Optical multiplexed holographic display device and method based on optical coherence encoding

Abstract

The application discloses an optical multiplexing holographic display device and method based on optical coherence coding. f The device is composed of a laser, a beam expander, a spatial light modulator, a fourth lens, a digital micromirror device, a third lens, a charge coupled device and a computer. Orthogonal storage channels are generated through coherence coding. Information reading is completed through conjugate decryption combined with Fourier transform after orthogonal physical degree encryption, optical multiplexing and dynamic ensemble average processing. The optical coherence coding is introduced into the optical multiplexing holographic system, and the orthogonal physical degree encryption and the dynamic ensemble average processing are combined, so that the problems of inter-channel crosstalk, intra-channel crosstalk, speckle noise, artifacts and the like in the traditional optical multiplexing holographic system are improved from the root, and the number of coded channels, the information capacity of a single channel and the information reading fidelity are significantly improved.

Description

Technical Field

[0001] This invention relates to the field of optical element technology, and in particular to an optical multiplexing holographic display device and method based on optical coherent coding. Background Technology

[0002] With the popularization of optical modulation devices such as spatial light modulators and digital micromirror devices, optical multiplexing holography based on the physical degree of freedom of light field manipulation has developed rapidly. It realizes parallel encoding and multiplexing of multi-channel information through orthogonal physical quantities such as orbital angular momentum, wavelength, and polarization, which greatly improves the carrying capacity of optical information.

[0003] However, in the practical application of existing optical multiplexing holographic systems and display devices, the following problems exist: there is significant crosstalk between different information storage channels and between adjacent pixels in the same channel. At the same time, speckle noise, artifacts and other interference are easily generated during high coherence light transmission and modulation, which directly leads to a sharp reduction in the number of usable coding channels and a limitation on the information capacity of a single channel, which greatly reduces the signal-to-noise ratio and information reading accuracy of holographic displays.

[0004] Existing optical multiplexing systems mostly focus on the coding design of a single physical degree of freedom, without incorporating the control of optical field coherence into the multiplexing technology. Although studies have confirmed that optical coherence control can effectively suppress negative effects such as crosstalk and speckle in imaging and transmission, there is currently a lack of complete optical devices that combine optical coherence coding with optical multiplexing holography, and there is also a lack of standardized multiplexing, encryption, decryption, and display methods. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an optical multiplexing holographic display device and method based on optical coherent coding.

[0006] On one hand, an optical multiplexing holographic display device based on optical coherent coding is provided, comprising: a laser, a first beam expander, a first beam splitter, a spatial light modulator, and 4... connected in sequence. f The system includes a filter module, a second beam splitter, a digital micromirror device, a third lens, a charge-coupled device, and a computer. The computer is connected to the spatial light modulator, the digital micromirror device, and the charge-coupled device, respectively, and controls the loading of the computational hologram on the spatial light modulator and the loading of the dynamic optical multiplexing hologram on the digital micromirror device, as well as controlling the charge-coupled device to capture light intensity information.

[0007] Furthermore, a spatial light modulator loads a computer-generated computational hologram; the mathematical form of the computational hologram is expressed as:

[0008] in, Indicates the use of decryption of the first j The decryption information of the target information of each storage channel is provided by N Determined by a number of distinct and mutually orthogonal physical degrees of freedom; Indicates the first j The decryption information corresponding to the storage channel contains the first... i Encrypted information provided by each physical degree of freedom i ={1,2,..., N}

[0009] Furthermore, the digital micromirror device loads and loops a computer-generated dynamic optical multiplexing hologram, wherein the steps of generating the computer-generated dynamic optical multiplexing hologram include: Optical coherence encoding is performed on multiple target information to generate multiple corresponding target information storage channels; By introducing one or more additional orthogonal physical degrees of freedom to encrypt the aforementioned target information storage channel, multiple corresponding encrypted holograms are obtained. Optical multiplexing of multiple encrypted holograms; Repeat the above steps several times to obtain multiple dynamic optical multiplexing holograms that are different but have specific optical coherence statistical properties.

[0010] Furthermore, the step of optically coherently encoding multiple target information to generate multiple corresponding target information storage channels can be mathematically expressed as follows:

[0011] in Indicates the first k The first dynamic optical multiplexing hologram The storage channel generated after optical coherence encoding of target information r Spatial location coordinates, The non-negative pattern weights. ; Represents the position in frequency space coordinates Intensity distribution of target information; This represents a square-integrable kernel. , The electric field distribution of the light source, c Let it be a set constant; It is represented as a uniform random process.

[0012] Furthermore, the mathematical expression for the step of introducing one or more additional orthogonal physical degrees of freedom to encrypt and encode the aforementioned target information storage channel to obtain multiple corresponding encrypted holograms is as follows:

[0013] in, Indicates the encrypted first... l The encrypted hologram of each storage channel, whose encrypted information is provided by N Determined by a number of distinct and mutually orthogonal physical degrees of freedom; Indicates the first l The encrypted information corresponding to the storage channel is composed of the first... i Encrypted information provided by each physical degree of freedom i ={1,2,..., N}

[0014] Furthermore, the mathematical expression for the optical multiplexing operation on multiple encrypted holograms is as follows:

[0015] in, Indicates the first one used for loading k Zhang dynamic optical multiplexed hologram.

[0016] Furthermore, the third lens is used to perform a Fourier transform operation on the decrypted multi-channel mixed optical information emitted from the digital micromirror device. The Fourier transform operation performed on the decrypted multi-channel hybrid optical information is expressed as follows:

[0017] in Indicates the first k After decrypting the dynamic optical multiplexed hologram, the light field information of the far-field observation plane is obtained. FT This is a two-dimensional discrete Fourier transform operation. Indicates the use of decryption of the first j Decryption information for target information in each storage channel Indicates the first one used for loading k Zhang dynamic optical multiplexed hologram Indicates the first j The decryption information corresponding to the storage channel contains the first... i The decryption information provided by each physical degree of freedom i ={1,2,..., N}; Indicates the first l The encrypted information corresponding to the storage channel is composed of the first... i Encrypted information provided by each physical degree of freedom i ={1,2,..., N}; Indicates the first k The first dynamic optical multiplexing hologram The storage channel is generated after the target information is optically coherently encoded; Indicates from the first k The decrypted first hologram of dynamic optical multiplexing j The light field information of the target information in each storage channel, " is the symbol for convolution operation.

[0018] Furthermore, the charge-coupled device (CCD) records the multi-channel mixed optical intensity information after Fourier transform; each storage channel has good orthogonality, therefore, the total far-field light intensity has a linear relationship with the intensity of each storage channel, and its mathematical expression is:

[0019] in Indicates the total light intensity in the far field; Indicates from the first k The decrypted first hologram of dynamic optical multiplexing j Intensity information of the target information in each storage channel; Indicates the first k After decrypting the dynamic optical multiplexed hologram, the light field information of the far-field observation plane is obtained. Indicates from the first k The decrypted first hologram of dynamic optical multiplexing j The optical field information of the target information of each storage channel FT This is a two-dimensional discrete Fourier transform operation. Indicates the first j The decryption information corresponding to the storage channel contains the first... i The decryption information provided by each physical degree of freedom i ={1,2,..., N}; Indicates the first l The encrypted information corresponding to the storage channel is composed of the first... i Encrypted information provided by each physical degree of freedom i ={1,2,..., N}; Indicates the first k The first dynamic optical multiplexing hologram The storage channel is generated after the target information is optically coherently encoded.

[0020] Furthermore, superimposed K After the dynamic optical multiplexing hologram is generated, the charge-coupled device records the multi-channel mixed optical intensity information after ensemble averaging. Its mathematical expression is:

[0021] in This represents multi-channel mixed optical intensity information. Indicates the decrypted first... j The light intensity information after ensemble averaging of each storage channel, i.e., the information to be read, is represented by "<>". The "<>" indicates ensemble averaging, and the ensemble averaging term on the right... I BN Background light intensity, i.e., background noise, is generated due to the mismatch between the decrypted information and the remaining physical degrees of freedom of the encrypted storage channel. I BN The intensity is negligible and does not affect the light intensity information. Reading.

[0022] On the other hand, an optical multiplexing holographic display method based on optical coherent coding is provided, comprising: using the apparatus described in the first aspect above, The laser beam generated in the laser is magnified by the first beam expander and then enters the spatial light modulator through the first beam splitter, where a computer-generated computational hologram containing specific decryption information is loaded. The beam then reflects from the spatial light modulator into 4 f In the filtering module, the filtered outgoing light passes through the second beam splitter and is incident on the digital micromirror device, on which a dynamic optical multiplexing hologram generated by a computer is played in a loop. Subsequently, the beam is reflected and passes through the third lens to complete its Fourier transform operation; on the back focal plane of the third lens, the multi-channel mixed optical intensity information after Fourier transform is recorded by a computer-controlled charge-coupled device.

[0023] The above technical solution has the following advantages or beneficial effects: This disclosure provides an optical multiplexing holographic display device and method based on optical coherence coding. By introducing optical coherence coding into the optical multiplexing holographic system and combining orthogonal physical degree of freedom encryption and dynamic ensemble averaging processing, it fundamentally improves the problems of crosstalk between channels and within channels, as well as speckle noise and artifacts in traditional optical multiplexing holography, and significantly improves the number of coding channels, single-channel information capacity and information reading fidelity. Attached Figure Description

[0024] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0025] Figure 1 This is a schematic diagram of an optical multiplexing holographic display device based on optical coherence coding as described in Embodiment 1; Figure 2 The target information used in different storage channels as described in Example 1; Figure 3The computational hologram containing specific decryption information is loaded onto the spatial light modulator obtained in Example 1; Figure 4 The image is a dynamic optical multiplexed hologram that is played in a loop on the digital micromirror device described in Example 1. Figure 5 This refers to the strength information after decryption and ensemble averaging of different storage channels as described in Example 1.

[0026] Among them, 1. Laser, 2. First beam expander, 3. First beam splitter, 4. Spatial light modulator, 5. First lens, 6. Aperture, 7. Second lens, 8. Second beam splitter, 9. Digital micromirror device, 10. Third lens, 11. Charge-coupled device, 12. Computer. Detailed Implementation

[0027] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0028] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the invention. The terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0029] In this embodiment of the invention, "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Furthermore, in the description of this invention, "multiple" refers to two or more.

[0030] Furthermore, to facilitate a clear description of the technical solutions of the embodiments of the present invention, the terms "first" and "second" are used in the embodiments of the present invention to distinguish identical or similar items with essentially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and the terms "first" and "second" are not necessarily different.

[0031] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0032] All data acquisition in this embodiment is carried out in accordance with laws and regulations and with user consent, and the data is used legally.

[0033] Example 1 This embodiment provides an optical multiplexing holographic display device based on optical coherent coding, such as... Figure 1 As shown, it includes: a laser 1, a first beam expander 2, a first beam splitter 3, and a spatial light modulator 4, connected in sequence. f The filter module, the second beam splitter 8, the digital micromirror device 9, the third lens 10, the charge-coupled device 11, and the computer 12; The computer 12 is connected to the spatial light modulator 4, the digital micromirror device 9 and the charge-coupled device 11 respectively, and controls the loading of the computational hologram on the spatial light modulator 4 and the loading of the dynamic optical multiplexing hologram on the digital micromirror device 9, as well as controlling the charge-coupled device 11 to capture light intensity information.

[0034] Among them, laser 1 is a solid-state continuous laser with an emission wavelength of 532nm; The first beam expander 2 is used to expand the laser beam emitted by the laser, and the size of the expanded beam spot needs to cover the subsequent computational hologram. The first beam splitter 3 is used to assist the incident laser after beam expansion in acquiring the optical information loaded on the subsequent spatial light modulator 4; Spatial light modulator 4 loads a computational hologram generated by computer 12; the mathematical form of the computational hologram is expressed as: (1) in, Indicates the use of decryption of the first j The decryption information of the target information of each storage channel is provided by N Determined by a number of distinct and mutually orthogonal physical degrees of freedom; Indicates the first j The decryption information corresponding to the storage channel contains the first... i The decryption information provided by each physical degree of freedom i ={1,2,..., N}

[0035] In one embodiment, the mathematical form for calculating the hologram is expressed as follows:

[0036] in, These are angular coordinates in the polar coordinate system. The topological charge is The optical orbital angular momentum is used to decipher the first... j The target information for each storage channel.

[0037] The 4 fThe filtering module includes a first lens 5, an aperture 6, and a second lens 7, wherein the first lens 5 is used to form a 4 f The front lens of the filtering system. Aperture 6, used to achieve spatial filtering, can filter out the +1 diffraction order of the light emitted from the spatial light modulator 4. Second lens 7, used to form 4... f The rear lens of the filtering system.

[0038] The second beam splitter 8 is used to assist the +1st stage output light after spatial filtering in acquiring the optical information loaded on the subsequent digital micromirror device 9.

[0039] The digital micromirror device 9 loads and loops a dynamic optical multiplexed hologram. The dynamic optical multiplexed hologram loaded and looped on the digital micromirror device 9 is generated by the computer 12.

[0040] In one embodiment, the steps of computer 12 generating a dynamic optical multiplexed hologram are as follows: S11: Optical coherence encoding is performed on multiple target information to generate multiple corresponding target information storage channels; The mathematical expression for the steps of optically coherently encoding multiple target information to generate multiple corresponding target information storage channels is as follows: (2) in Indicates the first k The first dynamic optical multiplexing hologram The storage channel generated after the target information is optically coherently encoded. r Spatial location coordinates, The non-negative pattern weights. , Represents the position in frequency space coordinates The intensity distribution of target information. This represents a square-integrable kernel. , The electric field distribution of the light source, c It is a set constant. It is represented as a uniform random process.

[0041] In one embodiment, , The two-dimensional Driac sampling function is determined by the characteristics of the optical orbital angular momentum encrypted hologram. If other physical degrees of freedom encryption codes are used, the function must be determined based on their physical characteristics. The form is not required, but it is not necessary to use the above form.

[0042] In one embodiment, , Indicates [0,2] π The phases are randomly distributed within the range and satisfy the following relationship: “<>” indicates the ensemble average. δ For Kronecker notation, when hour, ;when hour, .

[0043] S12: Introduce one or more additional physical degrees of freedom that are orthogonal to each other to encrypt and encode the above target information storage channel to obtain multiple corresponding encrypted holograms; The mathematical expression for the step of introducing one or more additional orthogonal physical degrees of freedom to encrypt the aforementioned target information storage channel to obtain multiple corresponding encrypted holograms is as follows: (3) in, Indicates the encrypted first... l The encrypted hologram of each storage channel, whose encrypted information is provided by N Determined by a number of distinct and mutually orthogonal physical degrees of freedom; Indicates the first l The encrypted information corresponding to the storage channel is composed of the first... i Encrypted information provided by each physical degree of freedom i ={1,2,..., N}

[0044] In one embodiment, different optical orbital angular momentum are used for encryption, and the corresponding mathematical expression is:

[0045] in Indicates the first Each storage channel uses topology load as The encrypted hologram obtained by the orbital angular momentum encryption encoding.

[0046] S13: Perform optical multiplexing operation on multiple encrypted holograms; The mathematical expression for the steps of optically multiplexing multiple encrypted holograms is as follows: (4) in, Indicates the first one used for loading k Zhang dynamic optical multiplexed hologram.

[0047] In one embodiment, optical multiplexing of multiple encrypted holograms is performed, and the corresponding mathematical expression is:

[0048] in, Indicates the number used for loading k Zhang Dongtai You L Dynamic optical multiplexing holograms obtained by encrypted multiplexing of orbital angular momentum of different topological loads.

[0049] S14: Repeating the above steps several times yields multiple different dynamic optical multiplexing holograms with specific optical coherence statistical properties. This is because... middle It has a random and uniform distribution.

[0050] The third lens 10 is used to perform Fourier transform on the decrypted multi-channel mixed optical information emitted from the digital micromirror device 9.

[0051] The mathematical expression for performing a Fourier transform on the decrypted multi-channel hybrid optical information is as follows: (5) in Indicates the first k After decrypting the dynamic optical multiplexed hologram, the light field information of the far-field observation plane is obtained. FT This is a two-dimensional discrete Fourier transform operation. Indicates the use of decryption of the first j Decryption information for target information in each storage channel Indicates the first one used for loading k Zhang dynamic optical multiplexed hologram Indicates the first j The decryption information corresponding to the storage channel contains the first... i The decryption information provided by each physical degree of freedom i ={1,2,..., N}; Indicates the first l The encrypted information corresponding to the storage channel is composed of the first... i Encrypted information provided by each physical degree of freedom i ={1,2,..., N}; Indicates the first k The first dynamic optical multiplexing hologram The storage channel is generated after the target information is optically coherently encoded; Indicates from the first k The decrypted first hologram of dynamic optical multiplexing j The light field information of the target information in each storage channel, " is the symbol for convolution operation.

[0052] In one embodiment, a Fourier transform operation is performed on the decrypted optical information, the mathematical expression of which is: .

[0053] The charge-coupled device 11 is controlled by the computer 12 to record the multi-channel mixed optical intensity information after Fourier transform. Since each storage channel is obtained by optically coherently encoding the target information, this results in good orthogonality between each storage channel (due to...). Therefore, the total far-field light intensity has a linear relationship with the intensity of each storage channel, and its mathematical expression is: (6) in Indicates the total light intensity in the far field; Indicates from the first k The decrypted first hologram of dynamic optical multiplexing j Intensity information of the target information in each storage channel; Indicates the first k After decrypting the dynamic optical multiplexed hologram, the light field information of the far-field observation plane is obtained. Indicates from the first k The decrypted first hologram of dynamic optical multiplexing j The optical field information of the target information of each storage channel FT This is a two-dimensional discrete Fourier transform operation. Indicates the first j The decryption information corresponding to the storage channel contains the first... i The decryption information provided by each physical degree of freedom i ={1,2,..., N}; Indicates the first l The encrypted information corresponding to the storage channel is composed of the first... i Encrypted information provided by each physical degree of freedom i ={1,2,..., N}; Indicates the first k The first dynamic optical multiplexing hologram The storage channel is generated after the target information is optically coherently encoded.

[0054] In one embodiment, the relationship between the total far-field light intensity and the intensity between each storage channel is as follows: .

[0055] Overlay K After the dynamic optical multiplexing hologram is generated, the charge-coupled device 11 records the multi-channel mixed optical intensity information after ensemble averaging, and its mathematical expression is: (7) in This represents multi-channel mixed optical intensity information. Indicates the decrypted first... j The light intensity information after ensemble averaging of each storage channel, i.e., the information to be read, is represented by "<>". The "<>" indicates ensemble averaging, and the ensemble averaging term on the right... I BN Background light intensity, i.e., background noise, is generated due to the mismatch between the decrypted information and the remaining physical degrees of freedom of the encrypted storage channel. I BN The intensity is negligible and does not affect the light intensity information. Reading.

[0056] In one embodiment, the charge-coupled element records the ensemble-averaged multi-channel hybrid optical intensity information, the mathematical expression of which is: .

[0057] To verify the results of this embodiment, an experiment was conducted, as shown in the attached figure. Figure 2 As shown, the number of storage channels is set to... The target information consists of four English letters: “A”, “B”, “C”, and “D”, and their intensity information is distributed within [0,1].

[0058] Specific decryption information loaded by the spatial light modulator 4 Pick The computational hologram is attached. Figure 3 As shown, its phase information is distributed in [0, 2]. π ]Inside.

[0059] Dynamic optical multiplexing holograms looping on the digital micromirror device 9, such as Figure 4 As shown, the number of superimposed dynamic optical multiplexing holograms is [number missing]. .

[0060] The results obtained after decryption from the four different storage channels are attached. Figure 5 As shown, according to the appendix Figure 5 The results show that even without subsequent processing steps, Figure 5 The target information contained in the four storage channels is still clearly displayed, namely the four English letters "A", "B", "C", and "D". (Attached) Figure 5The fact that the background noise remains low even when using the same sampling density across different channels demonstrates that the image quality degradation and capacity reduction caused by crosstalk in conventional orbital angular momentum multiplexing holography (conventional orbital angular momentum multiplexing holography is only used to illustrate this embodiment and is not generalized; the method and apparatus proposed in this paper have similar effects on optical multiplexing holography using other degrees of freedom encryption) have been greatly improved.

[0061] The system proposed in this disclosure can be implemented in other ways. For example, the system embodiments described above are merely illustrative, and the division of the modules described above is only a logical functional division. In actual implementation, there may be other division methods. For example, multiple modules may be combined or integrated into another system, or some features may be ignored or not executed.

[0062] Example 2 This embodiment provides an optical multiplexing holographic display method based on optical coherent coding, including: employing an optical multiplexing holographic display device based on optical coherent coding. The laser beam generated in the laser is magnified by the first beam expander and then enters the spatial light modulator through the first beam splitter. The spatial light modulator is loaded with a computer-generated computational hologram containing specific decryption information. The beam then reflects from the spatial light modulator into 4 f In the filtering module, the filtered outgoing light passes through the second beam splitter and is incident on the digital micromirror device, on which a dynamic optical multiplexing hologram generated by a computer is played in a loop. Then, the beam is reflected and passes through the third lens to complete the Fourier transform operation; the charge-coupled device records the multi-channel mixed optical intensity information after the Fourier transform. The descriptions of each embodiment in the above embodiments have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An optical multiplexing holographic display device based on optical coherent coding, characterized in that, include: The laser, first beam expander, first beam splitter, spatial light modulator, and 4 are connected in sequence. f The system includes a filter module, a second beam splitter, a digital micromirror device, a third lens, a charge-coupled device, and a computer. The computer is connected to the spatial light modulator, the digital micromirror device, and the charge-coupled device, respectively, and controls the loading of the computational hologram on the spatial light modulator and the loading of the dynamic optical multiplexing hologram on the digital micromirror device, as well as controlling the charge-coupled device to capture light intensity information. A digital micromirror device loads and loops a computer-generated dynamic optical multiplexing hologram. The steps for generating the computer-generated dynamic optical multiplexing hologram include: optically coherently encoding multiple target information to generate multiple corresponding target information storage channels; introducing one or more additional orthogonal physical degrees of freedom to encrypt the target information storage channels to obtain multiple corresponding encrypted coded holograms; optically multiplexing the multiple encrypted coded holograms; repeating the above steps several times to obtain multiple different dynamic optical multiplexing holograms with specific optical coherence statistical properties. The mathematical expression of the steps of optically coherently encoding multiple target information to generate multiple corresponding target information storage channels is as follows: ; in Indicates the first k The first dynamic optical multiplexing hologram The storage channel generated after optical coherence encoding of target information r Spatial location coordinates, The non-negative pattern weights. ; Represents the position in frequency space coordinates Intensity distribution of target information; This represents a square-integrable kernel. , The electric field distribution of the light source, c Let it be a set constant; It is represented as a uniform random process.

2. The optical multiplexing holographic display device based on optical coherence coding according to claim 1, characterized in that, A spatial light modulator loads a computer-generated computational hologram; the mathematical form of the computational hologram is expressed as: in, Indicates the use of decryption of the first j The decryption information of the target information of each storage channel is provided by N Determined by a number of distinct and mutually orthogonal physical degrees of freedom; Indicates the first j The decryption information corresponding to the storage channel is from the first... i The decryption information provided by each physical degree of freedom i ={1,2,..., N } 3. The optical multiplexing holographic display device based on optical coherence coding according to claim 1, characterized in that, The mathematical expression for the step of introducing one or more additional orthogonal physical degrees of freedom to encrypt the aforementioned target information storage channel to obtain multiple corresponding encrypted holograms is as follows: in, Indicates the encrypted first... l The encrypted hologram of each storage channel, whose encrypted information is provided by N Determined by a number of distinct and mutually orthogonal physical degrees of freedom; Indicates the first l The encrypted information corresponding to the storage channel is composed of the first... i Encrypted information provided by each physical degree of freedom i ={1,2,..., N } 4. The optical multiplexing holographic display device based on optical coherence coding according to claim 1, characterized in that, The mathematical expression for the steps of optically multiplexing multiple encrypted holograms is as follows: in, Indicates the first one used for loading k Zhang dynamic optical multiplexed hologram.

5. The optical multiplexing holographic display device based on optical coherence coding according to claim 1, characterized in that, The third lens is used to perform Fourier transform operations on the decrypted multi-channel mixed optical information emitted from the digital micromirror device. The Fourier transform operation performed on the decrypted multi-channel hybrid optical information is expressed as follows: in Indicates the first k After decrypting the dynamic optical multiplexed hologram, the light field information of the far-field observation plane is obtained. FT This is a two-dimensional discrete Fourier transform operation. Indicates the use of decryption of the first j Decryption information for target information in each storage channel Indicates the first one used for loading k Zhang dynamic optical multiplexing hologram Indicates the first j The decryption information corresponding to the storage channel is from the first... i The decryption information provided by each physical degree of freedom i ={1,2,..., N }; Indicates the first l The encrypted information corresponding to the storage channel is composed of the first... i Encrypted information provided by each physical degree of freedom i ={1,2,..., N }; Indicates the first k The first dynamic optical multiplexing hologram The storage channel is generated after the target information is optically coherently encoded; Indicates from the first k The decrypted first hologram of dynamic optical multiplexing j The optical field information of the target information in each storage channel, " is the symbol for convolution operation.

6. The optical multiplexing holographic display device based on optical coherence coding according to claim 1, characterized in that, The charge-coupled device (CCD) records multi-channel mixed optical intensity information after Fourier transform; each storage channel exhibits good orthogonality, therefore, the total far-field light intensity has a linear relationship with the intensity of each storage channel, and its mathematical expression is: in Indicates the total light intensity in the far field; Indicates from the first k The decrypted first hologram of dynamic optical multiplexing j Intensity information of the target information in each storage channel; Indicates the first k After decrypting the dynamic optical multiplexed hologram, the light field information of the far-field observation plane is obtained. Indicates from the first k The decrypted first hologram of dynamic optical multiplexing j The optical field information of the target information of each storage channel FT This is a two-dimensional discrete Fourier transform operation. Indicates the first j The decryption information corresponding to the storage channel is from the first... i The decryption information provided by each physical degree of freedom i ={1,2,..., N }; Indicates the first l The encrypted information corresponding to the storage channel is composed of the first... i Encrypted information provided by each physical degree of freedom i ={1,2,..., N }; Indicates the first k The first dynamic optical multiplexing hologram The storage channel is generated after the target information is optically coherently encoded.

7. The optical multiplexing holographic display device based on optical coherence coding according to claim 6, characterized in that, Overlay K After the dynamic optical multiplexing hologram is generated, the charge-coupled device records the multi-channel mixed optical intensity information after ensemble averaging. Its mathematical expression is: in This represents multi-channel mixed optical intensity information. Indicates the decrypted first... j The light intensity information after ensemble averaging of each storage channel, i.e., the information to be read, is represented by "<>". The "<>" indicates ensemble averaging, and the ensemble averaging term on the right... I BN Background light intensity, i.e., background noise, is generated due to the mismatch between the decrypted information and the remaining physical degrees of freedom of the encrypted storage channel. I BN The intensity is negligible and does not affect the light intensity information. Reading.

8. A method for optical multiplexing holographic display based on optical coherence coding, characterized in that, include: An optical multiplexing holographic display device based on optical coherence coding, as described in any one of claims 1-7, is used. The laser beam generated in the laser is magnified by the first beam expander and then enters the spatial light modulator through the first beam splitter. The spatial light modulator is loaded with a computer-generated computational hologram containing specific decryption information. The beam then reflects from the spatial light modulator into 4 f In the filtering module, the filtered outgoing light passes through the second beam splitter and is incident on the digital micromirror device, on which a dynamic optical multiplexing hologram generated by a computer is played in a loop. Then, the beam is reflected and passes through the third lens to complete the Fourier transform operation; the charge-coupled element records the multi-channel mixed optical intensity information after the Fourier transform.

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