CN116184798A - Encoding method and system for generating three-phase hologram - Google Patents

Encoding method and system for generating three-phase hologram Download PDF

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CN116184798A
CN116184798A CN202310206050.4A CN202310206050A CN116184798A CN 116184798 A CN116184798 A CN 116184798A CN 202310206050 A CN202310206050 A CN 202310206050A CN 116184798 A CN116184798 A CN 116184798A
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complex amplitude
phase
diffraction field
original image
unit
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闫兴鹏
刘新蕾
李佳琦
胡海荣
荆涛
蒋晓瑜
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Academy of Armored Forces of PLA
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    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T9/00—Image coding
    • G06T9/002—Image coding using neural networks
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
    • G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
    • G03H1/04—Processes or apparatus for producing holograms
    • G03H1/08—Synthesising holograms, i.e. holograms synthesized from objects or objects from holograms
    • G03H1/0841—Encoding method mapping the synthesized field into a restricted set of values representative of the modulator parameters, e.g. detour phase coding
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
    • G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
    • G03H1/04—Processes or apparatus for producing holograms
    • G03H1/16—Processes or apparatus for producing holograms using Fourier transform
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06N—COMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS
    • G06N3/00—Computing arrangements based on biological models
    • G06N3/02—Neural networks
    • G06N3/08—Learning methods
    • G06N3/084—Backpropagation, e.g. using gradient descent
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T17/00—Three dimensional [3D] modelling, e.g. data description of 3D objects
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
    • G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
    • G03H1/04—Processes or apparatus for producing holograms
    • G03H1/08—Synthesising holograms, i.e. holograms synthesized from objects or objects from holograms
    • G03H1/0841—Encoding method mapping the synthesized field into a restricted set of values representative of the modulator parameters, e.g. detour phase coding
    • G03H2001/085—Kinoform, i.e. phase only encoding wherein the computed field is processed into a distribution of phase differences

Abstract

The invention discloses a coding method and a system for generating a three-phase hologram, which relate to the field of coding, and the method comprises the following steps: obtaining an initial complex amplitude of a diffraction field in the back propagation process of an original image based on the Fourier transform and an optical transfer function in the back propagation process; sequentially carrying out normalization, complex exponential form representation and square opening on the initial complex amplitude of the diffraction field to obtain the complex amplitude of the diffraction field; decomposing the complex amplitude of the diffraction field according to a vector addition principle to obtain a first unit complex amplitude and a second unit complex amplitude; constructing cross-coded first, second and third phases based on the complex amplitude of the diffraction field, the first unit complex amplitude and the second unit complex amplitude; and performing cross coding based on the first phase, the second phase and the third phase to obtain a three-phase hologram. The invention improves the display quality of the reconstructed image on the premise of not reducing the double-phase encoding speed basically.

Description

Encoding method and system for generating three-phase hologram
Technical Field
The invention relates to the field of coding, in particular to a coding method and a coding system for generating a three-phase hologram.
Background
The computer generated hologram (Computer generated holography, CGH) combines computer technology with optical holography to realize some functions which are difficult or impossible to realize by optical holography, such as controlling the size of the reconstructed object or reconstructing the object which is not present in reality. Devices replacing photosensitive materials in optical holography are mainly Spatial light modulators (Spatial LightModulator, SLM), whereas current SLMs are mainly phase type, which can modulate only the phase of the incident light and not the amplitude. How to generate corresponding phase-only information from the diffraction field information has become a major issue in computing holograms. Conventional generation methods include iterative-based (Gerchberg-Saxton, GS) algorithm and (Wirtinger Holography, WH) algorithm, one-step coding (Double-phase Holography, DPH) algorithm and (Stochastic Gradient Descent, SGD) algorithm.
The bi-phase encoding method represents one complex amplitude as the sum of two unit complex amplitudes through the phase decomposition principle of the complex amplitude, but because the complex amplitude loses excessive phase information in the process of cross encoding, a great amount of space shift noise is inevitably generated in a reconstructed image, which damages the details of the reconstructed image and reduces the reconstruction quality and definition.
Disclosure of Invention
The invention aims to provide a coding method and a coding system for generating a three-phase hologram, which can improve the display quality of a reconstructed image on the premise of basically not reducing the double-phase coding speed.
In order to achieve the above object, the present invention provides the following solutions:
an encoding method for generating a three-phase hologram, comprising:
obtaining an initial complex amplitude of a diffraction field in the back propagation process of an original image based on the Fourier transform and an optical transfer function in the back propagation process;
sequentially carrying out normalization, complex exponential form representation and square opening on the initial complex amplitude of the diffraction field to obtain the complex amplitude of the diffraction field;
decomposing the complex amplitude of the diffraction field according to a vector addition principle to obtain a first unit complex amplitude and a second unit complex amplitude;
constructing cross-coded first, second and third phases based on the complex amplitude of the diffraction field, the first unit complex amplitude and the second unit complex amplitude;
and performing cross coding based on the first phase, the second phase and the third phase to obtain a three-phase hologram.
Preferably, the obtaining the initial complex amplitude of the diffraction field in the back propagation of the original image based on the fourier transform and the optical transfer function in the back propagation includes:
obtaining a complex amplitude of the original image based on the intensity of the original image; performing fast Fourier transform on the complex amplitude of the original image to obtain a frequency spectrum of the original image;
constructing the optical transfer function in a back propagation process;
multiplying the spectrum of the original image with the optical transfer function to obtain the spectrum of the diffraction field in the back propagation process of the original image;
and carrying out inverse Fourier transform on the frequency spectrum of the diffraction field to obtain the initial complex amplitude of the diffraction field in the back propagation process of the original image.
Preferably, the normalizing, the complex exponential representation and the square-opening are sequentially performed on the initial complex amplitude of the diffraction field to obtain a complex amplitude of the diffraction field, including:
normalizing the initial complex amplitude of the diffraction field, and mapping the initial complex amplitude to a [0,1] interval to obtain a normalized diffraction field;
the normalized diffraction field is expressed in a complex exponential form, and a complex exponential diffraction field is obtained;
and squaring the complex index diffraction field to obtain the complex amplitude of the diffraction field.
Preferably, the cross coding mode is as follows:
the upper left corner of the adjacent square phase fills the first phase, the lower right corner of the adjacent square phase fills the second phase, the lower left corner of the adjacent square phase and the upper right corner of the adjacent square phase fill the third phase.
The present invention provides an encoding system for generating a three-phase hologram, comprising:
the complex amplitude module is used for obtaining the initial complex amplitude of the diffraction field in the back propagation process of the original image based on the Fourier transform and the optical transfer function in the back propagation process;
the processing module is used for sequentially carrying out normalization, complex exponential form representation and square opening on the initial complex amplitude of the diffraction field to obtain the complex amplitude of the diffraction field;
the decomposition module is used for decomposing the complex amplitude of the diffraction field according to the vector addition principle to obtain a first unit complex amplitude and a second unit complex amplitude;
a phase module for constructing a cross-coded first phase, a second phase, and a third phase based on the complex amplitude of the diffraction field, the first unit complex amplitude, and the second unit complex amplitude;
and the encoding module is used for performing cross encoding based on the first phase, the second phase and the third phase to obtain a three-phase hologram.
Preferably, the complex amplitude module includes:
the frequency spectrum unit is used for obtaining the complex amplitude of the original image based on the intensity of the original image, and performing fast Fourier transform on the complex amplitude of the original image to obtain the frequency spectrum of the original image;
a function unit for constructing the optical transfer function in the back propagation process;
the multiplication unit is used for multiplying the frequency spectrum of the original image and the optical transfer function to obtain the frequency spectrum of the diffraction field in the back propagation process of the original image;
and the complex amplitude unit is used for carrying out inverse Fourier transform on the frequency spectrum of the diffraction field to obtain the initial complex amplitude of the diffraction field in the process of back propagation of the original image.
Preferably, the processing module includes:
the normalization unit is used for normalizing the initial complex amplitude of the diffraction field and mapping the initial complex amplitude to a [0,1] interval to obtain a normalized diffraction field;
the complex index unit is used for representing the normalized diffraction field in a complex index form to obtain a complex index diffraction field;
and the open square unit is used for carrying out open square on the complex index diffraction field to obtain the complex amplitude of the diffraction field.
Preferably, the cross coding mode is as follows:
the upper left corner of the adjacent square phase fills the first phase, the lower right corner of the adjacent square phase fills the second phase, the lower left corner of the adjacent square phase and the upper right corner of the adjacent square phase fill the third phase.
According to the specific embodiment provided by the invention, the invention discloses the following technical effects:
1) The coding speed is high: compared with the traditional phase recovery algorithm (such as GS algorithm and WH algorithm) based on the iterative thought, the three-phase encoding mode encodes complex amplitude in a pixel-by-pixel mode, all operations belong to matrix operation, and CUDA can be used for acceleration, so that the method has very high calculation speed.
2) The method comprises the following steps of: the three-phase encoding mode is used for representing one more phase of information than the traditional double-phase encoding mode, so that the information is more useful, and the reconstructed target image has higher display quality and definition.
3) The phase structure has periodicity: the pure phase hologram generated by the three-phase encoding mode has a good periodic phase structure, can form regular diffraction order distribution, and eliminates speckle noise in a reconstructed image.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the drawings that are needed in the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a flow chart of an encoding method for generating a three-phase hologram according to the present invention;
FIG. 2 is a block diagram of an encoding system for generating a three-phase hologram according to the present invention;
FIG. 3 is a schematic spectrum of an original image according to the present invention;
FIG. 4 is a schematic diagram of the spectrum of the diffraction field of the present invention;
FIG. 5 is a schematic representation of the initial complex amplitude of the diffraction field of the present invention;
FIG. 6 is a diagram of normalized diffraction fields and complex index diffraction fields of the present invention;
FIG. 7 is a schematic representation of the complex amplitude decomposition of the diffraction field of the present invention.
FIG. 8 is a schematic diagram of a cross-stitch pattern according to the present invention.
Symbol description: 1. a complex amplitude module; 2. a processing module; 3. a decomposition module; 4. a phase module; 5. and a coding module.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The invention aims to provide a coding method and a coding system for generating a three-phase hologram, which can improve the display quality of a reconstructed image on the premise of basically not reducing the double-phase coding speed.
In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention will be rendered by reference to the appended drawings and appended detailed description.
FIG. 1 is a flow chart of an encoding method for generating a three-phase hologram according to the present invention. As shown in fig. 1, the present invention provides an encoding method for generating a three-phase hologram, comprising:
step S1, obtaining initial complex amplitude of diffraction field in the original image back propagation process based on Fourier transformation and optical transfer function in the back propagation process.
Specifically, the step S1 includes:
step S11, obtaining complex amplitude of the original image based on the intensity of the original image; and performing fast Fourier transform on the complex amplitude of the original image to obtain a frequency spectrum of the original image. The spectrum of the original image is shown in fig. 3.
Setting initial phases to be 0, wherein the complex amplitude of the original image is as follows:
Figure BDA0004115110150000051
wherein: u (U) 0 (x, y) is the complex amplitude of the original image, I (x, y) is the intensity of the original image, x is the x-axis coordinate, y is the y-axis coordinate, j is the imaginary unit, j 2 ＝-1。
The spectrum of the original image is as follows:
Figure BDA0004115110150000052
wherein: t (T) 0 (f x ，f y ) For the spectrum of the original image, f x Spatial frequency of complex amplitude distribution in x-direction for original image, f y For the spatial frequency of the complex amplitude distribution of the original image in the y-direction,
Figure BDA0004115110150000053
is a fourier transform.
Step S12, constructing the optical transfer function in the back propagation process.
The optical transfer function is as follows:
Figure BDA0004115110150000054
wherein: h F (f x ，f y ) Z is the imaging distance and λ is the wavelength of monochromatic light, which is the optical transfer function.
And step S13, multiplying the spectrum of the original image and the optical transfer function to obtain the spectrum of the diffraction field in the back propagation process of the original image. The spectrum of the diffraction field is shown in fig. 4.
The spectrum of the diffraction field is as follows:
T(f x ,f y )＝T 0 (f x ,f y )·H F (f x ,f y )。
and step S14, carrying out inverse Fourier transform on the frequency spectrum of the diffraction field to obtain the initial complex amplitude of the diffraction field in the process of back propagation of the original image. The initial complex amplitude of the diffraction field is shown in fig. 5. The initial complex amplitude of the diffraction field is as follows:
Figure BDA0004115110150000061
wherein:
Figure BDA0004115110150000062
is an inverse fourier transform.
And S2, sequentially carrying out normalization, complex exponential form representation and square opening on the initial complex amplitude of the diffraction field to obtain the complex amplitude of the diffraction field.
Preferably, the step S2 includes:
and S21, normalizing the initial complex amplitude of the diffraction field, and mapping the initial complex amplitude to a [0,1] interval to obtain a normalized diffraction field. The normalization formula is as follows:
Figure BDA0004115110150000063
wherein: u' (x, y) is the normalized diffraction field.
And S22, representing the normalized diffraction field in a complex exponential form to obtain a complex exponential diffraction field. The complex index diffraction field has the following formula:
Figure BDA0004115110150000064
wherein: a (x, y) is the amplitude of the normalized diffraction field,
Figure BDA0004115110150000065
is the phase of the normalized diffraction field. />
The normalized diffraction field and the complex index diffraction field are shown in fig. 6.
And S23, performing open square on the complex index diffraction field to obtain complex amplitude of the diffraction field. The complex amplitude of the diffraction field is as follows:
Figure BDA0004115110150000066
wherein:
Figure BDA0004115110150000067
and step S3, decomposing the complex amplitude of the diffraction field according to a vector addition principle to obtain a first unit complex amplitude and a second unit complex amplitude.
Specifically, as shown in fig. 7, the decomposition formula is as follows:
Figure BDA0004115110150000068
wherein: θ 1 (x, y) is the first unit complex amplitude, θ 2 (x, y) is the second unit complex amplitude.
θ 1 (x, y) and θ 2 (x, y) needs to satisfy the following formula:
Figure BDA0004115110150000071
the method can obtain:
Figure BDA0004115110150000072
and S4, constructing a first phase, a second phase and a third phase of cross coding based on the complex amplitude of the diffraction field, the first unit complex amplitude and the second unit complex amplitude.
Based on the complex exponential diffraction field, the complex amplitude of the diffraction field, the first unit complex amplitude, and the second unit complex amplitude, the method comprises:
Figure BDA0004115110150000073
the simplification is obtained:
Figure BDA0004115110150000074
wherein: phi (phi) 1 (x, y) is the first phase, phi 2 (x, y) is the second phase, phi 3 (x, y) is the third phase.
And S5, performing cross coding based on the first phase, the second phase and the third phase to obtain a three-phase hologram.
Specifically, as shown in fig. 8:
the cross coding mode is as follows:
the upper left corner of the adjacent square phase fills the first phase, the lower right corner of the adjacent square phase fills the second phase, the lower left corner of the adjacent square phase and the upper right corner of the adjacent square phase fill the third phase.
Fig. 2 is a block diagram of an encoding system for generating a three-phase hologram according to the present invention. As shown in fig. 2, the present invention provides an encoding system for generating a three-phase hologram, comprising: complex amplitude module 1, processing module 2, decomposition module 3, phase module 4 and encoding module 5.
The complex amplitude module 1 is used for obtaining the initial complex amplitude of the diffraction field in the back propagation process of the original image based on the Fourier transform and the optical transfer function in the back propagation process.
The processing module 2 is configured to normalize, represent in a complex exponential form, and square open in order the initial complex amplitude of the diffraction field, so as to obtain a complex amplitude of the diffraction field.
The decomposition module 3 is configured to decompose the complex amplitude of the diffraction field according to a vector addition principle, so as to obtain a first unit complex amplitude and a second unit complex amplitude.
The phase module 4 is configured to construct a cross-coded first phase, a second phase and a third phase based on the complex amplitude of the diffraction field, the first unit complex amplitude and the second unit complex amplitude.
The encoding module 5 is configured to perform cross encoding based on the first phase, the second phase and the third phase to obtain a three-phase hologram.
Optionally, the complex amplitude module 1 includes: spectrum unit, function unit, multiplication unit and complex amplitude unit.
The frequency spectrum unit is used for obtaining the complex amplitude of the original image based on the intensity of the original image, and performing fast Fourier transform on the complex amplitude of the original image to obtain the frequency spectrum of the original image.
The function unit is used for constructing the optical transfer function in the back propagation process.
The multiplication unit is used for multiplying the spectrum of the original image and the optical transfer function to obtain the spectrum of the diffraction field in the back propagation process of the original image.
The complex amplitude unit is used for carrying out inverse Fourier transform on the frequency spectrum of the diffraction field to obtain the initial complex amplitude of the diffraction field in the process of back propagation of the original image.
Optionally, the processing module 2 includes: normalization unit, complex exponential unit and open square unit.
The normalization unit is used for normalizing the initial complex amplitude of the diffraction field and mapping the initial complex amplitude to a [0,1] interval to obtain a normalized diffraction field.
The complex index unit is used for representing the normalized diffraction field in a complex index form to obtain a complex index diffraction field.
The open square unit is used for carrying out open square on the complex index diffraction field to obtain complex amplitude of the diffraction field.
Optionally, the cross coding mode is as follows:
the upper left corner of the adjacent square phase fills the first phase, the lower right corner of the adjacent square phase fills the second phase, the lower left corner of the adjacent square phase and the upper right corner of the adjacent square phase fill the third phase.
In the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant points refer to the description of the method section.
The principles and embodiments of the present invention have been described herein with reference to specific examples, the description of which is intended only to assist in understanding the methods of the present invention and the core ideas thereof; also, it is within the scope of the present invention to be modified by those of ordinary skill in the art in light of the present teachings. In view of the foregoing, this description should not be construed as limiting the invention.

Claims (8)

1. A coding method for generating a three-phase hologram, comprising:
obtaining an initial complex amplitude of a diffraction field in the back propagation process of an original image based on the Fourier transform and an optical transfer function in the back propagation process;
sequentially carrying out normalization, complex exponential form representation and square opening on the initial complex amplitude of the diffraction field to obtain the complex amplitude of the diffraction field;
decomposing the complex amplitude of the diffraction field according to a vector addition principle to obtain a first unit complex amplitude and a second unit complex amplitude;
constructing cross-coded first, second and third phases based on the complex amplitude of the diffraction field, the first unit complex amplitude and the second unit complex amplitude;
and performing cross coding based on the first phase, the second phase and the third phase to obtain a three-phase hologram.
2. The encoding method for generating a three-phase hologram according to claim 1, wherein the obtaining an initial complex amplitude of a diffraction field during back propagation of an original image based on fourier transform and an optical transfer function during back propagation comprises:
obtaining a complex amplitude of the original image based on the intensity of the original image; performing fast Fourier transform on the complex amplitude of the original image to obtain a frequency spectrum of the original image;
constructing the optical transfer function in a back propagation process;
multiplying the spectrum of the original image with the optical transfer function to obtain the spectrum of the diffraction field in the back propagation process of the original image;
and carrying out inverse Fourier transform on the frequency spectrum of the diffraction field to obtain the initial complex amplitude of the diffraction field in the back propagation process of the original image.
3. The method of claim 1, wherein normalizing, complex exponential representation and squaring the initial complex amplitude of the diffraction field to obtain a complex amplitude of the diffraction field comprises:
normalizing the initial complex amplitude of the diffraction field, and mapping the initial complex amplitude to a [0,1] interval to obtain a normalized diffraction field;
the normalized diffraction field is expressed in a complex exponential form, and a complex exponential diffraction field is obtained;
and squaring the complex index diffraction field to obtain the complex amplitude of the diffraction field.
4. The encoding method for generating a three-phase hologram according to claim 1, wherein the cross-encoding is performed by:
the upper left corner of the adjacent square phase fills the first phase, the lower right corner of the adjacent square phase fills the second phase, the lower left corner of the adjacent square phase and the upper right corner of the adjacent square phase fill the third phase.
5. A coding system for generating a three-phase hologram, comprising:
the complex amplitude module is used for obtaining the initial complex amplitude of the diffraction field in the back propagation process of the original image based on the Fourier transform and the optical transfer function in the back propagation process;
the processing module is used for sequentially carrying out normalization, complex exponential form representation and square opening on the initial complex amplitude of the diffraction field to obtain the complex amplitude of the diffraction field;
the decomposition module is used for decomposing the complex amplitude of the diffraction field according to the vector addition principle to obtain a first unit complex amplitude and a second unit complex amplitude;
a phase module for constructing a cross-coded first phase, a second phase, and a third phase based on the complex amplitude of the diffraction field, the first unit complex amplitude, and the second unit complex amplitude;
and the encoding module is used for performing cross encoding based on the first phase, the second phase and the third phase to obtain a three-phase hologram.
6. The encoding system for generating a three-phase hologram according to claim 5, wherein said complex amplitude module comprises:
the frequency spectrum unit is used for obtaining the complex amplitude of the original image based on the intensity of the original image, and performing fast Fourier transform on the complex amplitude of the original image to obtain the frequency spectrum of the original image;
a function unit for constructing the optical transfer function in the back propagation process;
the multiplication unit is used for multiplying the frequency spectrum of the original image and the optical transfer function to obtain the frequency spectrum of the diffraction field in the back propagation process of the original image;
and the complex amplitude unit is used for carrying out inverse Fourier transform on the frequency spectrum of the diffraction field to obtain the initial complex amplitude of the diffraction field in the process of back propagation of the original image.
7. The encoding system for generating a three-phase hologram according to claim 5, wherein said processing module comprises:
the normalization unit is used for normalizing the initial complex amplitude of the diffraction field and mapping the initial complex amplitude to a [0,1] interval to obtain a normalized diffraction field;
the complex index unit is used for representing the normalized diffraction field in a complex index form to obtain a complex index diffraction field;
and the open square unit is used for carrying out open square on the complex index diffraction field to obtain the complex amplitude of the diffraction field.
8. The encoding system for generating a three-phase hologram according to claim 5, wherein said cross-encoding is performed by:
the upper left corner of the adjacent square phase fills the first phase, the lower right corner of the adjacent square phase fills the second phase, the lower left corner of the adjacent square phase and the upper right corner of the adjacent square phase fill the third phase.
CN202310206050.4A 2023-02-27 2023-02-27 Encoding method and system for generating three-phase hologram Pending CN116184798A (en)

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