Method and system for analyzing and optimizing layout of multi-channel integrated optical filter channel crosstalk

Abstract

The present application belongs to the technical field of multi-channel integrated optical filter design, and relates to a multi-channel integrated optical filter channel crosstalk analysis and layout optimization method and system. It comprises: establishing a system-level ray tracing model, which takes non-sequential ray tracing as the underlying ray propagation solving mechanism; based on the system-level ray tracing model, the non-sequential ray tracing and region analysis are used to obtain the stray light coefficients in the corresponding detector regions of each channel and the energy contribution proportion of the stray light propagation path; according to the stray light coefficients and the energy contribution proportion, the layout of the optical filter channels is optimized; the optimized layout is re-performed non-sequential ray tracing to verify the optimization effect, and if the design index is met, the final layout is output, otherwise the last step is returned for iterative optimization. Based on the system-level tracing model, it is not dependent on the specific number of channels or spectral configuration, and has general applicability to various types of multi-channel integrated optical filters.

Description

Technical Field

[0001] This invention belongs to the field of multi-channel integrated filter design technology, specifically relating to a method and system for channel crosstalk analysis and layout optimization of multi-channel integrated filters. Background Technology

[0002] Multichannel integrated filters integrate multiple filter units with different spectral transmission or polarization characteristics near the focal plane of a detector, enabling multispectral, polarization, or spectral-polarization joint snapshot imaging. They offer advantages such as compact structure, light weight, no need for moving parts, and high imaging efficiency, and are widely used in aerospace remote sensing, space astronomy, machine vision, biomedical imaging, and polarization imaging. As imaging systems develop towards higher spatial resolution, higher spectral resolution, and higher polarization measurement accuracy, the number of channels in multichannel integrated filters is continuously increasing, while the size of the filter units is continuously decreasing. Due to factors such as filter surface reflection, detector diffuse reflection, multiple reflections from optical elements, and structural scattering, optical crosstalk easily occurs between channels, leading to decreased spectral purity, increased polarization measurement errors, and reduced imaging quality. Therefore, channel crosstalk has become a significant factor affecting the performance of multichannel integrated filters.

[0003] Currently, research on multi-channel integrated filters mainly focuses on the design of filter spectral film systems, optimization of coating processes, and image reconstruction algorithms. Channel layouts are typically arranged according to rules or experience. Existing stray light analysis instruments primarily target the front-end optical system to evaluate the stray light performance of lenses or the entire system, lacking a systematic analysis method for crosstalk between channels within a focal-plane multi-channel integrated filter. Currently, channel crosstalk performance is usually evaluated through prototype testing, making prediction and optimization difficult during the filter design phase. Existing technologies lack system-level channel crosstalk analysis methods for multi-channel integrated filters, making it impossible to accurately predict the crosstalk level of each channel during the design phase. Furthermore, existing analysis methods do not fully consider the influence of filter structural parameters, optical film characteristics, light incident angle, and filter operating position on channel crosstalk, resulting in discrepancies between analysis results and actual operating conditions. There is a lack of analysis methods targeting stray light propagation paths and their energy contributions, making it difficult to identify the main sources and formation mechanisms of various types of crosstalk. Finally, there is a lack of layout optimization methods based on channel crosstalk analysis results; filter layouts mainly rely on empirical design, making it difficult to obtain the optimal layout scheme. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for crosstalk analysis and layout optimization of multi-channel integrated filters, in order to solve the technical problems of existing technologies that rely on prototype testing, do not fully consider the actual working state of the filters, lack methods for analyzing stray light paths and energy contributions, and lack layout optimization methods based on crosstalk analysis results.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for channel crosstalk analysis and layout optimization of multi-channel integrated filters, comprising: A system-level ray tracing model is established, which uses non-sequential ray tracing as the underlying ray propagation solution mechanism. Based on the system-level ray tracing model, the stray light coefficient and the energy contribution ratio of the stray light propagation path within the corresponding detection area of ​​each channel are obtained through non-sequential ray tracing and region analysis. The filter channel layout is optimized based on the stray light coefficient and the energy contribution ratio of the stray light propagation path in the detection area of ​​each channel. The optimized layout is re-performed with non-sequential ray tracing to verify the optimization effect. If the design specifications are met, the final layout is output; otherwise, the process returns to the previous step to continue iterative optimization.

[0006] Optionally, the establishment of the system-level ray tracing model specifically involves: setting the geometric structure and spatial pose of the light source, front-end optical system, multi-channel integrated filter, detector and detector window to form a system physical model; based on the system physical model, setting the characteristics of the light source and the material properties and surface characteristics parameters of each optical element, and using non-sequential ray tracing as the underlying ray propagation solution mechanism to construct the system-level ray tracing model.

[0007] Optionally, the light source characteristics are mainly used to define the operating wavelength and incident angle range of the filter to match the actual working state of the filter.

[0008] Optionally, the optical characteristic parameters include reflectivity, transmittance, scattering characteristics, and polarization characteristics.

[0009] Optionally, when constructing the physical model of the system, if the arrangement of the front-end optical system is unknown, a flat glass plate is used to simulate forward ray tracing; if the arrangement of the front-end optical system is known, the actual optomechanical model is used for ray tracing.

[0010] Optionally, the specific method for obtaining the stray light coefficient and stray light propagation path energy contribution ratio within the corresponding detection area of ​​each channel through non-sequential ray tracing and region analysis is as follows: Calculate the total received energy and stray light energy within the detection area corresponding to each channel. The total received energy includes the imaging energy of this channel, the stray light energy of this channel, and the crosstalk energy of other channels. Calculate the stray light coefficient of each channel based on the total received energy and stray light energy. At the same time, perform ray path tracing on each stray light propagation path and statistically analyze the energy contribution ratio of different propagation paths.

[0011] Optionally, the methods for optimizing the filter channel layout include, but are not limited to, adjusting the channel spatial position, optimizing the channel adjacency relationship, increasing the isolation distance of high crosstalk channels, or adding light-blocking structures.

[0012] Optionally, the optimization of the filter channel layout can be performed manually or automatically using genetic algorithms, particle swarm optimization algorithms, simulated annealing algorithms, graph theory optimization algorithms, or artificial intelligence algorithms.

[0013] In a second aspect, the present invention provides a multi-channel integrated filter channel crosstalk analysis and layout optimization system, comprising: The model building unit is used to establish a system-level ray tracing model, which uses non-sequential ray tracing as the underlying ray propagation solution mechanism. The channel crosstalk analysis unit is used to obtain the stray light coefficient and the energy contribution ratio of the stray light propagation path within the corresponding detection area of ​​each channel based on the system-level ray tracing model through non-sequential ray tracing and region analysis. The layout optimization unit is used to optimize the filter channel layout based on the stray light coefficient and the energy contribution ratio of the stray light propagation path in the detection area corresponding to each channel. The optimization verification unit is used to re-perform non-sequential ray tracing on the optimized layout to verify the optimization effect. If the design target is met, the final layout is output; otherwise, it returns to the previous step to continue iterative optimization.

[0014] Optionally, in the model building unit, establishing a system-level ray tracing model specifically involves: setting the geometric structure and spatial pose of the light source, front-end optical system, multi-channel integrated filter, detector, and detector window to form a system physical model; based on the system physical model, setting the characteristics of the light source and the material properties and surface characteristics parameters of each optical element, and using non-sequential ray tracing as the underlying ray propagation solution mechanism to construct a system-level ray tracing model.

[0015] Optionally, in the channel crosstalk analysis unit, the specific method for obtaining the stray light coefficient and the energy contribution ratio of the stray light propagation path within the corresponding detection area of ​​each channel through non-sequential ray tracing and region analysis is as follows: Calculate the total received energy and stray light energy within the detection area corresponding to each channel. The total received energy includes the imaging energy of this channel, the stray light energy of this channel, and the crosstalk energy of other channels. Calculate the stray light coefficient of each channel based on the total received energy and stray light energy. At the same time, perform ray path tracing on each stray light propagation path and statistically analyze the energy contribution ratio of different propagation paths.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention introduces non-sequential ray tracing as the underlying solution mechanism into a system-level ray tracing model, enabling simulation analysis of channel crosstalk in multi-channel integrated filters under actual operating conditions during the design phase. This overcomes the shortcomings of traditional sequential tracing, which cannot effectively handle multiple reflections, scattering, and cross-channel coupling paths of stray light. Furthermore, by combining non-sequential ray tracing with region analysis, the stray light coefficient of each channel and the energy contribution ratio of its stray light propagation path are simultaneously obtained. This achieves both a quantitative assessment of channel crosstalk levels and the ability to trace the specific sources of various types of crosstalk. This allows for targeted adjustments to the channel spatial layout during the layout optimization phase based on a clear crosstalk mechanism, avoiding empirical trial and error. Moreover, by re-tracing and verifying the optimized layout and iterating according to design specifications, a functional closed loop of modeling, analysis, optimization, and verification is formed. Crosstalk performance prediction, optimization, and confirmation can be completed during the design phase without relying on physical prototypes, significantly shortening the design cycle and reducing development costs. Simultaneously, this method, based on a system-level ray tracing model, is not dependent on a specific number of channels or spectral configuration, possessing universal applicability to various types of multi-channel integrated filters.

[0017] Furthermore, by defining the geometry and spatial pose of the light source, front-end optical system, filters, detectors, and windows, a system physical model encompassing all optical path components is formed. This ensures that subsequent ray tracing analysis no longer treats the filters as isolated devices but places them within a complete operational chain including the front-end optical system and detectors. Based on this physical model, light source characteristic parameters and material properties of each optical element, as well as optical characteristic parameters such as surface reflection, transmission, scattering, and polarization, are set to ensure that the light response behavior of each optical interface is consistent with its actual coating or processing state. Simultaneously, non-sequential ray tracing is employed as the underlying solution mechanism, thereby endowing the model with dual realism at both the physical carrier level and the computational rule level. The system-level ray tracing model constructed in the above manner can reproduce the light transmission process of the filter in the actual installed state during the design stage, making the channel crosstalk analysis results more consistent with subsequent measurements. At the same time, since this construction method is based on the general optical element settings and does not depend on the specific configuration of a particular optical system, when applied to different front-end optical configurations or multiple types of filter designs, only the corresponding setting parameters need to be adjusted to reuse the same modeling framework. There is no need to redevelop the analysis model for each case, thus ensuring consistency and reproducibility in the modeling stage in different design tasks. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1This is a schematic diagram of the method flow according to an embodiment of the present invention; Figure 2 This is a flowchart illustrating Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the initial layout of the 9-channel spectral-polarization filter according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the main light crosstalk paths of the 9-channel spectral-polarization filter in an embodiment of the present invention; Figure 5 This is a schematic diagram of the optimized layout of the 9-channel spectral-polarization filter according to an embodiment of the present invention; Figure 6 This is a system structure block diagram according to an embodiment of the present invention. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0020] The following detailed description is exemplary and intended to provide further detailed explanation of the invention. Unless otherwise specified, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention.

[0021] See Figure 1 This application discloses a method for channel crosstalk analysis and layout optimization of multi-channel integrated filters, including: A system-level ray tracing model is established, which uses non-sequential ray tracing as the underlying ray propagation solution mechanism. Based on the system-level ray tracing model, the stray light coefficient and the energy contribution ratio of the stray light propagation path within the corresponding detection area of ​​each channel are obtained through non-sequential ray tracing and region analysis. The filter channel layout is optimized based on the stray light coefficient and the energy contribution ratio of the stray light propagation path in the detection area of ​​each channel. The optimized layout is re-performed with non-sequential ray tracing to verify the optimization effect. If the design specifications are met, the final layout is output; otherwise, the process returns to the previous step to continue iterative optimization.

[0022] This invention establishes a system-level model with non-sequential ray tracing as the underlying solution mechanism, which can comprehensively simulate the complex ray behavior of filters under actual working conditions, providing an accurate data foundation for channel crosstalk analysis and enabling crosstalk performance prediction during the design phase. Based on this, non-sequential ray tracing and region analysis are used to obtain the stray light coefficient and stray light energy contribution ratio of each channel, combining crosstalk levels with formation mechanisms to provide a clear basis for subsequent optimization, improving the targeting and efficiency of layout optimization. Furthermore, the channel layout is optimized based on the analysis results, and the optimization effect is verified by re-tracing, forming a closed-loop iterative design process, reducing the cost of prototype manufacturing and repeated testing. In addition, this method is not dependent on a specific number or configuration of channels and can be uniformly applied to the design optimization of various types of multi-channel integrated filters, exhibiting good versatility.

[0023] In some embodiments, establishing a system-level ray tracing model specifically involves: setting the geometric structure and spatial pose of the light source, front-end optical system, multi-channel integrated filter, detector, and detector window to form a system physical model; based on the system physical model, setting the light source characteristics and material properties and surface optical characteristic parameters of each optical element, and using non-sequential ray tracing as the underlying ray propagation solution mechanism to construct a system-level ray tracing model. By setting the geometric structure and spatial pose of the light source, front-end optical system, filter, detector, and window to form a system physical model, and setting the light source characteristics and material properties and surface characteristic parameters of each optical element based on this physical model, the constructed system-level ray tracing model is consistent with the actual working state in terms of geometry, optical properties, and optical path transmission. This provides a simulation platform that can realistically reflect the reflection, scattering, and cross-channel propagation process of light within the system for subsequent channel crosstalk analysis, ensuring the accuracy and reliability of the calculation of stray light coefficient and energy contribution ratio.

[0024] In some embodiments, the optical characteristic parameters include reflectivity, transmittance, scattering characteristics, and polarization characteristics. By setting reflectivity, transmittance, scattering characteristics, and polarization characteristics as optical characteristic parameters, the system-level ray tracing model can comprehensively characterize the actual physical behavior of light at the interfaces and structural surfaces of each channel of the filter. In particular, it accurately describes the polarization-dependent loss generated by the metal wire grid structure in the polarization channel and the surface reflection in the non-light-transmitting region, thus providing complete surface optical property input for channel crosstalk analysis and further improving the accuracy and reliability of stray light coefficient calculation and stray light path tracing results. In some embodiments, when constructing the system physical model, a flat glass plate is used to simulate forward-tracking rays when the front-end optical system layout is unknown, and the actual optomechanical model is used for ray tracing when the front-end optical system layout is known. By using a flat glass plate to simulate forward-tracking rays when the front-end optical system layout is unknown, and using the actual optomechanical model for ray tracing when the layout is known, the modeling process can establish a ray tracing model in advance without depending on the specific design state of the front-end system. At the same time, it can seamlessly switch to an accurate model after obtaining actual optomechanical data. This ensures the feasibility and flexibility of the scheme demonstration in the early stage of design, and also ensures the accuracy and continuity of the analysis results in the later stage of design verification, further improving the universal adaptability of this method in different design stages.

[0025] In some embodiments, the specific method for obtaining the stray light coefficient and the energy contribution ratio of the stray light propagation path within the corresponding detection area of ​​each channel through non-sequential ray tracing and region analysis is as follows: Calculate the total received energy and stray light energy within the detection area corresponding to each channel. The total received energy includes the imaging energy of this channel, the stray light energy of this channel, and the crosstalk energy of other channels. Calculate the stray light coefficient of each channel based on the total received energy and stray light energy. At the same time, perform ray path tracing on each stray light propagation path and statistically analyze the energy contribution ratio of different propagation paths.

[0026] By calculating the total received energy within the detection area of ​​each channel, along with its own imaging energy, stray light energy, and crosstalk energy from other channels, and defining the stray light coefficient of each channel as the ratio of stray light energy to total received energy, a quantitative evaluation of the channel crosstalk level was achieved. Simultaneously, by tracing the propagation paths of each stray light and statistically analyzing their energy contribution ratio, the main sources of crosstalk and their formation mechanisms for each channel were qualitatively identified. This combination of quantitative evaluation and qualitative analysis provides a dual basis for subsequent layout optimization, encompassing both the severity and specific causes of crosstalk, thereby enhancing the pertinence and effectiveness of optimization measures.

[0027] In some embodiments, the methods for optimizing the filter channel layout include, but are not limited to, adjusting the channel spatial position, optimizing the channel adjacency relationship, increasing the isolation distance of high crosstalk channels, or adding a light-blocking structure. By optimizing the filter channel layout using at least one of these methods, the optimization approach can be specifically selected based on the stray light coefficient and stray light source composition of each channel obtained in step two. This allows for physical blocking or attenuation of specific crosstalk paths identified through ray path tracing. Therefore, even under constraints such as a limited detector imaging area and the inability to further increase the channel spacing, the stray light crosstalk level between channels can still be effectively reduced, ensuring that the optimization measures match the actual crosstalk mechanism.

[0028] In some embodiments, the optimization of the filter channel layout is performed through manual analysis, or automatically through genetic algorithms, particle swarm optimization, simulated annealing, graph theory optimization, or artificial intelligence algorithms. By employing at least one of these methods—manual analysis or genetic algorithms, particle swarm optimization, simulated annealing, graph theory optimization, or artificial intelligence algorithms—the optimization process can rely on both human intervention and judgment based on engineer experience, and also utilize automatic optimization algorithms to perform efficient global searches for complex layout problems with multiple channels and multiple constraints, thereby avoiding local optima and reducing the cost of manual trial and error. The compatibility of multiple optimization approaches allows this method to flexibly adapt to design scenarios with different complexities and precision requirements, further enhancing its versatility and engineering practicality.

[0029] Example 1 See Figure 2 A method for analyzing and optimizing the crosstalk of multi-channel integrated filters, comprising: Step 1: Establish a system-level ray tracing model A non-sequential optical model including a light source, a front-end optical system, a multi-channel integrated filter, a detector, and a detector window is established. Optical characteristic parameters such as reflection, transmission, scattering, and polarization of each optical surface are set to construct a system-level ray tracing model that conforms to the actual working state of the filter.

[0030] Step 2: Channel Crosstalk Analysis Non-sequential ray tracing and region analysis are used to calculate the total received energy and stray light energy within the corresponding detection area of ​​each channel, and the stray light coefficient of each channel is calculated to achieve a quantitative evaluation of channel crosstalk.

[0031] Simultaneously, ray path tracing is performed on all stray light propagation paths, and the energy contribution ratio of different propagation paths is statistically analyzed to obtain the composition of the main stray light sources in each channel, thus achieving a qualitative analysis of channel crosstalk.

[0032] The total received energy of the detector's corresponding channel includes the imaging energy of this channel, the stray light energy of this channel, and the crosstalk energy of other channels.

[0033] Step 3: Layout Optimization Based on the analysis results of stray light coefficients and stray light sources in each channel, the filter channel layout is optimized, including but not limited to adjusting the spatial position of the channels, optimizing the channel adjacency relationship, increasing the isolation distance of high crosstalk channels or the light-blocking structure, in order to reduce channel crosstalk.

[0034] Step 4: Optimize and Verify An optimized system model is established, and non-sequential ray tracing is performed again to calculate the stray light coefficients of each channel after optimization, and the results are compared with those before optimization. When the design specifications are met, the final layout is output; otherwise, iterative optimization continues, forming a closed-loop design process of "analysis-optimization-verification".

[0035] Example 2 Take a 9-channel polarization-spectral integrated filter as an example. This filter contains 9 different functional channels, integrated in front of the detector focal plane, and its initial filter layout is as follows. Figure 3 As shown, the nine channels, from top to bottom, are: B2 spectral channel (center wavelength 555nm, bandwidth 70nm); B1 spectral channel (center wavelength 485nm, bandwidth 70nm); polarization channels P4-P1 (polarization directions 135°, 90°, 45°, 0° respectively); panchromatic P channel (center wavelength 675nm, bandwidth 450nm); spectral channel B3 (center wavelength 660nm, bandwidth 60nm); and spectral channel B4 (center wavelength 830nm, bandwidth 120nm). The polarization channels P1-P4 are protected by an adhesive bonding process to safeguard the etched polarization microstructures. Each channel has a width of 1.1mm, a spacing of 0.85mm between channels, a total filter thickness of 2mm, and a black opaque mask in the grid area. The design requires a stray light coefficient of <3% for the filter channels.

[0036] (1) First, a system-level optical model is established for the filter, the channel stray light coefficient of the original layout is calculated, and the sources of stray light in each channel are analyzed. Based on the analysis results, the spatial position of each channel is adjusted to separate the high crosstalk channels and optimize the adjacency relationship between different channels. The specific operation is as follows: The filter is located 0.75 mm in front of the focal plane window, with a maximum principal ray incident angle of 5° and a maximum peripheral ray incident angle of 8.6°. Since the specific arrangement of the front-end optical system is unknown, two flat glass plates are used in the simulation to represent the front-end optical elements for tracing the filter's forward rays. If the front-end optical system is known, it can be used in an actual optomechanical model for ray tracing. A 6500 K blackbody surface light source is used to simulate the continuous broadband illumination conditions and actual ray incident angle range during the filter's actual operation. The detector size is 36 mm × 27 mm, used to collect the arriving light energy. Material and surface properties are set for the filter, all optical elements, and the structural frame. Then, mega-ray tracing is initiated, and the stray light coefficients for each channel are calculated using the region analysis function, as shown in Table 1.

[0037] Table 1. Stray light coefficients for each channel

[0038] Through light path analysis, it can be seen that the main channel crosstalk path of this filter is as follows: Figure 4 As shown, the crosstalk paths include: ① Light from this channel is diffusely reflected by the detector and then reflected again into this channel; ② Light from other channels is diffusely reflected by the detector and then reflected by adjacent filters into this channel; ③ Light from other channels is reflected by filters and then reflected once or multiple times by the front-end optical elements into this channel; ④ Light blocked by a light-blocking mask is reflected by the mask and then reflected by the front-end optical elements into this channel; ⑤ Light from other channels is diffusely reflected by the detector and then reflected by the light-blocking mask into this channel. The above are just a few of the main crosstalk paths; the actual sources of crosstalk can vary depending on the filter type, film structure, and optical system configuration.

[0039] Among them, the reflection of the mask in the non-light-transmitting region of polarization channels P1 to P4 (i.e., Figure 4 Path ④ in the middle) and the reflection of light rays with polarization states orthogonal to their polarization transmission axis within the polarization channel (i.e. Figure 4 Path ③ in the image will cause light crosstalk to the polarization channel itself and adjacent spectral channels. This is because the polarization filter uses a subwavelength metal wire grid to achieve polarization selection. Its polarization function region is composed of a metal wire grid structure, and the non-transmitting region uses a metal aluminum film as a light-shielding layer. Since both the metal wire grid structure and the metal aluminum film have high reflectivity, they will generate strong reflected stray light. Due to limitations in device structure and processing technology, this part of reflected stray light is difficult to completely eliminate through process optimization. In order to minimize the crosstalk of the above stray light to the spectral channel, this embodiment adopts a layout in which the spectral channel and the polarization channel are physically isolated. Specifically, in order to ensure that the polarization channel is always located at the center of the filter's field of view, the filter structure frame is improved. The entire filter is designed as a three-piece independent structure, and two structural light-blocking strips are set between the polarization channel and the spectral channel to achieve physical isolation between the two, thereby effectively reducing the crosstalk of reflected stray light from the polarization channel to the spectral channel. Because the structural light-blocking strip is located within the system's field of view and close to the image plane, its surface reflection may further introduce stray light. Therefore, the surface of the light-blocking strip needs to be coated with black matte paint to reduce the impact of diffuse reflection on image quality. Additionally, the stray light coefficient of channel B4, which is separated from the panchromatic P channel, is relatively higher than other spectral channels. This is mainly due to crosstalk from the P band, and the crosstalk optical path is... Figure 4Path ②. Specifically, the 830nm spectrum corresponding to B4 can pass through the P panchromatic channel almost without loss. This portion of light, under the action of the B3 bandpass film system (corresponding to 660nm, this film system has high transmittance near the 660nm wavelength, but high reflectivity in the wavelength range outside the bandwidth, which is an inherent characteristic of spectral film systems), will be reflected almost without loss to the detector area corresponding to the B4 channel. Since the B1-B4 spectral bandpass films do not overlap with each other and are all covered by the P panchromatic band, this interference is inevitable. An effective way to reduce the interference of this path is to adjust the position of the P panchromatic channel so that there is only one adjacent spectral channel. In this embodiment, the positions of the P channel and the B1 channel have been adjusted.

[0040] For path ③, theoretically, increasing the width of the light-blocking mask could effectively improve the situation. However, the effective imaging area of ​​the detector is limited, making it impossible to further increase the spacing between channels. Finally, in this filter film system design, the mask near the focal plane is a black film with high absorptivity (up to 99%), thus minimizing the crosstalk effect of stray light in this area. Based on the above light path analysis and corresponding improvement measures, a new filter arrangement can be obtained, such as... Figure 5 As shown.

[0041] (2) Recalculate the ray tracing to obtain the optimized channel stray light coefficient.

[0042] To more intuitively demonstrate the effectiveness of the multi-channel filter layout optimization, the following table lists the comparison of stray light coefficients of each channel before and after the implementation of each improvement measure, see Table 2.

[0043] Table 2 Comparison of stray light coefficients for each channel

[0044] Adding structural barring significantly reduced the interference of polarization on the spectrum, and similarly, the interference of the spectrum on polarization was also mitigated to some extent. The average stray light coefficient of each channel decreased from 2.35% to 2.18%, but the stray light coefficient of channel B4 remained at a high level, indicating that the structure needed improvement. Only after swapping channels P and B1 did the stray light in channel B4 decrease dramatically, ultimately falling below the design target of 3%. At this point, the average stray light coefficient of each channel had been reduced to 2.06%. These results demonstrate that the stray light coefficient of each channel was significantly reduced after optimization, validating the effectiveness of the method described in this invention.

[0045] Example 3 This invention is not limited to the 9-channel polarization-spectral filter in Embodiment 2. It is applicable to multi-channel integrated spectral, polarization, and spectral-polarization combined filters of any number and any spectral band. Furthermore, this method is also applicable to filters with various integration methods, such as multi-piece splicing integration, monolithic integration, linear gradient integration, and metasurface integrated filters. In addition, the layout optimization method is not limited to manual analysis; it can also be combined with genetic algorithms, particle swarm optimization, simulated annealing, graph theory optimization, and artificial intelligence algorithms to achieve automatic layout optimization. Finally, the front-end optical system in this case uses two flat glass plates for simulation, primarily to demonstrate the effectiveness of the method. To improve the accuracy of the model, an actual optomechanical model can be used for analysis.

[0046] Example 4 like Figure 6 As shown, based on the same inventive concept as the above embodiments, the present invention also provides a multi-channel integrated filter channel crosstalk analysis and layout optimization system, comprising: The model building unit is used to establish a system-level ray tracing model, which uses non-sequential ray tracing as the underlying ray propagation solution mechanism. The channel crosstalk analysis unit is used to obtain the stray light coefficient and the energy contribution ratio of the stray light propagation path within the corresponding detection area of ​​each channel based on the system-level ray tracing model through non-sequential ray tracing and region analysis. The layout optimization unit is used to optimize the filter channel layout based on the stray light coefficient and the energy contribution ratio of the stray light propagation path in the detection area corresponding to each channel. The optimization verification unit is used to re-perform non-sequential ray tracing on the optimized layout to verify the optimization effect. If the design target is met, the final layout is output; otherwise, it returns to the previous step to continue iterative optimization.

[0047] In some embodiments, the establishment of a system-level ray tracing model in the model building unit specifically involves: setting the geometric structure and spatial pose of the light source, front-end optical system, multi-channel integrated filter, detector and detector window to form a system physical model; based on the system physical model, setting the light source characteristic parameters, material properties and surface characteristic parameters of each optical element, and using non-sequential ray tracing as the underlying ray propagation solution mechanism to construct a system-level ray tracing model.

[0048] In some embodiments, the specific method by which the stray light coefficient and the energy contribution ratio of the stray light propagation path within the corresponding detection area of ​​each channel are obtained in the channel crosstalk analysis unit through non-sequential ray tracing and region analysis is as follows: Calculate the total received energy and stray light energy within the detection area corresponding to each channel. The total received energy includes the imaging energy of this channel, the stray light energy of this channel, and the crosstalk energy of other channels. Calculate the stray light coefficient of each channel based on the total received energy and stray light energy. At the same time, perform ray path tracing on each stray light propagation path and statistically analyze the energy contribution ratio of different propagation paths.

[0049] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for analyzing and optimizing the crosstalk of multi-channel integrated filters, characterized in that, include: A system-level ray tracing model is established, which uses non-sequential ray tracing as the underlying ray propagation solution mechanism. Based on the system-level ray tracing model, the stray light coefficient and the energy contribution ratio of the stray light propagation path within the corresponding detection area of ​​each channel are obtained through non-sequential ray tracing and region analysis. The filter channel layout is optimized based on the stray light coefficient and the energy contribution ratio of the stray light propagation path in the detection area of ​​each channel. The optimized layout is re-performed with non-sequential ray tracing to verify the optimization effect. If the design specifications are met, the final layout is output; otherwise, the process returns to the previous step to continue iterative optimization.

2. The method for analyzing and optimizing the crosstalk of a multi-channel integrated filter channel according to claim 1, characterized in that, The establishment of the system-level ray tracing model specifically involves: setting the geometric structure and spatial pose of the light source, front-end optical system, multi-channel integrated filter, detector and detector window to form a system physical model; based on the system physical model, setting the characteristics of the light source and the material properties and surface characteristics parameters of each optical element, and using non-sequential ray tracing as the underlying ray propagation solution mechanism to construct the system-level ray tracing model.

3. The method for analyzing and optimizing the crosstalk of a multi-channel integrated filter channel according to claim 2, characterized in that, The light source characteristics are used to define the operating wavelength and incident angle range of the filter to match the actual working state of the filter; the optical surface characteristic parameters include reflectivity, transmittance, scattering characteristics and polarization characteristics.

4. The method for analyzing and optimizing the crosstalk of a multi-channel integrated filter channel according to claim 2, characterized in that, When constructing the physical model of the system, if the arrangement of the front-end optical system is unknown, a flat glass plate is used to simulate forward ray tracing. If the front-end optical system is known, the actual optomechanical model is used for ray tracing.

5. The method for analyzing and optimizing the crosstalk of a multi-channel integrated filter channel according to claim 1, characterized in that, The specific method for obtaining the stray light coefficient and stray light propagation path energy contribution ratio within the corresponding detection area of ​​each channel through non-sequential ray tracing and region analysis is as follows: Calculate the total received energy and stray light energy within the detection area corresponding to each channel. The total received energy includes the imaging energy of this channel, the stray light energy of this channel, and the crosstalk energy of other channels. Calculate the stray light coefficient of each channel based on the total received energy and stray light energy. At the same time, perform ray path tracing on each stray light propagation path and statistically analyze the energy contribution ratio of different propagation paths.

6. The method for analyzing and optimizing the crosstalk of a multi-channel integrated filter channel according to claim 1, characterized in that, The methods for optimizing the filter channel layout include, but are not limited to, adjusting the spatial position of the channels, optimizing the channel adjacency relationship, increasing the isolation distance of high crosstalk channels, or adding light-blocking structures.

7. The method for analyzing and optimizing the crosstalk of a multi-channel integrated filter channel according to claim 1, characterized in that, The optimization of the filter channel layout is carried out through manual analysis, or through automatic layout optimization using genetic algorithms, particle swarm optimization algorithms, simulated annealing algorithms, graph theory optimization algorithms, or artificial intelligence algorithms.

8. A multi-channel integrated filter channel crosstalk analysis and layout optimization system, characterized in that, include: The model building unit is used to establish a system-level ray tracing model, which uses non-sequential ray tracing as the underlying ray propagation solution mechanism. The channel crosstalk analysis unit is used to obtain the stray light coefficient and the energy contribution ratio of the stray light propagation path within the corresponding detection area of ​​each channel based on the system-level ray tracing model through non-sequential ray tracing and region analysis. The layout optimization unit is used to optimize the filter channel layout based on the stray light coefficient and the energy contribution ratio of the stray light propagation path in the detection area corresponding to each channel. The optimization verification unit is used to re-perform non-sequential ray tracing on the optimized layout to verify the optimization effect. If the design target is met, the final layout is output; otherwise, it returns to the previous step to continue iterative optimization.

9. The multi-channel integrated filter channel crosstalk analysis and layout optimization system according to claim 8, characterized in that, In the model building unit, establishing a system-level ray tracing model specifically involves: setting the geometric structure and spatial pose of the light source, front-end optical system, multi-channel integrated filter, detector, and detector window to form a system physical model; based on the system physical model, setting the characteristics of the light source and the material properties and surface optical characteristics parameters of each optical element, and using non-sequential ray tracing as the underlying ray propagation solution mechanism to construct a system-level ray tracing model.

10. The multi-channel integrated filter channel crosstalk analysis and layout optimization system according to claim 8, characterized in that, In the channel crosstalk analysis unit, the specific method for obtaining the stray light coefficient and stray light propagation path energy contribution ratio within the corresponding detection area of ​​each channel through non-sequential ray tracing and region analysis is as follows: Calculate the total received energy and stray light energy within the detection area corresponding to each channel. The total received energy includes the imaging energy of this channel, the stray light energy of this channel, and the crosstalk energy of other channels. Calculate the stray light coefficient of each channel based on the total received energy and stray light energy. At the same time, perform ray path tracing on each stray light propagation path and statistically analyze the energy contribution ratio of different propagation paths.

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