JPH0545749A - 3D image recorder - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention is characterized by being able to record a three-dimensional image at high speed and at the same time being capable of downsizing the apparatus. According to the present invention, an object lens from a subject is incident and an image forming lens for forming an image of the object at an image forming position, and an image pickup device arranged at or near the image forming position of the image forming lens. And a spatial modulation element that is disposed between the imaging lens and the image sensor and that has a light-transmitting portion that transmits only part of the object light from the subject and that is freely movable in its position. Is characterized by.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for recording a three-dimensional image, and more particularly to a three-dimensional image recording apparatus capable of recording a three-dimensional image at high speed and reducing the size of the apparatus. It is a thing.

[0002]

2. Description of the Related Art Conventionally, in the field of three-dimensional image display, a method using a hologram or a lenticular sheet has been mainly used as a three-dimensional image without glasses. In recent years, either of these methods directly visualizes three-dimensional information in a computer or the like without displaying a moving image called a three-dimensional television or photographing an existing object called a three-dimensional printer. Methods have been announced.

Hereinafter, these methods will be briefly described.

(A) Stereoscopic television using hologram This was announced in January 1990 by Professor Benton of MIT at SPIE in the United States.
Modulate using M (acousto-optic modulator) to create a minute hologram in real time, and use that hologram with a polygon mirror or galvano mirror (both can change the direction of light by moving the mirror) It is a method of creating a three-dimensional image by hologram by arranging it in a two-dimensional space.

(B) Stereoscopic Television with Lenticular Sheets As described by Mr. Motoki of NHK in January 1991, Journal of the Photographic Society of Japan, Vol. 54, No. 1, "Stereoscopic Television," lenticular sheets and liquid crystal panels. Various methods have been proposed in various ways, in which three-dimensional moving images are created by driving the display elements such as a liquid crystal panel in real time by utilizing the characteristics of the lens of the lenticular sheet.

(C) Three-dimensional printer using hologram In 1990, SPI was written by Mr. Yamaguchi of Tokyo Institute of Technology.
It was announced at E and is a three-dimensional display using a Lippmann hologram composed of a collection of holograms in the unit of minute dots, which is formed by condensing a pattern modulated by a liquid crystal panel with a lens. This method can directly make a hard copy of three-dimensional information on a computer, like a printer or plotter for two-dimensional images.

(D) Three-dimensional printer using lenticular sheet As disclosed in "Three-dimensional plotter using integral photography" reported by Victor Iwahara at 3D Forum in June 1991, It is a method of creating a three-dimensional display by moving a point light source and multiple-exposing a photosensitive material through a lenticular sheet. With this method, a hard copy of the three-dimensional information on the computer can be directly created, as in the previous hologram method.

As described above, recently, in the field of three-dimensional image display, holograms and stereo images using lenticular sheets have been put into practical use. In these fields, methods have recently been developed for creating a moving image such as a so-called three-dimensional television or a variable image, rather than a fixed image such as a printed matter.

These methods are generally used to represent a fictitious three-dimensional image created on a computer, but in order to display a three-dimensional image from an original image obtained by photographing a real object or the like. It is necessary to record the three-dimensional information of the subject by some method.

As a conventional method for obtaining a parallax image used as an original image of a stereoscopic display using a holographic stereogram or a lenticular sheet, for example, as shown in FIG. A method of obtaining a plurality of parallax images by horizontally moving the object 3 or placing the subject 1 on a rotary stage 4 and shooting the subject 1 while rotating the subject 1 as shown in FIG. There is a method of obtaining a plurality of parallax images, etc.

However, in all of these methods, since there is a driving part in photographing, it is not possible to record a three-dimensional image at a high speed, and the apparatus becomes large accordingly. Further, particularly in the method shown in FIG. 3, since it is necessary to place the subject 1 on the rotary stage 4, the size, weight, and instability (gas, liquid, etc.) of the subject 1 to be the target should be placed on the rotary stage 4. Can not be placed) restrictions occur.

[0012]

As described above, in the conventional method, not only the three-dimensional image cannot be recorded at high speed, but also the apparatus becomes large in size.

The present invention has been made to solve the above problems, and an object thereof is to be able to record a three-dimensional image at high speed and to downsize the apparatus. It is to provide an extremely reliable three-dimensional image recording device.

[0014]

In order to achieve the above object, first, in a three-dimensional image recording apparatus according to the invention as set forth in claim 1, object light from a subject is incident and the subject is incident on an image forming position. An image forming lens for forming an image, an image pickup element provided at an image forming position of the image forming lens or a position near the image forming lens, and an object light from an object provided between the image forming lens and the image pickup element. And a spatial light modulator having a light transmitting portion that transmits only a part of the light and the position of which is freely movable.

Further, in the three-dimensional image recording apparatus of the invention described in claim 4, the object light from the subject is incident, the concave mirror for reflecting the incident light and the reflected light from the concave mirror are incident, and the image forming position is formed. An imaging lens that forms an image of the subject on the
An image pickup device disposed at the image forming position of the image forming lens or a position in the vicinity thereof, and arranged between the image forming lens and the image pickup device,
The spatial light modulator has a light transmitting portion that transmits only part of the object light from the subject and is freely movable in its position.

In particular, a liquid crystal panel is used as the spatial modulation element. Further, the spatial modulation element is arranged at the focal position of the imaging lens or in the vicinity thereof. Further, the image forming position is arbitrarily changed by changing the angle of the concave mirror according to the position of the subject.

[0017]

Therefore, in the three-dimensional image recording apparatus of the present invention, a part of the spatial modulation element is used as a light transmitting portion and the other part is used as a light non-transmissive portion, so that the object light from the object can be changed. The light transmissive portion is used as a slit, and only the light transmitted through that portion is imaged. Therefore, the direction of light is determined for each pixel of the image sensor. And
The intensity of each direction of light can be recorded by measuring the intensity of light of each pixel of the image sensor while arbitrarily moving the position of the light transmitting portion of the spatial modulation element little by little.

Further, in the three-dimensional image recording apparatus of the fourth aspect of the present invention, by disposing the concave mirror in front of the imaging lens, the imaging lens can be downsized and the cost can be reduced. be able to.

[0019]

First, the concept of the present invention will be described.

Generally, in a television camera, the image pickup element records only the intensity of light, so that only two-dimensional information can be recorded. On the other hand, in the hologram, since the light intensity and the phase information are recorded, it is possible to display a stereoscopic image. However, in a stereogram synthesized from a plurality of parallax images, light phase information is not necessary, and a stereoscopic image can be displayed only with information on light intensity and direction. Therefore, the present invention proposes an apparatus for recording the intensity and direction of light.

An embodiment of the present invention based on the above concept will be described below in detail with reference to the drawings.

FIG. 1 is a schematic diagram showing an example of the overall configuration of a three-dimensional image recording apparatus according to the present invention. That is, as shown in FIG. 1, the three-dimensional image recording apparatus according to the present embodiment has the object 1
1. An image forming lens 13 that forms an image 12 of an object 11 at an image forming position upon receiving the object light from the image forming device 1, an image pickup element 14 arranged at the image forming position of the image forming lens 13, and an image forming lens 13
And the image pickup device 14, and includes a spatial light modulator 15 which has a light transmitting portion 15a which transmits only part of the object light from the subject 11 and whose position is freely movable. There is.

Here, as the imaging lens 13, the viewing area is limited by the size of the pupil of the imaging lens 13,
As for the size of the pupil of the imaging lens 13 (the range d in which light effectively acts), a lens having a size corresponding to a necessary viewing area is used.

On the other hand, as the spatial modulation element 15, for example, a liquid crystal panel composed of an assembly of a plurality of liquid crystal units is used, and as the light transmitting portion 15a, an electric field is applied to the liquid crystal unit in that portion. The light-transmitting portion 15a is moved by sequentially shifting the liquid crystal unit to which the electric field is applied (the light is transmitted by applying the electric field). In addition, the transparent portion 1 of the spatial modulation element 15
The shape of 5a may be, for example, an elongated slit shape as shown in FIG. Furthermore, it is preferable that the size of the light transmitting portion 15a of the spatial light modulator 15 is set to a size that does not cause an influence due to the diffraction of light.

Next, the operation of the three-dimensional image recording apparatus of this embodiment constructed as described above will be described.

In FIG. 1, the image 12 of the subject 11 formed by the image forming lens 13 is formed on the image pickup device 14.
In this case, in this embodiment, the imaging lens 13 and the image sensor 1
The spatial modulation element 15 is disposed between the optical modulator 4 and the optical modulator 4. And
By applying an electric field to the liquid crystal unit of a part of the spatial modulation element 15 to form the transparent portion 15a and the other part to be a non-transparent portion, the object light from the subject 11 can be transmitted through the spatial modulation element 15a.
The light transmitting portion 15a is used as a slit, and only the light transmitted through the portion is imaged. Therefore, the direction of light is determined for each pixel of the image sensor 14. Therefore, the light intensity of each pixel of the image pickup device 14 is measured while sequentially shifting the liquid crystal unit to which the electric field is applied and gradually moving the position of the light transmitting portion 15a of the spatial light modulator 15. The intensity of each direction of light can be recorded.

As described above, in the three-dimensional image recording apparatus of this embodiment, the image forming lens 13 which receives the object light from the object 11 and forms the image 12 of the object 11 at the image forming position.
And the image pickup device 1 arranged at the image forming position of the image forming lens 13.
4, a liquid crystal panel disposed between the imaging lens 13 and the image sensor 14, which transmits only part of the object light from the subject 11 and has a light transmitting portion 15a whose position is movable. It is configured to include the spatial modulation element 15.

Therefore, since there is no driving portion for photographing as in the conventional case, the three-dimensional image can be recorded at high speed, and the possibility of recording the three-dimensional image in real time can be obtained. In addition, it is possible to reduce the size of the entire apparatus because there is no driving portion for photographing.
Further, since it is not necessary to place the subject 11 on the rotary stage as in the conventional case, the subject 11 to be targeted is not restricted as in the conventional case.

Next, another embodiment of the present invention will be described with reference to the drawings.

FIG. 3 is a schematic diagram showing another structural example of the three-dimensional image recording apparatus according to the present invention.

That is, in the three-dimensional image recording apparatus of the present embodiment, as shown in FIG. 3, the concave mirror 22 and the concave mirror 22 which are made incident by the object light from the subject 21 and reflect the incident light.
An image forming lens 24 which receives the reflected light from the image forming element 2 and forms an image 23 of the subject 21 at the image forming position, an image pickup element 25 arranged at the image forming position of the image forming lens 24, and the image forming lens 24.
And a spatial light modulator 26 which is disposed between the image pickup device 25 and a part of the object light from the subject 21 and has a transparent portion 26a whose position is freely movable. There is.

Here, the spatial modulation element 26 is constituted by a liquid crystal panel composed of an assembly of a plurality of liquid crystal units as described above, and the light transmitting portion 26a is formed by the liquid crystal in that portion. An electric field is applied to the unit (light is transmitted by the application of the electric field), and the liquid crystal units to which the electric field is applied are sequentially transferred, whereby the translucent portion 26
I am trying to move a. In addition, the spatial modulator 26
The light-transmitting portion 26a may also have an elongated slit shape, as described above. Further, it is preferable that the size of the light transmitting portion 26a of the spatial modulation element 26 is set to a size that does not cause the influence of light diffraction.

Next, the operation of the three-dimensional image recording apparatus of this embodiment constructed as described above will be described.

In FIG. 1, the object light from the subject 21 is reflected by the concave mirror 22, and the image 23 of the subject 21 formed by the imaging lens 24 is formed on the image pickup device 25.
In this case, in this embodiment, the imaging lens 24 and the image sensor 2
The spatial modulation element 26 is arranged between the optical modulator 5 and the optical modulator 5. And
By applying an electric field to the liquid crystal unit of a part of the spatial modulation element 26 to form the transparent portion 26a and the other part of the spatial modulation element 26 to be a non-transparent portion, the object light from the subject 21 is converted into the spatial modulation element 26.
The light transmitting portion 26a is used as a slit, and only the light transmitted through that portion is imaged. Therefore, the direction of light is determined for each pixel of the image sensor 25. Therefore, the light intensity of each pixel of the image pickup device 25 is measured while sequentially shifting the liquid crystal unit to which the electric field is applied and gradually moving the position of the light transmitting portion 26a of the spatial modulation device 26. The intensity of each direction of light can be recorded.

Further, in the present embodiment, the concave mirror 22 is arranged in front of the imaging lens 24 so that the imaging lens 24
Can be made smaller than in the case of FIG. 1, and the cost can be reduced accordingly. That is, since the size of the pupil of the imaging lens used in the present invention is the size of the viewing area of the obtained stereo image, a lens having a relatively large aperture is required, but a concave mirror is provided in front of the imaging lens 24. By arranging 22, the imaging lens 24 can be downsized without such a problem.

As described above, in the three-dimensional image recording apparatus of this embodiment, the object light from the subject 21 is incident, the concave mirror 22 that reflects the incident light and the reflected light from the concave mirror 22 are incident, and the result is obtained. An image forming lens 24 that forms an image 23 of the subject 21 at the image position, an image pickup element 25 that is arranged at the image forming position of the image forming lens 24, the image forming lens 24, and the image pickup element 2
5, a light transmitting portion 2 that transmits only a part of the object light from the subject 21 and is freely movable in its position.
And a spatial modulation element 26 having 6a.

Therefore, since there is no driving portion for photographing as in the conventional case, the three-dimensional image can be recorded at high speed, and the possibility of recording the three-dimensional image in real time can be obtained. In addition, it is possible to reduce the size of the entire apparatus because there is no driving portion for photographing.
Further, since it is not necessary to place the subject 21 on the rotary stage as in the conventional case, the subject 21 to be targeted is not restricted as in the conventional case. On the other hand, since the concave mirror 22 is arranged in front of the imaging lens 24, the imaging lens 24 can be downsized and the cost can be reduced accordingly.
As a result, the overall size of the device can be further reduced.

Further, on the same straight line as the subject 21, the concave mirror 22, the imaging lens 24, the image pickup device 25, and the spatial modulation device 2 are arranged.
There is no restriction that each optical element such as 6 must be arranged. That is, by changing the angle of the concave mirror 22 according to the position of the subject 21, the image forming position can be arbitrarily changed.

In each of the above embodiments, the spatial modulator 1
Although the case where the liquid crystal panel is used as the elements 5 and 26 is not limited to this, as long as it is an element that transmits only a part of the reflected light from the subject and has a light transmitting portion whose position can be arbitrarily moved, It is also possible to use the element of.

In each of the above embodiments, the imaging lens 1
Although the case where the image pickup devices 14 and 25 are arranged at the image forming positions of 3 and 24 has been described, the present invention is not limited to this, and the image forming lens 13 and
Even if the image pickup devices 14 and 25 are arranged in the vicinity of the image forming position of 24, the same effect as described above can be obtained.

Further, in each of the above embodiments, the spatial modulators 15 and 26 are arranged at the focal positions of the imaging lenses 13 and 24 or in the vicinity thereof, so that the translucent portions 15a of the spatial modulators 15 and 26, Subject 1 incident on 26a
Since the object lights from 1 and 21 are incident on the imaging lenses 13 and 24 in the same direction, it is possible to easily determine the position in the direction of the subjects 11 and 21.

Furthermore, in each of the above embodiments, the shapes of the light transmitting portions 15a and 26a of the spatial modulation elements 15 and 26 are as follows.
Although the case where the slit-shaped one is formed is described, the present invention is not limited to this, and the same effect as described above can be obtained when the slit-shaped one is circular, square, or triangular as shown in FIG. 4, for example. is there.

[0043]

As described above, according to the present invention, an object lens from an object is incident and an image forming lens for forming an image of the object at an image forming position (or an object light from the object is A concave mirror that is incident and reflects the incident light, and an imaging lens that receives reflected light from the concave mirror and that forms an image of a subject at an image forming position, and an image forming position of the image forming lens or a position in the vicinity thereof. A spatial modulation having an image pickup element provided and a light transmitting section which is provided between the imaging lens and the image pickup element, transmits only part of the object light from the subject, and the position of which is freely movable. Since it is provided with the element, it is possible to provide a highly reliable three-dimensional image recording apparatus capable of recording a three-dimensional image at high speed and reducing the size of the apparatus.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an embodiment of a three-dimensional image recording apparatus according to the present invention.

FIG. 2 is a front view showing a configuration example of a spatial light modulator according to the same embodiment.

FIG. 3 is a schematic view showing another embodiment of the three-dimensional image recording apparatus according to the present invention.

FIG. 4 is a front view showing another configuration example of the spatial light modulator according to the present invention.

FIG. 5 is a schematic diagram showing a conventional method for obtaining a parallax image used as an original image of a stereoscopic display.

FIG. 6 is a schematic diagram showing a conventional method for obtaining a parallax image used as an original image of a stereoscopic display.

[Explanation of symbols]

11 ... Subject, 12 ... Image of subject 11, 13 ... Imaging lens, 14 ... Image sensor, 15 ... Spatial modulator, 15a ... Translucent part, 21 ... Subject, 22 ... Concave mirror, 23 ... Subject 21
Image, 24 ... Image forming lens, 25 ... Imaging element, 26 ... Spatial modulation element, 26a ... Light transmitting section.

Claims (7)

[Claims] 1. An imaging lens which receives an object light from a subject and forms an image of the subject at an imaging position, and an imaging device which is arranged at an imaging position of the imaging lens or a position in the vicinity thereof. And a spatial modulation element that is disposed between the imaging lens and the image sensor and that has a light-transmitting portion that transmits only part of the object light from the subject and that is freely movable in its position. A three-dimensional image recording device characterized by comprising. 2. The three-dimensional image recording apparatus according to claim 1, wherein a liquid crystal panel is used as the spatial modulation element. 3. The three-dimensional image recording apparatus according to claim 1, wherein the spatial modulation element is arranged at a focal position of the imaging lens or a position in the vicinity thereof. 4. A concave mirror that receives object light from a subject and reflects the incident light, and an imaging lens that receives reflected light from the concave mirror and forms an image of the subject at an imaging position. An image pickup device disposed at an image forming position of the image forming lens or a position in the vicinity thereof, and arranged between the image forming lens and the image pickup device to transmit only part of object light from the subject and A three-dimensional image recording device comprising: a spatial modulation element having a light-transmitting portion whose position is freely movable. 5. The three-dimensional image recording device according to claim 4, wherein a liquid crystal panel is used as the spatial modulation element. 6. The three-dimensional image recording apparatus according to claim 4, wherein the spatial modulation element is arranged at a focal position of the imaging lens or a position in the vicinity thereof. 7. The three-dimensional image recording apparatus according to claim 4, wherein the image forming position is arbitrarily changed by changing the angle of the concave mirror according to the position of the subject.