JP2023114496A - Hologram data generator, electronic holography display device, and program thereof - Google Patents

Abstract

To provide a hologram data generator which can generate hologram data with reduced information amount.SOLUTION: A hologram data generator 1 includes: phase addition means 10 for adding a phase to object target data and generating a complex amplitude distribution; propagation calculation means 11 for calculating the complex amplitude distribution of a hologram surface by a propagation calculation; hologram data calculation means 12 for calculating hologram data from the complex amplitude distribution of the hologram surface and the complex amplitude distribution of reference light; and hologram data thinning means 13 for thinning data in a preset missing pixel position from the hologram data calculated by the hologram data calculation means 12.SELECTED DRAWING: Figure 1

Description

The present invention relates to a hologram data generation device, an electronic holography display device, and programs thereof.

Holography is a technology capable of faithfully reproducing the wavefront of light emitted from a subject by utilizing interference and diffraction of light. This holography is known as an ideal three-dimensional image technology without vergence accommodation contradiction. A medium in which three-dimensional information of a subject is recorded using holographic technology is called a hologram. Electronic holography is a technique for displaying three-dimensional images as moving images by treating this hologram as digital data and displaying the hologram data on a spatial light modulator (SLM), which is an electronic device.

The angle at which a three-dimensional image reproduced by electronic holography can be correctly observed (viewing zone angle 2θ) depends on the pixel pitch p of the SLM and the wavelength λ of incident light, 2θ=2sin ⁻¹ [λ/(2p) ]. Therefore, in order to expand the viewing angle, it is necessary to narrow the pixel pitch of the SLM.
On the other hand, when the number of pixels in the width direction of the SLM is Nx, the number of pixels in the height direction of the SLM is Ny, and the pixel pitch of the SLM is p, the area S of the SLM is S=p ² NxNy. In order to enlarge the image screen, it is necessary to increase the number of pixels of the SLM.
Conventionally, as a technique for enlarging such a three-dimensional image, there is a technique for realizing a large screen by arranging a plurality of SLMs in the horizontal and vertical directions to increase the number of pixels in the entire SLM (Patent Reference 1).

JP 2014-215332 A

In hologram reproduction, for example, an SLM with a pixel pitch of 1 μm is required to obtain a viewing angle of 30° at a wavelength of 532 nm. For example, when using an SLM with a size of 10 cm ² , it is necessary to handle huge hologram data of 100 k×100 k pixels.
As described above, in the conventional method, when a three-dimensional image is enlarged, the amount of information in the hologram data becomes enormous. There is a problem that it takes a long time to write to the display device.

SUMMARY OF THE INVENTION The present invention has been made in view of such conventional problems. An object of the present invention is to provide an electronic holography display device and a program thereof.

In order to solve the above-mentioned problems, a hologram data generation device according to the present invention is a hologram data generation device for generating hologram data in which some pixels are missing from subject data, which is three-dimensional data, and phase adding means and , propagation calculation means, hologram data calculation means, and hologram data thinning means.

In such a configuration, the hologram data generation device generates a complex amplitude distribution by adding a phase to the subject data using the phase addition means.
Then, the hologram data generating device calculates the complex amplitude distribution of the hologram plane from the complex amplitude distribution of the subject data by propagation calculation by the propagation calculation means.
Then, the hologram data generating device calculates hologram data from the complex amplitude distribution of the hologram plane and the complex amplitude distribution of the reference light by the hologram data calculation means. Hologram data is thus generated.

Furthermore, the hologram data generation device thins out the data of the preset defective pixel position from the hologram data calculated by the hologram data calculation means by the hologram data thinning means. This reduces the information amount of the hologram data.
In this way, the hologram data in which the pixels are thinned out is displayed as a reconstructed image of the subject by interpolating the missing pixels with arbitrary pixel values in the electronic holography display device. In this case, the user does not recognize the position of the defective pixel in the reconstructed image of the subject due to the hologram reconstruction.
The hologram data generation device can operate with a hologram data generation program for causing a computer to function as each means described above.

Further, in order to solve the above problems, an electronic holography display device according to the present invention is an electronic holography display device for inputting defective hologram data in which a part of a pixel is missing and displaying a reconstructed image of a subject, wherein missing pixel interpolation is performed. means, display means, and light emitting means.

In such a configuration, the electronic holography display device interpolates pixels into the missing pixels of the missing hologram data by the missing pixel interpolating means.
Then, the electronic holography display device displays the hologram data in which the missing pixels are interpolated by the missing pixel interpolating means. The display means can consist of a spatial light modulator.
Then, the electronic holography display device irradiates the spatial light modulator, which is the display means, with illumination light by means of the light emitting means. As a result, the reconstructed image of the subject is displayed.
The electronic holographic display device can be operated with an electronic holographic display program for causing the computer to function as each means described above.

ADVANTAGE OF THE INVENTION This invention has the outstanding effect shown below.
According to the present invention, it is possible to generate hologram data with a reduced amount of information. Further, according to the present invention, a reproduced image can be displayed using hologram data with a reduced amount of information.
As a result, the present invention can shorten the time for recording hologram data, the time for transmission, and the time for writing to the display device, compared to the conventional art.

1 is a block configuration diagram showing the configuration of a hologram data generation device according to an embodiment of the present invention; FIG. FIG. 2 is an explanatory diagram for explaining processing of calculating a complex amplitude distribution of a hologram plane from a complex amplitude distribution of a tomographic image, which is performed by the propagation calculation means of FIG. 1; 2 is an explanatory diagram for explaining an example of thinning hologram data for each row in the hologram data thinning means of FIG. 1; FIG. 2 is an explanatory diagram for explaining an example of thinning hologram data for each column in the hologram data thinning means of FIG. 1; FIG. 2 is an explanatory diagram for explaining an example of thinning hologram data for each block in the hologram data thinning means of FIG. 1; FIG. 2 is an explanatory diagram for explaining an example of randomly thinning out hologram data in the hologram data thinning means of FIG. 1; FIG. 4 is a flow chart showing the operation of the hologram data generation device according to the embodiment of the present invention; 1 is a block configuration diagram showing the configuration of an electronic holography display device according to an embodiment of the present invention; FIG. 4 is a flow chart showing the operation of the electronic holographic display device according to the embodiment of the present invention; Graph showing image quality evaluation between an image obtained by simulating reproduction of hologram data in which missing pixels are interpolated by thinning and the original image, where the horizontal axis represents the ratio of missing pixels to all pixels (missing data amount [%]). , the vertical axis indicates PSNR (maximum signal-to-noise ratio [dB]). FIG. 10 is a block configuration diagram showing a modification of the hologram data generation device using the GS algorithm for propagation calculation; A graph showing image quality evaluation between an image obtained by simulating reproduction of hologram data in which missing pixels are interpolated by thinning using the GS algorithm for propagation calculation and the original image, and the horizontal axis is the ratio of missing pixels to all pixels. (missing data amount [%]), and the vertical axis indicates PSNR (maximum signal-to-noise ratio [dB]).

[Configuration of hologram data generation device]
First, the configuration of a hologram data generation device 1 according to an embodiment of the present invention will be described with reference to FIG.
The hologram data generation device 1 generates hologram data in which some pixels are missing from subject data, which is three-dimensional data.
The subject data may be any data as long as it is three-dimensional data. Here, an example of a tomographic image in which three-dimensional data is configured for each distance will be described.
As shown in FIG. 1, the hologram data generation device 1 includes phase addition means 10, propagation calculation means 11, hologram data calculation means 12, hologram data thinning means 13, and condition data storage means .

Phase adding means 10 adds a phase to object data to generate a complex amplitude distribution.
The phase addition means 10 inputs subject data through an input means (not shown). Then, the phase adding means 10 sets the value of each pixel of the object data as the amplitude, and adds an initial phase (for example, random phase, equal phase, linear phase, etc.) to each pixel. As a result, the subject data becomes a complex amplitude distribution.
The phase addition means 10 outputs the complex amplitude distribution generated by adding the initial phase to the propagation calculation means 11 .

The propagation calculation means 11 calculates a complex amplitude distribution of a predetermined hologram plane from the complex amplitude distribution of the subject data generated by the phase adding means 10 by propagation calculation. The propagation calculation in the propagation calculation means 11 is not particularly limited, and may be an angular spectrum method, a Fresnel propagation method, or the like.

Here, with reference to FIG. 2, an example in which the angular spectrum method is used for propagation calculation in the propagation calculation means 11 will be described.
Propagation calculation means 11 sets the display surface of the spatial light modulator (SLM 100) as a hologram surface H, and from a plurality of complex amplitude distributions U _i (x, y, z _i ) for each distance (z _i ) from the hologram surface H, , the complex amplitude distribution U(x, y, 0) in the hologram plane H is calculated.
Specifically, the propagation calculation means 11 uses the following formula (1), where N _z is the number of samplings in the depth direction of the tomographic image, and _zi is the propagation distance to the hologram surface H of the i-th tomographic image. , the complex amplitude distribution U(x, y, 0) at the hologram plane H(z=0).

Here, FT is Fast Fourier Transform (FFT), FT ⁻¹ is Inverse Fast Fourier Transform (IFFT), x and y are spatial coordinates, and u and v are spatial frequencies in the x and y directions, respectively.
At this time, the propagation calculation means 11 may have an indefinite value or a specific value (for example, "0") for the pixels at the positions where the hologram data stored in the condition data storage means 14 are to be lost. ) may be set.
Returning to FIG. 1, the description of the configuration of the hologram data generation device 1 is continued.

The propagation calculation means 11 outputs the complex amplitude distribution on the hologram plane calculated by the propagation calculation to the hologram data calculation means 12 .

The hologram data calculation means 12 calculates hologram data from the complex amplitude distribution of the hologram plane calculated by the propagation calculation means 11 and the complex amplitude distribution of the reference light.
The hologram data calculation means 12 calculates hologram data using the complex amplitude distribution U(x, y, 0) of the hologram plane as the complex amplitude distribution of the object light and the complex amplitude distribution of the reference light prepared in advance.

The complex amplitude distribution of the reference light is stored in the condition data storage means 14 in advance. The wavefront of the reference light may be an arbitrary wavefront such as a plane wave or a spherical wave.
Further, the hologram data generated by the calculation by the hologram data calculation means 12 may be of amplitude type, phase type, or complex amplitude type.
A general technique may be used for generating hologram data from the complex amplitude distribution of the object light and the complex amplitude distribution of the reference light, so detailed description is omitted here.
The hologram data calculation means 12 outputs the hologram data obtained by the calculation to the hologram data thinning means 13 .

The hologram data thinning-out means 13 thins out the data of preset defective pixel positions from the hologram data calculated by the hologram data calculating means 12 .
That is, the hologram data thinning means 13 thins out the data of the preset defective pixel positions to generate the defective hologram data.
Here, the defective pixel positions are stored in advance in the condition data storage means 14, and the hologram data thinning means 13 thins out the pixels at the defective pixel positions set in the condition data storage means 14 to generate defective hologram data. .

The hologram data thinning means 13 transmits the missing hologram data to the electronic holography display device (see FIG. 4) via transmission means (not shown). Alternatively, the hologram data thinning means 13 records the defective hologram data in a recording medium (not shown) and causes the electronic holography display device (see FIG. 4) to read the data.

Examples of missing pixel positions will now be described with reference to FIGS. 3A to 3D. Here, the hologram data HD is data of 16 pixels in the horizontal direction (x direction) and 16 pixels in the vertical direction (y direction), normal pixels (non-defective pixels) NP are represented in white, and defective pixels TP are represented in black. .

FIG. 3A shows an example of deleting (thinning) pixels from the hologram data HD for each row. Here, every fourth row is a missing pixel row. It should be noted that the number of defective pixel rows does not have to be one, and may be plural. Also, the intervals between defective pixel rows may not be equal.

FIG. 3B shows an example of deleting (thinning) pixels from the hologram data HD for each column. Here, every 4th row is a defective pixel row. Note that the number of defective pixel columns does not have to be one, and may be plural. Also, the intervals between the defective pixel columns may not be equal.

FIG. 3C shows an example of deleting (thinning) pixels from the hologram data HD for each block. Here, each pixel block of 2×2 pixels is defined as a defective pixel block. Note that the number of horizontal pixels and the number of vertical pixels of the defective pixel block are not limited to 2×2. Also, the intervals between the defective pixel blocks may not be equal.

FIG. 3D shows an example of missing (thinning) pixels at random positions from the hologram data HD. Here, an example is shown in which defective pixels are randomly set in the entire hologram data HD. However, it is also possible to randomly set defective pixels within a block of a predetermined size (eg, 8×8 pixel block) and set the block repeatedly in the horizontal and vertical directions.
Returning to FIG. 1, the description of the configuration of the hologram data generation device 1 is continued.

The condition data storage means 14 stores various condition data for generating hologram data. The condition data storage means 14 can be composed of a general storage medium such as a semiconductor memory.
The condition data storage means 14 preliminarily stores, as condition data, defective pixel position data indicating the positions of defective pixels used by the propagation calculation means 11 and the hologram data thinning means 13, the number of gradations, and the like. Moreover, the condition data storage means 14 stores in advance the complex amplitude distribution of the reference light used by the hologram data calculation means 12 as condition data.
The condition data storage means 14 further stores various conditions for generating hologram data, such as modulation method (phase modulation type, amplitude modulation type, complex amplitude modulation type), number of gradations, size of hologram, and the like. is stored.

As described above, the hologram data generation device 1 generates hologram data by thinning predetermined defective pixels by the hologram data thinning means 13. Therefore, when a three-dimensional image to be displayed is enlarged, the hologram data may be reduced. The amount of information can be reduced.
The hologram data generation device 1 can operate a computer (not shown) with a hologram data generation program for functioning as each means described above.

[Operation of hologram data generation device]
Next, the operation of the hologram data generation device 1 according to the embodiment of the present invention will be described with reference to FIG. 4 (see also FIG. 1 for the configuration). It is assumed that the condition data storage means 14 stores in advance various condition data for generating missing hologram data.

In step S1, the phase adding means 10 inputs object data, which is three-dimensional data, through an input means (not shown).
In step S2, the phase adding means 10 sets the value of each pixel of the object data input in step S1 as an amplitude, and adds an initial phase (for example, random phase) to each pixel. As a result, the object data has a complex amplitude distribution.
In step S3, the propagation calculation means 11 generates a complex amplitude distribution of a predetermined hologram plane from the complex amplitude distribution of the object data generated in step S2 by propagation calculation such as the angular spectrum method.

In step S4, the hologram data calculation means 12 uses the complex amplitude distribution on the hologram plane generated in step S3 as the complex amplitude distribution of the object light, and generates hologram data from the previously prepared complex amplitude distribution of the reference light.
In step S5, the hologram data thinning means 13 thins out the pixels at the defective pixel positions from the hologram data generated in step S4.
As a result, the hologram data generation device 1 can generate hologram data (missing hologram data) with a reduced data amount.

[Configuration of electronic holographic display device]
Next, the configuration of the electronic holography display device 2 according to the embodiment of the present invention will be described with reference to FIG.
The electronic holography display device 2 displays a reconstructed image of a subject from the defective hologram data generated by the hologram data generation device 1 (see FIG. 1).
As shown in FIG. 5 , the electronic holography display device 2 includes missing data storage means 20 , missing pixel interpolation means 21 , display means 22 and light emission means 23 .

The missing data storage means 20 pre-stores missing data information for interpolating missing pixels of missing hologram data. The missing data storage means 20 can be composed of a general storage medium such as a semiconductor memory.
The missing data storage means 20 stores in advance the positions of missing pixels, the number of gradations, etc. as missing data information. Note that a fixed pixel value to be assigned to all missing pixels may be set in the missing data information.

The missing pixel interpolating means 21 interpolates the missing pixels of the missing hologram data.
The missing pixel interpolating means 21 inputs the missing hologram data generated by the hologram data generating device 1 (see FIG. 1) through an input means (not shown). Then, the missing pixel interpolating means 21 interpolates missing pixels in the missing hologram data by inserting pixels into the missing pixel positions stored in the missing data storage means 20 . At this time, the value of the pixel to be interpolated may be any value, or the pixel value stored in the missing data storage means 20 may be used.
The position of the defective pixel need not be stored in advance in the defective data storage means 20, and may be input from the outside as data associated with the defective hologram data.

Thereby, the defective pixel interpolating means 21 can generate the hologram data HD by interpolating the defective pixels TP shown in FIGS. 3A to 3D, for example.
The missing pixel interpolating means 21 outputs the hologram data obtained by interpolating the missing pixels to the display means 22 .

The display means 22 displays the hologram data in which the missing pixels are interpolated by the missing pixel interpolating means 21 . Note that the data of the missing pixels does not depend on the input hologram data. Therefore, the defective pixel interpolating means 21 does not have to write the data of the defective pixels to the display means 22 every frame.
The display means 22 may consist of a spatial light modulator (SLM).
If the spatial light modulator is a reflective liquid crystal, the display means 22 reproduces a reproduced image by being irradiated with light emitted from the light emitting means 23 from the front as illumination light. If the spatial light modulator is a transmissive liquid crystal, the display means 22 reproduces a reproduced image by being irradiated with the light emitted by the light emitting means 23 from the back as the illumination light.

The light emitting means 23 irradiates the display means 22 with illumination light.
The light emitting means 23 includes, for example, a laser light emitting device as a light source and two convex lenses. to irradiate the display means 22.

As described above, the electronic holography display device 2 can interpolate the missing pixels of the missing hologram data and display a reproduced image.
The electronic holography display device 2 can be operated by an electronic holography display program for causing a computer (not shown) to function as each means described above.

[Operation of electronic holographic display device]
Next, the operation of the electronic holographic display device 2 according to the embodiment of the present invention will be described with reference to FIG. 6 (see also FIG. 5 for the configuration). It is assumed that missing data information for interpolating missing pixels of missing hologram data is stored in the missing data storage means 20 in advance.

In step S10, the missing pixel interpolating means 21 inputs the missing hologram data generated by the hologram data generating device 1 (see FIG. 1) through an input means (not shown).
In step S11, the missing pixel interpolating means 21 generates hologram data in which missing pixels are interpolated by inserting pixels into the missing hologram data at the positions of missing pixels stored in the missing data storage means 20. .
At step S12, the display means 22 displays the hologram data generated at step S11. At this time, the display means 22 displays the reproduced image by being irradiated with illumination light from the light emitting means 23 .
As a result, the electronic holography display device 2 can display a three-dimensional reconstructed image of the object from the missing hologram data.

(Regarding image quality due to missing pixels)
Here, the result of simulating the quality of a reproduced image by providing defective pixels in hologram data will be described.
Here, as subject data, an image of a mandrill published in a standard image database was simply used. The number of pixels of the display means 22 (SLM) to be displayed is 1024×1024 pixels. Since the image of the subject data is 512×512 pixels, it is made 1024×1024 pixels by padding the periphery with zeros. The display device 22 was a phase modulation type SLM. The number of gradations is 8 bits, and the pixel pitch is 1 μm both horizontally and vertically. A random phase was added as an initial phase. The initial phase was optimized by performing iterative calculation 50 times by the GS algorithm described later. A plane wave that vertically enters the display device 22 is used as the reference light.

The distance z between the object plane and the hologram plane (SLM) was set to z=Np/2 tan θ at which there is no error in the propagation calculation and the in-plane resolution of the reproduced image is the highest. Here, N is the number of pixels in one direction of the SLM (here, “1024”), p is the pixel pitch (here, “1”), θ is 1/2 of the viewing angle (θ=sin ⁻¹ [ λ/(2p)], where λ is the wavelength of light).

Under these conditions, hologram data was generated from the object data, and after part of the data was randomly lost (pixel value "0"), the object data was regenerated by performing backpropagation calculation. Then, the original subject data (original image) and the regenerated subject data (reproduced image) were compared and evaluated.
PSNR (maximum signal-to-noise ratio), which is an objective image quality evaluation index, was used to evaluate the image quality of the reproduced image. For image quality evaluation, other objective image quality evaluation index such as SSIM (Structural Similarity) or subjective evaluation experiment may be used.

FIG. 7 shows the simulation results. The horizontal axis of the graph in FIG. 7 indicates the ratio of defective pixels to all pixels (missing data amount [%]), and the vertical axis indicates PSNR (maximum signal-to-noise ratio [dB]). Here, the amount of missing data is set from 0.5% to 50%.
As shown in FIG. 7, the image quality (PSNR) deteriorates as the amount of missing data increases. This result will be the same if the ratio of the number of pixels of the SLM and the original image is the same.
Even if the hologram data is lost by the hologram data generation device 1, the reproduced image does not appear to have missing pixels, but the image quality of the entire image is affected.
Therefore, the hologram data generation device 1 can determine the amount of missing data within the range of image quality acceptable to the user. This makes it possible to reduce hologram data.

[Modification of hologram data generation device]
Next, a hologram data generation device 1B, which is a modified example of the hologram data generation device, will be described with reference to FIG.

The hologram data generation device 1B generates hologram data in which some pixels are missing from subject data, which is three-dimensional data, and is the same as the hologram data generation device 1 (see FIG. 1).
As shown in FIG. 8, the hologram data generation device 1B includes phase addition means 10, propagation calculation means 11B, hologram data calculation means 12, hologram data thinning means 13, and condition data storage means 14.
Since the configuration other than the propagation calculation means 11B is the same as that of the hologram data generation device 1 (see FIG. 1), the description is omitted.

The propagation calculation means 11B calculates a complex amplitude distribution of a predetermined hologram plane from the complex amplitude distribution of the subject data generated by the phase adding means 10 by propagation calculation.
The propagation calculation means 11 shown in FIG. 1 performs only one propagation calculation from the object plane to the hologram plane. On the other hand, the propagation calculation means 11B performs "propagation calculation" from the object plane to the hologram plane and "backpropagation calculation" from the hologram plane to the object plane by the GS (Gerchberg-Saxton) algorithm. Constraint conditions” (subject plane constraint conditions, hologram plane constraint conditions) are given and the process is repeated.

Propagation calculation means 11B performs propagation calculation according to the above equation (1), for example, on the complex amplitude distribution generated by phase addition means 10 to calculate the complex amplitude distribution on the hologram plane.
For example, when creating phase-modulated hologram data, the propagation calculation means 11B extracts only the phase of the complex amplitude distribution on the hologram plane as the hologram plane constraint condition. At this time, the propagation calculation means 11B gives a specific value (for example, "0") to pixels corresponding to missing pixels.
Then, the propagation calculation means 11B performs back propagation calculation corresponding to the above equation (1) for the phase distribution, and calculates the complex amplitude distribution on the object plane.
Then, the propagation calculation means 11B replaces the amplitude of the complex amplitude distribution on the object plane with the pixel value (amplitude) of the original object plane as the object plane constraint condition.

The propagation calculation means 11B can optimize the phase distribution by giving a constraint condition and repeating the propagation calculation and the backpropagation calculation by the GS algorithm.
The propagation calculation means 11B terminates the iterative calculation when the GS algorithm repeats the calculation a predetermined number of times (for example, 50 times) or when the amount of variation in the complex amplitude distribution on the hologram plane becomes equal to or less than a threshold. .
The propagation calculation means 11B outputs to the hologram data calculation means 12 the complex amplitude distribution on the hologram plane obtained by the GS algorithm.

Thus, the hologram data generation device 1B can generate hologram data with better image quality than the hologram data generation device 1B.
The defective hologram data generated by the hologram data generation device 1B can be reproduced as a three-dimensional object reproduction image by the electronic holography display device 2 (see FIG. 5).
The hologram data generation device 1B can operate a computer (not shown) with a hologram data generation program for functioning as each means described above.

The operation of this hologram data generation device 1B is different from the operation of step S3 of the hologram data generation device 1 described with reference to FIG. 4 only in that the GS algorithm is used, so description thereof will be omitted.

(Image quality using GS algorithm)
Here, the result of simulating the quality of a reproduced image by generating hologram data using the GS algorithm and providing defective pixels in the hologram data will be described.

FIG. 9 shows the simulation results. The horizontal axis of the graph in FIG. 9 indicates the ratio of defective pixels to all pixels (missing data amount [%]), and the vertical axis indicates PSNR (maximum signal-to-noise ratio [dB]). Various conditions such as subject data used are the same as in the simulation described with reference to FIG.
Comparing the result of FIG. 7 with the result of FIG. 9, the result of FIG. 9, that is, the use of the GS algorithm can suppress deterioration of image quality. For example, when the missing data amount is 25%, the image quality can be improved by about 4 dB by using the GS algorithm.

The configurations and operations of the hologram data generation devices 1 and 1B and the electronic holography display device 2 according to the embodiments of the present invention have been described above, but the present invention is not limited to these embodiments.
For example, here, tomographic images are used as object data, but point group data, polygon data, depth images, multi-viewpoint image groups, etc. may be used.
Also, in the examples of FIGS. 3A to 3D, the ratio of defective pixels (missing data amount) to the pixels of the entire hologram data HD is shown as an example of 25%. Any ratio may be used as long as the image quality deterioration of is within a range acceptable to the user.

Reference Signs List 1, 1B hologram data generation device 10 phase addition means 11, 11B propagation calculation means 12 hologram data calculation means 13 hologram data thinning means 14 condition data storage means 2 electronic holography display device 20 missing data storage means 21 missing pixel interpolation means 22 display means (spatial light modulator)
23 luminous means

Claims (7)

A hologram data generation device for generating hologram data in which some pixels are missing from subject data, which is three-dimensional data,
phase addition means for adding a phase to the object data to generate a complex amplitude distribution;
Propagation calculation means for calculating a complex amplitude distribution of the hologram plane from the complex amplitude distribution of the subject data by propagation calculation;
hologram data calculation means for calculating hologram data from the complex amplitude distribution of the hologram plane and the complex amplitude distribution of the reference light;
hologram data thinning means for thinning data at preset defective pixel positions from the hologram data calculated by the hologram data calculating means;
A hologram data generation device comprising: 2. The hologram data generating apparatus according to claim 1, wherein said hologram data thinning means thins out data as said missing pixel positions from said hologram data for each row, each column, each block, or randomly. 3. The hologram data generation apparatus according to claim 1, wherein said propagation calculation means calculates the complex amplitude distribution of said hologram plane by a GS algorithm. A hologram data generation program for causing a computer to function as the hologram data generation device according to any one of claims 1 to 3. An electronic holography display device for inputting missing hologram data in which a part of a pixel is missing and displaying a reproduced image of a subject,
defective pixel interpolation means for interpolating pixels into defective pixels of the defective hologram data;
display means comprising a spatial light modulator for displaying hologram data in which the defective pixels are interpolated by the defective pixel interpolating means;
light emitting means for irradiating the spatial light modulator with illumination light;
An electronic holographic display device comprising: 6. The electronic holographic display device according to claim 5, wherein said defective pixel interpolating means does not write data of defective pixels of said hologram data to said spatial light modulator. An electronic holography display program for causing a computer to function as the electronic holography display device according to claim 5 or 6.

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