Design method of optical system and surface feature analysis system

Abstract

The invention discloses a design method of an optical system, and the method comprises the steps: obtaining first recognition information and first feature information, the first recognition information is obtained through the feature recognition of a tested object by the optical system, and the first feature information represents the actual feature of the same tested object; determining a loss value based on the first identification information and the first feature information; updating the design of the processor based on the loss value, or updating the design of the optical component based on the loss value and the relation function, or updating the design of the optical component and the design of the processor based on the loss value and the relation function until the loss value meets a preset numerical value condition, and obtaining design information of the optical system; the relation function represents the relation between the output of the optical component and the design information of the optical component. According to the design method provided by the invention, the recognition accuracy of the optical system can be ensured, and the designed optical system can obtain a multi-dimensional feature recognition result.

Description

Technical Field

[0001] This application relates to the field of optical imaging technology, and particularly to a design method for an optical system and a surface feature analysis system. Background Art

[0002] In scenarios where an optical system is used for object recognition, especially for object surface feature recognition, the prior art usually adopts solutions such as infrared spectroscopy, scanning electron microscopy, laser scanning confocal microscopy, etc. However, the information dimension of the material properties obtained by such prior art is limited, and the equipment is expensive and the operation is complex.

[0003] The prior art also provides an optical system for realizing object imaging. However, when applied to the feature recognition scenario, it is difficult for the prior art to establish the relationship between the specific design of the optical system and the recognition accuracy. As a result, even if the designed optical system has the ability of multi-dimensional feature recognition, it cannot achieve accurate recognition. Therefore, there is an urgent need to provide a design method for an optical system and a surface feature analysis system. Summary of the Invention

[0004] One of the purposes of this application is to provide a design method for an optical system to solve the technical problems in the prior art that the optical system for feature recognition cannot achieve multi-dimensional information recognition, has limited recognition accuracy, and is costly and complex to operate.

[0005] One of the purposes of this application is to provide a surface feature analysis system.

[0006] To achieve one of the above application purposes, an embodiment of this application provides a design method for an optical system. The optical system includes: an optical component for receiving incident light from a measured object and generating a polarized light signal; a light sensor disposed on the light output side of the optical component, the light sensor being used to receive the polarized light signal and generate polarization detection information; a processor for generating recognition information according to the polarization detection information. The design method includes: obtaining first recognition information and first feature information, the first recognition information being obtained by the optical system for feature recognition of the measured object, and the first feature information representing the actual features of the same measured object; determining a loss value based on the first recognition information and the first feature information; updating the design of the processor based on the loss value, or updating the design of the optical component based on the loss value and a relationship function, or updating both the design of the optical component and the design of the processor based on the loss value and the relationship function until the loss value satisfies a preset numerical condition to obtain the design information of the optical system; the relationship function characterizing the relationship between the output of the optical component and the design information of the optical component.

[0007] Optionally, the relationship function is a point spread function.

[0008] Optionally, the optical component includes a modulation element configured to generate a polarized light signal, and the modulation element includes a microstructure unit disposed at least at one of an incident light side or an emergent light side of the modulation element.

[0009] Optionally, the design method includes at least one of the following: the optical component includes a lens, and the relationship function characterizes the relationship between the output of the optical component and the focal length of the lens; the optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the shape of the microstructure unit in the modulation element; the optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the size of the microstructure unit in the modulation element; the optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the material of the microstructure unit in the modulation element; the optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the arrangement of the microstructure units in the modulation element; the optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and a first distance, where the first distance is the distance between the modulation element and the optical sensor.

[0010] Optionally, the modulation element is configured to generate a first polarized light signal in a first region of the optical sensor and generate a second polarized light signal in a second region of the optical sensor; the design method includes at least one of the following: updating the design of the microstructure unit corresponding to the first region in the modulation element based on a loss value and a first relationship function, where the first relationship function characterizes the relationship between the output of the optical component and the design information of the microstructure corresponding to the first region; updating the design of the microstructure unit corresponding to the second region in the modulation element based on a loss value and a second relationship function, where the second relationship function characterizes the relationship between the output of the optical component and the design information of the microstructure corresponding to the second region.

[0011] Optionally, the modulation element includes a first modulation region and a second modulation region. The first modulation region includes microstructure units configured with first design information, and the second modulation region includes microstructure units configured with second design information. The first modulation region is used to generate a first polarized light signal and a third polarized light signal in the first region and the third region of the optical sensor respectively. The second modulation region is used to generate a second polarized light signal and a fourth polarized light signal in the second region and the fourth region of the optical sensor respectively. The design method includes at least one of the following: updating the first design information, updating the position of the first modulation region, or updating both the first design information and the position of the first modulation region based on a loss value and a first relationship function, where the first relationship function characterizes the relationship between the output of the optical component and the design information of the corresponding first modulation region, the position of the first modulation region, and the first polarized light signal; updating the second design information, updating the position of the second modulation region, or updating both the second design information and the position of the second modulation region based on a loss value and a second relationship function, where the second relationship function characterizes the relationship between the output of the optical component and the design information of the corresponding second modulation region, the position of the second modulation region, and the second polarized light signal; updating the first design information, updating the position of the first modulation region, or updating both the first design information and the position of the first modulation region based on a loss value and a third relationship function, where the third relationship function characterizes the relationship between the output of the optical component and the design information of the corresponding first modulation region, the position of the first modulation region, and the third polarized light signal; updating the second design information, updating the position of the second modulation region, or updating both the second design information and the position of the second modulation region based on a loss value and a fourth relationship function, where the fourth relationship function characterizes the relationship between the output of the optical component and the design information of the corresponding second modulation region, the position of the second modulation region, and the fourth polarized light signal.

[0012] Optionally, the design method includes at least one of the following: the first modulation region of the modulation element is used to generate a first polarized light signal with transverse electric mode polarization, the optical sensor is used to generate first polarization detection information conforming to the transverse electric mode polarization, and the first polarization detection information is used to generate first identification information; the second modulation region of the modulation element is used to generate a second polarized light signal with transverse electric mode polarization, the optical sensor is used to generate second polarization detection information conforming to the transverse electric mode polarization, and the second polarization detection information is used to generate first identification information; the first modulation region of the modulation element is used to generate a third polarized light signal with transverse magnetic mode polarization, the optical sensor is used to generate third polarization detection information conforming to the transverse magnetic mode polarization, and the third polarization detection information is used to generate first identification information; the second modulation region of the modulation element is used to generate a fourth polarized light signal with transverse magnetic mode polarization, the optical sensor is used to generate fourth polarization detection information conforming to the transverse magnetic mode polarization, and the fourth polarization detection information is used to generate first identification information.

[0013] Optionally, the first polarized light signal is perpendicular to the incident light, and the second polarized light signal is perpendicular to the incident light.

[0014] Optionally, the optical sensor generates n polarization detection information corresponding to n polarized light signals respectively, and the processor generates recognition information based on the operation of the preset weight parameters according to the n polarization detection information.

[0015] Optionally, the design method includes at least one of the following: the loss value is cross-entropy loss or mean square error; the optical component includes a modulation element, the modulation element includes at least two modulation regions, and at least two modulation regions have different weights when the design is updated based on the loss value; the optical sensor includes at least two regions for generating at least two polarization detection signals, and at least two polarization detection signals have different weights when the design of the processor is updated based on the loss value.

[0016] To achieve one of the above application purposes, an embodiment of the present application provides a surface feature analysis system, including: an optical component for receiving incident light from a measured object and generating a polarized light signal, an optical sensor disposed on the light output side of the optical component, the optical sensor for receiving the polarized light signal and generating polarization detection information, and a processor for generating recognition information according to the polarization detection information; the surface feature analysis system includes one of the following: the design information of the processor is determined based on a loss value, the loss value is determined based on the recognition information and preset feature information, and the feature information represents the actual features of the corresponding measured object; the design information of the optical component is determined based on a loss value and a relationship function, the loss value is determined based on the recognition information and preset feature information, the feature information represents the actual features of the corresponding measured object, and the relationship function characterizes the relationship between the output of the optical component and the design information of the optical component; the design information of the surface feature analysis system is determined based on a loss value and a relationship function, the loss value is determined based on the recognition information and preset feature information, the feature information represents the actual features of the measured object corresponding to the feature information, and the relationship function characterizes the relationship between the output of the optical component and the design information of the optical component.

[0017] Compared with the prior art, the design method of the optical system provided by the present application generates polarization detection information through an optical component and an optical sensor, and the processor can obtain a multi-dimensional feature recognition result based on the polarization detection information; by comparing the recognition information determined by the optical system with the known feature information to determine the loss value, and combining the loss value to update the design of the processor or the optical component, the optical system can be trained end-to-end to ensure the recognition accuracy of the optical system; when the design of the optical component is updated, the relationship between the design of the optical component and its output can be constructed through the relationship function to realize the end-to-end training of the optical component itself to achieve accurate recognition. Description of the Drawings

[0018] Figure 1 It is a schematic structural diagram of an optical system in an embodiment of the present application.

[0019] Figure 2 It is a schematic structural diagram of an optical sensor in an embodiment of the present application.

[0020] Figure 3 It is a schematic diagram of the cooperation between a modulation element and an optical sensor in an embodiment of the present application.

[0021] Figure 4 It is a schematic diagram of the steps of a design method of an optical system in an embodiment of the present application. Detailed Embodiments

[0022] The present application will be described in detail below in conjunction with the specific embodiments shown in the drawings. However, these embodiments do not limit the present application, and any structural, method, or functional transformation made by those of ordinary skill in the art based on these embodiments is included within the protection scope of the present application.

[0023] It should be noted that the term "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or device including a series of elements includes not only those elements but also other elements not expressly listed, or also elements inherent to such process, method, article, or device.

[0024] In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. There is no necessary correlation between the terms "first", "second", "third", etc.; for example, an embodiment provided in the present application includes "second", which does not mean that "first" must be included in this embodiment, and so on.

[0025] Optical System An embodiment of the present application provides an optical system 100, as Figure 1 shown.

[0026] The optical system 100 may be included in the surface feature analysis system described later, or the optical system 100 may be the surface feature analysis system.

[0027] The optical system 100 may be a system for processing optical signals; the optical system may be a system including optical components; the optical components include, but are not limited to, lenses, optical sensors, gratings, coolers, filters, beam splitters.

[0028] The optical system 100 includes an optical component 11.

[0029] The optical component 11 is configured to receive incident light from a subject under test. The optical component 11 is configured to generate a polarized light signal.

[0030] The optical component 11 may include one or more optical components; the optical component 11 may include one or more types of optical components, and each type of optical component may be provided with one or more.

[0031] The optical system 100 includes a light sensor 12.

[0032] The light sensor 12 is disposed on the light output side of the optical component 11. The incident light is input into the optical component 11 from the light input side of the optical component 11, and the polarized light signal generated by the optical component 11 is emitted from the light output side of the optical component 11 and output to the light sensor 12.

[0033] The light sensor 12 is configured to receive the polarized light signal. When the optical component 11 is configured to generate other light signals, based on the light sensor 12 being located on the light output side of the optical component 11, the light sensor 12 can also be configured to receive the other light signals.

[0034] The light sensor 12 is configured to generate polarization detection information. The light sensor 12 can generate a variety of polarization detection information, and different polarization detection information corresponds to different polarization states.

[0035] The light sensor 12 may include multiple regions, each region being respectively configured to detect a light signal of one polarization state and generate corresponding polarization detection information. In one embodiment, the light sensor 12 may include four regions, which are respectively configured to receive four polarized light signals.

[0036] The different polarized light signals may have different polarization modes, for example, may include a fully polarized light signal and a partially polarized light signal. The polarized light signal can be specifically distinguished according to the trajectory and vibration mode of the electric field vector, for example, may include a linearly polarized light signal, a circularly polarized light signal or an elliptically polarized light signal. The different polarized light signals may also have the same or different electromagnetic wave propagation modes, for example, may be a transverse electric mode or a transverse magnetic mode.

[0037] The optical component 11 and the light sensor 12 can be used to form an all-optical neural network. Using the all-optical neural network, polarization detection information representing the interaction between light and matter can be obtained. Specifically, based on the change in the polarization state, information about the composition of the material, the surface roughness, etc. can be obtained, thereby improving the recognition accuracy and recognition efficiency.

[0038] In some embodiments, the optical component 11 and the light sensor 12 can also be combined to form an optical module.

[0039] The optical system 100 includes a processor 13.

[0040] The processor 13 is configured to generate identification information based on polarization detection information.

[0041] The polarization detection information may include multiple groups corresponding to different polarization states. The processor 13 may generate unified identification information based on the multiple groups of polarization detection information. In this way, the optical system 100 can achieve multi-dimensional identification.

[0042] When generating the identification information, the processor 13 may construct a neural network. Specifically, the neural network may be a Convolutional Neural Network (CNN). In this application, adjusting the design information of the processor 13 may specifically be to adjust model parameters such as the weights of the neural network.

[0043] In one embodiment, the optical component 11 and the optical sensor 12 are configured to construct an all-optical neural network, and the processor 13 is configured to construct an electrical neural network. The two cooperate with each other to achieve the identification of information such as the surface microstructure, material composition, surface roughness, three-dimensional shape, contour, temperature, and pressure of the object under test, and also have the effect of improving data processing capabilities and system performance.

[0044] Optical component In one embodiment, the optical component 11 may include a lens 110.

[0045] The lens 110 may be configured to transform the incident light information from the object under test into the Fourier space to obtain the spatial frequency spectrum corresponding to the optical information of the incident light.

[0046] The incident light from the object under test may include the reflected light of the object under test. The optical information of the incident light may include signals related to the surface physical characteristics and optical response of the object under test; among the optical information of the incident light, the characteristics of polarization, intensity, spectrum, spatial distribution, and coherence may serve as the information basis for comprehensively characterizing the characteristics of the object under test.

[0047] The optical component 11 may include one or more lenses 110. When the optical component 11 includes multiple lenses 110, the multiple lenses 110 may have the same or different parameters.

[0048] In one embodiment, the optical component 11 may include a modulation element 111.

[0049] The modulation element 111 is configured to generate a polarized light signal. Specifically, the modulation element 111 modulates the spatial frequency spectrum of the optical signal to generate a polarized light signal.

[0050] The modulation element 111 may include a microstructure unit disposed on the light incident side of the modulation element 111; the modulation element 111 may include a microstructure unit disposed on the light exiting side of the modulation element 111; microstructure units may be disposed on both the light incident side and the light exiting side of the modulation element 111. In other words, the modulation element 111 includes a microstructure unit disposed at least at one of the light incident side or the light exiting side of the modulation element 111.

[0051] The modulation element 111 may be configured as a metasurface optical element.

[0052] Among them, a metasurface refers to an artificial layered material with a size smaller than or approximately equal to the wavelength, which can be regarded as the two-dimensional counterpart of metamaterials. A metasurface optical element can achieve the regulation of characteristics such as polarization, phase, amplitude, frequency, and propagation mode of electromagnetic waves through sub-wavelength microstructure units (also known as superstructure units) on the surface, and achieve characteristics such as beam shaping, beam deflection, superlens, super holography, optical rotation, and anti-reflection and anti-reflection enhancement.

[0053] The metasurface optical element can be a sub-wavelength size optical element, which is suitable for the current micron-scale sensor architecture. At the same time, its manufacturing process is compatible with mature semiconductor sensor technologies, and it has strong practicability and economy.

[0054] Specifically, the metasurface optical element includes a substrate and a plurality of microstructure units arranged in an array on the substrate. Nanostructures are provided at the center and / or vertex positions of each microstructure unit. The microstructure unit is obtained by dividing the metasurface optical element into a structural unit centered on each nanostructure. Among them, the nanostructures in each period form a microstructure unit. The microstructure unit is a densely packable pattern, such as a regular quadrilateral, a regular hexagon, a sector, etc. Each period contains one nanostructure, and nanostructures can be provided at the vertices and / or centers of the microstructure unit. In the case where the microstructure unit is a regular hexagon, at least one nanostructure is provided at each vertex and center position of the regular hexagon. Similarly, the same is true in the case of a sector or a square.

[0055] Among them, the substrate of the metasurface optical element can be selected, for example: glass materials with similar refractive indexes such as silicon dioxide, BF33, etc., silicon, polymethyl methacrylate, etc.; the nanostructures can be selected, for example: monocrystalline silicon (c-Si), polycrystalline silicon (p-Si), amorphous silicon (a-Si), compound semiconductors (such as GaN, GaP, GaAs, SiC, etc.), TiO2, Si3N4, AlSb, AlAs, AlGaAs, AlGaInP, BP, ZnGeP2 and other suitable materials and combinations of the above materials.

[0056] Specifically, the nanostructure can be configured as a polarization-dependent structure or a polarization-independent structure. According to different usage scenarios, the microstructure unit can be selectively configured as a polarization-dependent structure or a polarization-independent structure. Polarization-independent structures include, for example, cylindrical, square-columnar, cross-columnar, circular-hole square-columnar, etc. Polarization-dependent structures include, for example, elliptical-cylindrical, rectangular-columnar, hexagonal-columnar, etc. The nanostructure can be a positive structure or a negative structure. For example, the shapes of the nanostructure include cylinder, hollow cylinder, square prism, hollow square prism, etc.

[0057] The metasurface optical element may further include a protective layer covering the nanostructure. The material of the protective layer can be any material with a low refractive index and absorption coefficient in the visible or near-infrared band, such as: silicon dioxide (SiO2), spin-on glass (SOG), or polymers such as polymethyl methacrylate (PMMA), polydimethylsiloxane (PDMS), polymethylpentene (PMP), and combinations of the above materials. It can also be air (i.e., without setting a protective layer).

[0058] The optical component 11 may include one or more modulation elements 111. When the optical component 11 includes multiple modulation elements 111, the multiple modulation elements 111 can have the same or different parameters, and the multiple modulation elements 111 can be arranged at intervals in the propagation direction of the incident light.

[0059] In one embodiment, the optical system 100 includes at least one lens 110, at least one modulation element 111, and a light sensor 12. In a specific embodiment, the optical system includes one lens 110, one modulation element 111, and one light sensor 12. In a specific embodiment, the optical system includes multiple lenses 110, one modulation element 111, and one light sensor 12. In a specific embodiment, the optical system includes one lens 110, multiple modulation elements 111, and one light sensor 12. In a specific embodiment, the optical system includes multiple lenses 110, multiple modulation elements 111, and one light sensor 12.

[0060] In a preferred embodiment of the present application, starting from the object under test, the optical system 100 is sequentially provided with a lens 110, a modulation element 111, and a light sensor 12. In this embodiment, the modulation element 111 is disposed on the light-emitting side of the lens 110, and specifically can be disposed on the rear focal plane of the lens 110. In other embodiments, it can also be arranged in the order of modulation element 111, lens 110, and light sensor 12, or multiple lenses 110 and multiple modulation elements 111 can be alternately arranged in front of the light sensor 12.

[0061] In some embodiments, the modulation element 111 and the optical sensor 12 can be separately disposed independently, or can be integrally disposed. When integrally disposed, the modulation element 111 and the optical sensor 12 can be combined by means such as thermal bonding, plasma bonding, adhesive bonding, etc.; or, a metasurface can be directly fabricated on the optical sensor 12. For example: First, an optical film layer is formed on the light-receiving surface of the semiconductor substrate, and then, the optical film layer is etched into a metasurface through a photolithography process.

[0062] In some embodiments, when the modulation element 111 and the optical sensor 12 are separately and independently disposed, the optical system 100 may further include a dielectric layer located between the modulation element 111 and the optical sensor 12. The material of the dielectric layer can be any material having a low refractive index and absorption coefficient in the visible or near-infrared band. For example: silicon dioxide (SiO2), spin-on glass (SOG), or polymers such as polymethyl methacrylate (PMMA), polydimethylsiloxane (PDMS), polymethylpentene (PMP), etc., and combinations of the above materials.

[0063] In some embodiments, the optical assembly 11 or the optical system 100 may further include an illumination element for emitting laser light, and the illumination element may specifically be a light-emitting diode (LED). In this way, the optical system can better analyze the polarization detection information of the reflected light of the object under test.

[0064] In some embodiments, the optical assembly 11 or the optical system 100 may further include at least one refractive optical element, at least one diffractive optical element, and / or at least one scattering medium element. Among them, the refractive optical element includes, but is not limited to, lenses or prisms made of materials such as optical glass, optical plastics, optical crystals, etc.; the diffractive optical element includes, but is not limited to, two-step or multi-step diffractive optical elements, gratings, Dammann gratings, metasurfaces, holograms, diffusers, phase masks, intensity masks, spatial light modulators, etc., and the scattering medium element includes, but is not limited to, frosted glass, etc.

[0065] Optical sensor The optical sensor 12 may specifically be a CMOS (Complementary Metal Oxide Semiconductor) photosensitive element (CIS, CMOS Image Sensor), a CCD (Charge Coupled Device) photosensitive element, or an array light detector.

[0066] Such as Figure 2As shown, the optical sensor 12 may include multiple regions. In one embodiment, the optical sensor 12 may include a first region Z21, a second region Z22, a third region Z23, and a fourth region Z24. In other embodiments, the optical sensor 12 may include a greater or fewer number of regions.

[0067] The regions in the optical sensor 12 may be only conceptually divided and have no essential difference in physical structure.

[0068] The different regions in the optical sensor 12 are used to receive different polarized light signals. The information about the object under test carried in the different polarized light signals complements each other, and the different polarized light signals can be regarded as different polarization components.

[0069] In one embodiment, the four regions correspond to four polarized light signals, and the four polarized light signals are generated based on the modulation of the optical component 11. For the modulation process corresponding to each polarized light signal, in theory, it can be characterized by a relationship function. The four polarized light signals correspond to the four regions and also correspond to four relationship functions.

[0070] In one embodiment, the relationship function may be a Point Spread Function (PSF).

[0071] The first region Z21 corresponds to the first relationship function PSF1, the second region Z22 corresponds to the second relationship function PSF2, the third region Z23 corresponds to the third relationship function PSF3, and the fourth region Z24 corresponds to the fourth relationship function PSF4.

[0072] The first region Z21 is used to generate first polarization detection information, and the first polarization detection information may satisfy: First polarization detection information = incident light signal of the object under test * first relationship function PSF1.

[0073] The second region Z22 is used to generate second polarization detection information, and the second polarization detection information may satisfy: Second polarization detection information = incident light signal of the object under test * second relationship function PSF2.

[0074] The third region Z23 is used to generate third polarization detection information, and the third polarization detection information may satisfy: Third polarization detection information = incident light signal of the object under test * third relationship function PSF3.

[0075] The fourth region Z24 is used to generate fourth polarization detection information, and the fourth polarization detection information may satisfy: Fourth polarization detection information = incident light signal of the object under test * fourth relationship function PSF4.

[0076] For the processor 13, the processor 13 generates recognition information corresponding to four polarization detection information. The processor 13 can perform operations on the polarization detection information according to preset weights to determine the recognition information. The preset weights can be set and adjusted according to the relevance between the polarized light signal and the feature recognition task. For example, if the type of the polarized light signal corresponding to the first region Z21 has a stronger relevance to the current task, the first polarization detection information is selected to generate the recognition information, or a higher weight is set for the first polarization detection information.

[0077] Specifically, the processor 13 has a first weight w1 for the first polarized light signal or the first region Z21, a second weight w2 for the second polarized light signal or the second region Z22, a third weight w3 for the third polarized light signal or the third region Z23, and a fourth weight w4 for the fourth polarized light signal or the fourth region Z24.

[0078] The recognition information can satisfy: recognition information = w1 × first polarization detection information + w2 × second polarization detection information + w3 × third polarization detection information + w4 × fourth polarization detection information.

[0079] For the optical component 11, in order to generate different polarized light signals for different regions on the optical sensor 12, the optical component 11 can also include one or more regions for generating the different optical signals.

[0080] As Figure 3 shown, the optical component 11 can include a modulation element 111, and the modulation element 111 can include a first modulation region Z11 and a second modulation region Z12.

[0081] The optical component 11 can include one modulation element 111, and the first modulation region Z11 and the second modulation region Z12 can be two regions on the modulation element 111; specifically, the two modulation regions can be two regions on the metasurface of the modulation element 111.

[0082] The optical component 11 can include at least two modulation elements 111. The first modulation region Z11 can be formed in one of the modulation elements, and the second modulation region Z12 can be formed in another of the modulation elements. The two modulation elements can be arranged on the same plane.

[0083] The two modulation regions can have the same design or different designs. The two modulation regions can each include microstructure units. In one embodiment, the first modulation region Z11 can include microstructure units configured with first design information, and the second modulation region Z12 can include microstructure units configured with second design information. In this way, the first modulation region Z11 and the second modulation region Z12 can generate different polarized light signals.

[0084] In one embodiment, the modulation element 111 is configured to generate a first polarized light signal in the first region Z21 of the optical sensor 12; the modulation element 111 is configured to generate a second polarized light signal in the second region Z22 of the optical sensor 12. Specifically, for example, the first modulation region Z11 generates a first polarized light signal in the first region Z21, and the second modulation region Z12 generates a second polarized light signal in the second region Z22.

[0085] The first polarized light signal and the second polarized light signal differ at least based on differences in the design information of the first polarization region Z11 and the second polarization region Z12.

[0086] In one embodiment, the first modulation region Z11 is configured to generate a first polarized light signal and a third polarized light signal in the optical sensor 12; specifically, for example, the first modulation region Z11 generates a first polarized light signal in the first region Z21 and a third polarized light signal in the third region Z23. The second modulation region Z12 is configured to generate a second polarized light signal and a fourth polarized light signal in the optical sensor 12; specifically, for example, the second modulation region Z12 generates a second polarized light signal in the second region Z22 and a fourth polarized light signal in the fourth region Z24.

[0087] The first polarized light signal and the third polarized light signal may differ based on different electromagnetic wave propagation modes; the second polarized light signal and the fourth polarized light signal may differ based on different electromagnetic wave propagation modes. The electromagnetic wave propagation modes may include transverse magnetic mode and transverse electric mode.

[0088] The first polarized light signal is perpendicular to the light propagation direction; the first polarized light signal is perpendicular to the incident light. The second polarized light signal is perpendicular to the light propagation direction; the second polarized light signal is perpendicular to the incident light. The third polarized light signal is perpendicular to the light propagation direction; the third polarized light signal is perpendicular to the incident light. The fourth polarized light signal is perpendicular to the light propagation direction; the fourth polarized light signal is perpendicular to the incident light. Specifically, the polarization direction of the above-mentioned polarized light signals is perpendicular to the propagation direction of the incident light.

[0089] In one embodiment, the relationship function is related to the design of the microstructure units in the modulation element 111.

[0090] The first relationship function PSF1 is related to the design information of the microstructure units in the first modulation region Z11. The third relationship function PSF3 is related to the design information of the microstructure units in the first modulation region Z11. The design information of the microstructure units in the first modulation region Z11 is , then the first relationship function PSF1 satisfies: , the third relationship function PSF3 satisfies: .

[0091] The second relationship function PSF2 is related to the design information of the microstructure units in the second modulation region Z12. The fourth relationship function PSF4 is related to the design information of the microstructure units in the second modulation region Z12. The design information of the microstructure units in the second modulation region Z12 is , then the second relationship function PSF2 satisfies: , and the fourth relationship function PSF4 satisfies: .

[0092] Among them, the design information of the microstructure units includes at least one of the following: shape, size, material, arrangement (for example, rotation angle, arrangement period).

[0093] In one embodiment, the relationship function is related to the focal length of the lens 110.

[0094] In one embodiment, the relationship function is related to the distance between the modulation element 111 and the optical sensor 12.

[0095] The focal length of the lens 110 and the distance between the modulation element 111 and the optical sensor 12 can be summarized as the optical hyperparameter d of the optical system 100. The first relationship function PSF1 satisfies: , the second relationship function PSF2 satisfies: , the third relationship function PSF3 satisfies: , and the fourth relationship function PSF4 satisfies: .

[0096] In addition, when the modulation element 111 is disposed at the rear focal plane of the lens 110, the optical hyperparameter d can also be regarded as the setting position of the modulation element 111. At this time, the optical hyperparameter d is specifically used to characterize the distance between the lens 110 and the modulation element 111, and the distance between the modulation element 111 and the optical sensor 12.

[0097] When the first modulation region Z11 and the second modulation region Z12 are disposed at different modulation elements, the first modulation region Z11 and the second modulation region Z12 may have different optical hyperparameters based on having different distances from the lens 110 or the optical sensor 12. In this embodiment, the first relationship function PSF1 and the third relationship function PSF3 are related to the optical hyperparameters of the first modulation region Z11, and the second relationship function PSF2 and the fourth relationship function PSF4 are related to the optical hyperparameters of the second modulation region Z12.

[0098] In one embodiment, the relationship function is related to the propagation mode of the polarized light signal.

[0099] The propagation modes of the polarized light signal may include the transverse electric mode and the transverse magnetic mode.

[0100] The differences in the propagation modes can be different based on the differences in the incident optical signal itself, or based on the processing of the lens 110, or based on the modulation of the modulation element 111.

[0101] Specifically, the modulation element 111 can be used to modulate the incident light to form a polarized light signal of one propagation mode at a region of the rear component and a polarized light signal of another propagation mode at another region of the rear component after the modulation of the propagation mode; or, form a polarized light signal of one propagation mode at one rear component and a polarized light signal of another propagation mode at another rear component.

[0102] The first modulation region Z11 is used to generate a first polarized light signal with a transverse electric mode polarization , and the first relationship function PSF1 satisfies: . The first modulation region Z11 is used to generate a third polarized light signal with a transverse magnetic mode polarization , and the third relationship function PSF3 satisfies: .

[0103] The second modulation region Z12 is used to generate a second polarized light signal with a transverse electric mode polarization , and the second relationship function PSF2 satisfies: . The second modulation region Z12 is used to generate a fourth polarized light signal with a transverse magnetic mode polarization , and the fourth relationship function PSF4 satisfies: .

[0104] In a preferred embodiment, the first relationship function PSF1 satisfies: .

[0105] In a preferred embodiment, the second relationship function PSF2 satisfies: .

[0106] In a preferred embodiment, the third relationship function PSF3 satisfies: .

[0107] In a preferred embodiment, the fourth relationship function PSF4 satisfies: .

[0108] Surface feature analysis system One embodiment of the present application provides a surface feature analysis system.

[0109] In one embodiment, the surface feature analysis system may include the aforementioned optical system 100.

[0110] In one embodiment, the surface feature analysis system may include an optical component 11. The optical component 11 may be configured as in any of the foregoing embodiments. For example, the optical component 11 is used to receive incident light from a subject to be measured and generate a polarized light signal.

[0111] In one embodiment, the surface feature analysis system may include a light sensor 12. The light sensor 12 may be configured as in any of the foregoing embodiments. For example, the light sensor 12 is disposed on the light output side of the optical component 11; the light sensor 12 is used to receive the polarized light signal and generate polarization detection information.

[0112] In one embodiment, the surface feature analysis system may include a processor 13. The processor 13 may be configured as in any of the foregoing embodiments. For example, the processor 13 is used to generate identification information based on the polarization detection information.

[0113] In one embodiment, the processor 13 may be specifically configured as follows: the design information of the processor 13 is determined based on a loss value, the loss value is determined based on the identification information and preset feature information, and the preset feature information represents the actual features of the corresponding subject to be measured.

[0114] In one embodiment, the optical component 11 may be specifically configured as follows: the design information of the optical component 11 is determined based on a loss value and a relationship function, the loss value is determined based on the identification information and preset feature information, the feature information represents the actual features of the corresponding subject to be measured, and the relationship function characterizes the relationship between the output of the optical component 11 and the design information of the optical component 11.

[0115] In one embodiment, the surface feature analysis system may be specifically configured as follows: the design information of the surface feature analysis system is determined based on a loss value and a relationship function, the loss value is determined based on the identification information and preset feature information, the feature information represents the actual features of the corresponding subject to be measured, and the relationship function characterizes the relationship between the output of the optical component 11 and the design information of the optical component 11.

[0116] In different application scenarios, the subjects to be measured corresponding to the surface feature analysis system are different.

[0117] In one embodiment, when the surface feature analysis system is applied to the remote sensing and environmental monitoring scenario, the subjects to be measured may be aerosols and particulate matters in the atmosphere, suspended particles, algae and other substances in water bodies, etc.

[0118] In one embodiment, when the surface feature analysis system is applied to the medical imaging and diagnosis scenario, the subjects to be measured may be biological tissues or cells.

[0119] In one embodiment, the surface feature analysis system is applied to an autonomous driving scenario, and the object to be measured can be the detection target of a lidar (LiDAR) system in an autonomous vehicle.

[0120] In one embodiment, the surface feature analysis system is applied to a semiconductor manufacturing scenario, and the object to be measured can be the wafer interface and the attached residues on the wafer surface.

[0121] In a preferred embodiment, when the surface feature analysis system works, first, the lens 110 transforms the information of the incident light into the Fourier space to obtain the spatial frequency spectrum corresponding to the incident light; then, the modulation element 111 and the optical sensor 12 cooperate to separate the spatial frequency spectrum to obtain multiple polarization detection information corresponding to multiple polarization states; finally, the processor 13 uses a neural network model to determine the recognition information of the characteristics of the object to be measured based on the multiple polarization detection information.

[0122] Design method of an optical system One embodiment of the present application provides a design method of an optical system, as Figure 4 shown.

[0123] Since the surface feature analysis system may include the optical system 100, the design method provided by the present application can also be used to design the optical system 100 in the surface feature analysis system.

[0124] Since the surface feature analysis system may be the optical system 100, the design method provided by the present application can also be used to design the surface feature analysis system.

[0125] The design method provided by the present application includes at least one of the following steps.

[0126] Step S1, obtaining first recognition information and first feature information.

[0127] Step S2, determining a loss value based on the first recognition information and the first feature information.

[0128] Step S3, updating the design of the processor based on the loss value, or updating the design of the optical component based on the loss value and the relationship function, or updating both the design of the optical component and the design of the processor based on the loss value and the relationship function, until the loss value meets the preset numerical condition to obtain the design information of the optical system.

[0129] The first recognition information is obtained by the optical system's recognition of the characteristics of the object to be measured. The first feature information represents the actual characteristics of the same object to be measured.

[0130] At this time, the optical system is in the design stage (or, the configuration stage, the training stage). The first recognition information can be understood as the test feature, and the first feature information can be understood as the actual feature. In the design stage, the actual features of the object under test are known, and the object under test can correspond to a preset recognition task. The purpose of this stage is to make the first recognition information approach the first feature information by adjusting the design of the optical system, so that the optical system can perform the preset recognition task.

[0131] The relationship function characterizes the relationship between the output of the optical component and the design information of the optical component.

[0132] This does not mean that the relationship function can only characterize the relationship between the output of the optical component and the design information of the optical component. In some embodiments of the present application, the relationship function can also characterize the relationship between the output of the optical component, the information of the incident light of the optical component, and the design information of the optical component. In some embodiments of the present application, the relationship function can also characterize the relationship between the output of the optical component, the intermediate information of the optical component (for example, the polarized light signal or the polarization detection information), and the design information of the optical component.

[0133] This kind of relationship can be characterized by the phenomenon that when one item is adjusted, the other item changes accordingly. For example, on the basis of keeping other parameters unchanged, adjusting the design information of the optical component, the output of the optical component changes accordingly.

[0134] Correspondingly, when designing the optical system, based on the relationship function, by adjusting the design information of the optical component, the purpose of making the output of the optical component approach the target can be achieved, so as to fix the design of the optical component.

[0135] The output of the optical component can be the polarized light signal it generates, the light field distribution of the image output by the optical component, or can be specifically characterized by the polarization detection information generated by the optical sensor, or specifically characterized by the recognition information generated by the processor. This is because the polarized light signal is processed by the optical sensor to generate polarization detection information, and the polarization detection information can be used to express the polarized light signal output by the optical component. Therefore, the polarization detection information can be an output of the optical component. Similarly, since the polarization detection information is further processed by the processor to generate recognition information, the recognition information can also be an output of the optical component.

[0136] The loss value is used to represent the difference between the first recognition information and the first feature information. When updating the design of the processor or the optical component based on the loss value, the goal is to reduce the loss value, that is, to reduce the difference between the first recognition information and the first feature information.

[0137] In the process of updating the design of a processor, the updated design information can be instructions, code, or hardware-related parameters such as memory allocation that the processor executes.

[0138] In one embodiment, when the processor generates identification information, it constructs a neural network model, especially a convolutional neural network model. At this time, updating the design of the processor can specifically be updating the model parameters of the neural network model. The model parameters can include at least one of the following: parameters for defining the model architecture, model weight parameters, model bias parameters, initialization parameters, hyperparameters (e.g., learning rate, optimizer, loss function, regularization parameter, batch size, number of training epochs, learning rate scheduling strategy), process parameters (e.g., gradient, momentum, second moment estimation).

[0139] In the process of updating the design of an optical component, the updated design information can be about the relationship between various optical elements within the optical component, about the metasurface within the optical component, about the characteristics of the optical elements themselves within the optical component, etc.

[0140] The relationship between various optical elements within the optical component can specifically include the combination method of the optical elements, the distance between each optical element, etc. For example, updating the distance between multiple modulation elements (or, modulation regions, metasurfaces), or updating the distance between multiple lenses, or updating the distance between a lens and a modulation element (or, modulation region, metasurface).

[0141] The metasurface within the optical component can be disposed on a modulation element in the optical component, or at a specific modulation region. The metasurface is mainly composed of microstructure units, and the microstructure units can include several nanostructures. At this time, the design information of the metasurface can specifically include at least one of the geometric structure, size, or spatial arrangement of the nanostructures for forming the metasurface. In some embodiments, the configuration of the metasurface can include at least one of the arrangement period, material, shape, and position coordinates of the nanostructures.

[0142] For different optical elements within the optical component, the characteristics of the optical elements themselves can be different.

[0143] For refractive optical elements, its design information can include at least one of material, surface curvature, thickness, surface shape, or include refractive index, radius of curvature, etc. Specifically, for spherical refractive optical elements, its design information can include at least one of material, surface curvature, and glass thickness; for aspherical refractive optical elements, in addition to the above material, surface curvature, and glass thickness, its design information can also include surface shape.

[0144] For a diffractive optical element, its design information may include at least one of the diffraction order, the period of the microstructure, the height of the microstructure, the refractive index, or may include focal length characteristics, the phase function of the diffractive surface, the radial radius at the abrupt change of each annulus of the diffractive surface, the annulus depth of the diffractive surface, and the diffraction efficiency, etc.

[0145] For a scattering medium element, its design information may include at least one of surface roughness, particle distribution uniformity, the depth of frosting or acid etching, the thickness, or may include scattering coefficient, absorption coefficient, phase function, scattering length, opacity or transmittance, anisotropy factor, optical thickness, scattering efficiency, particle size distribution, etc.

[0146] The preset numerical conditions may be that the loss value converges, or the loss value is greater than the preset value, or the loss value is less than the preset value.

[0147] The design information of the optical system determined in step S3 may include the design information of the updated processor, or the design information of the updated optical component, or both the design information of the updated processor and the design information of the updated optical component.

[0148] Step S1 may further include a step of initializing the design information of the optical system. Based on this, if a certain design information is not updated after performing the steps of the design method, the design information obtained in step S3 may include the initial design information. For example, step S1 initializes the design information of the processor and the optical component. If step S3 only updates the design information of the optical component, the design information of the optical system obtained in step S3 may include the initial design information of the processor and the updated design information of the optical component.

[0149] In one embodiment, the relationship function is a point spread function.

[0150] The point spread function may be the response function of the optical component to a point light source. The morphology of the point spread function (e.g., width, sidelobe, phase distribution) directly determines the optical transfer function of the optical component or the optical system, thereby affecting the imaging resolution, depth of field, and aberration characteristics.

[0151] The design information of the optical component changes the wavefront of the incident light by affecting the local phase. The point spread function, as a transfer function, constructs the relationship between the output of the optical component and the design information of the optical component, thereby realizing the encoding of the light field and the programming of the optical component.

[0152] In other embodiments, the relationship between the two may also be characterized by implementing a light field transfer matrix, angular spectrum propagation, Zernike polynomial decomposition, etc.

[0153] In one embodiment, the optical component includes a modulation element configured to generate a polarized light signal.

[0154] The modulation element can be configured according to any of the foregoing technical solutions. In a preferred embodiment, the modulation element is configured to generate at least two different polarized light signals, based on which the optical sensor and the processor can achieve multi-dimensional detection.

[0155] Based on this, the design information of the optical component in the design method may include the design information of the modulation element. Updating the design information of the optical component in step S3 may specifically be updating the design information related to the characteristics of the polarized light signal in the modulation element.

[0156] In one embodiment, the modulation element is configured to generate a polarized light signal with transverse magnetic mode polarization and a polarized light signal with transverse electric mode polarization. Based on this, updating the design information of the optical component in step S3 may be updating the design information related to the electromagnetic wave propagation mode in the modulation element.

[0157] In one embodiment, the design information of the optical component updated in step S3 may also be the positional relationship, spacing, or optical characteristics of optical components such as the modulation element.

[0158] In one embodiment, the modulation element includes a microstructural unit disposed at least at one of the incident light side or the emergent light side of the modulation element.

[0159] The microstructural unit can be configured according to any of the foregoing technical solutions. In a preferred embodiment, the microstructural unit includes a plurality of nanostructures. The design information of the optical component may include the design information of the modulation element, the design information of the modulation element may include the design information of the microstructural unit, and the design information of the microstructural unit may be the design information of the nanostructures.

[0160] In one embodiment, the optical component includes a lens, and the relationship function characterizes the relationship between the output of the optical component and the focal length of the lens.

[0161] The modulation element may be disposed on the rear focal plane of the lens, and the distance between the modulation element and the lens may be equal to the numerical value of the focal length of the lens. Based on this, the relationship function may also characterize the relationship between the output of the optical component and the distance between the lens and the modulation element.

[0162] When there are p modulation elements, the p modulation elements are respectively configured to set p modulation regions, and q different regions on the optical sensor corresponding to the p modulation regions form q relationship functions, where p and q are integers greater than or equal to 2. If the distances between the p modulation elements and the lens are different, the design information for characterizing the distance between the lens and the modulation element in the q relationship functions corresponding to the p modulation elements is different.

[0163] In a preferred embodiment of the present application, the modulation regions are at least arranged on the same plane, and this plane is located at the rear focal plane of the lens. Therefore, the distances from the multiple modulation regions to the lens are equal, the focal length of the lens is fixed, and the design information used to characterize the focal length of the lens in the multiple relationship functions corresponding to the multiple modulation regions is the same.

[0164] In one embodiment, the optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the first distance. The first distance is the distance between the modulation element and the photosensor.

[0165] The focal length of the lens and the first distance between the modulation element and the photosensor can be summarized as an optical hyperparameter d, and this optical hyperparameter d can be configured according to any of the foregoing technical solutions.

[0166] Based on this, the relationship function can characterize the relationship between the output of the optical component and the optical hyperparameter d. Step S3 may include the steps of: updating the optical hyperparameter d based on the loss value and the relationship function.

[0167] In one embodiment, the optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the shape of the microstructural unit in the modulation element.

[0168] The shape of the microstructural unit may include the overall shape of the microstructural unit and the shape of the nanostructures included therein.

[0169] The relationship function can characterize the relationship between the output of the optical component and the shape of the microstructural unit. Step S3 may include the steps of: updating the shape of the microstructural unit based on the loss value and the relationship function.

[0170] In one embodiment, the optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the size of the microstructural unit in the modulation element.

[0171] The size of the microstructural unit may include the overall size of the microstructural unit and the size of the nanostructures included therein. The size may be the size in any preset direction.

[0172] The relationship function can characterize the relationship between the output of the optical component and the size of the microstructural unit. Step S3 may include the steps of: updating the size of the microstructural unit based on the loss value and the relationship function.

[0173] In one embodiment, the optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the material of the microstructural unit in the modulation element.

[0174] The material of the microstructure unit may include the material of the substrate in the microstructure unit and the material of the nanostructure.

[0175] The relationship function may characterize the relationship between the output of the optical component and the material of the microstructure unit. Step S3 may include the step of updating the material of the microstructure unit based on the loss value and the relationship function.

[0176] In one embodiment, the optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the arrangement of the microstructure units in the modulation element.

[0177] The arrangement of the microstructure units may include the position and orientation (e.g., rotation angle) of the microstructure units themselves or the nanostructures therein, and may also include the positional arrangement (e.g., arrangement period) between multiple microstructure units.

[0178] The relationship function may characterize the relationship between the output of the optical component and the arrangement of the microstructure units. Step S3 may include the step of updating the arrangement of the microstructure units based on the loss value and the relationship function.

[0179] The design information such as the shape, size, material, and arrangement of the microstructure units can be summarized as the design information of the microstructure unit , and the design information of this microstructure unit can be configured according to any of the foregoing technical solutions.

[0180] Based on this, the relationship function may characterize the relationship between the output of the optical component and the design information of the microstructure unit Step S3 may include the step of updating the design information of the microstructure unit based on the loss value and the relationship function .

[0181] The design information of the microstructure unit depends on the design of the microstructure units in the modulation region. Whether the modulation region is integrated into one modulation element or separately provided in different modulation elements, once the design of the microstructure units therein is different, the corresponding design information of the microstructure unit is different, and the constructed relationship function is also different.

[0182] In one embodiment, the modulation element is used to generate a first polarized light signal in the first region of the optical sensor, and the modulation element is used to generate a second polarized light signal in the second region of the optical sensor.

[0183] The first polarized light signal is different from the second polarized light signal. The two polarized light signals may only differ in the generation area of the optical sensor, may also differ based on the difference in the generated modulation area, or may differ based on the difference in the propagation mode. The first polarized light signal and the second polarized light signal may also have at least two of the above three differences.

[0184] For example, in a preferred embodiment of the present application, in combination with Figure 3 As shown, the first polarized light signal is generated by the first modulation area Z11 and is generated at the first area Z21, and the second polarized light signal is generated by the second modulation area Z11 and is generated at the second area Z22. There are differences in the areas on the optical sensor and differences in the modulation areas between the two.

[0185] For the first polarized light signal and the fourth polarized light signal generated by the second modulation area Z12 and generated at the fourth area Z24, there may be differences in the areas on the optical sensor, differences in the modulation areas, and differences in the propagation modes between the two.

[0186] In a specific embodiment, the design method includes: updating the design of the microstructure unit corresponding to the first area in the modulation element based on the loss value and the first relationship function, and the first relationship function characterizes the relationship between the output of the optical component and the design information of the microstructure corresponding to the first area.

[0187] This step may be specifically included in step S3.

[0188] In a specific embodiment, the design method includes: updating the design of the microstructure unit corresponding to the second area in the modulation element based on the loss value and the second relationship function, and the second relationship function characterizes the relationship between the output of the optical component and the design information of the microstructure corresponding to the second area.

[0189] This step may be specifically included in step S3.

[0190] In a preferred embodiment of the present application, step S3 includes the above two steps at the same time. It is equivalent to having two relationship functions for the two polarized light signals generated on two areas of the optical sensor respectively. When updating the design of the optical component, the designs of the microstructure units related to the two polarized light signals are adjusted according to the two relationship functions respectively to achieve targeted update, which helps to quickly design.

[0191] If the two polarized light signals are respectively generated in two different modulation areas, it is equivalent to adjusting the relevant one modulation area according to one relationship function and adjusting the relevant other modulation area according to the other relationship function to prevent unnecessary adjustment of the irrelevant microstructure units.

[0192] In one embodiment, the modulation element includes a first modulation region and a second modulation region. The first modulation region includes microstructure units configured with first design information, and the second modulation region includes microstructure units configured with second design information. The first modulation region is used to generate a first polarized light signal and a third polarized light signal in a first region and a third region of the optical sensor respectively, and the second modulation region is used to generate a second polarized light signal and a fourth polarized light signal in a second region and a fourth region of the optical sensor respectively.

[0193] The first polarized light signal, the second polarized light signal, the third polarized light signal, and the fourth polarized light signal are different. In addition to the differences in the aforementioned modulation regions and the generation regions of the optical sensor, there may also be differences in the propagation modes between the first polarized light signal and the third polarized light signal, and there may also be differences in the propagation modes between the second polarized light signal and the fourth polarized light signal.

[0194] For example, as shown in Figure 3 , the first polarized light signal generated by the first modulation region Z11 and generated at the first region Z21 has a transverse electric mode polarization; the second polarized light signal generated by the second modulation region Z12 and generated at the second region Z22 has a transverse electric mode polarization; the third polarized light signal generated by the first modulation region Z11 and generated at the third region Z23 has a transverse magnetic mode polarization; the fourth polarized light signal generated by the second modulation region Z12 and generated at the fourth region Z24 has a transverse magnetic mode polarization.

[0195] In a specific embodiment, the design method includes: updating the first design information, updating the position of the first modulation region, or updating both the first design information and the position of the first modulation region based on a loss value and a first relationship function, where the first relationship function characterizes the relationship between the output of the optical component and the design information of the corresponding first modulation region, the position of the first modulation region, and the first polarized light signal.

[0196] The first design information may be the shape, size, material, arrangement, etc. of the microstructure units in the first modulation region.

[0197] The position of the first modulation region may include the distance between the first modulation region and the optical sensor, or may include the distance between the first modulation region and the lens. When the first modulation region is always disposed at the rear focal plane of the lens, updating the position of the first modulation region may specifically be adjusting the focal length of the lens.

[0198] The first relationship function may specifically characterize the propagation mode of the first polarized light signal.

[0199] In a preferred embodiment, the first relationship function PSF1 satisfies: .

[0200] In a specific embodiment, the design method includes: updating the second design information, updating the position of the second modulation region, or updating both the second design information and the position of the second modulation region based on a loss value and a second relationship function, where the second relationship function characterizes the relationship between the output of the optical component and the design information of the corresponding second modulation region, the position of the second modulation region, and the second polarized light signal.

[0201] The second design information may be the shape, size, material, arrangement, etc. of the microstructure units in the second modulation region.

[0202] The position of the second modulation region may include the distance between the second modulation region and the optical sensor, or may include the distance between the second modulation region and the lens. When the second modulation region is always set on the rear focal plane of the lens, updating the position of the second modulation region may specifically be adjusting the focal length of the lens.

[0203] The second relationship function may specifically characterize the propagation mode of the second polarized light signal.

[0204] In a preferred embodiment, the second relationship function PSF2 satisfies: .

[0205] In a specific embodiment, the design method includes: updating the first design information, updating the position of the first modulation region, or updating both the first design information and the position of the first modulation region based on a loss value and a third relationship function, where the third relationship function characterizes the relationship between the output of the optical component and the design information of the corresponding first modulation region, the position of the first modulation region, and the third polarized light signal.

[0206] The third relationship function may specifically characterize the propagation mode of the third polarized light signal.

[0207] In a preferred embodiment, the third relationship function PSF3 satisfies: .

[0208] In a specific embodiment, the design method includes: updating the second design information, updating the position of the second modulation region, or updating both the second design information and the position of the second modulation region based on a loss value and a fourth relationship function, where the fourth relationship function characterizes the relationship between the output of the optical component and the design information of the corresponding second modulation region, the position of the second modulation region, and the fourth polarized light signal.

[0209] The fourth relationship function may specifically characterize the propagation mode of the fourth polarized light signal.

[0210] In a preferred embodiment, the fourth relationship function PSF4 satisfies: .

[0211] In one embodiment, the first modulation region of the modulation element is used to generate a first polarization optical signal with transverse electric mode polarization. The optical sensor is used to generate first polarization detection information conforming to the transverse electric mode polarization, and the first polarization detection information is used to generate first identification information.

[0212] In one embodiment, the second modulation region of the modulation element is used to generate a second polarization optical signal with transverse electric mode polarization. The optical sensor is used to generate second polarization detection information conforming to the transverse electric mode polarization, and the second polarization detection information is used to generate first identification information.

[0213] The transverse electric mode means that the electric field is completely within the cross-section of the waveguide, that is, the longitudinal component Ez of the electric field is 0, while the magnetic field has a longitudinal component Hz≠0. The electric field is perpendicular to the propagation direction of the wave, and the magnetic field includes transverse and longitudinal components. The transverse electric mode is common in microwave waveguides and optical fiber communications, used to transmit signals of specific frequencies, and has different cut-off frequency characteristics.

[0214] The transverse electric mode polarization is also called s polarization, and the direction of the electric field is perpendicular to the plane of incidence. When reflecting and refracting, the reflectivity of s polarization is related to the angle of incidence and is often used to reduce reflection losses (such as in the design of laser cavity mirrors).

[0215] The first polarization optical signal and the second polarization optical signal are generated in different modulation regions.

[0216] In one embodiment, the first polarization optical signal can be one of a linearly polarized optical signal, a circularly polarized optical signal, or an elliptically polarized optical signal, and the second polarization optical signal can be another one of a linearly polarized optical signal, a circularly polarized optical signal, or an elliptically polarized optical signal.

[0217] In one embodiment, the first polarization optical signal and the second polarization optical signal can belong to the same polarization type but have different parameters. For example, both belong to linearly polarized optical signals but have different vibration directions or phase relationships; both belong to circularly polarized optical signals but have different rotation directions, amplitudes, or phases; both belong to elliptically polarized optical signals but have different major axis directions, ellipticities, rotation directions, amplitudes, or phases.

[0218] In one embodiment, the first modulation region of the modulation element is used to generate a third polarization optical signal with transverse magnetic mode polarization. The optical sensor is used to generate third polarization detection information conforming to the transverse magnetic mode polarization, and the third polarization detection information is used to generate first identification information.

[0219] In one embodiment, the second modulation region of the modulation element is used to generate a fourth polarization optical signal with transverse magnetic mode polarization. The optical sensor is used to generate fourth polarization detection information conforming to the transverse magnetic mode polarization, and the fourth polarization detection information is used to generate first identification information.

[0220] The transverse magnetic mode indicates that the longitudinal component of the magnetic field Hz = 0, while the electric field has a longitudinal component Ez ≠ 0. The magnetic field is completely transverse, and the electric field includes a longitudinal component. The transverse magnetic mode is used for energy transmission of specific modes in waveguide design, antennas, and dielectric resonators.

[0221] The transverse magnetic mode polarization is also called p-polarization, and the direction of the electric field is parallel to the plane of incidence. There is a Brewster angle for p-polarization, and the p-polarization component in the reflected light is completely transmitted, which is used in the design of polarization filters and optical coatings.

[0222] The third polarized light signal and the fourth polarized light signal are generated in different modulation regions.

[0223] In one embodiment, the third polarized light signal can be one of a linearly polarized light signal, a circularly polarized light signal, or an elliptically polarized light signal, and the fourth polarized light signal can be another of a linearly polarized light signal, a circularly polarized light signal, or an elliptically polarized light signal.

[0224] The third polarized light signal can be of the same type as the first polarized light signal, and the fourth polarized light signal can be of the same type as the second polarized light signal.

[0225] In one embodiment, the third polarized light signal and the fourth polarized light signal can belong to the same polarization type but have different parameters. For example, both belong to linearly polarized light signals but have different vibration directions or phase relationships; both belong to circularly polarized light signals but have different rotation directions, amplitudes, or phases; both belong to elliptically polarized light signals but have different major axis directions, ellipticities, rotation directions, amplitudes, or phases.

[0226] The third polarized light signal can have the same parameters as the first polarized light signal, and the fourth polarized light signal can have the same parameters as the second polarized light signal.

[0227] In one embodiment, the first polarized light signal is perpendicular to the incident light, and the second polarized light signal is perpendicular to the incident light. Specifically, the polarization direction of the first polarized light signal is perpendicular to the propagation direction of the incident light, and the polarization direction of the second polarized light signal is perpendicular to the propagation direction of the incident light.

[0228] In one embodiment, the third polarized light signal is perpendicular to the incident light, and the fourth polarized light signal is perpendicular to the incident light. Specifically, the polarization direction of the third polarized light signal is perpendicular to the propagation direction of the incident light, and the polarization direction of the fourth polarized light signal is perpendicular to the propagation direction of the incident light.

[0229] In a preferred embodiment, the propagation directions of the polarized light signals generated by the modulation element are all perpendicular to the incident light and are in the same plane.

[0230] In one embodiment, the optical sensor generates n polarization detection information corresponding to n polarized light signals respectively. The processor generates recognition information based on the operation of n polarization detection information and preset weight parameters.

[0231] The weight can be configured according to any of the foregoing technical solutions.

[0232] n is an integer greater than or equal to 2. The recognition information is determined by weighted operation of multiple polarization detection information, enabling multi-dimensional recognition.

[0233] In one embodiment, the loss value is cross-entropy loss or mean squared error.

[0234] Among them, cross-entropy loss can be used for binary classification, multi-classification, and multi-label classification problems, especially in scenarios where the output is a probability distribution. For example, it is applied to image classification (such as ResNet), text classification (such as BERT), spam detection, etc. Cross-entropy loss can be used in combination with the Softmax (multi-classification) or Sigmoid (binary classification) activation function.

[0235] Cross-entropy loss can directly measure the difference between the predicted probability distribution and the true distribution, is suitable for classification tasks, and has the advantages of being friendly to gradient optimization and avoiding gradient disappearance.

[0236] Mean squared error can be used to predict continuous values, such as numerical prediction, time series analysis, etc. For example, it is applied to house price prediction, temperature prediction, stock price prediction. The output of mean squared error can be any real value without being normalized to a probability.

[0237] Mean squared error directly measures the Euclidean distance between the predicted value and the true value, has a clear physical meaning, and has the advantages of being sensitive to outliers and being applicable to any continuous value prediction task.

[0238] In one embodiment, the optical component includes a modulation element, and the modulation element includes at least two modulation regions. When the at least two modulation regions are designed and updated based on the loss value, they have different weights.

[0239] The weights corresponding to different modulation regions can be set and adjusted according to the relevance of the modulation region to the current feature recognition task. When the first modulation region has a stronger relevance to the current feature recognition task, or when the corresponding first polarized light signal and the third polarized light signal have a stronger relevance to the current feature recognition task, it can be set that the first modulation region has a higher weight than the second modulation region. Such weight differences can be preset or formed during the update process.

[0240] In one embodiment, the optical sensor includes at least two regions for generating at least two polarization detection signals, and the at least two polarization detection signals have different weights when the design of the processor is updated based on the loss value.

[0241] The weights corresponding to different regions on the optical sensor can be set and adjusted according to the relevance of the region to the current feature recognition task. When the first region has a stronger relevance to the current feature recognition task, or the corresponding first polarization light signal has a stronger relevance to the current feature recognition task, it can be set that the first region has a higher weight than the second, third, or fourth region. Such a weight difference can be preset or formed during the update process.

[0242] In summary, the design method of the optical system provided in this application generates polarization detection information through optical components and an optical sensor. Based on the polarization detection information, the processor can obtain multi-dimensional feature recognition results; by comparing the recognition information determined by the optical system with the known feature information to determine the loss value, and combining the loss value to update the design of the processor or optical components, it is possible to perform end-to-end training on the optical system to ensure the recognition accuracy of the optical system; when updating the design of the optical components, the relationship between the design of the optical components and their outputs can be constructed through a relationship function to achieve end-to-end training of the optical components themselves for accurate recognition.

[0243] It should be understood that although this specification is described according to embodiments, not every embodiment only includes an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0244] The series of detailed descriptions listed above are only specific descriptions of the feasible embodiments of this application, and they are not used to limit the protection scope of this application. Any equivalent embodiments or changes made without departing from the technical spirit of this application should be included in the protection scope of this application.

Claims

1. A design method for an optical system, characterized in that, The optical system includes: an optical component configured to receive incident light from a subject under test and generate a polarized light signal; a light sensor disposed on the light output side of the optical component, the light sensor being configured to receive the polarized light signal and generate polarization detection information; a processor configured to generate identification information based on the polarization detection information; The design method includes: obtaining first identification information and first feature information, the first identification information being obtained by the optical system through feature recognition of the subject under test, and the first feature information representing the actual features of the same subject under test; determining a loss value based on the first identification information and the first feature information; updating the design of the processor based on the loss value, or updating the design of the optical component based on the loss value and a relationship function, or updating both the design of the optical component and the design of the processor based on the loss value and the relationship function, until the loss value meets a preset numerical condition to obtain the design information of the optical system; The relationship function characterizes the relationship between the output of the optical component and the design information of the optical component.

2. The design method according to claim 1, characterized in that The relationship function is a point spread function.

3. The design method according to claim 1, characterized in that, The optical component includes a modulation element configured to generate a polarized light signal, The modulation element includes a microstructure unit disposed at at least one of the light input side or the light output side of the modulation element.

4. The design method according to claim 1 or 3, characterized in that including at least one of the following: The optical component includes a lens, and the relationship function characterizes the relationship between the output of the optical component and the focal length of the lens; The optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the shape of the microstructure unit in the modulation element; The optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the size of the microstructure unit in the modulation element; The optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the material of the microstructure unit in the modulation element; The optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and the arrangement of the microstructure units in the modulation element; The optical component includes a modulation element, and the relationship function characterizes the relationship between the output of the optical component and a first distance, the first distance being the distance between the modulation element and the light sensor.

5. The design method according to claim 3, characterized in that The modulation element is configured to generate a first polarized light signal in a first region of the light sensor and a second polarized light signal in a second region of the light sensor; the design method includes at least one of the following: updating the design of the microstructure unit corresponding to the first region in the modulation element based on the loss value and a first relationship function, the first relationship function characterizing the relationship between the output of the optical component and the design information of the microstructure corresponding to the first region; updating the design of the microstructure unit corresponding to the second region in the modulation element based on the loss value and a second relationship function, the second relationship function characterizing the relationship between the output of the optical component and the design information of the microstructure corresponding to the second region.

6. The design method according to claim 3, characterized in that The modulation element includes a first modulation region and a second modulation region. The first modulation region includes microstructure units configured with first design information, and the second modulation region includes microstructure units configured with second design information. The first modulation region is used to generate a first polarized light signal and a third polarized light signal in a first region and a third region of the optical sensor respectively, and the second modulation region is used to generate a second polarized light signal and a fourth polarized light signal in a second region and a fourth region of the optical sensor respectively. The design method includes at least one of the following: Updating the first design information, updating the position of the first modulation region, or updating both the first design information and the position of the first modulation region based on a loss value and a first relationship function, where the first relationship function characterizes the relationship between the output of the optical component and the design information of the corresponding first modulation region, the position of the first modulation region, and the first polarized light signal; Updating the second design information, updating the position of the second modulation region, or updating both the second design information and the position of the second modulation region based on a loss value and a second relationship function, where the second relationship function characterizes the relationship between the output of the optical component and the design information of the corresponding second modulation region, the position of the second modulation region, and the second polarized light signal; Updating the first design information, updating the position of the first modulation region, or updating both the first design information and the position of the first modulation region based on a loss value and a third relationship function, where the third relationship function characterizes the relationship between the output of the optical component and the design information of the corresponding first modulation region, the position of the first modulation region, and the third polarized light signal; Updating the second design information, updating the position of the second modulation region, or updating both the second design information and the position of the second modulation region based on a loss value and a fourth relationship function, where the fourth relationship function characterizes the relationship between the output of the optical component and the design information of the corresponding second modulation region, the position of the second modulation region, and the fourth polarized light signal.

7. The design method according to claim 5 or 6, characterized in that, Including at least one of the following: The first modulation region of the modulation element is used to generate a first polarized light signal with transverse electric mode polarization; The optical sensor is used to generate first polarization detection information conforming to transverse electric mode polarization, and the first polarization detection information is used to generate first identification information; The second modulation region of the modulation element is used to generate a second polarized light signal with transverse electric mode polarization; The optical sensor is used to generate second polarization detection information conforming to transverse electric mode polarization, and the second polarization detection information is used to generate first identification information; The first modulation region of the modulation element is used to generate a third polarized light signal with transverse magnetic mode polarization; The optical sensor is used to generate third polarization detection information conforming to transverse magnetic mode polarization, and the third polarization detection information is used to generate first identification information; The second modulation region of the modulation element is used to generate a fourth polarized light signal with transverse magnetic mode polarization; The optical sensor is used to generate fourth polarization detection information conforming to transverse magnetic mode polarization, and the fourth polarization detection information is used to generate first identification information.

8. The design method according to claim 5 or 6, characterized in that The first polarized light signal is perpendicular to the incident light, and the second polarized light signal is perpendicular to the incident light.

9. The design method according to claim 1, characterized in that The optical sensor generates n polarization detection information corresponding to n polarized light signals respectively. The processor generates recognition information based on the operation of preset weight parameters according to n polarization detection information.

10. The design method according to claim 1, wherein It includes at least one of the following: The loss value is cross-entropy loss or mean square error; The optical component includes a modulation element, and the modulation element includes at least two modulation regions, and when the at least two modulation regions are updated based on the loss value, they have different weights; The optical sensor includes at least two regions for generating at least two polarization detection signals, and when the at least two polarization detection signals are used for the design update of the processor based on the loss value, they have different weights.

11. A surface feature analysis system, characterized in that, It includes: An optical component for receiving incident light from a subject to generate a polarized light signal, An optical sensor disposed on the light output side of the optical component, and the optical sensor is used for receiving the polarized light signal to generate polarization detection information, A processor for generating recognition information according to the polarization detection information; The surface feature analysis system includes one of the following: The design information of the processor is determined based on the loss value, the loss value is determined based on the recognition information and preset feature information, and the feature information represents the actual features of the corresponding subject; The design information of the optical component is determined based on the loss value and a relationship function, the loss value is determined based on the recognition information and preset feature information, the feature information represents the actual features of the corresponding subject, and the relationship function characterizes the relationship between the output of the optical component and the design information of the optical component; The design information of the surface feature analysis system is determined based on the loss value and a relationship function, the loss value is determined based on the recognition information and preset feature information, the feature information represents the actual features of the subject corresponding to the feature information, and the relationship function characterizes the relationship between the output of the optical component and the design information of the optical component.

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