An optimization design method of a polygon-based multi-plane device

Abstract

The application relates to an optimization design method of a polygon-based multi-plane device, comprising the following steps: S1. determining parameters of a polygon-based MPLC device; S2. constructing a topological-mode coupling model to determine a phase compensation amount; S3. generating an initial phase mask according to the phase compensation amount calculated in step S2 and in combination with phase distribution characteristics of a target mode; S4. outputting optimized phase mask parameters based on a genetic optimization algorithm; and S5. simulation verification: building simulation models of different topological structures, inputting the optimized phase mask parameters, simulating a mode evolution process, and analyzing whether a performance threshold value meets a demand. The application solves the problems that a traditional algorithm ignores the influence of a topological structure and the generality of a phase mask is poor, realizes accurate design of different polygon devices, and thus effectively reduces loss and improves shaping effect.

Description

Technical Field

[0001] This application relates to the field of multi-plane optical conversion technology, and more specifically, to an optimized design method for multi-plane devices based on polygons. Background Technology

[0002] Multiplane multiplexing / demultiplexing devices are based on multiplane optical conversion technology (MPLC). Their core function is to multiplex (combine) and demultiplex (separate) multiple independent optical signal modes in a mode-division multiplexing (MDM) system. During multiplexing, multiple optical signals are integrated into a single optical fiber for transmission; during demultiplexing, the signals are separated back into their original independent modes. This fully utilizes the multiple transmission modes of few-mode fibers, significantly improving the transmission capacity of a single fiber. Furthermore, they feature strong reconfigurability, low insertion loss, and low crosstalk, making them a key component of modern high-bandwidth communication networks.

[0003] The existing multiplane optical conversion technology is mainly divided into transmissive multiplane multiplexers and reflective multiplane multiplexers. (1) Transmissive multiplane multiplexer: The signal is transmitted directly through the multiplexer. Microwave transmission technology is used to realize the multiplexing and transmission of multiple signals in different planes (such as different frequencies and time slices). It is widely used in satellite communication, radar systems and wireless communication. However, multiple transmissions lead to increased signal energy loss; the cleanliness and angle accuracy of the transmission surface have a great impact on performance, and manufacturing and maintenance are complicated; it is easy to introduce additional crosstalk. (2) Reflective multiplane multiplexer: It integrates multiple optical signals by utilizing the principle of light reflection. It contains a reflector or a special optical thin film coating. It can guide optical signals from different input ports or wavelengths to the same output fiber through precise angle reflection. The optical path design is flexible and the wavelength selectivity is strong. It is suitable for scenarios requiring high-precision optical path control, such as dense wavelength division multiplexing (DWDM) systems. Light is shaped by back-and-forth reflections between the phase plate and the mirror. The phase is processed on a single phase plate. Increasing the phase requires increasing the number of reflections, which leads to increased loss. Too few reflections will affect the shaping effect. The angle and spacing between the mirror and the phase plate both affect the mode output. Stability needs to be reinforced after debugging. The cleanliness of the reflective surface and the angular accuracy have a significant impact on performance. Manufacturing and maintenance are complex. It is also easy to introduce additional crosstalk. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing reflective multiplane multiplexers in terms of loss and shaping effect, and to provide an optimized design method for multiplane devices based on polygons, which effectively reduces loss and improves shaping effect.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0006] An optimization design method for multi-planar devices based on polygons is provided, including the following steps:

[0007] S1. Determine the parameters of the polygon-based MPLC device, including topology parameters, target transmission mode, and performance thresholds; where topology parameters include the number of polygon faces N, the angle between adjacent phase planes θ, and the distance between adjacent phase planes d; performance thresholds include insertion loss IL and modal purity factor P.

[0008] S2. Construct a topology-modal coupling model and determine the phase compensation amount:

[0009] Based on the principles of geometric optics, the modal evolution path of the beam within the target topology is calculated, and the model parameters, including the number of reflections, the incident angle of each phase plane, and the total optical path, are determined.

[0010] Establish a topology-modal coupling model: ,in This represents the total phase accumulation. Indicates wave number, , The operating wavelength;

[0011] Based on the modal evolution path, model parameters, and topology-modal coupling model, determine the amount of phase compensation that the phase mask needs to provide;

[0012] S3. Determine the initial phase mask: Based on the phase compensation amount calculated in step S2, and combined with the phase distribution characteristics of the target mode, generate the initial phase mask;

[0013] S4. Output the optimized phase mask parameters based on the genetic optimization algorithm; where the fitness function in the genetic optimization algorithm is expressed as: , , , These are the weighting coefficients;

[0014] S5. Simulation Verification: Build simulation models with different topologies, input the optimized phase mask parameters, simulate the modal evolution process, and analyze whether the performance threshold meets the requirements. If not, return to step S2, adjust the model parameters, and continue until the target design requirements are met.

[0015] This invention provides an optimization design method for multi-planar devices based on polygons. Addressing the differences in modal evolution across different polygon topologies, it integrates a topology-modal coupling model with an improved genetic algorithm to form a collaborative process of "topology parameter input - modal evolution modeling - phase mask optimization." This solves the problems of traditional algorithms neglecting the influence of topology and having poor phase mask versatility, enabling precise design of devices with different polygon topologies, thereby effectively reducing losses and improving shaping performance.

[0016] Furthermore, based on the differences in modal evolution paths of different polygonal topologies, topology partitioning and mode-specific etching methods are used to etch the phase surface. This includes dividing the phase surface into a core control region and a topology adaptation region according to the incident angle and spot distribution of the beam on each phase surface, combined with topology parameters, including the angle and spacing between phase surfaces. The core control region etches the target modal phase pattern, and the topology adaptation region etches the phase compensation amount that matches the topology structure, thereby ensuring the mode conversion efficiency and stability of MPLC devices with different topologies.

[0017] Furthermore, considering the differences in loss sources among different polygonal topologies, a topology-differentiated compensation strategy is adopted to provide differentiated compensation for different topologies in order to reduce losses.

[0018] Furthermore, for quadrilateral MPLC devices, the reflection phase surface is divided into an LG mode core region and a right-angle adaptation region based on the number of reflections. The target mode phase pattern is etched in the LG mode core region, and the phase compensation amount is etched in the right-angle adaptation region to offset the phase abrupt change caused by the 90° angle. A phase gradient transition region is set between the LG mode core region and the right-angle adaptation region, and the phase change rate of the phase gradient transition region is less than or equal to 0.04 rad / μm.

[0019] Etching anti-reflection textures onto the transmission phase surface, texture period ),depth , is the refractive index.

[0020] Furthermore, for the pentagonal MPLC device, the reflection phase surface is divided into an LG01 mode core region, an LG10 mode core region, and a 108° angle adaptation region based on the number of reflections. The LG01 and LG10 mode core regions are etched with corresponding target mode phase patterns, and the 108° angle adaptation region is etched with phase compensation amounts. Anti-reflection etching areas are also set at the edges of each phase surface, with texture periods... To reduce edge reflection loss, The refractive index;

[0021] Etching anti-reflection textures onto the transmission phase surface, texture period ),depth At the same time, a preset phase correction value is superimposed to balance transmission and reflection losses.

[0022] Furthermore, for heptagonal MPLC devices, the reflection phase surface is divided into four multimode core regions and a long optical path adaptation region according to the number of reflections. The four multimode core regions are etched in parallel using multiple modes, which can adapt to the transmission of 2 to 8 target modes. The long optical path adaptation region is etched with phase compensation to offset the phase attenuation caused by the long optical path. Phase locking textures are also etched on each phase surface. The phase locking textures have a period of 1 μm and a depth of 200 nm to enhance the modal stability under long optical path.

[0023] Etching anti-reflection textures onto the transmission phase surface, texture period ),depth Meanwhile, a loss suppression phase pattern is added to the long optical path adaptation region to reduce cumulative reflection loss.

[0024] Furthermore, based on the differences in environmental sensitivity of different polygon topologies, environment-modal drift correlation models for different topologies are established, thereby dynamically adjusting environmental parameters according to different topologies; the environment-modal drift correlation models for different topologies are expressed as follows:

[0025] In the formula, For temperature changes, For vibration displacement, This is the phase shift amount. This is the temperature correction factor. This is the displacement correction factor.

[0026] Furthermore, the polygonal MPLC device includes a polygonal glass block, on which transmissive phase surfaces and reflective phase surfaces are etched according to design requirements on each face of the polygonal glass block; a miniature temperature sensor for collecting the temperature of the polygonal glass block, a vibration sensor for collecting the vibration displacement of the polygonal glass block, and a piezoelectric ceramic fine-tuning unit for adjusting the position of the phase surfaces are integrated on the edge of the polygonal glass block.

[0027] Furthermore, for quadrilateral MPLC devices, in the environment-modal drift correlation model, , For pentagonal MPLC devices, in the environment-modal drift correlation model, , For heptagonal MPLC devices, in the environment-modal drift correlation model, , .

[0028] Furthermore, the temperature and vibration displacement of the polygonal glass block are collected in real time by temperature and vibration sensors. The corresponding environment-mode drift correlation model is called according to different topologies to calculate the phase drift. For quadrilateral MPLC devices, the optical path offset caused by vibration displacement is compensated by adjusting the position of the phase surface. For pentagonal MPLC devices, the position of the phase surface and the equivalent phase of the phase mask are adjusted simultaneously to balance the effects of temperature and vibration. For heptagonal MPLC devices, the temperature phase drift under long optical path is compensated by adjusting the equivalent phase of the phase mask and the angle of the phase surface.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] The present invention provides an optimization design method for multi-planar devices based on polygons, which solves the problems of traditional algorithms ignoring the influence of topology and having poor versatility of phase masks. It enables precise design of different polygonal devices, thereby effectively reducing losses and improving shaping effect. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of an optimization design method for a polygon-based multi-planar device in one embodiment;

[0032] Figure 2 This is a schematic diagram of a quadrilateral MPLC device structure in one embodiment;

[0033] Figure 3 This is a schematic diagram of a pentagonal MPLC device structure in one embodiment;

[0034] Figure 4 This is a schematic diagram of a heptagonal MPLC device structure in another embodiment.

[0035] In the attached diagram: 100, glass block; 200, fiber optic array; 300, collimator. Detailed Implementation

[0036] The present invention will be further described below with reference to specific embodiments. The accompanying drawings are for illustrative purposes only, representing schematic diagrams rather than actual physical objects, and should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0037] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0038] Example 1

[0039] This embodiment is an example of a polygonal MPLC device, and several polygonal MPLC devices are provided in this embodiment; such as... Figure 2 As shown, this embodiment provides a quadrilateral MPLC device that uses a reflective multiplane multiplexing method. The core is a complete quadrilateral glass block 100, i.e., a glass block 100 with a regular quadrilateral prism structure. Phase surfaces 11 and 14 are transmissive phase surfaces, and phase surfaces 12 and 13 are reflective phase surfaces, all coated with a gold film. Supporting components also include an optical fiber array 200, a collimator 300, optical fiber jumpers, etc. The light beam enters from a specific angle into the glass block 100, undergoes multiple reflections and phase shaping within the glass block 100, and outputs the target mode. The distance between the reflector and the phase surface, the pitch of the phase surface, and the horizontal and vertical angles are fixed upon completion of the manufacturing process. Specific structural parameters, such as the distance between the reflector and the phase surface, the width of the phase surface, and the incident angle, need to be designed according to actual requirements.

[0040] like Figure 3 The figure shows a pentagonal MPLC device provided in this embodiment. Other components, such as the fiber array 200 and collimator 300, are omitted in the figure. The figure is mainly used to show the pentagonal glass block 100 and the optical path. The five faces of the pentagonal glass block 100 (a regular pentagonal prism structure) are respectively etched with phase surfaces. Among them, phase surfaces 21 and 24 are gold-plated on the back and are transmissive phase surfaces, used for the input and output of the optical path. Phase surfaces 22, 23, and 25 are all gold-plated on the back and are reflective phase surfaces. The output port of phase surface 24 is equipped with a coupler to connect the output mode to the optical fiber. The incident light is transmitted from phase surface 21 into the interior of glass block 100, directed towards phase surface 23, reflected by phase surface 23 to phase surface 25, reflected by phase surface 25 to phase surface 22, reflected by phase surface 22 to phase surface 24, and finally transmitted and output from phase surface 24, and connected to the optical fiber through the coupler.

[0041] like Figure 4As shown, this embodiment provides a heptagonal MPLC device. The heptagonal glass block 100 (a regular heptagonal prism structure) has seven etched phase surfaces on its seven sides. Phase surfaces 31 and 36 are unplated with gold film and are transmissive phase surfaces used for optical input and output. Phase surfaces 32, 33, 34, 35, and 37 have gold film on their back sides and are reflective phase surfaces. Output port 36 is equipped with a coupler for connecting the output mode to the optical fiber. Incident light is transmitted from phase surface 31 into the interior of the glass block 100, strikes phase surface 33, is reflected by 33 to phase surface 35, then reflected by 35 to phase surface 37, then reflected by 37 to phase surface 32, reflected by 32 to phase surface 34, and finally reflected by 34 to phase surface 36. The light is then transmitted from phase surface 36 and output, connecting to the optical fiber via the coupler.

[0042] The working principle of the polygonal MPLC device designed in this embodiment is similar: light passes through the fiber array 200, and a beam of light enters different channels. These different channels then direct the light onto phase plates. After beam shaping by multiple phase plates, the desired mode is finally output. Figure 2 As shown, an optical fiber array 200 is connected to the input end face to allow light to enter. The light beam is shaped by the phase plate designed in this invention, and finally, a coupler is connected to the output end to decompose the required mode.

[0043] Example 2

[0044] This embodiment is the first embodiment of an optimized design method for multi-plane devices based on polygons. This embodiment optimizes the design of the polygonal MPLC device provided in Embodiment 1, realizing a Laguerre-Gaussian (LG) mode separator based on multi-plane optical conversion (MPLC) technology. It employs a dual-core mechanism of "polygonal topology adaptation - mode evolution control." The core logic is reconstructed as follows: based on the topological structure of polygonal glass blocks 100 (quadrilateral, pentagonal, heptagonal), through deep coupling of topological parameters (number of faces, angle between adjacent faces, phase plane spacing) and mode evolution laws, efficient conversion from Gaussian spot array to the LG target mode is achieved. First, the mode evolution path is customized according to the optical path distribution and reflection / transmission path characteristics of the polygonal topology; then, the evolution process is precisely controlled through a phase mask to ensure that devices with different topologies can achieve low-loss, high-isolation mode conversion, while also considering the stability of the integrated structure and the adaptability of multiple topologies.

[0045] In this embodiment, the modal evolution path is the transmission and conversion trajectory of the light beam from the Gaussian spot to the LG mode within the polygonal MPLC device. This trajectory is determined by the polygonal topology parameters and manifests as a process of "Gaussian spot → segmented phase modulation → modal superposition → LG mode output". Different topologies correspond to different evolution paths (e.g., the evolution path of the heptagonal device contains 5 reflection modulations, and the pentagonal device contains 3 reflection modulations).

[0046] MPLC technology is a core technology for realizing beam spatial mode conversion through multi-phase masks. It is deeply adapted to polygonal topologies and matches the mode evolution path through segmented control of phase masks. It is the basis for devices to realize multiplexing / demultiplexing functions.

[0047] This embodiment presents an optimization design method for multi-planar devices based on polygons. It addresses the modal evolution differences of different polygon topologies by integrating a topology-modal coupling model with an improved genetic algorithm, forming a collaborative process of "topology parameter input - modal evolution modeling - phase mask optimization." This solves the problems of traditional algorithms neglecting the influence of topology and having poor phase mask versatility, enabling precise design of devices with different polygon topologies. Figure 1 As shown, the specific steps include:

[0048] Step S1. Determine the parameters of the polygon-based MPLC device, including topology parameters, target transmission mode, and performance thresholds. The topology parameters include the number of polygon faces N (quadrilateral N=4, pentagon N=5, heptagon N=7), the angle between adjacent phase planes θ (quadrilateral θ=90°, pentagon θ=108°, heptagon θ=128.57°), and the distance between adjacent phase planes d (derived from the polygon side length and angle). The topology parameters are the core parameters that determine the optical path length, number of reflections, and beam propagation direction, and directly affect the mode evolution efficiency. The performance thresholds include insertion loss IL, mode purity factor P, mode correlation loss MDL, and crosstalk XT.

[0049] In this step, the device topology type (quadrilateral / pentagon / heptagon) and corresponding topology parameters (e.g., pentagon N=5, θ=108°, side length 20mm), target transmission mode (e.g. LG01, LG10), and performance thresholds (IL≤1.5dB, XT≤-38dB, P≥99%) are first determined.

[0050] Insertion loss (IL): Combining the optical path loss and mode conversion loss of the polygonal topology, the calculation formula is as follows:

[0051]

[0052] in, For the number of patterns, These are the singular values ​​of the transfer matrix. The average optical path length (mm) for a single evolution path. The number of faces of the polygon.

[0053] Mode-dependent loss (MDL): Reflects the loss difference between different modes. Taking into account the influence of the angle between adjacent faces of a polygon, the calculation formula is as follows:

[0054]

[0055] in, , These are the maximum and minimum singular values, respectively. The phase plane angle corresponding to the target mode. It is the angle between the minimum phase planes.

[0056] Crosstalk (XT): Calculation of modal isolation characteristics based on polygonal topology, the core formula is:

[0057]

[0058] in, The coupling coefficients between modes, The phase plane clips are the phase plane clips corresponding to adjacent modes.

[0059] Modal purity factor (P): The calculation formula is as follows:

[0060]

[0061] in, For the actual output mode, For ideal mode, The number of faces in the polygon.

[0062] Step S2. Construct a topology-modal coupling model and determine the phase compensation amount:

[0063] Based on the principles of geometric optics, the modal evolution path of the beam within the target topology is calculated, and the model parameters, including the number of reflections, the incident angle of each phase plane, and the total optical path, are determined.

[0064] Establish a topology-modal coupling model: ,in This represents the total phase accumulation. Indicates wave number, , The operating wavelength;

[0065] Based on the modal evolution path, model parameters, and topology-modal coupling model, determine the amount of phase compensation that the phase mask needs to provide.

[0066] Step S3. Determine the initial phase mask: Based on the phase compensation calculated in step S2 and combined with the phase distribution characteristics of the target mode, an initial phase mask is generated. In this step, differentiated designs are implemented for different topologies: the phase mask for quadrilateral MPLC devices focuses on shortening optical path loss compensation, the phase mask for pentagonal MPLCs focuses on phase consistency control with multiple reflections, and the phase mask for heptagonal MPLCs focuses on maintaining modal stability under long optical path lengths.

[0067] Step S4. Output the optimized phase mask parameters based on the genetic optimization algorithm; where the fitness function in the genetic optimization algorithm is expressed as: , , , These are the weighting coefficients.

[0068] Chromosome encoding: The phase distribution parameters of the phase mask and the topological adaptation coefficients (such as optical path correction coefficients and angle adaptation coefficients) are binary encoded to form a chromosome vector;

[0069] Fitness function: Aiming at low loss, high purity, and topological fit, it is defined as follows: ,in , , To ensure that the optimization results are adapted to the target topology;

[0070] Iterative optimization: The roulette wheel selection, single-point crossover, and mutation operations are adopted, and the number of iterations is set to 120. Every 20 iterations, the topology parameters are fed back and corrected to ensure dynamic adaptation between the phase mask and the topology.

[0071] Termination condition: All performance thresholds are met for three consecutive iterations, and the optimized phase mask parameters are output.

[0072] S5. Simulation Verification: Build simulation models with different topologies, such as FDTD Solutions, input the optimized phase mask parameters, simulate the modal evolution process, and analyze whether the performance thresholds (analyze the insertion loss, crosstalk, modal purity, etc.) meet the requirements. If not, return to step S2 and adjust the model parameters until the target design requirements are met.

[0073] Example 3

[0074] This embodiment is a second embodiment of an optimization design method for polygonal multi-plane devices. This embodiment is similar to the second embodiment, except that in this embodiment, a suitable phase surface etching design is designed for different polygonal MPLC devices to improve the mode conversion efficiency and stability of the devices.

[0075] In this embodiment, firstly, based on the differences in modal evolution paths of different polygonal topologies, a topology partitioning + mode-specific etching strategy is adopted: according to the incident angle and spot distribution of the beam on each phase surface, combined with topology parameters (angle, spacing), the phase surface is divided into a core control area + a topology adaptation area. The core control area is etched with a mode-specific phase pattern, and the topology adaptation area is etched with a compensation phase that matches the topology structure, ensuring the mode conversion efficiency and stability of different topology devices. Secondly, considering the differences in loss sources of different polygonal topologies (quadrilaterals are mainly due to transmission loss, pentagons have a balance between transmission and reflection loss, and heptagons are mainly due to reflection loss), a topology differentiation compensation strategy is adopted: through active design of the phase mask, combined with topology parameters, targeted compensation for loss is achieved, reducing dependence on coating and lowering process complexity.

[0076] (1) For quadrilateral MPLC devices, the focus is on shortening the optical path loss compensation: The core topological characteristics of quadrilateral MPLC devices are that the number of faces N=4, the angle between adjacent faces θ=90°, the number of reflections is 2, and the total optical path is short (about 30mm). The optical path loss is mainly transmission loss (accounting for ≥60%). It is necessary to reduce the transmission loss in a targeted manner through phase mask design, while also compensating for the phase change caused by the 90° right angle. The specific implementation method is as follows:

[0077] 1. Design a topology-adaptive anti-reflection texture for the transmission phase surface: On the 11th and 14th transmission phase surfaces (non-gold-plated surfaces) of the quadrilateral glass block 100, an anti-reflection texture adapted to the 90° angle is etched, and the optical path loss is shortened by optimizing the texture parameters.

[0078] Texture Period and Depth Calculation: Combining quadrilateral right-angled topology (θ=90°), the anti-reflection texture period formula is customized as follows: (λ=1550nm is the working wavelength, n=1.5 is the glass refractive index), substituting θ=90°, we get: ;

[0079] Texture depth: .

[0080] Texture morphology: A square array of micro-nano textures is adopted, with the size and period of each texture unit matched. Electron beam lithography is used for etching, with an etching depth accuracy of ±5nm. This ensures that the reflectivity of the transmission interface is reduced from the conventional 4% to below 0.5%, reducing the single transmission loss by 0.15dB and the cumulative loss of two transmissions (11→14 phase plane) by 0.3dB, directly shortening the proportion of optical path loss.

[0081] 2. Design of a right-angle phase compensation area for the reflecting phase surface: The 12th and 13th reflecting phase surfaces (gold-plated surfaces) of the quadrilateral glass block 100 have a 90° reflection angle, which is prone to phase shift due to abrupt changes in the incident angle of the beam. Therefore, a right-angle phase compensation area needs to be added to the phase mask.

[0082] Partitioning: The reflective phase surface is divided into an LG mode core area (10×13mm) and a right-angle fitting area (7.5×13mm). The core area is etched with the target LG mode phase pattern (e.g., LG01 mode satisfies...). Distribution), the adaptation area is specially etched with a fixed phase compensation amount of 0.15 rad to offset the phase change caused by 90° reflection;

[0083] Transition Connection: A 30μm wide gradient transition zone is set between the core area and the adaptation area, with the phase change rate controlled at ≤0.04rad / μm to avoid additional loss introduced by phase abrupt changes, ensure the phase continuity of the reflected beam, and further reduce optical path loss.

[0084] (2) For pentagonal MPLC devices, the focus is on phase consistency control during multiple reflections: The core topological characteristics of pentagonal devices are: number of faces N=5, angle between adjacent faces θ=108°, 3 reflections (21→23→25→22→24), and a medium total optical path (approximately 45mm). The 3 reflections easily lead to phase accumulation deviation, requiring phase mask design to ensure phase consistency during multiple reflections. The specific implementation method is as follows:

[0085] 1. Phase consistency calibration texture design for reflective phase surfaces: On the 22, 23, and 25" reflective phase surfaces (gold-plated surfaces) of the pentagonal glass block 100, phase consistency calibration textures adapted to the 108° angle and three reflection paths are etched to quantitatively compensate for the phase deviation caused by the number of reflections.

[0086] Phase compensation calculation: based on the total phase accumulation formula (k=2π / λ, d=15mm is the distance between adjacent phase planes), substituting N=3 (number of reflections) and θ=108°, we get the phase deviation that needs to be compensated for in a single reflection as follows: ;

[0087] Texture etching: Periodically calibrated textures are etched at the edge region (1 mm wide) of each reflection phase surface. The phase depth of the texture unit is designed to be 0.2 rad and is finely adjusted with the number of reflections (0.18 rad compensation for the 23→25 phase surface in the first reflection, 0.2 rad compensation for the 25→22 phase surface in the second reflection, and 0.22 rad compensation for the 22→24 phase surface in the third reflection), ensuring that the total phase deviation after 3 reflections is ≤0.03 rad, thus achieving phase consistency.

[0088] 2. Bidirectional Phase Correction for Transmission Phase Surface Design: The 21st and 24th transmission phase surfaces of the pentagonal glass block 100 need to simultaneously connect the incident and outgoing beams. A phase mask is required to correct the phase connection deviation between transmission and reflection.

[0089] Incident end (21 phase surface): Etched pre-phase modulation texture, applying a phase shift of 0.05 rad in advance when the Gaussian spot is incident, so that the phase of the beam when it is incident on the 3 reflection phase surface matches the reflection compensation texture, avoiding the phase change of the first reflection;

[0090] Emitter end (24 phase surface): After etching, phase calibration texture is applied. Based on the phase detection results after reflections from 22 to 24, a phase correction amount of 0.05 rad is applied in reverse to ensure that the phase deviation between the final emitted LG mode and the ideal mode is ≤0.02 rad, further enhancing the phase consistency of multiple reflections.

[0091] 3. Design the phase-matching interface for the coupler:

[0092] On the surface of the coupler with 24 output ports, a phase-matching interface is etched to match the phase distribution of the reflection phase surface on the pentagonal glass block 100. Interface parameters: The central area of ​​the coupler lens (5mm in diameter) is etched with micro-nano textures corresponding to the output phase of the 24 phase surfaces. The texture phase depth is consistent with the compensation amount of the reflection phase surface (0.2rad) to ensure that the phase of the beam received by the coupler lens matches the phase of the fiber mode and avoids the amplification of phase deviation after multiple reflections in the coupling stage.

[0093] (3) For heptagonal MPLC devices, the focus is on designing for maintaining modal stability over long optical paths: The core topological features of heptagonal MPLC devices are: number of faces N=7, angle between adjacent faces θ=128.57°, number of reflections 5 (31→33→35→37→32→34→36), and total optical path length (approximately 60mm). Long optical paths easily lead to modal diffusion and phase attenuation, requiring phase mask design to maintain modal stability. The specific implementation method is as follows:

[0094] 1. The reflective phase surface is designed with "modal locking texture". Modal locking textures are etched on the 32, 33, 34, 35, and 37 reflective phase surfaces (gold-plated surfaces) of the heptagonal glass block 100 to constrain modal diffusion over long optical paths through physical structure:

[0095] Texture morphology: A composite texture of concentric circles and radial grids is adopted. The period of the concentric circles is matched with the topological charge of the LG mode (e.g., the period of the LG01 mode = 20μm), and the radial grid spacing = 5μm, forming a mode constraint cavity to prevent mode diffusion caused by diffraction during long-path propagation of the beam.

[0096] Phase attenuation compensation: Based on the phase attenuation law of long optical path (0.05rad attenuation per 10mm optical path), attenuation compensation phase is added to the texture unit. As the optical path increases (from phase plane 31→33 to phase plane 34→36), the compensation amount increases from 0.05rad to 0.25rad to ensure the stability of the modal phase under long optical path.

[0097] 2. Long optical path anti-attenuation texture design on the transmission phase surface; On the 31st and 36th transmission phase surfaces (non-gold plated surfaces) of the heptagonal glass block 100, an anti-attenuation texture adapted to a 60mm long optical path is etched to reduce modal energy loss during transmission; Texture parameters: anti-reflection texture period (θ=128.57°), substituting, we get ,depth Meanwhile, an energy focusing structure (such as a microlens array with a focal length of 20mm) is added to the texture unit to refocus the diffused beam energy, ensuring that the modal energy loss is ≤0.3dB under long optical path and maintaining modal stability.

[0098] 3. Phase surface edge design of mode isolation grooves: Mode isolation grooves (0.5mm wide) are etched on the edges of all phase surfaces on the heptagonal glass block 100 to physically isolate interference between adjacent modes; Groove structure parameters: isolation groove depth = 2μm, width = 50μm, absorbent texture (reflectivity ≤ 0.1%) is etched inside the groove to prevent crosstalk between adjacent modes during long optical path transmission, ensure the purity of a single LG mode ≥ 99%, and further maintain mode stability.

[0099] Example 4

[0100] This embodiment is the third embodiment of an optimization design method for multi-plane devices based on polygons. This embodiment is similar to the second embodiment, except that in this embodiment, the environmental sensitivity of different polygon topologies varies (quadrilateral structures are rigid but have short optical paths, and environmental disturbances have a significant impact on the modes; heptagonal structures have long optical paths, good modal stability but weak rigidity). This embodiment achieves modal stability in dynamic environments by integrating an "environmental sensing-topology adaptation calibration" closed-loop system and combining the environmental sensitivity characteristics of different topologies.

[0101] First, a miniature temperature sensor (accuracy ±0.1℃), a vibration sensor (accuracy ±10nm), and a piezoelectric ceramic fine-tuning unit (displacement accuracy ±10nm) are integrated on the edge of the polygonal glass block 100. The control module has a built-in "topology-environment-modal" correlation model, which dynamically adjusts the calibration strategy according to the topology type. The temperature sensor, vibration sensor, and piezoelectric ceramic fine-tuning unit are all communicatively connected to the control module.

[0102] In this embodiment, based on the differences in environmental sensitivity of different polygon topologies, an environment-modal drift correlation model for different topologies is established, thereby dynamically adjusting environmental parameters according to different topologies; wherein the environment-modal drift correlation model for different topologies is expressed as follows:

[0103] In the formula, For temperature changes, For vibration displacement, This is the phase shift amount. This is the temperature correction factor. This is the displacement correction factor.

[0104] For quadrilateral MPLC devices: ; , It focuses on compensating for modal drift caused by vibration displacement.

[0105] For pentagonal MPLC devices: ; , It takes into account both temperature and vibration balance compensation.

[0106] For heptagonal MPLC devices: ; , It focuses on compensating for long optical path phase drift caused by temperature.

[0107] In this embodiment, the parameters of each device mentioned above... The value of is derived through a combination of theory (topological parameters + physical laws) and experiment (environmental simulation + precise fitting). Theoretical derivation ensures that the parameters do not deviate, and experimental calibration ensures that the parameters are accurate enough. The final value not only matches the topological characteristics (optical path, rigidity, included angle) of different polygons, but also adapts to environmental disturbance scenarios in actual applications.

[0108] Core theoretical formula: Phase drift is caused by both temperature-induced refractive index changes and vibration-induced optical path shifts. Combining the principles of geometric optics and thermo-optics, the fundamental correlation formula is derived:

[0109]

[0110] The key parameters are fixed, known values: (Common operating wavelengths for communication); The total optical path of the device is (quadrilateral ≈ 30mm, pentagon ≈ 45mm, heptagon ≈ 60mm, derived from the side lengths and included angles of the polygons). (Thermo-optic coefficient of quartz glass, an industry-recognized value); The angle between adjacent faces of a polygon (90° for quadrilaterals, 108° for pentagons, and 128.57° for heptagons, a geometrically fixed value).

[0111] Substitute the initial range into the calculation:

[0112] Taking a quadrilateral as an example: Substitute , Calculated initial range , initial range ;

[0113] pentagon ( , ): initial range , initial range ;

[0114] heptagon ( , ): initial range , initial range .

[0115] The second stage involves experimental calibration to accurately fit parameter values; an environmental simulation experimental platform is built, and the optimal value is locked from the initial range through single-factor testing and multi-factor verification.

[0116] Experimental equipment and samples: Environmental equipment: Temperature chamber (temperature control range -10) ~50 Accuracy ±0.1 Vibration table (displacement range 0-200nm, accuracy ±10nm); Test samples: 3 each of the processed quadrilateral, pentagonal and heptagonal devices (to ensure sample consistency); Detection equipment: phase meter (accuracy ±0.001rad), laser interferometer (to detect optical path offset).

[0117] Single-factor test (test separately) and ):

[0118] 1. Measurement Fixed vibration displacement = 0 (no vibration), temperature from -10 Gradually rise to 50 , every 5 Stay for 10 minutes to record phase drift. Through linear fitting The slope of the curve is... Measured values ​​(e.g., obtained by quadrilateral fitting) );

[0119] 2. Measurement Fixed temperature = 25 (At room temperature), the vibrational displacement was gradually increased from 0 to 200 nm, with a 5-minute pause at every 20 nm interval, and the phase drift was recorded. Through linear fitting The slope of the curve is... Measured values ​​(e.g., obtained by quadrilateral fitting) ).

[0120] Multi-factor validation (confirming the effectiveness of parameter combinations):

[0121] Simultaneously apply temperature and vibration disturbances (such as...) , Substitute the initially obtained and Calculate the theoretical phase drift value and compare it with the experimentally measured value. If the deviation is ≤0.005rad, the parameter is accurate; if the deviation is >0.005rad, fine-tune the parameter (e.g., the quadrilateral). Fine-tuned from 0.012 to 0.0125 rad / Then retest until the deviation meets the requirements.

[0122] Furthermore, in this embodiment, a calibration procedure for topology differences is provided:

[0123] 1. Real-time data acquisition by temperature and vibration sensors , The control module calls the corresponding associated model based on the device topology type to calculate the phase adjustment amount;

[0124] 2. For quadrilateral MPLC devices: drive the piezoelectric ceramic fine-tuning unit to adjust the phase plane position (adjustment range ±40nm) to compensate for the optical path offset caused by vibration displacement.

[0125] For pentagonal MPLC devices: the phase plane position (±30nm) and the phase mask equivalent phase (±0.02rad) are adjusted synchronously to balance the effects of temperature and vibration.

[0126] For heptagonal MPLC devices: focus on adjusting the equivalent phase of the phase mask (±0.03 rad), and supplement by adjusting the phase plane angle (±0.03°) to compensate for temperature phase drift over long optical paths.

[0127] Calibration period: 20ms for quadrilateral MPLC devices, 30ms for pentagonal MPLC devices, and 40ms for heptagonal MPLC devices to ensure modal stability under dynamic conditions.

[0128] The method provided in this embodiment is applicable when the temperature changes by -10°C. Up to 50 In environments with vibration displacement ≤100nm, the crosstalk variation of quadrilateral MPLC devices is ≤1.8dB, that of pentagonal MPLC devices is ≤1.5dB, and that of heptagonal MPLC devices is ≤1.2dB, all of which are far superior to the 5-8dB of existing technologies. At the same time, it is compatible with modular splicing expansion design, and the spliced ​​composite topology can achieve accurate calibration through model parameter fusion, further enhancing the versatility and environmental adaptability of the devices.

[0129] Example 5

[0130] This embodiment is the fourth embodiment of an optimization design method for multi-plane devices based on polygons. In this embodiment, a pentagonal MPLC device is used as an example; the optimization design method is similar to that in embodiments two to four.

[0131] (1) Design parameters:

[0132] Pentagonal glass block 100: made of high-transmittance quartz glass (transmittance ≥99.8%), with a side length of 20mm and a thickness of 15mm; the etched area of ​​phase surfaces 21 and 24 (transmission surfaces) is 15×15mm, with a phase accuracy of ±0.02rad; the gold-plated layer on the back of phase surfaces 22, 23, and 25 (reflection surfaces) is 50nm thick (reflectivity ≥99.5%), with an etched area of ​​15×15mm.

[0133] Partition etching: The 23 phase planes are divided into an LG01 mode region (7×15mm), an LG10 mode region (7×15mm), and a gradient transition region (1×15mm). The phase change rate of the transition region is 0.05 rad / μm; the phase distribution of the LG01 mode region satisfies... LG 10 The phase distribution of the mode region satisfies .

[0134] Loss compensation: Phase offset compensation for reflection phase surfaces 22, 23, and 25 ; 21, 24 transmission phase surface anti-reflection texture period ,depth .

[0135] Calibration unit: DS18B20 miniature temperature sensor (accuracy ±0.1℃), installed at the center of the side of glass block 100; P-887.91 piezoelectric ceramic fine-tuning unit (displacement range ±100nm, accuracy ±10nm), 4 units in total, installed at the four corners of glass block 100; control module uses STM32L431 microcontroller, sampling frequency 10Hz, calibration response time ≤100ms.

[0136] Module splicing: When adapting to 3 modes, the basic module (including phase surfaces 21, 23, and 24) is 20×15×15mm in size, and the expansion module (including phase surface 22) is 20×5×15mm in size; the positioning groove is 2mm deep and 15mm wide, and the optical adhesive is NOA61 (refractive index 1.5, shear strength ≥15MPa after curing).

[0137] (2) Processing steps:

[0138] 1. Pretreatment of glass block 100: The pentagonal glass block 100 is polished on both sides to a surface roughness of ≤0.01μm; ultrasonic cleaning is performed (cleaning agent is isopropanol, temperature 50℃, time 10min), and then dried for later use.

[0139] 2. Installation of temperature sensor and piezoelectric ceramic fine-tuning unit: A matching mounting groove (temperature sensor groove 2×2×5mm, piezoelectric ceramic groove 5×5×5mm) is made on the side of glass block 100. The temperature sensor and piezoelectric ceramic fine-tuning unit are fixed with epoxy glue (model EPO-TEK 353ND) and cured at 80℃ / 2h. The wires are led out through the miniature wiring groove on the side of glass block 100. The groove is 0.5mm wide and 0.3mm deep.

[0140] 3. Phase Etching: Electron beam lithography (equipment model JEOL JBX-9500FS) is used to etch corresponding phase patterns on phase surfaces 21 to 25: anti-reflection textures and basic phase patterns are simultaneously etched on phase surfaces 21 and 24, and phase patterns with a 0.2 rad offset are etched on phase surfaces 22, 23, and 25; etching depth accuracy is ±5 nm, and linewidth accuracy is ±0.1 μm.

[0141] 4. Gold plating treatment: A 50nm thick gold film is deposited on the back side of phase planes 22, 23, and 25 using vacuum evaporation technology (equipment model Kurt J.Lesker PVD75). The evaporation rate is 0.1nm / s, the vacuum degree is ≤5×10-5Pa, and the uniformity of the coating is ensured to be ±5%.

[0142] 5. Module Assembly (in modular design): Align the basic module and expansion module using the positioning slots, apply NOA61 optical adhesive with a thickness of 5μm; expose to ultraviolet light (wavelength 365nm, power 100mW / cm²). 2 After curing for 30 seconds, the optical path alignment deviation after splicing is detected using a laser interferometer (accuracy ±0.01mm) to ensure ≤0.1°.

[0143] 6. Control Module Integration: The STM32L431 microcontroller, power module, and drive circuit are soldered onto a PCB board with dimensions of 20×20×1.6mm. The temperature sensor and piezoelectric ceramic fine-tuning unit are connected to the PCB board via wires to form a closed-loop control. The control module is encapsulated with potting compound (Dow Corning SE4485) to avoid external interference.

[0144] 7. Component assembly: Fix the pentagonal glass block 100 in the positioning groove of the 60×80mm quartz base with UV adhesive; install the fiber array 200 and coupler lens, adjust the position so that the incident light is aligned with the center of the 21 phase plane and the outgoing light is aligned with the center of the coupler lens; connect the fiber optic patch cord and the power supply of the control module to complete the assembly.

[0145] (3) Testing and verification:

[0146] 1. Static performance test: Input optical signals in three modes: LG01, LG10, and LP02, with a wavelength of 1550nm and a power of 10dBm; Insertion loss was measured using an optical power meter (Agilent 8163B), and the result was 1.2dB; Crosstalk was measured using a spectrum analyzer (Yokogawa AQ6370D), and the result was -40dB; MDL was calculated using SVD analysis, and the result was 0.2dB, which meets the design requirements.

[0147] 2. Dynamic performance test: Under the conditions of temperature chamber (-10℃ to 50℃, heating rate 5℃ / h) and vibration table (frequency 10-1000Hz, displacement 100nm), the self-calibration function was enabled; the test results showed that the crosstalk change was ≤1.5dB throughout the temperature change, ≤1.8dB under vibration environment, and ≥6dB without self-calibration function, which verified the effectiveness of the self-calibration design.

[0148] 3. Long-term stability test: After 1000 hours of continuous operation, insertion loss and crosstalk were measured every 24 hours. The results showed that the maximum change in insertion loss was 0.15dB, the maximum change in crosstalk was 0.8dB, and the mode drift was 0.015rad, indicating excellent stability.

[0149] In summary, this embodiment designs the aforementioned polygonal glass blocks 100 (quadrilateral, pentagonal, and heptagonal) as a combination of "basic module + extension module". The basic module includes core phase surfaces (such as phase surfaces 21, 23, and 24 of the pentagonal device), and the extension module includes auxiliary phase surfaces (such as phase surfaces 22 and 25 of the pentagonal device). The modules are detachably spliced ​​using optical adhesive and positioning grooves. The positioning groove accuracy is controlled within ±0.01mm to ensure that the optical path alignment deviation after splicing is ≤0.1°. The module combination can be selected according to the number of target modes required. For example, when adapting to 3 modes, "basic module + 1 extension module" is used; when adapting to 5 modes, "basic module + 2 extension modules" is used. After the modules are spliced, they are cured with optical adhesive to form a complete polygonal structure. The subsequent workflow is consistent with the corresponding integrated device. This embodiment balances the stability of the integrated structure with the flexibility of customization, eliminating the need to reprocess the entire device for different number of modes, reducing customization costs, and shortening the adaptation cycle by 60%.

[0150] In summary, the present invention has the following advantages:

[0151] 1. A joint optimization process of "wavefront matching-customized particle swarm optimization algorithm" is proposed. By improving the mode adaptability initialization, multi-index weighted fitness function and dynamic termination condition, the problem of "poor adaptability and difficulty in balancing loss and shaping effect" in MPLC phase mask design is solved. Compared with traditional algorithms, the phase design efficiency is improved by 40% and the mode shaping success rate is improved by 30%.

[0152] 2. Design a "mode partitioning etching + gradient transition" structure for the polygonal phase surface, dividing a single phase surface into a multi-mode dedicated area and a low-loss transition area, breaking through the limitation of existing technologies where a single phase surface can only adapt to 1-2 modes, realizing parallel transmission of 2-8 modes, and improving mode isolation by 8-10dB.

[0153] 3. A loss-compensating phase mask design method is provided, which compensates for reflection loss by phase shift and replaces part of the coating by etching anti-reflection phase texture, reducing the number of coating layers by 1-2 layers, reducing the overall device loss by 0.3-0.8dB, and reducing the process cost by 20%.

[0154] 4. A detachable splicing structure of "basic module + expansion module" for polygonal devices was designed. High-precision splicing is achieved through positioning grooves and optical adhesive. The optical path deviation after splicing is ≤0.1°. It takes into account the stability of the integrated structure and the flexibility of customization. The adaptation cycle under different mode requirements is shortened by 60%.

[0155] 5. A new phase self-calibration design adapted to dynamic environments has been added, integrating a miniature temperature sensor and a piezoelectric ceramic fine-tuning unit to establish a temperature-vibration-phase drift correlation model, enabling real-time phase calibration under dynamic environments. In environments ranging from -10℃ to 50℃ and with vibration ≤100nm, the crosstalk variation is ≤2dB, significantly improving the device's environmental adaptability.

[0156] In the specific implementation of the above embodiments, the technical features can be combined in any non-contradictory way. For the sake of brevity, not all possible combinations of the above technical features are described. However, as long as the combination of these technical features is not contradictory, it should be considered to be within the scope of this specification.

[0157] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. An optimization design method for multi-planar devices based on polygons, characterized in that, Includes the following steps: S1. Determine the parameters of the polygon-based MPLC device, including topology parameters, target transmission mode, and performance thresholds; where topology parameters include the number of polygon faces N, the angle between adjacent phase planes θ, and the distance between adjacent phase planes d; performance thresholds include insertion loss IL and modal purity factor P. S2. Construct a topology-modal coupling model and determine the phase compensation amount: Based on the principles of geometric optics, the modal evolution path of the beam within the target topology is calculated, and the model parameters, including the number of reflections, the incident angle of each phase plane, and the total optical path, are determined. Establish a topology-modal coupling model: ,in This represents the total phase accumulation. Indicates wave number, , The operating wavelength; Based on the modal evolution path, model parameters, and topology-modal coupling model, determine the amount of phase compensation that the phase mask needs to provide; S3. Determine the initial phase mask: Based on the phase compensation amount calculated in step S2, and combined with the phase distribution characteristics of the target mode, generate the initial phase mask; S4. Output the optimized phase mask parameters based on the genetic optimization algorithm; where the fitness function in the genetic optimization algorithm is expressed as: , , , These are the weighting coefficients; S5. Simulation Verification: Build simulation models with different topologies, input the optimized phase mask parameters, simulate the modal evolution process, and analyze whether the performance threshold meets the requirements. If not, return to step S2, adjust the model parameters until the target design requirements are met. Based on the differences in modal evolution paths of different polygonal topologies, topology partitioning and mode-specific etching methods are used to etch the phase surface. This includes dividing the phase surface into a core control region and a topology adaptation region according to the incident angle and spot distribution of the beam on each phase surface, combined with topology parameters, including the angle and spacing between phase surfaces. The core control region etches the target modal phase pattern, and the topology adaptation region etches the phase compensation amount that matches the topology structure, thereby ensuring the modal conversion efficiency and stability of MPLC devices with different topologies. Insertion loss IL is calculated using the following formula: In the formula, For the number of patterns, These are the singular values ​​of the transfer matrix. The average optical path length of a single evolution path. The number of faces of the polygon; The modal purity factor P is calculated using the following formula: In the formula, For the actual output mode, This is the ideal mode.

2. The optimization design method for multi-planar devices based on polygons according to claim 1, characterized in that, To address the differences in loss sources across various polygonal topologies, a topology-differentiated compensation strategy is employed to provide differentiated compensation for different topologies, thereby reducing losses.

3. The optimization design method for multi-planar devices based on polygons according to claim 2, characterized in that, For quadrilateral MPLC devices, the reflection phase surface is divided into an LG mode core region and a right-angle adaptation region based on the number of reflections. The target mode phase pattern is etched in the LG mode core region, and the phase compensation amount is etched in the right-angle adaptation region to offset the phase abrupt change caused by the 90° angle. Furthermore, a phase gradient transition region is set between the LG mode core region and the right-angle adaptation region, and the phase change rate of the phase gradient transition region is less than or equal to 0.04 rad / μm. Etching anti-reflection textures onto the transmission phase surface, texture period ),depth , is the refractive index.

4. The optimization design method for multi-planar devices based on polygons according to claim 2, characterized in that, For a pentagonal MPLC device, the reflection phase surface is divided into an LG01 mode core region, an LG10 mode core region, and a 108° angle adaptation region based on the number of reflections. The LG01 and LG10 mode core regions are etched with corresponding target mode phase patterns, and the 108° angle adaptation region is etched with phase compensation. Furthermore, anti-reflection etching areas are set at the edges of each phase surface, with texture periodicity. To reduce edge reflection loss, The refractive index; Etching anti-reflection textures onto the transmission phase surface, texture period ),depth At the same time, a preset phase correction value is superimposed to balance transmission and reflection losses.

5. The optimization design method for multi-planar devices based on polygons according to claim 2, characterized in that, For heptagonal MPLC devices, the reflection phase surface is divided into four multi-mode core regions and a long optical path adaptation region according to the number of reflections. The four multi-mode core regions are etched in parallel using multiple modes, which can adapt to the transmission of 2 to 8 target modes. The long optical path adaptation region is etched with phase compensation to offset the phase attenuation caused by the long optical path. Phase-locking textures are etched on each phase surface. The phase-locking textures have a period of 1 μm and a depth of 200 nm to enhance modal stability over long optical paths. Etching anti-reflection textures onto the transmission phase surface, texture period ),depth Meanwhile, a loss suppression phase pattern is added to the long optical path adaptation region to reduce cumulative reflection loss.

6. The optimization design method for polygon-based multi-planar devices according to any one of claims 1 to 5, characterized in that, Based on the differences in environmental sensitivity of different polygon topologies, an environment-modal drift correlation model is established for different topologies, thereby dynamically adjusting environmental parameters according to different topologies; the environment-modal drift correlation model for different topologies is expressed as follows: In the formula, For temperature changes, For vibration displacement, This is the phase shift amount. This is the temperature correction factor. This is the displacement correction factor.

7. The optimization design method for multi-planar devices based on polygons according to claim 6, characterized in that, The polygonal MPLC device includes a polygonal glass block, on which transmissive phase surfaces and reflective phase surfaces are etched according to design requirements. A miniature temperature sensor for collecting the temperature of the polygonal glass block, a vibration sensor for collecting the vibration displacement of the polygonal glass block, and a piezoelectric ceramic fine-tuning unit for adjusting the position of the phase surfaces are integrated on the edge of the polygonal glass block.

8. The optimization design method for multi-planar devices based on polygons according to claim 7, characterized in that, For quadrilateral MPLC devices, in the environment-modal drift correlation model, , For pentagonal MPLC devices, in the environment-modal drift correlation model, , For heptagonal MPLC devices, in the environment-modal drift correlation model, , .

9. The optimization design method for multi-planar devices based on polygons according to claim 8, characterized in that, Temperature and vibration displacement of the polygonal glass block are collected in real time by temperature and vibration sensors. The phase drift is calculated by calling the corresponding environment-mode drift correlation model according to different topologies. For quadrilateral MPLC devices, the optical path offset caused by vibration displacement is compensated by adjusting the position of the phase surface. For pentagonal MPLC devices, the position of the phase surface and the equivalent phase of the phase mask are adjusted simultaneously to balance the effects of temperature and vibration. For heptagonal MPLC devices, the temperature phase drift under long optical path is compensated by adjusting the equivalent phase of the phase mask and the angle of the phase surface.

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