JP2021060469A - Stereoscopic image projection device and projector - Google Patents

Abstract

To provide a stereoscopic image projection device and a projector, which can be miniaturized.SOLUTION: A stereoscopic image projection device includes: a first lens system; an image reproducing part which is arranged between a front side focal position of the first lens system and the first lens system and displays hologram representing a stereoscopic image so that the stereoscopic image of a virtual object is reproduced in a changeable first position via the first lens system; a filter which is arranged at the rear side focal position of the first lens system and removes the zero order light and the conjugate light included in the light from the hologram; a second lens system which projects the stereoscopic image reproduced at a first position to the second position corresponding to the first position; and an arithmetic part for calculating the hologram according to the first position.SELECTED DRAWING: Figure 1

Description

The present invention relates to a stereoscopic image projection device and a projector.

In recent years, technologies such as VR (Virtual Reality) and AR (Augmented Reality) have reached the stage of practical use, and stereoscopic image projection devices such as projectors using holography are attracting attention as one of the application fields. Since the stereoscopic image projection device using holography can freely change the depth of the display image electronically, the user can see a natural display image similar to the case where the real object exists at that depth. ..

For a stereoscopic image projection device using holography, an optical system as hardware is important, and a computer-generated hologram (CGH) technology for generating hologram data is important. For example, Non-Patent Document 1 describes a technique for performing processing such as correction required in an optical system with a computer composite hologram.

Yuji Sakamoto, "Construction Method of Small Head Mounted Display Using Computer Synthetic Hologram", IEICE Transactions C Vol. J102-C No. 6 pp. 205-211

In a stereoscopic image projection device using holography, a 4f optical system is generally used. However, in the stereoscopic image projection device using the 4f optical system, since the 4f optical system itself is large, the device also becomes large.

Therefore, an object of the present invention is to provide a stereoscopic image projection device and a projector that can be miniaturized.

The holographic image projection device according to the embodiment of the present invention is arranged between the first lens system, the front focal position of the first lens system, and the first lens system, and is arranged via the first lens system. , The image reproduction unit that displays the hologram representing the stereoscopic image and the rear focal position of the first lens system are arranged so that the stereoscopic image of the virtual object is reproduced in the changeable first position, from the hologram. A filter that removes the 0th-order light and the conjugate light contained in the light, and a second lens system that projects the stereoscopic image reproduced at the first position to the second position corresponding to the first position. It is characterized by having a calculation unit for calculating a hologram according to a first position.

The projector according to the embodiment of the present invention includes the above-mentioned stereoscopic image projection device and
It is characterized by including a screen that reflects the reproduced light of the stereoscopic image before being projected to the second position by the second lens system and projects the stereoscopic image to the third position.

According to the present invention, a stereoscopic image projection device and a projector capable of miniaturization are provided.

It is a figure which showed schematic the structure of the stereoscopic image projection apparatus which concerns on one Embodiment. It is a figure which showed an example of the structure of the stereoscopic image projection apparatus applied to a projector together with a reproduction light source. It is a figure for demonstrating an example of the calculation method of the object light in a computer composite hologram. It is a figure for demonstrating the method of calculating the virtual object position according to the optical system of a stereoscopic image projection apparatus. It is a figure for demonstrating the method of calculating the virtual object position according to the position of the reproduction light source of a stereoscopic image projection apparatus. It is a figure for demonstrating the method of calculating the virtual object position according to the optical system of the projector shown in FIG.

The stereoscopic image projection device of the present invention is arranged near an image reproduction unit that displays an electronic hologram or the like, and projects a first lens system for forming a stereoscopic image of a virtual object and a reproduced stereoscopic image. Has a second lens system for. Then, a filter for removing the 0th-order light and the conjugated light contained in the light from the image reproducing unit is arranged at the rear focal position of the first lens system.

Since the optical system of such a three-dimensional image projection device of the present invention is simple as compared with the projection device including the 4f optical system, a three-dimensional image projection device and a projector that can be miniaturized are provided.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the following embodiments, and can be appropriately modified without departing from the gist thereof. In addition, those having the same or equivalent functions in each figure may be designated by the same reference numerals, and the description thereof may be omitted or simplified.

FIG. 1 is a diagram schematically showing the configuration of the stereoscopic image projection device 1 according to the embodiment. The stereoscopic image projection device 1 has an image reproduction unit 2, a first lens system 3a, a filter 4, and a second lens system 3b in order from the object side along the optical axis OA. Further, the stereoscopic image projection device 1 has a calculation unit 5.

The image reproduction unit 2 has, for example, a liquid crystal display device in which pixels that can individually control the light transmittance are arranged in a two-dimensional manner. When the transmittance of each pixel is controlled by the calculation unit 5 described later, this liquid crystal display device functions as a hologram that generates regenerated light for reproducing a three-dimensional image of a virtual object when irradiated with regenerated illumination light. .. The image reproduction unit 2 may reproduce the stereoscopic image on the same front side when the reproduction illumination light is irradiated from the front side, or may reproduce the stereoscopic image on the front side when the reproduction illumination light is irradiated from the back side. You may play it. As the image reproduction unit 2, for example, LCos (Liquid crystal on silicon) capable of displaying a hologram is used.

The image reproduction unit 2 is arranged between the front focal position (that is, the focal position on the object side) of the first lens system 3a and the first lens system 3a, and can be changed via the first lens system 3a. A hologram representing the stereoscopic image of the virtual object is displayed so that the stereoscopic image is reproduced at the first position p1. The image reproduction unit 2 is preferably arranged at a position where the distance from the front principal point of the first lens system 3a is closer than half of the focal length f1 of the first lens system 3a. As a result, the stereoscopic image projection device 1 is miniaturized. The image reproduction unit 2 may be arranged so as to be in contact with the first lens system 3a.

The first lens system 3a has one or more lenses along the optical axis OA, and images the light from the hologram of the image reproducing unit 2 at the first position p1 to form a three-dimensional image of a virtual object. Play it.

The filter 4 is arranged at the rear focal position (that is, the focal position on the image side) of the first lens system 3a, and removes the 0th-order light and the conjugated light contained in the light from the hologram. Since the directions of the 0th-order light and the conjugate light from the image reproduction unit 2 are different from the directions of the reproduction light for reproducing the stereoscopic image of the virtual object, the 0th-order light, the conjugate light, and the reproduction light are different at the rear focal position. Transparent to different areas. Therefore, the filter 4 allows light to pass through a region through which the regenerated light is transmitted, and shields each region through which the 0th-order light and the conjugate light are transmitted to transmit the regenerated light while transmitting the 0th-order light and the conjugate. Light can be removed. As the filter 4, for example, at the rear focal position, a light-shielding plate arranged so as to shield each region through which the 0th-order light and the conjugated light are transmitted and to allow light to pass through the other regions is used.

The second lens system 3b has one or more lenses along the optical axis OA, and projects the stereoscopic image reproduced at the first position p1 at the second position p2 corresponding to the first position p1. To do. As a result, the observer observes the stereoscopic image projected at the second position p2 in the real space.

The calculation unit 5 has a processor, a memory, a communication I / F, and the like. As the calculation unit 5, for example, a PC (Personal Computer) is used. The processor has one or more arithmetic circuits and peripheral circuits thereof. The memory includes a semiconductor memory such as an HDD (Hard Disk Drive), an optical recording medium, a RAM (Random Access Memory) and a ROM (Read Only Memory), or a storage medium in combination thereof. The communication I / F connects the processor to the image reproduction unit 2 by wire or wirelessly, and enables the processor to communicate with the image reproduction unit 2.

The processor of the arithmetic unit 5 executes a computer program stored in the memory, calculates a hologram for reproducing a three-dimensional image of a virtual object at the first position p1, and displays the liquid crystal of the image reproduction unit 2 according to the hologram. Calculate the light transmittance at each pixel of the device. Then, the processor transmits the calculated transmittance data to the image reproduction unit 2 via the communication I / F, and sets each pixel of the liquid crystal display device of the image reproduction unit 2 to the image reproduction unit 2. Display the hologram.

FIG. 2 is a diagram showing an example of the configuration of the stereoscopic image projection device 1 applied to the projector 9 together with the reproduction light source 6. The projector 9 shown in FIG. 2 has a reproduction light source 6, a beam splitter 7a, a prism 7b, and a screen 8 in addition to the configuration shown in FIG.

As shown in FIG. 2, each optical element included in the projector 9 has an image reproduction unit 2, a first lens system 3a, a beam splitter 7a, a prism 7b, a filter 4, and a second from the object side along the optical axis OA. The lens system 3b and the screen 8 are arranged in this order. Further, the reproduction light source 6 is arranged at a position where the optical axis OA before being turned to the prism 7b by the beam splitter 7a is extended. The image reproduction unit 2 shown in FIG. 2 reproduces a stereoscopic image on the same side as the side irradiated with the reproduction illumination light.

The reproduction light source 6 irradiates the image reproduction unit 2 with the reproduction illumination light via the beam splitter 7a and the first lens system 3a. The reproduction light source 6 is preferably arranged at the rear focal position of the first lens system 3a. As a result, the regenerated illumination light emitted from the regenerated light source 6 becomes light parallel to the optical axis OA by the first lens system 3a and is irradiated to the image reproducing unit 2. As the reproduction light source 6, for example, an RGB laser light source that irradiates coherent light is used. In this case, the RGB laser light source sequentially irradiates each monochromatic light of R (red) G (green) B (blue) at a fixed cycle according to the control by the calculation unit 5. Further, the calculation unit 5 calculates a hologram corresponding to each monochromatic light according to the timing when each monochromatic light is irradiated to the image reproduction unit 2 from the RGB laser light source, and displays the hologram on the liquid crystal display device of the image reproduction unit 2. .. As a result, the stereoscopic image is projected in color. As the reproduction light source 6, a single-color laser light source may be used in addition to the RGB laser light source.

The beam splitter 7a is arranged between the reproduction light source 6 and the first lens system 3a. The regeneration illumination light emitted from the reproduction light source 6 passes through the beam splitter 7a and heads toward the image reproduction unit 2 via the first lens system 3a. Further, the reproduced light incident from the image reproducing unit 2 through the first lens system 3a is reflected by the beam splitter 7a and directed toward the prism 7b. A half mirror or the like may be used instead of the beam splitter 7a.

The prism 7b is arranged between the beam splitter 7a and the filter 4 along the optical axis OA. The regenerated light incident from the beam splitter 7a is reflected by the prism 7b and directed toward the filter 4, and the 0th-order light and the conjugate light are removed by passing through the filter 4 to form a stereoscopic image at the first position p1. .. This stereoscopic image is projected at the second position p2 by the second lens system 3b.

The screen 8 is arranged along the optical axis OA on the rear side of the second lens system 3b. The screen 8 reflects the reproduced light of the stereoscopic image before being projected to the second position p2 by the second lens system 3b, and projects the stereoscopic image to the third position p3. As a result, the user of the projector 9 observes the stereoscopic image projected at the third position p3 in the real space. The reflective surface of the screen 8 may have a concave curved surface as shown in FIG. 2 and have a positive power. As a result, the projector 9 is miniaturized.

FIG. 3 is a diagram for explaining an example of a method of calculating object light in a computer composite hologram. Various algorithms have been proposed as a method for calculating object light in a computer-synthesized hologram. As an example, a _{point light source method assuming that the surface of an object is a set of point light sources g i} (i is a natural number 1 ... N). Will be described. In the point light source method, the object light u (x, y) at one point (x, y) on the hologram is represented by the following equation (1) as a superposition of spherical waves from _{each point light source g i on the surface of the object.} It shall be. Here, λ is _{the wavelength of the light from the point light source g i} , the reference light, and the reproduction illumination light, a _i is the intensity of the light in the point light source g _{i , and r i} is from the point light source g _i. It is the distance to one point (x, y) on the hologram.

The calculation unit 5 assumes that the object is located at the virtual object position p0 in the virtual space, and the object light u (x, y) from this virtual object interferes with the reference light R (x, y) to reproduce the image. The virtual interference fringes I (x, y) formed at the position 2 are calculated by the following equation (2).

Then, the calculation unit 5 transmits light in each pixel of the liquid crystal display device of the image reproduction unit 2 so that the interference fringes I (x, y) of the above equation (2) are displayed on the image reproduction unit 2 as a hologram. The rate is calculated, and the image reproduction unit 2 is controlled so that each pixel of the liquid crystal display device has the transmittance. As a result, the hologram is displayed on the image reproduction unit 2.

When an RGB laser light source is used as the reproduction light source 6, the calculation unit 5 sets the interference fringes I (x, y) corresponding to each monochromatic light of R (red) G (green) B (blue) by the above equation. In (1), the calculation is performed using the wavelength λ of each monochromatic light.

When the image reproduction unit 2 on which the hologram is displayed is irradiated with the reproduction illumination light having the same wavelength as the reference light R (x, y) from the same direction as the reference light R (x, y), the following equation (3) The light w (x, y) represented by is generated by the hologram.

Substituting the above equation (2) into the above equation (3) gives the following equation (4).

The first and fourth terms of the above equation (4) are terms proportional to the emitted reproduction illumination light. For example, in the image reproduction unit 2 shown in FIG. 2, the hologram is directly transmitted and reflected by the reproduction illumination. It represents the 0th-order light, which is light. The second term of the above equation (4) is a term proportional to the object light u (x, y) and represents the regenerated light for reproducing the three-dimensional image of the virtual object. Further, the third term of the above equation (4) is a term proportional to the complex conjugate of the object light u (x, y), and reproduces a so-called pseudo-scopic image in which the unevenness of the virtual object is inverted. Represents the conjugate light.

In this way, the calculation unit 5 can freely calculate the object light u (x, y) from the virtual object at the arbitrary virtual object position p0 by using the computer composite hologram technology, so that the stereoscopic image The virtual object position p0 can also be calculated according to the optical system of the projection device 1.

FIG. 4 is a diagram for explaining a method of calculating the virtual object position p0 according to the optical system of the stereoscopic image projection device 1.

According to the lens formula, for a lens system having a focal length f, an object having a distance from the front principal point of the lens system a and an image having a distance b from the rear principal point of the lens system are connected to each other. When there is an image relationship, the following equation (5) is satisfied.

First, the above equation (5) is applied to the second lens system 3b. Therefore, as shown in FIG. 4, the z-axis is set along the optical axis OA of the second lens system 3b, and the x-axis is orthogonal to the z-axis at the front principal point h of the second lens system 3b. To set. Then, the front principal point h of the second lens system 3b is set as the origin.

In the local coordinate system (x, z) set for the second lens system 3b, substituting f = f2, a = −z1, and b = z2-t2 into the above equation (5), the following equation (5-) 1) is obtained. Here, f2 is the focal length of the second lens system 3b, and t2 is the distance from the front principal point to the rear principal point of the second lens system 3b.

By modifying the above equation (5-1), the following equation (6-1) is obtained.

Therefore, the calculation unit 5 has the first position p1 (x2, z2) for projecting the stereoscopic image to the desired second position p2 (x2, z2) by the second lens system 3b according to the above equation (6-1). x1, z1) can be calculated. Specifically, the calculation unit 5 sets the first position p1 to the focal length f2 of the second lens system 3b so that the second lens system 3b has an imaging relationship with the second position p2. Calculate based on.

Next, the above equation (5) is applied to the first lens system 3a. Therefore, as shown in FIG. 4, the z'axis is set along the optical axis OA of the first lens system 3a so as to be orthogonal to the z'axis at the front principal point h'of the first lens system 3a. Set the x'axis to. Then, the origin is the front principal point h'of the first lens system 3a.

In the local coordinate system (x', z') set for the first lens system 3a, substituting f = f1, a = -z0, b = z1-t1 into the above equation (5), the following equation ( 5-2) is obtained. Here, f1 is the focal length of the first lens system 3a, and t1 is the distance from the front principal point to the rear principal point of the first lens system 3a.

By modifying the above equation (5-2), the following equation (6-2) is obtained.

The coordinate conversion formula from the local coordinate system (x', z') set for the first lens system 3a to the local coordinate system (x, z) set for the second lens system 3b is the following formula ( It is given in 7-1). Here, d1 is the distance from the front principal point of the first lens system 3a to the front principal point of the second lens system 3b.

By transforming the coordinates of the above equation (6-2) by the above equation (7-1), the following equation (8-1) is obtained.

Therefore, the calculation unit 5 uses the above equation (8-1) to reproduce the stereoscopic image at the first position p1 (x1, z1) by the first lens system 3a at the virtual object position p0 (x0, z0). ) Can be calculated. Specifically, the calculation unit 5 sets the virtual object position p0 based on the focal length f1 of the first lens system 3a so that the first lens system 3a has an imaging relationship with the first position p1. To calculate.

Then, the calculation unit 5 calculates a hologram when the virtual object exists at the virtual object position p0 (x0, z0) according to the above equations (1) and (2), and displays the calculated hologram. The image reproduction unit 2 is controlled. As a result, the optical system of the stereoscopic image projection device 1 projects the stereoscopic image at the desired second position p2. The desired second position p2 is stored in the memory in advance as data referenced by, for example, a computer program that projects a stereoscopic image, and is input to the calculation unit 5 by the computer program.

As described above, the stereoscopic image projection device 1 of the present embodiment uses the technique of computer-synthesized hologram even if it is a simple optical system composed of two first lens systems 3a and a second lens system 3b. Therefore, the stereoscopic image can be projected at the desired second position p2. Further, the stereoscopic image projection device 1 can also move the stereoscopic image to a desired second position p2 to show it.

FIG. 5 is a diagram for explaining a method of calculating the virtual object position p0 according to the position of the reproduction light source 6 of the stereoscopic image projection device 1. In FIG. 5, the z-axis is set so as to be orthogonal to the display surface of the hologram of the image reproduction unit 2, and the x-axis is set in the display surface of the hologram of the image reproduction unit 2. The origin is the intersection of the z-axis and the x-axis.

In the coordinate system shown in FIG. 5, the object light from the object arranged at the position p0 (x0, z0) interferes with the reference light from the reference light source arranged at the position p4 (x4, z4) to reproduce the image. It is assumed that a hologram is formed in the part 2. Then, when the image reproduction unit 2 is irradiated with the reproduction illumination light from the reproduction light source 6 arranged at the same position p4 (x4, z4) as the reference light source, the stereoscopic image is reproduced at the position p5 (x5, z5) by the hologram. Suppose it was done.

In this case, according to the imaging formula, when the image reproduction unit 2 is irradiated with the reproduction illumination light from the reproduction light source 6 arranged at the position p6 (x6, z6) different from the position p4 (x4, z4), the lower part The stereoscopic image is reproduced at the position p7 (x7, z7) that satisfies the equation (9). Here, the positive sign in the following equation (9) shows the case of a direct image, and the negative sign shows the case of a conjugate image.

Therefore, even if the position of the virtual reference light source in the computer composite hologram and the position of the actual reproduction light source 6 are different, the calculation unit 5 reproduces the stereoscopic image at a desired position by using the above equation (9). It is also possible to calculate the virtual object position p0 to be performed.

As shown in FIG. 2, when the reproduction light source 6 is arranged at the focal position of the first lens system 3a, the reproduction illumination light emitted from the reproduction light source 6 is the optical axis of the first lens system 3a. The light becomes parallel to the OA and is applied to the image reproduction unit 2. In this case, if the calculation unit 5 calculates the reference light as light parallel to the optical axis OA like the reproduction light source 6, the stereoscopic image is reproduced at the same position regardless of the positions of the reference light source and the reproduction light source 6. To.

As described above, the stereoscopic image projection device of the present embodiment is arranged between the first lens system, the front focal position of the first lens system, and the first lens system, and is via the first lens system. The hologram is arranged at the rear focal position of the first lens system and the image reproduction unit that displays the hologram representing the stereoscopic image so that the stereoscopic image of the virtual object is reproduced at the first changeable position. A filter that removes the 0th-order light and conjugated light contained in the light from the lens, and a second lens system that projects the stereoscopic image reproduced at the first position to the second position according to the first position. It is characterized by having a calculation unit for calculating a hologram according to a first position. This provides a stereoscopic image projection device and a projector that can be miniaturized.

The above-described embodiments are merely examples of embodiment in carrying out the present invention, and the technical scope of the present invention should not be construed in a limited manner by these. That is, the present invention can be implemented in various forms without departing from the technical idea or its main features.

For example, as a modification, in the filter 4, the position of the region through which the 0th-order light and the conjugate light pass through the filter 4 changes with changes in the optical system of the stereoscopic image projection device 1 or the configuration of the reproduction light source 6. The position of the light-shielding region may be changed accordingly. Therefore, the filter 4 is configured by using, for example, a liquid crystal device in which the transmission and non-transmission of light in a desired region can be controlled by the calculation unit 5. Further, the calculation unit 5 calculates a transmission region through which the 0th-order light and the conjugate light are transmitted at the rear focal position of the first lens system 3a according to the first position, and determines that this transmission region is non-transmissive. The liquid crystal device of the filter 4 is controlled so as to be. The calculation unit 5 can calculate the position of this transmission region from the diffraction angles of the 0th-order light and the conjugated light generated from the hologram. As a result, the filter 4 can remove the 0th-order light and the conjugated light contained in the light from the image reproducing unit 2 even when the position of the region through which the 0th-order light and the conjugated light are transmitted changes.

Further, as another modification, the calculation unit 5 displays an object image at a desired third position p3 in the stereoscopic image projection device 1 applied to the projector 9 as shown in FIG. The virtual object position p0 can also be calculated. FIG. 6 is a diagram for explaining a method of calculating the virtual object position p0 according to the optical system of the projector 9 shown in FIG. The projector 9 shown in FIG. 6 has a screen 8 shown in FIG. 2 in addition to the stereoscopic image projection device 1 shown in FIG. Since the screen 8 having a concave curved surface as shown in FIG. 2 can be optically equivalently treated as a convex lens, a calculation method in that case will be described below. FIG. 6 shows the screen 8 as a convex lens.

The above equation (5) is applied to the screen 8. Therefore, as shown in FIG. 6, the z'' axis is set along the optical axis OA of the screen 8, and the x'' axis is orthogonal to the z'' axis at the front principal point h'' of the screen 8. To set. Then, the origin is the front principal point h ″ of the screen 8.

In the local coordinate system (x'', z'') set for the screen 8, substituting f = f3, a = −z2, and b = z3-t3 into the above equation (5), the following equation (5-) 3) is obtained. Here, f3 is the focal length of the screen 8, and t3 is the distance from the front principal point to the rear principal point of the screen 8.

By modifying the above equation (5-3), the following equation (6-3) is obtained.

The coordinate conversion formula from the local coordinate system (x'', z'') set for the screen 8 to the local coordinate system (x, z) set for the second lens system 3b is the following formula (7-). Given in 2). Here, d2 is the distance from the front principal point of the second lens system 3b to the front principal point of the screen 8.

By transforming the coordinates of the above equation (6-3) by the above equation (7-2), the following equation (8-2) is obtained.

Therefore, the calculation unit 5 uses the above equation (8-2) to project the stereoscopic image to the desired third position p3 (x3, z3) by the screen 8 at the second position p2 (x2, z2). Can be calculated. Specifically, the calculation unit 5 calculates the second position p2 based on the focal length f3 of the screen 8 so that the screen 8 has an imaging relationship with the third position p3. Then, the calculation unit 5 calculates the virtual object position p0 for projecting the stereoscopic image at the second position p2 (x2, z2) by the above equations (6-1) and the above equation (8-1). be able to.

1 Stereoscopic image projection device 2 Image reproduction unit 3a First lens system 3b Second lens system 4 Filter 5 Calculation unit 6 Reproduction light source 7a Beam splitter 7b Prism 8 Screen 9 Projector

Claims (5)

The first lens system and
A stereoscopic image of a virtual object is reproduced at a first position that can be changed via the first lens system, which is arranged between the front focal position of the first lens system and the first lens system. As described above, the image reproduction unit that displays the hologram representing the stereoscopic image and
A filter arranged at the rear focal position of the first lens system and removing the 0th-order light and the conjugated light contained in the light from the hologram.
A second lens system that projects the stereoscopic image reproduced at the first position to a second position corresponding to the first position, and
An arithmetic unit that calculates the hologram according to the first position,
A stereoscopic image projection device characterized by having. The image reproduction unit is arranged at a position where the distance from the front principal point of the first lens system is closer than half of the focal length of the first lens system.
The stereoscopic image projection device according to claim 1. The calculation unit
With respect to the second lens system, the first position is calculated based on the focal length of the second lens system so as to have an imaging relationship with the second position.
With respect to the first lens system, the virtual object position is calculated based on the focal length of the first lens system so as to have an imaging relationship with the first position.
The hologram is calculated assuming that the virtual object exists at the position of the virtual object.
The stereoscopic image projection device according to claim 1 or 2. The filter is configured by using a liquid crystal device capable of controlling the transmission and non-transmission of light.
The calculation unit calculates a transmission region through which the 0th-order light and the conjugate light pass through the liquid crystal device according to the first position, and controls the liquid crystal device so that the transmission region is non-transmissive.
The stereoscopic image projection device according to any one of claims 1 to 3. The stereoscopic image projection device according to any one of claims 1 to 4.
A screen that reflects the reproduced light of the stereoscopic image before being projected to the second position by the second lens system and projects the stereoscopic image to the third position.
A projector characterized by being equipped with.

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