SLM-based high-diffraction-order color holographic representation method and system

Abstract

The invention discloses a high-diffraction-order color holographic representation method and system based on SLM, and relates to the technical field of dynamic holographic display, and the method comprises the steps: a processor processes object information and laser light source information to obtain hologram generation data, and loads the hologram generation data to a data input port of a spatial light modulator; generating a light wave field carrying object information; a data output port of the spatial light modulator is based on a light wave field carrying object information, a laser emits a laser light source with a corresponding color by using a time division multiplexing technology, the laser light source is adjusted by an adjusting device and reflected by a beam splitter prism and then irradiates a liquid crystal screen of the spatial light modulator, and an initial image is generated and then reflected to the beam splitter prism. A color holographic image is transmitted; wherein the adjusting device is used for adjusting the actual incidence angle and height of the laser light sources with the corresponding colors emitted by the laser, so that the first diffraction orders of all the emitted laser light sources are aligned in space. Therefore, a high-quality color holographic image is provided.

Description

Technical Field

[0001] The present application relates to the technical field of dynamic holographic display, and particularly to a high diffraction order color holographic reconstruction method and system based on an SLM. Background Art

[0002] With the rapid development of virtual reality, augmented reality, and three-dimensional display technologies, dynamic holographic display technology, as the core direction of the next-generation display technology, has received extensive attention. Holographic display technology can provide a more realistic and immersive visual experience, and thus has broad application prospects in fields such as entertainment, education, medical treatment, and industrial design. Computer-Generated Holograms (CGH) technology, especially CGH technology based on a Spatial Light Modulator (SLM), has become the mainstream solution for realizing dynamic holographic display due to its programmability and real-time regulation ability. However, although significant progress has been made in monochromatic holographic display using CGH technology, it still faces severe challenges in the field of multi-wavelength color holographic reconstruction, seriously restricting the practical application process of holographic display technology.

[0003] Currently, color holographic reconstruction methods based on an SLM mainly adopt time-division multiplexing or spatial multiplexing technology. Time-division multiplexing technology realizes color synthesis by quickly switching the red, green, and blue light sources. However, this technology is limited by the refresh rate of the SLM and the response speed of the light source, and is prone to color flicker phenomena, affecting the viewing experience. Spatial multiplexing technology uses a microlens array or pixel-level beam splitting elements for spatial superposition of the three-color light. However, this technology will significantly reduce the spatial resolution, resulting in a decline in image quality. It can be seen that the existing color holographic reconstruction methods cannot reconstruct high-quality color holographic images. Summary of the Invention

[0004] The purpose of the present application is to provide a high diffraction order color holographic reconstruction method and system based on an SLM, which can provide higher-quality color holographic images.

[0005] To achieve the above purpose, the present application provides the following solutions:

[0006] In a first aspect, the present application provides a high diffraction order color holographic reconstruction method based on an SLM, including:

[0007] A processor uses a hologram generation algorithm to process the acquired object information and laser light source information to obtain hologram generation data; the object information is a three-dimensional model of an object, the laser light source information is the wavelengths of the three-color laser light sources emitted by a laser, and the hologram generation data is a complex value matrix containing the phase information and amplitude information of the object.

[0008] The processor loads the hologram generation data into the data input port of the spatial light modulator, enabling the liquid crystal screen of the spatial light modulator to generate a light wave field carrying object information;

[0009] Based on the light wave field carrying object information, the data output port of the spatial light modulator uses time-division multiplexing technology to make the laser emit laser light sources of corresponding colors, and after the laser light sources of corresponding colors are adjusted by the adjustment device and reflected by the beam splitter prism, they are irradiated onto the liquid crystal screen of the spatial light modulator to generate an initial image, which is then reflected onto the beam splitter prism, and the beam splitter prism transmits a high-fidelity color holographic image;

[0010] Among them, the adjustment process of the adjustment device is as follows: the adjustment device adjusts the actual incident angle and actual height of the laser light source of the corresponding color emitted by the laser, so that the first diffraction orders of all the laser light sources emitted by the laser are spatially aligned.

[0011] In a second aspect, the present application provides a high-diffraction-order color holographic reproduction system based on an SLM, including: the high-diffraction-order color holographic reproduction system based on an SLM includes a processor, a spatial light modulator, a laser, an adjustment device, and a beam splitter prism;

[0012] The processor is used for:

[0013] Using a hologram generation algorithm to process the acquired object information and laser light source information to obtain hologram generation data; the object information is the three-dimensional model of the object, the laser light source information is the wavelengths of the three-color laser light sources emitted by the laser, and the hologram generation data is a complex value matrix containing object phase information and amplitude information;

[0014] Loading the hologram generation data into the data input port of the spatial light modulator;

[0015] The spatial light modulator is used for:

[0016] Generating a light wave field carrying object information according to the hologram generation data;

[0017] According to the light wave field carrying object information, using time-division multiplexing technology to make the laser emit laser light sources of corresponding colors, and transmitting the laser light sources of corresponding colors to the adjustment device;

[0018] The adjustment device is used to adjust the actual incident angle and actual height of the laser light source of the corresponding color emitted by the laser, so that the first diffraction orders of all the laser light sources emitted by the laser are spatially aligned;

[0019] The beam splitter prism is used to reflect the laser light source of the corresponding color adjusted by the adjustment device onto the liquid crystal screen of the spatial light modulator;

[0020] The spatial light modulator is further configured to reflect the generated initial image onto a beam splitter prism, so that the beam splitter prism transmits a high-fidelity color holographic image.

[0021] According to the specific embodiments provided in the present application, the following technical effects are disclosed in the present application:

[0022] The present application provides a high diffraction order color holographic reproduction method and system based on an SLM. In the present application, the actual incident angle and actual height of the three-color laser light source emitted by the laser are precisely controlled by an adjustment device, so that the first diffraction orders of the red, green, and blue laser light sources are spatially aligned. The first diffraction order light carries complete phase and amplitude information, can accurately reproduce the three-dimensional structure and surface characteristics of an object, and the first diffraction order light avoids the interference of direct current components and speckle noise, thereby improving the image contrast and clarity. At the same time, by combining the time-division multiplexing technology, the red, green, and blue laser light sources are quickly switched, so that high-resolution, wide color gamut, and low-noise color holographic display can be achieved. Description of the Drawings

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 It is a schematic flowchart of a high diffraction order color holographic reproduction method based on an SLM provided by an embodiment of the present application;

[0025] Figure 2 It is a schematic diagram of a hologram diffraction pattern provided by an embodiment of the present application;

[0026] Figure 3 It is a schematic diagram of the precise alignment of the negative first diffraction orders of the three-color laser light sources provided by an embodiment of the present application;

[0027] Figure 4 It is a schematic diagram of a color hologram reproduction laser light path provided by an embodiment of the present application;

[0028] Figure 5 It is a schematic structural diagram of a high diffraction order color holographic reproduction system based on an SLM provided by another embodiment of the present application.

[0029] Reference numerals: 301: processor; 302: spatial light modulator; 303: laser; 304: adjustment device; 305: beam splitter prism; 306: polarizer; 307: collimating lens; 308: mirror; 309: dichroic mirror. Detailed implementation manners

[0030] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0031] Due to the differences in the diffraction characteristics of light with different wavelengths on the SLM, it is difficult to achieve precise matching of the three-color diffraction light fields by traditional methods. Moreover, in the prior art, the zero-order diffraction light is mostly used for hologram reconstruction. However, the phase information carried by the zero-order diffraction light is incomplete and contains a strong DC component, resulting in a decrease in the contrast of the reconstructed hologram, a limited color gamut, and obvious speckle noise, seriously affecting the quality and visual effect of the hologram. In view of this, by deeply analyzing the grating-like characteristics of the SLM pixel array, a modified grating equation is established, and pixel-level spatial matching of the first diffraction order of the three-color laser light sources is achieved.

[0032] To make the above objects, features, and advantages of the present application more obvious and understandable, the present application will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0033] In an exemplary embodiment, as Figure 1 shown, a high-diffraction-order color holographic reproduction method based on an SLM is provided, including the following steps 201 to 203. Among them:

[0034] Step 201, the processor uses a hologram generation algorithm to process the obtained object information and laser light source information to obtain hologram generation data; the object information is the three-dimensional model of the object, the laser light source information is the wavelengths of the three-color laser light sources emitted by the laser, and the hologram generation data is a complex value matrix containing the phase information and amplitude information of the object.

[0035] Step 202, the processor loads the hologram generation data into the data input port of the spatial light modulator, so that the liquid crystal screen of the spatial light modulator generates a light wave field carrying the object information.

[0036] Step 203, based on the light wave field carrying the object information at the data output port of the spatial light modulator, the laser emits the corresponding color laser light source by using the time-division multiplexing technology, and after the corresponding color laser light source is adjusted by the adjustment device and reflected by the beam splitter prism, it is irradiated onto the liquid crystal screen of the spatial light modulator, and after generating an initial image, it is reflected onto the beam splitter prism, so that the beam splitter prism transmits a high-fidelity color holographic image.

[0037] Among them, the adjustment process of the adjustment device is as follows: the adjustment device adjusts the actual incident angle and actual height of the laser light source of the corresponding color emitted by the laser, so that the first diffraction orders of all the laser light sources emitted by the laser are spatially aligned.

[0038] Implement the above steps 201 to 203. By precisely controlling the actual incident angle and height of the three-color laser light sources emitted by the laser through the adjustment device, the first diffraction orders of the red, green, and blue laser light sources are spatially aligned. The first diffraction order light carries complete phase and amplitude information, can accurately reproduce the three-dimensional structure and surface characteristics of the object, and the first diffraction order light avoids the interference of DC components and speckle noise, thereby improving the image contrast and clarity. At the same time, by combining the time-division multiplexing technology and quickly switching the red, green, and blue laser light sources, high-resolution, wide-color gamut, and low-noise color holographic display can be achieved.

[0039] Further, before the time-division multiplexing technology is used to make the laser emit the laser light source of the corresponding color based on the optical wave field carrying the object information at the data output port of the spatial light modulator in step 203, and the laser light source of the corresponding color is irradiated onto the liquid crystal screen of the spatial light modulator after being adjusted by the adjustment device and reflected by the beam splitter prism, generating an initial image and then reflected onto the beam splitter prism, and the beam splitter prism transmits a high-fidelity color holographic image, the following steps are also included:

[0040] The processor calculates the theoretical incident angle and theoretical height of the three-color laser light sources based on the preset common diffraction angle and the corrected grating equation, and inputs the theoretical height of the theoretical incident angle of the three-color laser light sources into the adjustment device through the control component; the corrected grating equation is determined based on the periodic characteristics of the grating-like of the spatial light modulator; the control component includes a spatial modulator, a laser, and a control line.

[0041] During the reconstruction process of the hologram, the core technology is to precisely control light waves using a spatial light modulator. CGH generation involves the processor converting the three-dimensional model of an object into hologram generation data (i.e., a complex value matrix containing the phase information and amplitude information of the object) using hologram generation algorithms. Commonly used hologram generation algorithms include the point source method, the angular spectrum method, and the Fresnel diffraction method. Subsequently, the processor of the computer efficiently and accurately loads the generated hologram generation data onto a high-resolution SLM through a dedicated data transmission interface. The SLM, as a key optical component, consists of a regularly arranged pixel array, and each pixel has the ability to independently modulate the phase or amplitude of light waves. When the laser light source emitted by the laser passes through the precise beam expansion and collimation of the polarizer and collimating lens and irradiates the surface of the SLM loaded with hologram generation data, the SLM will finely modulate the phase and amplitude of the incident laser light source according to the loaded data. Through this modulation, the information carried by the light source is re-encoded, laying the foundation for the subsequent high-quality reconstruction of the object image through the optical system. Throughout the process, the SLM plays a bridging role, converting the digital information generated by the computer into optical signals that can be processed in the optical field, which is the core link for realizing CGH reconstruction.

[0042] More specifically, the SLM consists of a regularly arranged pixel array. These pixels can independently modulate the phase or amplitude of light waves and have periodic characteristics similar to a grating. Essentially, the SLM is a two-dimensional grating composed of a pixel array. When the incident light wave passes through this periodic structure, complex diffraction phenomena will occur, forming multiple diffraction spots (such as ±1st order, ±2nd order, etc.), as Figure 2 shown. The grating diffraction formula is:

[0043] d·(sinθ m - sinθ i ) = mλ;

[0044] where, d is the grating period (i.e., pixel pitch); θ m is the diffraction angle of the mth order; θ i is the incident angle of the laser light source; m is the diffraction order; λ is the wavelength of the incident laser light source.

[0045] However, a single pixel is usually not sufficient to fully represent the required phase or amplitude information. Therefore, multiple pixels are often combined together to form a larger and functionally complete modulation unit. This combination may be a 2×2, 3×3 or larger pixel array. When multiple pixels are combined into a modulation unit, the effective period of the grating changes. If K 2 pixels form a unit, then the new effective period is no longer the pitch d of a single pixel, but becomes Kd. Based on this new periodic structure, the traditional grating diffraction equation needs to be adjusted accordingly. The modified grating equation becomes:

[0046] Kd·(sinθ m -sinθ i )=mλ;

[0047] Wherein, Kd is the grating period of multiple pixels, K is the number of pixels, d is the pixel pitch; θ m is the diffraction angle of the m-th order, that is, the common diffraction angle; θ i is the incident angle of the incident laser light source; m is the diffraction order; λ is the wavelength of the incident laser light source.

[0048] Furthermore, to achieve high-quality color hologram reproduction, it is necessary to precisely align the first diffraction orders of the three-color lasers (such as using the -1st order in the y-axis direction, let m = -1), as Figure 3 shown. Therefore, based on the preset common diffraction angle and the corrected grating equation, the processor calculates the theoretical incident angle and theoretical height of the three-color laser light sources, and inputs the theoretical height of the theoretical incident angle of the three-color laser light sources into the adjustment device through the control component, so that the adjustment device adjusts the actual incident angle and actual height of the laser light sources of the corresponding colors emitted by the laser, and aligns the first diffraction orders of all the laser light sources emitted by the laser in space. Specifically, it includes:

[0049] The first step: Select a suitable common diffraction angle θ m . Usually, let θ m = 0. This setting can make the first diffraction orders of the three-color laser light sources propagate horizontally, facilitating subsequent unified analysis and adjustment of the optical path, simplifying the optical path design and calculation process, and providing convenient conditions for achieving precise alignment of the three-color laser light sources.

[0050] The second step: Based on the preset common diffraction angle and the corrected grating equation, calculate the theoretical incident angles of the three-color laser light sources respectively. Specifically, according to the corrected grating equation, calculate the sine values of the theoretical incident angles of the red laser light source (r), green laser light source (g), and blue (b) three-color laser light sources respectively:

[0051]

[0052] Wherein, Kd is the grating period of multiple pixels, K is the number of pixels, d is the pixel pitch; θ m is the diffraction angle of the m-th order, that is, the common diffraction angle; θ i,c is the incident angle of the three-color laser light sources; λ c is the wavelength of the three-color laser light sources; r is the red laser light source, g is the green laser light source, and b is the blue laser light source.

[0053] Then use the arcsine function to calculate the theoretical incident angles of the three-color laser light sources respectively:

[0054] θ i,c = arcsin(sinθ i,c ), c ∈ {r, g, b}。

[0055] Thus, the accurate incident angle of each color laser light source at a specific common diffraction angle can be determined, laying the foundation for subsequent calculations.

[0056] Step 3: Theoretical heights of the three-color laser light sources. Based on the theoretical incident angles of the three-color laser light sources, the central position height of the spatial light modulator, and the distance from the spatial light modulator to the three-color laser light sources, calculate the theoretical heights of the three-color laser light sources respectively, specifically:

[0057] h = H SLM - L·tan(θ i,c );

[0058] where h is the theoretical height of the three-color laser light source; H SLM is the central position height of the spatial light modulator; L is the distance from the spatial light modulator to the three-color laser light source; θ i,c is the theoretical incident angle of the three-color laser light source.

[0059] The height positions of each color laser light source in the optical system can be obtained, thus providing data support for subsequent precise optical path adjustment.

[0060] Step 4: Adjust the optical path. According to the theoretical incident angles and theoretical heights of the three-color laser light sources, adjust the actual incident angles and actual heights of the three-color laser light sources so that the first diffraction orders of the three-color laser light sources are spatially aligned, ensuring that different color laser light sources accurately overlap during propagation, providing guarantee for high-quality color holographic image reconstruction.

[0061] Through this precise optical path design and adjustment, it can be ensured that the three-color holograms are precisely aligned in space, thus realizing high-quality color holographic image reconstruction. This method not only improves the spatial resolution and color restoration degree of the image, but also lays the foundation for the development of dynamic holographic display technology.

[0062] It can be seen that, as Figure 4 shown, the reproduction of color holograms requires laser light sources of different colors and wavelengths. Usually, laser light sources with three wavelengths of red (638 nm), green (520 nm), and blue (450 nm) are used, as well as the corresponding three-color hologram generation data. The SLM sequentially loads the three-color hologram generation data, and then irradiates with the corresponding color and wavelength laser light sources to generate red, green, and blue three-color holograms. Finally, through precise spatial and temporal multiplexing technology, these three-color holograms are synthesized to finally obtain a high-fidelity color holographic image.

[0063] Based on the same inventive concept, an embodiment of the present application further provides a high diffraction order color holographic reproduction system for implementing the above-mentioned SLM-based high diffraction order color holographic reproduction method. The solution provided by this system for solving problems is similar to the solution described in the above method. Therefore, the specific limitations in one or more embodiments of the high diffraction order color holographic reproduction system provided below can refer to the limitations on the high diffraction order color holographic reproduction method in the above text, and will not be repeated here.

[0064] In an exemplary embodiment, as Figure 5 shown, a high diffraction order color holographic reproduction system is provided, including: a processor 301, a spatial light modulator 302, a laser 303, an adjustment device 304, and a beam splitter prism 305; the processor 301 is configured to:

[0065] Use a hologram generation algorithm to process the acquired object information and laser light source information to obtain hologram generation data; the object information is the three-dimensional model of the object, the laser light source information is the wavelength of the three-color laser light source emitted by the laser, and the hologram generation data is a complex value matrix containing the object phase information and amplitude information.

[0066] Load the hologram generation data into the data input port of the spatial light modulator.

[0067] The spatial light modulator 302 is configured to:

[0068] Generate a light wave field carrying object information according to the hologram generation data.

[0069] According to the light wave field carrying object information, use time-division multiplexing technology to make the laser 303 emit laser light sources of corresponding colors, and emit the laser light sources of corresponding colors to the adjustment device.

[0070] The adjustment device 304 is configured to adjust the actual incident angle and actual height of the laser light sources of corresponding colors emitted by the laser, so that the first diffraction orders of all the laser light sources emitted by the laser are spatially aligned.

[0071] The beam splitter prism 305 is configured to reflect the laser light sources of corresponding colors adjusted by the adjustment device to the liquid crystal screen of the spatial light modulator.

[0072] The spatial light modulator 302 is further configured to reflect the generated initial image to the beam splitter prism, so that the beam splitter prism transmits a high-fidelity color holographic image.

[0073] The processor 301 is further configured to calculate the theoretical incident angle and the theoretical height of the three-color laser light source based on a preset common diffraction angle and a corrected grating equation, and input the theoretical incident angle and the theoretical height of the three-color laser light source into the adjustment device through a control component.

[0074] The adjustment device 304 includes an incident angle adjustment module and a height adjustment module; the incident angle adjustment module includes a polarizer 306, a collimating lens 307, a reflector 308, and a dichroic mirror 309.

[0075] The incident angle adjustment module is configured to adjust the actual incident angle of the laser light source of the corresponding color emitted by the laser according to the laser light source of the corresponding color emitted by the laser and the theoretical incident angle of the three-color laser light source received. Specifically: the polarizer 306 is configured to adjust the polarization direction of the laser light source to ensure that all laser light sources have the same polarization state, which is beneficial to subsequent laser light source synthesis and the modulation efficiency of the SLM; the collimating lens 307 is configured to convert the divergent laser light source into a parallel laser light source, improve the reconstruction quality of the hologram, and reduce aberration; the reflector 308 is configured to adjust the actual incident angle of the red laser light source to ensure that the red laser light source can be correctly incident on the SLM; the dichroic mirror 309 is configured to adjust the actual incident angle of the laser light source of the corresponding color (i.e., the green laser light source or the blue laser light source) to ensure that the laser light source of the corresponding color can be correctly incident on the SLM.

[0076] The height adjustment module is configured to adjust the actual height of the laser light source of the corresponding color according to the laser light source of the corresponding color emitted by the laser and the theoretical height of the three-color laser light source received.

[0077] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0078] Specific examples are used in this article to elaborate on the principles and implementation manners of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A high diffraction order color holographic reproduction method based on SLM, characterized in that: The SLM-based high diffraction order color holographic reproduction method comprises: The processor processes the acquired object information and laser light source information using a hologram generation algorithm to obtain hologram generation data; the object information is a three-dimensional model of the object, the laser light source information is the wavelength of the three-color laser light source emitted by the laser, and the hologram generation data is a complex value matrix containing the object phase information and amplitude information; The processor loads the hologram generation data into the data input port of the spatial light modulator, so that the liquid crystal screen of the spatial light modulator generates a light wave field carrying the object information; The data output port of the spatial light modulator is based on the optical wave field carrying the object information, and uses the time-division multiplexing technology to make the laser emit a laser light source of the corresponding color, and the laser light source of the corresponding color is adjusted by the adjustment device and reflected by the beam splitter prism to irradiate the liquid crystal screen of the spatial light modulator, and the initial image is reflected on the beam splitter prism after being generated, so that the beam splitter prism transmits a high-fidelity color holographic image; The adjustment process of the adjustment device is as follows: the adjustment device adjusts the actual incident angle and actual height of the laser light source of the corresponding color emitted by the laser, so that the first diffraction orders of all laser light sources emitted by the laser are spatially aligned.

2. The high diffraction order color holographic reproduction method based on SLM according to claim 1, characterized in that: Based on the light wave field carrying the object information, the data output port of the spatial light modulator uses the time-division multiplexing technology to make the laser emit a laser light source of the corresponding color, and the laser light source of the corresponding color is adjusted by the adjustment device and reflected by the beam splitter prism to irradiate the liquid crystal screen of the spatial light modulator, and the initial image is reflected on the beam splitter prism after being generated, so that the beam splitter prism transmits a high-fidelity color holographic image, and also includes: The processor calculates the theoretical incident angle and theoretical height of the three-color laser light source based on the preset common diffraction angle and the corrected grating equation, and inputs the theoretical incident angle and theoretical height of the three-color laser light source into the adjustment device through the control component; the corrected grating equation is determined based on the grating-like periodic characteristics of the spatial light modulator.

3. The high diffraction order color holographic reproduction method based on SLM according to claim 1, characterized in that: The adjusting device adjusts the actual incident angle and actual height of the laser light source of the corresponding color emitted by the laser so that the first diffraction orders of all the laser light sources emitted by the laser are aligned in space, specifically including: The adjusting device determines the theoretical incident angle and theoretical height of the laser light source of the corresponding color according to the laser light source of the corresponding color emitted by the laser and the theoretical incident angle and theoretical height of the three-color laser light source received; The adjusting device adjusts the actual incident angle and actual height of the laser light source of the corresponding color according to the theoretical incident angle and theoretical height of the laser light source of the corresponding color, so that the first diffraction orders of all laser light sources emitted by the laser are aligned in space.

4. The high diffraction order color holographic reproduction method based on SLM according to claim 2, characterized in that: The processor calculates the theoretical incident angle and theoretical height of the three-color laser light source based on the preset common diffraction angle and the corrected grating equation, including: Based on the preset common diffraction angle and the corrected grating equation, the theoretical incident angles of the three-color laser light sources are calculated respectively; Based on the theoretical incident angle of the three-color laser light source, the center position height of the spatial light modulator and the distance from the spatial light modulator to the laser, the theoretical heights of the three-color laser light sources are calculated respectively.

5. The high diffraction order color holographic reproduction method based on SLM according to claim 2, characterized in that: The modified grating equation is: Where Kd is the grating period of multiple pixels, K is the number of pixels, and d is the pixel spacing; θ m is the mth order diffraction angle, that is, the common diffraction angle; θ i,c is the incident angle of the three-color laser light source; c are the wavelengths of the three-color laser light sources; r is the red laser light source, g is the green laser light source, and b is the blue laser light source.

6. The high diffraction order color holographic reproduction method based on SLM according to claim 4, characterized in that: Based on the theoretical incident angle of the three-color laser light source, the center position height of the spatial light modulator and the distance from the spatial light modulator to the laser, the theoretical heights of the three-color laser light source are calculated respectively, specifically: h=H SLM -L·time(θ i,c ); Where, h is the theoretical height of the three-color laser light source; H SLM is the height of the center position of the spatial light modulator; L is the distance from the spatial light modulator to the laser; θ i,c is the theoretical incident angle of the three-color laser light source.

7. The high diffraction order color holographic reproduction method based on SLM according to claim 1, characterized in that: The three-color laser light source includes a red laser light source, a green laser light source and a blue laser light source; wherein the wavelength of the red laser light source is 638nm, the wavelength of the green laser light source is 520nm, and the wavelength of the red laser light source is 450nm.

8. A high diffraction order color holographic reproduction system based on SLM, characterized in that: The SLM-based high-diffraction-order color holographic reconstruction system includes a processor, a spatial light modulator, a laser, an adjustment device, and a beam splitter prism; The processor is configured to: Using a hologram generation algorithm, the acquired object information and laser light source information are processed to obtain hologram generation data; the object information is a three-dimensional model of the object, the laser light source information is the wavelength of the three-color laser light source emitted by the laser, and the hologram generation data is a complex value matrix containing the object phase information and amplitude information; Loading hologram generation data into a data input port of a spatial light modulator; The spatial light modulator is used for: generating a light wave field carrying object information according to the hologram generation data; According to the optical wave field carrying the object information, the laser emits a laser light source of a corresponding color by using a time-division multiplexing technology, and emits the laser light source of the corresponding color to the adjustment device; The adjusting device is used to adjust the actual incident angle and actual height of the laser light source of the corresponding color emitted by the laser, so that the first diffraction orders of all the laser light sources emitted by the laser are aligned in space; The beam splitter prism is used to reflect the laser light source of the corresponding color adjusted by the adjustment device to the liquid crystal screen of the spatial light modulator; The spatial light modulator is also used to reflect the generated initial image onto the beam splitter prism, so that the beam splitter prism transmits a high-fidelity color holographic image.

9. The high diffraction order color holographic reconstruction system based on SLM according to claim 8, characterized in that: The processor is also used to calculate the theoretical incident angle and theoretical height of the three-color laser light source based on a preset common diffraction angle and a corrected grating equation, and input the theoretical incident angle and theoretical height of the three-color laser light source into the adjustment device through the control component.

10. The high diffraction order color holographic reproduction system based on SLM according to claim 9, characterized in that: The adjustment device comprises an incident angle adjustment module and a height adjustment module; the incident angle adjustment module comprises a polarizer, a collimating lens, a dichroic mirror and a reflector; The incident angle adjustment module is used to adjust the actual incident angle of the laser light source of the corresponding color according to the laser light source of the corresponding color emitted by the laser and the theoretical incident angle of the received three-color laser light source; The height adjustment module is used to adjust the actual height of the laser light source of the corresponding color according to the laser light source of the corresponding color emitted by the laser and the theoretical height of the received three-color laser light source.

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