Diffractive optical elements, methods and systems for designing diffractive optical elements, light projection devices, apparatuses, storage media

Abstract

The application discloses a diffractive optical element and a design method and system thereof, a light projection device, equipment and a storage medium. The design method comprises the following steps: obtaining a current phase distribution map to be processed in a current cycle process; perturbing the current phase distribution map to be processed to obtain a perturbed phase distribution map; performing Gaussian blurring on the perturbed phase distribution map to obtain a Gaussian-blurred phase distribution map; simulating the Gaussian-blurred phase distribution map to determine whether a simulation result meets a preset requirement; and performing the above steps at least once in a loop until the simulation result meets the preset requirement, thereby obtaining a target phase distribution map for processing the diffractive optical element. The target phase distribution map is the Gaussian-blurred phase distribution map whose simulation result meets the preset requirement, and the target phase distribution map is used for representing the distribution of microstructures on the diffractive optical element. According to the design method, the diffractive optical element is easier to process while meeting the optical performance requirement.

Description

Technical Field

[0001] This application relates to the field of diffractive optics technology, and more specifically to a diffractive optical element and its design method and system, a light projection device, an apparatus, and a storage medium. Background Technology

[0002] A diffractive optical element (DOE) is an optical element designed using the principles of diffraction optics. Typically, for incident laser light of a specific wavelength, a micro- or nano-structure is designed on the surface to modulate the energy and phase of the laser light, thereby achieving the desired output diffraction pattern.

[0003] Collimated optical dot arrays (DOEs) are a widely used type of DOE product, with important applications in fields such as structured light and dTOF. Currently, mainstream dTOF solutions require robust fabrication of the DOE. Producing a continuous 2D grating is extremely beneficial for fabrication stability. However, using large-pixel phase maps for 2D grating optimization presents two problems: first, the large edge length and area of ​​the large-pixel phase map cause significant vector effects, making it difficult to optimize a good 2D grating; second, even if optimization with these significant vector effects yields good results, fabricating such a sharp-edged structure is a major challenge, leading to significant design and fabrication errors.

[0004] Therefore, improvements are needed to at least partially address the aforementioned problems. Summary of the Invention

[0005] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. The summary section of this invention is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0006] To at least partially solve the above-mentioned problems, according to a first aspect of the present invention, a method for designing a diffractive optical element is provided, characterized by comprising:

[0007] Obtain the current phase distribution map to be processed in the current loop process, wherein when the current loop process is the first loop process, the current phase distribution map to be processed includes the initial phase distribution map of the diffractive optical element, and when the current loop process is a loop process after the first loop process, the current phase distribution map to be processed includes the perturbation phase distribution map obtained in the previous loop process before the current loop process;

[0008] The current phase distribution map to be processed is perturbed to obtain a perturbed phase distribution map;

[0009] Gaussian blurring is applied to the perturbation phase distribution map to obtain the Gaussian blurred phase distribution map;

[0010] Simulate the phase distribution map after Gaussian blurring and determine whether the simulation results meet the preset requirements;

[0011] The above steps are repeated at least once until the simulation result meets the preset requirements, thereby obtaining a target phase distribution map for processing the diffractive optical element. The target phase distribution map is a Gaussian blurring phase distribution map after the simulation result meets the preset requirements. The target phase distribution map is used to characterize the distribution of microstructures on the diffractive optical element.

[0012] For example, the current phase distribution map to be processed includes continental block regions and gap regions located between adjacent continental block regions;

[0013] The step of perturbing the current phase distribution map to obtain a perturbed phase distribution map includes:

[0014] Obtain the edge pixels located at the edge of the continental block region, and set the logical value of the edge pixels to be the same as the logical value of the pixels within the continental block region, and / or

[0015] Identify isolated islands and set their logical values ​​to be the same as the logical values ​​of the pixels in their neighborhood.

[0016] For example, obtaining edge pixels located at the edge of the continental block region and setting the logical value of the edge pixels to be the same as the logical value of pixels within the continental block region includes:

[0017] Determine whether the logical values ​​of the neighboring pixels in the eight-neighborhood of the current pixel with a logical value of 1 in the current phase distribution map are 0, wherein the logical value of each pixel in the continental block region is 1, and the logical value of each pixel in the gap region is 0.

[0018] When the logical values ​​of all neighboring pixels are 0, it is determined whether the logical values ​​of at least four pixels located outside the neighboring pixels and adjacent to the neighboring pixels are 0. When the logical value of at least one of the at least four pixels is not 0, the neighboring pixels between the current pixel and any of the at least four pixels whose logical value is not 0 are determined as the edge pixels, and the logical value of the edge pixels is set to 1.

[0019] For example, the step of acquiring isolated islands and setting the logical value of the isolated island to be the same as the logical value of the pixels in the neighboring region of the isolated island includes:

[0020] Determine whether the logical values ​​of the neighboring pixels in the eight-neighborhood of the current pixel with a logical value of 1 in the current phase distribution map are 0, wherein the logical value of each pixel in the continental block region is 1, and the logical value of each pixel in the gap region is 0.

[0021] When the logical values ​​of the neighboring pixels are all 0, determine whether the logical values ​​of at least four pixels located outside the neighboring pixels and adjacent to the neighboring pixels are 0. When the logical values ​​of the at least four pixels are all 0, determine that the current pixel is the island.

[0022] Set the logical value of the isolated island to 0.

[0023] For example, the at least four pixels include four pixels that are adjacent to the four neighboring pixels to the left, right, top and bottom of the current pixel and located on the side of the four neighboring pixels that are away from the current pixel.

[0024] For example, the Gaussian blur is performed using the following formula:

[0025]

[0026]

[0027] Where is a two-dimensional Gaussian function, σ is the standard deviation of the normal distribution, u is the position offset of the pixel on the x-axis, v is the position offset of the pixel on the y-axis, phase_blur is the phase after Gaussian blurring, and phase is the original phase after oversampling.

[0028] For example, performing Gaussian blurring on the perturbation phase distribution map to obtain the Gaussian-blurred phase distribution map includes:

[0029] The perturbation phase distribution map is first Gaussian blurred to obtain a first phase distribution map;

[0030] The first phase distribution map is subjected to a second Gaussian blur to obtain the Gaussian-blurred phase distribution map, wherein the parameter σ used in the first Gaussian blur and the parameter σ used in the second Gaussian blur are both greater than a preset value.

[0031] For example, the parameter σ used in the first Gaussian blur and the parameter σ used in the second Gaussian blur are both greater than 130nm.

[0032] For example, simulating the phase distribution map after Gaussian blurring and determining whether the simulation result meets the preset requirements includes:

[0033] The output light field after the input light passes through the target diffraction optical element is simulated using vector diffraction theory to obtain the simulated light field. The phase distribution of the target diffraction optical element is as shown in the phase distribution diagram after Gaussian blurring.

[0034] Determine whether the simulated light field meets the preset light field evaluation conditions. If it meets the preset light field evaluation conditions, the simulation result is determined to meet the preset requirements. If it does not meet the preset light field evaluation conditions, the simulation result is determined to not meet the preset requirements.

[0035] For example, the preset light field evaluation conditions include: the uniformity of the simulated light field is less than a first preset uniformity, or the number of times the loop is executed reaches a preset number.

[0036] For example, the simulation of the phase distribution map after Gaussian blurring includes:

[0037] The phase distribution map after Gaussian blurring is optimized using vector diffraction theory;

[0038] The optimized phase distribution map is simulated.

[0039] For example, the design method further includes:

[0040] The target light field of the emitted light after exiting from the diffractive optical element is obtained on the output surface, wherein the output surface and the diffractive optical element are spaced apart by a predetermined distance;

[0041] Based on the target light field, the initial phase distribution map of the diffractive optical element is designed and obtained using scalar diffraction theory.

[0042] According to a second aspect of the present invention, a diffractive optical element is provided, comprising:

[0043] The substrate and the microstructure formed on the substrate, wherein the microstructure is configured to split the emitted light emitted by the light source into multiple outgoing light beams, and the distribution of the microstructure on the substrate is formed by processing a target phase distribution map obtained according to the design method described above.

[0044] According to a third aspect of the present invention, a light projection device is provided, comprising:

[0045] A light source, used to emit light;

[0046] The diffractive optical element described above is disposed in the optical path of the emitted light from the light source, and is used to receive the emitted light emitted by the light source and split the emitted light emitted by the light source into multiple outgoing beams to project a light field onto the target surface.

[0047] According to a fourth aspect of the invention, an apparatus is provided that includes the light projection device as described above.

[0048] According to a fifth aspect of the present invention, a design system for a diffractive optical element is provided, comprising:

[0049] Memory is used to store executable program instructions;

[0050] One or more processors are configured to execute the program instructions stored in the memory, such that the processors perform the design method described above.

[0051] According to a sixth aspect of the present invention, a computer storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the design method described above.

[0052] According to the present invention, the diffractive optical element and its design method and system, light projection device, equipment and storage medium can make the phase distribution map edge more delicate by cyclically perturbing, Gaussian blurring and simulating until the simulation result meets the preset requirements, forming an approximately curved shape and reducing the sharp corner structure, making the diffractive optical element easier to process. Attached Figure Description

[0053] The following drawings, which are incorporated herein by reference and are used to understand this application, illustrate embodiments of the invention and their descriptions, thereby explaining the apparatus and principles of the invention. In the drawings,

[0054] Figure 1 A flowchart illustrating the design method for diffractive optical elements is shown.

[0055] Figure 2 A schematic diagram of the current phase distribution map to be processed is shown;

[0056] Figure 3 A schematic diagram of the pixels in the phase distribution map is shown;

[0057] Figures 4A-4D The diagrams show the current phase distribution map to be processed, the phase distribution map after the first Gaussian blur, the phase distribution map after the second Gaussian blur, and the energy distribution map of the light field points in the first loop process of the design method.

[0058] Figures 5A-5DThe diagrams show the current phase distribution map to be processed, the phase distribution map after the first Gaussian blur, the phase distribution map after the second Gaussian blur, and the energy distribution map of the light field points in the second loop process of the design method.

[0059] Figures 6A-6D The diagrams show the current phase distribution map to be processed, the phase distribution map after the first Gaussian blur, the phase distribution map after the second Gaussian blur, and the energy distribution map of the light field points in the third loop process of the design method.

[0060] Figures 7A-7D The diagrams show the current phase distribution map to be processed, the phase distribution map after the first Gaussian blur, the phase distribution map after the second Gaussian blur, and the energy distribution map of the light field points in the fourth iteration of the design method.

[0061] Figure 8 A schematic diagram of a diffractive optical element is shown.

[0062] Figure 9 A schematic block diagram of a light projection device is shown;

[0063] Figure 10 A schematic block diagram of a design system for a diffractive optical element is shown.

[0064] Explanation of reference numerals in the attached figures:

[0065] 10 - Continental block region, 11 - Interval region, 20 - Current pixel, 211, 212, 213, 214, 215, 216, 217, 218 - Neighboring pixels, 22, 23, 24, 25 - Pixels, 30 - Diffractive optical element, 31 - Substrate, 32 - Microstructure, 40 - Light projection device, 41 - Light source, 50 - Design system, 51 - Processor, 52 - Memory. Detailed Implementation

[0066] The following description provides numerous specific details to offer a more thorough understanding of this application. However, it will be apparent to those skilled in the art that this application can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described to avoid confusion with this application.

[0067] It should be understood that this application can be implemented in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this application to those skilled in the art.

[0068] It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or parts, these elements, components, areas, layers, and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or part from another element, component, area, layer, or part. Therefore, without departing from the teachings of this application, the first element, component, area, layer, or part discussed below may be referred to as the second element, component, area, layer, or part.

[0069] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0070] See attached document Figure 1 - Appendix Figure 7D The following is an exemplary description of a design method for a diffractive optical element according to an embodiment of this application. The design method includes the following steps:

[0071] S100: Obtain the current phase distribution map of the current loop process.

[0072] Specifically, when the current cycle is the first cycle, the current phase distribution map to be processed includes the initial phase distribution map of the diffractive optical element. When the current cycle is a cycle following the first cycle, the current phase distribution map to be processed includes the perturbed phase distribution map obtained in the previous cycle. In some embodiments, this phase distribution map is also referred to as a Manhattan map.

[0073] S200: Perturb the current phase distribution map to be processed to obtain a perturbed phase distribution map.

[0074] Specifically, see Appendix Figure 2 , attached Figure 2This diagram illustrates a current phase distribution map obtained through step S100 in one embodiment of this application. The current phase distribution map includes continental block regions 10 (shown as white in the diagram) and gap regions 11 located between adjacent continental block regions 10 (shown as black in the diagram). Continental block regions 10 consist of multiple consecutive pixels with the same logical value, and the logical value of each pixel in a continental block region 10 can be 1. Gap regions 11 are located between adjacent continental block regions 10 and consist of multiple consecutive pixels with the same logical value. The logical values ​​of gap regions 11 differ from those of continental blocks, and the logical value of each pixel in a gap region 11 can be 0. It should be noted that the current phase distribution map also includes isolated islands, which are single pixels with a logical value of 1 located within gap regions 11. The specific method for determining isolated islands will be explained in detail later and will not be elaborated here. It should be noted that the logical value here represents the presence or absence of an actual object. Specifically, in some embodiments, when the diffractive optical element is a two-step diffractive optical element, a logical value of 0 can indicate the absence of a step, and a logical value of 1 can indicate the presence of a step.

[0075] In some embodiments, the specific perturbation method in step S200 includes:

[0076] S210: Obtain the edge pixel located at the edge of continental block region 10, and set the logical value of the edge pixel to be the same as the logical value of the pixel within continental block region 10.

[0077] Specifically, in step S210, it is determined whether the logical values ​​of the eight neighboring pixels 211-218 surrounding the current pixel 20 with a logical value of 1 in the current phase distribution map are 0. Each pixel with a logical value of 1 in the current phase distribution map can be used as the current pixel 20 for determination. This pixel can be determined randomly, or each pixel with a logical value of 1 in the phase distribution map can be used as the current pixel 20 sequentially according to a preset order or rule. The eight neighboring pixels 211-218 are the eight pixels to the left, right, top, bottom, upper left, upper right, lower left, and lower right of the current pixel 20, surrounding it circumferentially. When at least one of the neighboring pixels 211-218 is not 0, it is then determined whether the logical values ​​of the next eight neighboring pixels 211-218 surrounding the current pixel 20 are 0. When the logical values ​​of neighboring pixels 211-218 are all 0, it is further determined whether the logical values ​​of at least four pixels located outside of neighboring pixels 211-218 (i.e., the side of neighboring pixels 211-218 that is far away from the current pixel 20) and adjacent to neighboring pixels 211-218 are 0. Among them, at least four pixels include four neighboring pixels 211, 215, 213, and 217 that are adjacent to the left, right, top, and bottom sides of the current pixel 20 and located on the side away from the current pixel 20. That is, these four pixels are: pixel 22 to the left of the neighboring pixel 211 to the left of the current pixel 20, pixel 23 to the right of the neighboring pixel 215 to the right of the current pixel 20, pixel 24 above the neighboring pixel 213 to the top of the current pixel 20, and pixel 25 below the neighboring pixel 217 to the bottom of the current pixel 20. When the logic value of at least one pixel located outside neighboring pixels 211-218 and adjacent to at least four pixels (e.g., at least one pixel among pixels 22, 23, 24, and 25) is not 0, then the neighboring pixel between the current pixel 20 and any of the at least four pixels with a non-zero logic value (e.g., any pixel with a logic value of 1 among pixels 22, 23, 24, and 25) is determined to be an edge pixel, and the logic value of that edge pixel is set to 1. After all current pixels 20 have been judged and processed, the final phase distribution map is the perturbation phase distribution map. See Appendix Figure 3In some embodiments, assuming the current pixel 20 has a logic value of 1, the logic values ​​of its eight neighboring pixels 211-218 are all 0, the logic value of pixel 22 to the left of the current pixel 20 is 1, and the logic values ​​of pixels 23, 24, and 25 to the right, top, and bottom of the current pixel 20 are all 0, then in step S210, the neighboring pixel 211 between the current pixel 20 and the pixel 22 to its left is determined to be an edge pixel, and this edge pixel is... The logical value of the current pixel 20 is set from 0 to 1, thus connecting the current pixel 20 to the continental block region. Similarly, when the logical values ​​of the neighboring pixels 211-218 within the eight-neighborhood of the current pixel 20 (which has a logical value of 1) are all 0, and the logical value of pixel 23 is 1, while the logical values ​​of pixels 22, 24, and 25 are all 0, then in step S210 above, the neighboring pixel 215 between the current pixel 20 and the pixel 23 located to its right is determined to be an edge pixel, and the logical value of this edge pixel is set from 0 to 1. Similarly, when the logic values ​​of neighboring pixels 211-218 within the eight-neighborhood of the current pixel 20 (logic value 1) are all 0, and the logic value of pixel 24 is 1, while the logic values ​​of pixels 22, 23, and 25 are all 0, then in step S210, the neighboring pixel 213 between the current pixel 20 and the pixel 24 above it is determined to be an edge pixel, and the logic value of this edge pixel is set from 0 to 1. Similarly, when the logic values ​​of neighboring pixels 211-218 within the eight-neighborhood of the current pixel 20 (logic value 1) are all 0, and the logic value of pixel 25 is 1, while the logic values ​​of pixels 22, 23, and 24 are all 0, then in step S210, the neighboring pixel 217 between the current pixel 20 and the pixel 25 below it is determined to be an edge pixel, and the logic value of this edge pixel is set from 0 to 1. Similarly, when the logic values ​​of neighboring pixels 211-218 within the eight-neighborhood of the current pixel 20 (which has a logic value of 1) are all 0, and the logic values ​​of pixels 22 and 23 are all 1, while the logic values ​​of pixels 24 and 25 are all 0, then in step S210 above, any one of the neighboring pixels 211 between the current pixel 20 and the pixel 22 to its left, and the neighboring pixels 215 between the current pixel 20 and the pixel 23 to its right, is determined to be an edge pixel. The logic value of this edge pixel (any one of the neighboring pixels 211 and 215) is set from 0 to 1.

[0078] In some embodiments, the specific perturbation method in step S200 includes:

[0079] S220: Obtain the isolated island and set its logical value to be the same as the logical value of the pixels in the island's neighborhood.

[0080] Specifically, in step S220, it is determined whether the logical values ​​of the eight neighboring pixels 211-218 surrounding the current pixel 20, which has a logical value of 1 in the current phase distribution map, are 0. This determination can be made for each pixel in the current phase distribution map with a logical value of 1. This pixel can be determined randomly, or it can be selected sequentially according to a preset order or rule. The eight neighboring pixels 211-218 are the eight pixels to the left, right, top, bottom, upper left, upper right, lower left, and lower right of the current pixel 20, surrounding it circumferentially. When at least one of the neighboring pixels 211-218 is not 0, it is then determined whether the logical values ​​of the next eight neighboring pixels 211-218 surrounding the current pixel 20 are 0. When the logical values ​​of neighboring pixels 211-218 are all 0, it is further determined whether the logical values ​​of at least four pixels located outside of neighboring pixels 211-218 (i.e., the side of neighboring pixels 211-218 that is far away from the current pixel 20) and adjacent to neighboring pixels 211-218 are 0. Among them, at least four pixels include four neighboring pixels 211, 215, 213, and 217 that are adjacent to the left, right, top, and bottom sides of the current pixel 20 and located on the side away from the current pixel 20. That is, these four pixels are: pixel 22 to the left of the neighboring pixel 211 to the left of the current pixel 20, pixel 23 to the right of the neighboring pixel 215 to the right of the current pixel 20, pixel 24 above the neighboring pixel 213 to the top of the current pixel 20, and pixel 25 below the neighboring pixel 217 to the bottom of the current pixel 20. When the logic values ​​of at least four pixels located outside and adjacent to neighboring pixels 211-218 (e.g., pixels 22, 23, 24, 25) are all 0, the current pixel 20 is determined to be an island, and its logic value is changed from 1 to 0 (i.e., set to the same logic value as the neighboring pixels of the current pixel 20). After all current pixels 20 have been judged and processed, the final phase distribution map is the perturbation phase distribution map. See Appendix. Figure 3In some embodiments, assuming that the logical value of the current pixel 20 is 1, the logical values ​​of the neighboring pixels 211-218 in the eight-neighborhood of the current pixel 20 are all 0, and the logical values ​​of pixels 22, 23, 24, and 25 to the left, right, top, and bottom of the current pixel 20 are all 0, then in the above step S220, the current pixel 20 is determined to be an island, and the logical value of the current pixel 20 is set from 1 to 0, so that the logical value of the island is the same as that of its neighboring pixels.

[0081] By using the above perturbation method, the degrees of freedom can be gradually increased during the perturbation process, transitioning from the edge to the global level. This allows the algorithm to converge relatively quickly and avoids the problem of being unable to optimize the mid-period due to excessively long vector calculation time.

[0082] S300: Gaussian blur the perturbation phase distribution map to obtain the Gaussian blurred phase distribution map.

[0083] Specifically, Gaussian blurring is a processing-friendly method for phase distribution maps. It can refine edges, forming an approximate curved shape and reducing sharp-edged structures, thus creating a smoother continental block structure, which is beneficial for processing. In this step, Gaussian blurring can be performed using the following formula:

[0084]

[0085]

[0086] Where G(u,v) is a two-dimensional Gaussian function, σ is the standard deviation of the normal distribution, u is the position offset of the pixel on the x-axis, v is the position offset of the pixel on the y-axis, phase_blur is the phase after Gaussian blurring, and phase is the original phase after oversampling.

[0087] Oversampling is performed during Gaussian blurring. Gaussian blurring is performed using the perturbed phase distribution map, which can effectively reduce the invalid solution space and achieve faster convergence.

[0088] In some embodiments, step S300 includes:

[0089] S310: Perform a first Gaussian blur on the perturbation phase distribution map to obtain the first phase distribution map.

[0090] S320: Perform a second Gaussian blur on the first phase distribution map to obtain the Gaussian blurred phase distribution map.

[0091] In this process, the parameter σ used in both the first and second Gaussian blurring is greater than a preset value, which can be 130 nm. The first Gaussian blur transforms the Manhattan phase map into an edge-smoothed phase distribution map. The second Gaussian blur allows for more refined design, resulting in a phase distribution map with richer edge and high-frequency information. This leads to better overall uniformity of the diffractive optical elements (such as two-dimensional gratings) fabricated based on this map, and the presence of more edge-smooth continental regions in the phase distribution map makes fabrication easier.

[0092] In some embodiments, Gaussian blurring may be performed only once in step S300.

[0093] S400: Simulate the phase distribution map after Gaussian blurring and determine whether the simulation result meets the preset requirements. If the determination is yes, proceed to step S500. If the determination is no, repeat steps S100-S400. That is, execute steps S100-S400 at least once until the simulation result meets the preset requirements.

[0094] Specifically, step S400 includes:

[0095] S410: The output light field after the input light passes through the target diffraction optical element is simulated using vector diffraction theory to obtain the simulated light field. The phase distribution of the target diffraction optical element is as shown in the phase distribution diagram after Gaussian blurring. In some embodiments, the simulated light field may include a point energy distribution diagram.

[0096] S420: Determine whether the simulated light field meets the preset light field evaluation conditions. If it meets the preset light field evaluation conditions, determine that the simulation result meets the preset requirements and proceed to step S500. If it does not meet the preset light field evaluation conditions, determine that the simulation result does not meet the preset requirements and repeat steps S100-S400. The preset light field evaluation conditions include: the uniformity of the simulated light field is less than a first preset uniformity, or the number of iterations of S100-S400 reaches a first preset number. The first preset uniformity can be the desired uniformity of the diffractive optical element to be processed. The first preset uniformity and the second preset number can be any suitable value reasonably set as needed, and are not specifically limited here.

[0097] In this application, the uniformity of the light field can be defined as U = (Imax - Imin) / (Imax + Imin), where I represents the light intensity at the signal point, Imax represents the maximum light intensity at the signal point, Imin represents the minimum light intensity at the signal point, and U represents the uniformity. Generally, the smaller the value of the uniformity U, the more uniform the light intensity distribution of the light field.

[0098] In some embodiments, step S400 includes:

[0099] S430: Optimize the phase distribution map after Gaussian blurring using vector diffraction theory. Specifically, those skilled in the art can further optimize the phase distribution map after Gaussian blurring using vector diffraction theory in any suitable manner, so that the uniformity of the output light field of the diffractive optical element corresponding to the optimized phase distribution map is better than the uniformity of the output light field of the diffractive optical element corresponding to the unoptimized phase distribution map.

[0100] S440: Simulate the optimized phase distribution map. Specifically, the optimized phase distribution map can be simulated through steps S410-S420, wherein the phase distribution of the target diffractive optical element in step S410 is as shown in the optimized phase distribution map.

[0101] S500: Obtain the target phase distribution map for fabricating diffractive optical elements. That is, use the Gaussian blurred phase distribution map that meets the preset requirements of the simulation results as the target phase distribution map for fabricating diffractive optical elements. This target phase distribution map is used to characterize the distribution of microstructures on the diffractive optical elements.

[0102] The target phase distribution map obtained through the above steps has good overall uniformity, and there are many continental block regions 10 with smooth edges on the phase distribution map, which makes it easier to process.

[0103] In some embodiments, the method further includes the following steps prior to step S100:

[0104] S100': Acquire the target light field on the output surface of the emitted light after exiting from the diffractive optical element, wherein the output surface and the diffractive optical element are spaced apart by a predetermined distance.

[0105] S110': Based on the target light field, the initial phase distribution map of the diffractive optical element is designed and obtained using scalar diffraction theory.

[0106] The target light field can be the desired target light field of the diffractive optical element (DOE) to be designed. The DOE projects the target light field onto its output surface at a predetermined distance (i.e., the design distance) from the DOE. The target light field can include the light field of a beam-splitting lattice. A beam-splitting lattice is a type of diffractive optical element (DOE) whose function is to split an incident laser beam into multiple uniform outgoing laser beams through diffraction based on a target diffraction pattern (a regular or irregular lattice). Depending on different application requirements, the predetermined distance between the output surface and the DOE can be different, and the target light field can have different shapes, sizes, target diffraction patterns, etc.

[0107] By designing diffractive optical elements based on the target light field, the actual light field formed by the designed diffractive optical elements during actual use is substantially consistent with the target light field. In step S110', any suitable method well known to those skilled in the art can be used to design and obtain the initial phase distribution map of the diffractive optical elements using scalar diffraction theory. For example, optimization algorithms such as the GS algorithm and its improved algorithms, the Yang-Gu (YG) algorithm and its improved algorithms, the simulated annealing algorithm (SA), the genetic algorithm (GA), and various hybrid algorithms can be used to obtain the initial phase distribution map of the diffractive optical elements.

[0108] In some embodiments, step S110' includes:

[0109] S111': Obtain the first input wavefront function of the input surface of the diffractive optical element. The first input wavefront function is determined based on a first estimated phase distribution and a preset input light amplitude distribution. The first estimated phase distribution can be a random phase distribution, and the method for determining this random phase distribution can be any suitable method, which can be determined based on the target light field. It is worth noting that the first input wavefront function in the first iteration is determined based on the first estimated phase distribution and the preset input light amplitude distribution. Optionally, the preset input light amplitude distribution can be determined based on information such as the intensity of the emitted light emitted by the light source to be modulated by the diffractive optical element.

[0110] S112': Perform a forward diffraction operation on the first input wavefront function to obtain a first output wavefront function of the output surface. The first output wavefront function includes the output light amplitude distribution and the output surface phase distribution; optionally, the forward diffraction operation can be based on, for example, the Fresnel diffraction formula or the Fraunhofer diffraction formula, to operate on the first input wavefront function.

[0111] S113': Modulate the output light amplitude distribution and update the first output wavefront function based on the modulated output light amplitude distribution to obtain the updated first output wavefront function. Optionally, the method for modulating the output light amplitude distribution can be any suitable modulation method, such as modulating the output light amplitude distribution through a target output light amplitude distribution, wherein the target output light amplitude distribution can be determined based on the designed target light field.

[0112] S114': Perform inverse diffraction on the updated first output wavefront function to obtain the second estimated phase distribution and the second input light amplitude distribution on the input surface. Optionally, the inverse diffraction operation is the inverse operation of the forward diffraction operation. For example, when the forward diffraction operation is based on the Fresnel diffraction formula, the inverse diffraction operation can be the inverse Fresnel diffraction formula. Similarly, when the forward diffraction operation is based on the Fraunhofer diffraction formula, the inverse diffraction operation can be the inverse Fraunhofer diffraction formula.

[0113] S115': Modulate the second input light amplitude distribution, and obtain a first input wavefront function for the next iteration based on the modulated second input light amplitude distribution and the second estimated phase distribution. Optionally, the method for modulating the second input light amplitude distribution can be any suitable method well known to those skilled in the art, for example, the second input light amplitude distribution can be modulated by the preset input light amplitude distribution in step S111'.

[0114] S116': Repeat steps S111' to S115' until the first iteration cycle termination condition is met, and output the second estimated phase distribution obtained in the last iteration as the initial phase distribution, and generate an initial phase distribution map based on this initial phase distribution. Optionally, the first iteration cycle termination condition includes at least one of the following conditions: the number of iterations (the number of times steps S111' to S115' are repeated) reaches a second preset number; the uniformity of the output light amplitude distribution is less than or equal to a second preset uniformity, wherein the second preset number and the second preset uniformity can be any suitable value reasonably set as needed, and are not specifically limited here. It is worth mentioning that after step S115' in each iteration process, it is determined whether the current iteration meets the first iteration cycle termination condition. If it does, the iteration stops, the second estimated phase distribution obtained in the current iteration is output as the first target phase distribution, and an initial phase distribution map is generated based on this initial phase distribution. If it does not meet the condition, the process returns to step S11 for the next iteration, until the first iteration cycle termination condition is met.

[0115] See attached document Figure 4A-7D The following is an exemplary description of a design method for a diffractive optical element according to an embodiment of this application.

[0116] See appendix Figures 4A-4D In the first iteration of the design method, an initial phase distribution map is obtained, as shown in the attached figure. Figure 4A As shown. Then, regarding the appendix... Figure 4A The initial phase distribution map shown is perturbed to obtain a first perturbed phase distribution map. Then, the first perturbed phase distribution map is subjected to a first Gaussian blur to obtain a phase distribution map after the first Gaussian blur, as shown in the attached figure. Figure 4B As shown. Then, regarding the appendix... Figure 4B The phase distribution map after the first Gaussian blur is shown. A second Gaussian blur is then performed to obtain the phase distribution map after the second Gaussian blur, as shown in the attached figure. Figure 4C As shown. Regarding the appendix Figure 4C The phase distribution map after the second Gaussian blur is shown in the figure. The resulting optical field point energy distribution map is attached. Figure 4DAs shown, the uniformity of the simulated light field is 85.3%, which does not meet the preset requirement of uniformity less than 15%, so a second cycle is performed.

[0117] See appendix Figures 5A-5D In the second cycle, the phase distribution diagram of the first disturbance (as shown in the attached diagram) is first analyzed. Figure 5A The phase distribution map (as shown) is perturbed to obtain a second perturbed phase distribution map. Then, a first Gaussian blur is applied to the second perturbed phase distribution map to obtain a phase distribution map after the first Gaussian blur, as shown in the attached figure. Figure 5B As shown. Then, regarding the appendix... Figure 5B The phase distribution map after the first Gaussian blur is shown. A second Gaussian blur is then performed to obtain the phase distribution map after the second Gaussian blur, as shown in the attached figure. Figure 5C As shown. Regarding the appendix Figure 5C The phase distribution map after the second Gaussian blur is shown in the figure. The resulting optical field point energy distribution map is attached. Figure 5D As shown, the uniformity of the simulated light field is 26.8%, which does not meet the preset requirement of uniformity less than 15%, so a third cycle is performed.

[0118] See appendix Figures 6A-6D In the third cycle, the second perturbation phase distribution diagram (as shown in the attached diagram) is first analyzed. Figure 6A The phase distribution map (as shown) is perturbed to obtain the third perturbed phase distribution map. Then, the third perturbed phase distribution map is subjected to the first Gaussian blur to obtain the phase distribution map after the first Gaussian blur, as shown in the attached figure. Figure 6B As shown. Then, regarding the appendix... Figure 6B The phase distribution map after the first Gaussian blur is shown. A second Gaussian blur is then performed to obtain the phase distribution map after the second Gaussian blur, as shown in the attached figure. Figure 6C As shown. Regarding the appendix Figure 6C The phase distribution map after the second Gaussian blur is shown in the figure. The resulting optical field point energy distribution map is attached. Figure 6D As shown, the uniformity of the simulated light field is 20.2%, which still does not meet the preset requirement of uniformity less than 15%, so the fourth cycle is performed.

[0119] See appendix Figures 7A-7D In the fourth cycle, the phase distribution diagram of the third disturbance (as shown in the attached diagram) is first analyzed. Figure 7A The fourth perturbation phase distribution map (as shown) is obtained by perturbing the fourth perturbation phase distribution map. Then, the fourth perturbation phase distribution map is subjected to the first Gaussian blur to obtain the phase distribution map after the first Gaussian blur, as shown in the attached figure. Figure 7B As shown. Then, regarding the appendix... Figure 7B The phase distribution map after the first Gaussian blur is shown. A second Gaussian blur is then performed to obtain the phase distribution map after the second Gaussian blur, as shown in the attached figure. Figure 7C As shown. Regarding the appendix Figure 7CThe phase distribution map after the second Gaussian blur is shown in the figure. The resulting optical field point energy distribution map is attached. Figure 6D As shown, the uniformity of the simulated light field is 13.5%, which meets the preset requirement of uniformity less than 15%, thus obtaining the target phase distribution map for fabricating diffractive optical elements, as shown in the attached figure. Figure 7C The phase distribution map shown is the result of the second Gaussian blurring. This target phase distribution map is used to characterize the distribution of microstructures on the diffractive optical element. The diffractive optical element can then be fabricated based on this target phase distribution map. The specific fabrication method is known to those skilled in the art and will not be described in detail here.

[0120] Furthermore, this application also provides a diffractive optical element designed based on the aforementioned design method, which will be referred to below. Figure 8 The diffractive optical element 30 is described below.

[0121] As an example, such as Figure 8 As shown, the diffractive optical element 30 of this application includes: a substrate 31 and a microstructure 32 formed on the substrate 31, wherein the microstructure 32 is configured to split the emitted light emitted by the light source into multiple outgoing light beams.

[0122] The substrate 31 can be any suitable material, such as glass. The microstructure 32 can be a protrusion on the surface of the substrate 31.

[0123] Microstructures corresponding to the target phase distribution map described above can be formed on the substrate 31 using any suitable method. For example, microstructures can be formed in the polymer by coating the substrate 31 with a polymer material and then imprinting it, or microstructures can be formed by etching the substrate 31.

[0124] Since the diffractive optical element 30 in this embodiment is designed based on the aforementioned design method, it has the same advantages as the aforementioned design method. The energy ratio of each beam splitting point after the emitted light from the light source is projected by the diffractive optical element 30 is consistent and more uniform. Furthermore, the diffractive optical element 30 is easier to process, thereby effectively reducing production costs.

[0125] Furthermore, this application also provides a light projection device, which may include the aforementioned diffractive optical element. Reference will now be made to... Figure 9 The light projection device 40 of this application will be described.

[0126] As an example, such as Figure 9 As shown, the light projection device 40 may include a light source 41 and the aforementioned diffractive optical element 30.

[0127] The light source 41 is used to emit light. Optionally, the light source 41 can be a laser emitter for emitting laser light.

[0128] The diffractive optical element 30 is disposed in the optical path of the emitted light of the light source 41, and is used to receive the emitted light emitted by the light source, split the emitted light emitted by the light source into multiple outgoing light beams, and modulate the high-frequency component of the light wave to project a light field on the target surface. The output light field has good uniformity.

[0129] The number of beams can be reasonably set during the design process according to actual needs. For example, the output light field energy distribution can be implemented as described in the aforementioned embodiment. Figure 7D The style shown.

[0130] In addition to the light source 41 and the diffractive optical element 30, the light projection device 40 may also include other optical systems, such as a collimating lens group. The collimating lens group can be disposed between the light source and the diffractive optical element 30 to collimate the emitted light from the light source.

[0131] The light projection device 40 of this application may also include other components, which are not specifically limited here. Since the light projection device of this application has the diffractive optical element 30 in the foregoing embodiment, it has the same advantages as the foregoing diffractive optical element 30.

[0132] Furthermore, this application embodiment also includes a device, which can be any device having the aforementioned light projection device 40, such as security equipment, terminal equipment, mobile platform equipment, etc. Terminal equipment may include, but is not limited to, mobile phones, tablets, laptops, desktop computers, etc., and mobile platform equipment may include, but is not limited to, vehicles, aircraft, ships, robots, etc., wherein vehicles may also be unmanned vehicles, etc.

[0133] Since the device of this application has the aforementioned light projection device 40, the energy distribution uniformity of the beam-splitting array projected by the light projection device 40 is good, thus improving the device's ability to detect and sense the environment.

[0134] This application also provides a design system for diffractive optical elements. This design system can be used as the execution subject of the aforementioned design method for diffractive optical elements. This design system can be implemented based on any computing device with data processing and computing capabilities, such as a desktop computer or a laptop.

[0135] As an example, see attached Figure 10 As shown, the design system 50 includes one or more processors 51, a display (not shown), a memory 52, and a communication interface (not shown), etc. These components are interconnected via a bus system and / or other forms of connection mechanisms (not shown). It should be noted that... Figure 10 The components and structures of the design system 50 shown are merely exemplary and not limiting; the design system 50 may also have other components and structures as needed.

[0136] Memory 52 is used to store various data and executable programs generated during the design process of diffractive optical elements, such as system programs, various application programs, or algorithms that implement various specific functions of design system 50. It may include one or more computer program products, which can include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. Volatile memory may include, for example, random access memory (RAM) and / or cache memory. Non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. Any data that needs to be stored locally in the design system can be stored in memory 52.

[0137] Processor 51 may be a central processing unit (CPU), a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other form of processing unit with data processing and / or instruction execution capabilities, and may control other components in the design system 50 to perform desired functions. For example, processor 51 may include one or more embedded processors, processor cores, microprocessors, logic circuits, hardware finite state machines (FSMs), digital signal processors (DSPs), graphics processing units (GPUs), or combinations thereof.

[0138] In one example, design system 50 also includes a communication interface (not shown) for communication between components within design system 50 and between components of design system 50 and other devices outside the system. The communication interface can be an interface using any known communication protocol, such as a wired or wireless interface. The communication interface may include one or more serial ports, USB interfaces, Ethernet ports, WiFi, wired networks, DVI interfaces, device interconnect modules, or other suitable ports, interfaces, or connections.

[0139] In one example, the design system also includes an input device (not shown), which can be a device used by a user to input instructions, and can include one or more of a keyboard, trackball, mouse, microphone and touch screen, or other input devices consisting of control buttons.

[0140] The design system of this invention also includes an output device that can output various information (e.g., images or sounds) to the outside (e.g., a user), and may include one or more of a display, a speaker, etc.

[0141] In this embodiment, the display of the design system can be a touch screen, an LCD screen, or a standalone display such as an LCD screen or television, independent of the design system. It can also be a display screen on an electronic device such as a mobile phone or tablet. The display can be used to show information input by the user or information provided to the user, as well as various graphical user interfaces of the design system. These graphical user interfaces can be composed of graphics, text, icons, video, and any combination thereof.

[0142] The processor 51 can be used to execute program instructions stored in memory, so that the processor can execute the design method of the diffractive optical element in this paper. The specific design method of the diffractive optical element can be referred to the previous description, and will not be repeated here.

[0143] In addition, embodiments of this application also provide a computer storage medium on which a computer program is stored. One or more computer program instructions may be stored on the computer-readable storage medium, and a processor may execute the program instructions stored in the storage device to implement the functions (implemented by the processor) in the embodiments of this application and / or other desired functions, such as performing corresponding steps of the design method for diffractive optical elements according to embodiments of this application. Various application programs and various data may also be stored in the computer-readable storage medium, such as various data used and / or generated by the application programs.

[0144] For example, the computer storage medium may include a memory card for a smartphone, a storage component for a tablet computer, a hard disk for a personal computer, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a portable compact disc read-only memory (CD-ROM), a USB memory, or any combination of the above storage media. The computer-readable storage medium may be any combination of one or more computer-readable storage media.

[0145] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of this application. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of this application. All such changes and modifications are intended to be included within the scope of this application as claimed in the appended claims.

[0146] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0147] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed.

[0148] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0149] Similarly, it should be understood that, in order to streamline this application and aid in understanding one or more of the various inventive aspects, features of this application may sometimes be grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of this application. However, this approach should not be construed as reflecting an intention that the claimed application requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, its inventive point lies in solving the corresponding technical problem with features fewer than all features of a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of this application.

[0150] Those skilled in the art will understand that, apart from the mutual exclusion of features, all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or elements of any method or apparatus so disclosed can be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature serving the same, equivalent, or similar purpose.

[0151] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0152] The various component embodiments of this application can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some modules according to the embodiments of this application. This application can also be implemented as an apparatus program (e.g., a computer program and computer program product) for performing part or all of the methods described herein. Such an implementation of this application can be stored on a computer-readable medium, or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

[0153] It should be noted that the above embodiments are illustrative of this application and not limiting of it, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. This application can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

Claims

1. A method for designing a diffractive optical element, characterized in that, include: Obtain the current phase distribution map to be processed in the current loop process, wherein when the current loop process is the first loop process, the current phase distribution map to be processed includes the initial phase distribution map of the diffractive optical element, and when the current loop process is a loop process after the first loop process, the current phase distribution map to be processed includes the perturbation phase distribution map obtained in the previous loop process before the current loop process; The current phase distribution map to be processed is perturbed to obtain a perturbed phase distribution map; Gaussian blurring is applied to the perturbation phase distribution map to obtain the Gaussian blurred phase distribution map; Simulate the phase distribution map after Gaussian blurring and determine whether the simulation results meet the preset requirements; The above steps are repeated at least once until the simulation result meets the preset requirements, thereby obtaining a target phase distribution map for processing the diffractive optical element. The target phase distribution map is a Gaussian blurring phase distribution map after the simulation result meets the preset requirements. The target phase distribution map is used to characterize the distribution of microstructures on the diffractive optical element.

2. The design method as described in claim 1, characterized in that, The current phase distribution map to be processed includes continental block regions and gap regions located between adjacent continental block regions; The step of perturbing the current phase distribution map to obtain a perturbed phase distribution map includes: Obtain the edge pixels located at the edge of the continental block region, and set the logical value of the edge pixels to be the same as the logical value of the pixels within the continental block region, and / or Identify isolated islands and set their logical values ​​to be the same as the logical values ​​of the pixels in their neighborhood.

3. The design method as described in claim 2, characterized in that, The step of obtaining edge pixels located at the edge of the continental block region and setting the logical values ​​of the edge pixels to be the same as the logical values ​​of pixels within the continental block region includes: Determine whether the logical values ​​of the neighboring pixels in the eight-neighborhood of the current pixel with a logical value of 1 in the current phase distribution map are 0, wherein the logical value of each pixel in the continental block region is 1, and the logical value of each pixel in the gap region is 0. When all the logical values ​​of the neighboring pixels are 0, it is determined whether the logical values ​​of at least four pixels located outside and adjacent to the neighboring pixel are 0. If the logical value of at least one of the at least four pixels is not 0, then the neighboring pixels between the current pixel and any of the at least four pixels with a non-zero logical value are determined as the edge pixel. Set the logical value of the edge pixel to 1.

4. The design method as described in claim 2, characterized in that, The step of acquiring isolated islands and setting the logical value of the isolated island to be the same as the logical value of the pixels in the island's neighborhood includes: Determine whether the logical values ​​of the neighboring pixels in the eight-neighborhood of the current pixel with a logical value of 1 in the current phase distribution map are 0, wherein the logical value of each pixel in the continental block region is 1, and the logical value of each pixel in the gap region is 0. When the logical values ​​of the neighboring pixels are all 0, determine whether the logical values ​​of at least four pixels located outside the neighboring pixels and adjacent to the neighboring pixels are 0. When the logical values ​​of the at least four pixels are all 0, determine that the current pixel is the island. Set the logical value of the isolated island to 0.

5. The design method as described in claim 3 or 4, characterized in that, The at least four pixels include four pixels that are adjacent to the four neighboring pixels to the left, right, top, and bottom of the current pixel and located on the side of the four neighboring pixels that are far away from the current pixel.

6. The design method as described in claim 1, characterized in that, The Gaussian blur is performed using the following formula: Where G(u,v) is a two-dimensional Gaussian function, σ is the standard deviation of the normal distribution, u is the position offset of the pixel on the x-axis, v is the position offset of the pixel on the y-axis, phase_blur is the phase after Gaussian blurring, and phase is the original phase after oversampling.

7. The design method as described in claim 6, characterized in that, The step of performing Gaussian blurring on the perturbation phase distribution map to obtain the Gaussian blurred phase distribution map includes: The perturbation phase distribution map is first Gaussian blurred to obtain a first phase distribution map; The first phase distribution map is subjected to a second Gaussian blur to obtain the Gaussian-blurred phase distribution map, wherein the parameter σ used in the first Gaussian blur and the parameter σ used in the second Gaussian blur are both greater than a preset value.

8. The design method as described in claim 7, characterized in that, The parameter σ used in the first Gaussian blur and the parameter σ used in the second Gaussian blur are both greater than 130nm.

9. The design method as described in claim 1, characterized in that, The simulation of the phase distribution map after Gaussian blurring, and the determination of whether the simulation results meet the preset requirements, includes: The output light field after the input light passes through the target diffraction optical element is simulated using vector diffraction theory to obtain the simulated light field. The phase distribution of the target diffraction optical element is as shown in the phase distribution diagram after Gaussian blurring. Determine whether the simulated light field meets the preset light field evaluation conditions. If it meets the preset light field evaluation conditions, the simulation result is determined to meet the preset requirements. If it does not meet the preset light field evaluation conditions, the simulation result is determined to not meet the preset requirements.

10. The design method as described in claim 9, characterized in that, The preset light field evaluation conditions include: the uniformity of the simulated light field is less than the first preset uniformity, or the number of times the loop is executed reaches a preset number.

11. The design method as described in claim 1, characterized in that, The simulation of the phase distribution map after Gaussian blurring includes: The phase distribution map after Gaussian blurring is optimized using vector diffraction theory; The optimized phase distribution map is simulated.

12. The design method as described in claim 1, characterized in that, The design method further includes: The target light field of the emitted light after exiting from the diffractive optical element is obtained on the output surface, wherein the output surface and the diffractive optical element are spaced apart by a predetermined distance; Based on the target light field, the initial phase distribution map of the diffractive optical element is designed and obtained using scalar diffraction theory.

13. A diffractive optical element, characterized in that, include: A substrate and microstructures formed on the substrate, wherein the microstructures are configured to split emitted light from a light source into multiple outgoing light beams, and the distribution of the microstructures on the substrate is formed by processing a target phase distribution map obtained according to the design method of any one of claims 1 to 12.

14. A light projection device, characterized in that, include: A light source, used to emit light; The diffractive optical element as described in claim 13 is disposed in the optical path of the emitted light of the light source, for receiving the emitted light emitted by the light source and splitting the emitted light emitted by the light source into multiple outgoing beams to project a light field onto the target surface.

15. A device, characterized in that, Includes the light projection device as described in claim 14.

16. A design system for a diffractive optical element, characterized in that, The design system includes: Memory is used to store executable program instructions; One or more processors are configured to execute the program instructions stored in the memory, such that the processors perform the design method as described in any one of claims 1 to 12.

17. A computer storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the design method as described in any one of claims 1 to 12.

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