projected by the projector 11 and the concave mirror 121 is unnecessary. .
5A is a light field image obtained by imaging the character “A” shown in FIG. 5B, the image data of the character “A” created by computer graphics is used. May be processed by a known signal processing method to generate light field image data corresponding to the character “A”, and the generated image may be displayed on the display device and projected as described above. .

According to the embodiment described above, the following operational effects can be obtained.
(1) The projection screen 12 includes a plurality of concave mirrors 121 arranged two-dimensionally. When the light field image picked up by the light field camera is projected onto the projection screen 12, the projection screen 12 forms a three-dimensional light field image on the predetermined projection image plane 2. Since it did in this way, a chromatic aberration does not arise in a screen but a high-quality three-dimensional image can be observed.

(2) The plurality of concave mirrors 121 are arranged so as to form the plane 3 as a whole. Since it did in this way, manufacture of the projection screen 12 becomes easy.

(3) The stereoscopic display device 1 includes the projection screen 12 and the projector 11 that projects a light field image toward the reflecting surfaces of the plurality of concave mirrors 121. Since it did in this way, a chromatic aberration does not arise in a screen but a high-quality three-dimensional image can be observed.

(4) The projector 11 projects the light field image obtained by inverting the image in the micro area 60 by 180 degrees for each of the micro areas 60 corresponding to the micro lenses 53 included in the light field camera. Since it did in this way, an observer can observe a solid image with the correct direction of the depth direction.

(5) The projector 11 forms a light field image on the projection image plane 2 provided at a position closer to the projector 11 than the reflecting surface of the concave mirror 121. More specifically, the projector 11 forms a light field image on the projection image plane 2 at a position separated from the reflecting surface of the concave mirror 121 by the focal length of the plurality of concave mirrors 121 on the projector 11 side. Since it did in this way, a high-quality three-dimensional image can be observed.

(7) The projector 11 projects a light field image via the projection lens 112 having an F value larger than twice the F value of the concave mirror 121. Since it did in this way, alignment with the micro field 60 of the light field image projected by projector 11 and concave mirror 121 becomes unnecessary.

(Modification 1)
The concave mirror 121 does not have to be circular, and the arrangement thereof does not have to be a square arrangement. For example, as shown in FIG. 6, the concave mirrors 121 having a hexagonal outer shape (opening shape) may be densely arranged (so-called honeycomb arrangement).

(Modification 2)
As illustrated in FIG. 7, the concave mirrors 121 may be arranged so that the plurality of concave mirrors 121 form a concave surface 70 as a whole. By doing so, the appearance of the stereoscopic image especially in the vicinity of the end of the projection screen 12 is improved.

(Modification 3)
As illustrated in FIG. 8, a field lens 80 may be provided around the projection image plane 2. By doing so, the appearance of the stereoscopic image especially in the vicinity of the end of the projection screen 12 is improved.

DESCRIPTION OF SYMBOLS 1 ... Stereoscopic display apparatus, 11 ... Projector, 12 ... Projection screen, 121 ... Concave mirror

Claims (15)

A display unit for displaying imaging data obtained by imaging light transmitted through the imaging optical system by a plurality of light receiving units arranged for each of a plurality of lenses arranged two-dimensionally;
A projection unit for projecting an image received by a plurality of light receiving units arranged for each of the plurality of lenses displayed on the display unit to a plurality of concave mirrors arranged two-dimensionally;
A display device comprising: The display device according to claim 1,
The projection unit is a display device that forms the image at a position closer to the projection unit than a reflection surface of the concave mirror. The display device according to claim 2,
The projection unit forms the image with a projection lens,
The projection lens is a display device that forms the image at a position substantially away from the reflecting surface of the concave mirror at a substantially focal length of the projection lens on the projection unit side. The display device according to claim 2 or claim 3,
The projection unit forms the image with a projection lens,
The display device wherein the F value of the projection lens is twice or more the F value of the concave mirror. In the display device according to any one of claims 2 to 4,
The projection unit forms the image with a projection lens,
A display device comprising a field lens between the projection lens and the plurality of concave mirrors. In the display device according to any one of claims 1 to 5,
The plurality of concave mirrors are display devices provided on a projection surface having a flat shape. In the display device according to any one of claims 1 to 5,
The plurality of concave mirrors is a display device provided on a projection surface having at least a part of a curved surface. The display device according to claim 7,
The display device, wherein the curved surface is a concave surface. In the display device according to any one of claims 1 to 8,
A display device comprising a control unit that controls the display unit to display data obtained by rotating the imaging data for each lens by 180 degrees with respect to the optical axis of the lens. In the display device according to any one of claims 1 to 8,
For each of a plurality of lenses arranged in a two-dimensional manner, image data of a subject image generated by data processing instead of an image by light from a subject that has passed through a photographing optical system picked up by the plurality of light receiving units. A display device that displays, on the display unit, data converted by image processing into data corresponding to imaging data obtained by imaging light from the subject that has passed through the imaging optical system with a plurality of light receiving units. In the display device according to any one of claims 1 to 10,
A display device comprising a screen having a projection surface provided with a plurality of concave mirrors arranged two-dimensionally. A projection plane;
A plurality of concave mirrors arranged in a two-dimensional shape provided on the projection surface;
With screen. The screen of claim 12,
The projection surface has a plane shape. The screen of claim 13.
The projection surface has a shape in which at least a part is a curved surface. The screen of claim 14,
The screen is a concave surface.

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