Polarization imaging system, method and device based on pupil light splitting

Abstract

The invention relates to the technical field of polarization imaging, in particular to a polarization imaging system, method and device based on pupil light splitting, and the system comprises an optical imaging lens and an image sensor which are sequentially located in front of a target. A pupil light splitting assembly is arranged in the optical imaging lens; the pupil light splitting assembly is located at the position of an aperture diaphragm of the optical imaging lens and comprises a plurality of polaroids of different polarization states and a plurality of broadband filters of different working wavebands, the polaroids correspond to the broadband filters in a one-to-one mode, and joint coding of incident light polarization information and spectral information is achieved through arrangement of the pupil light splitting assembly. And the Stokes vector image of the target can be obtained by decoding the acquired image. Compared with an existing polarization imaging system, the system has the advantages of being small in size, high in imaging spatial resolution, low in cost and good in transportability, and the problems that simultaneous polarization imaging is high in spatial resolution loss, complex in system, high in cost and poor in transportability are solved.

Description

Technical Field

[0001] The present invention relates to the field of polarization imaging technology, and particularly to a polarization imaging system, method and device based on pupil splitting. Background Technique

[0002] Polarization imaging technology is an advanced optical detection technology that uses the different propagation and reflection characteristics of polarized light to obtain image information. Its basic principle is to select specific light polarization directions during the imaging process by using one or more polarization filters, thereby separating the polarization information of light. By measuring different polarization components of light, partial or all polarization state information of the measured light can be obtained. Through the analysis and calculation of these polarization information images, polarization parameter images such as degree of polarization, polarization angle, ellipticity angle, polarization transmission characteristics, depolarization characteristics, etc. can be obtained; by analyzing and processing these polarization information, additional image details and contrast can be obtained for analyzing various characteristic information such as the shape, roughness, medium characteristics, and even biochemistry of the measured object. Polarization imaging technology is a non-contact detection technology based on polarized light analysis, with advantages such as high sensitivity, enhanced contrast, and suppression of background noise, and is widely used in fields such as agriculture, environment, medicine, engineering, atmosphere, and astronomy.

[0003] The current polarization imaging systems are mainly divided into time-division type and simultaneous type. Among them, the time-division polarization imaging system places a continuously rotating linear polarizer in front of the detector, obtains images in each linear polarization direction in turn, and finally obtains the polarization characteristic image through calculation. Although this imaging method has a simple structure and low cost, since the polarization information is obtained by controlling the polarization element, there is a problem of asynchronous information acquisition, and it is impossible to realize real-time detection of dynamic scenes, and it is mainly applicable to the observation of static targets. The simultaneous polarization imaging system includes amplitude-division polarization imaging, aperture-division polarization imaging, and focal-plane-division polarization imaging; amplitude-division polarization imaging uses a beam-splitting element to split the reflected light into multiple channels, implements different polarization modulation schemes in each channel, and uses multiple detectors to simultaneously obtain multiple images of the same target scene, but there are problems such as too large system volume, complex overall structure, difficult optical path calibration, and large optical energy loss, resulting in low image contrast and low signal-to-noise ratio in low-light environments; aperture-division polarization imaging uses off-axis or eccentric multiple optical systems to detect the same target, places multiple imaging lenses off-axis at the system aperture to form multiple channels, places polarization elements in each channel, and obtains the intensity images of each polarization component through a single exposure. This method requires the design of multiple optical channels to obtain polarization information, resulting in loss of spatial resolution, and the system debugging is complex with large errors; focal-plane-division polarization imaging integrates a micro-polarization array with different polarization directions in front of the detector focal plane. Each photosensitive pixel of the detector corresponds to a micro-polarizer in one direction, and realizes single-exposure acquisition of images of the same target in different polarization directions. This method has a small volume, light weight, strong environmental adaptability, high stability and accuracy, but the loss of spatial resolution is large and the polarization imaging effect is poor. In 2019, Liang proposed a reconfigurable snapshot polarization imaging technology based on spectral polarization filtering (Liang J; Tian X; Ju H; Wang D; Wu H; Ren L; Liang R. Reconfigurable snapshot polarimetric imaging technique through spectral-polarization filtering[J]. Optics Letters, 2019, 44(18): 4574-4577). This technology realizes the polarization imaging effect while not losing the spatial resolution by placing a spectral-polarization filter at the aperture coding of the system. However, this technology has high requirements for the spectral reflectivity of the target by using the coding method of narrowband spectral filters. Therefore, in practical applications, it has high limitations and poor portability. Summary of the Invention

[0004] Aiming at the problems of high spatial resolution loss, complex system, high cost and poor portability in the existing technology for simultaneous polarization imaging, the present invention provides a polarization imaging system, method and device based on pupil splitting.

[0005] To achieve the above object, the present invention adopts the following technical solutions: The present invention provides a polarization imaging system based on pupil splitting, including an optical imaging lens and an image sensor successively located in front of the target. A pupil splitting component is arranged inside the optical imaging lens. The pupil splitting component is located at the aperture stop in the optical imaging lens and includes a plurality of polarizers with different polarization states and a plurality of broadband filters with different working bands, and the polarizers and the broadband filters correspond to each other one by one.

[0006] Optionally, both the polarizer and the broadband filter are set to 3.

[0007] Optionally, the polarizers have different polarization states.

[0008] Optionally, the image sensor is a color image sensor.

[0009] Optionally, the light transmission band of the broadband filter is within the response spectral band of the image sensor.

[0010] The present invention provides a polarization imaging method using the above polarization imaging system based on pupil splitting, including: Obtaining the optical characteristic parameters of the pupil splitting component and the incident light responses of different color channels of the image sensor; the optical characteristic parameters of the pupil splitting component include the transmittances of each polarizer and broadband filter and the polarization states of each polarizer. Obtaining a coded color image according to the optical characteristic parameters of the pupil splitting component and the incident light responses of different color channels of the image sensor. Decoding the coded color image to obtain the Stokes vector image of the target.

[0011] Further, the method for obtaining a coded color image according to the optical characteristic parameters of the pupil splitting component and the incident light responses of different color channels of the image sensor is:

[0012] Among them, represents the intensity of the light received by the image sensor; represents the transmittance; the subscript , and respectively represent the numbers of the corresponding polarizers; the subscript , and respectively represent the numbers of the corresponding broadband filters; the superscript is the red channel of the image sensor, and the superscript represents the green channel of the image sensor, and the superscript represents the blue channel of the image sensor; represents the light intensity of the reflected light of the target.

[0013] Furthermore, the method for decoding the encoded color image to obtain the Stokes vector image of the target is as follows: Assume that within the visible light wavelength range, the polarization state of the incident light of the same object point of the target is consistent and uniformly distributed. Then, the transmittance of the incident light of the corresponding image points in different color channels of the image sensor for the same polarizer is the same, that is:

[0014] Furthermore, it can be obtained that:

[0015] Combining the light intensities of the incident light in each color channel of the image sensor, decode the obtained encoded color image, calculate the transmittances of different polarizers, and obtain the Stokes vector image of the target.

[0016] A polarization imaging unit based on the above polarization imaging method includes: Optical parameter acquisition module: used to acquire the optical characteristic parameters of the pupil splitting component and the incident light responses of different color channels of the image sensor; the optical characteristic parameters of the pupil splitting component include the transmittances of each polarizer and broadband filter and the polarization states of each polarizer; Encoded color image acquisition module: used to obtain the encoded color image according to the optical characteristic parameters of the pupil splitting component and the incident light responses of different color channels of the image sensor; Stokes vector image acquisition module: used to decode the encoded color image to obtain the Stokes vector image of the target.

[0017] A terminal device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the above method are implemented.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a polarization imaging system based on pupil splitting, which includes an optical imaging lens and an image sensor that are sequentially located in front of the target; a pupil splitting component is arranged at the aperture stop inside the optical imaging lens; wherein, the optical imaging lens is configured to image the target on the image sensor; the pupil splitting component is configured to jointly encode the polarization information and spectral information of the incident light to obtain an encoded color image; by decoding the encoded color image, the Stokes vector image of the target can be obtained. Compared with the current polarization imaging systems, this system adopts a new splitting strategy. By inserting a pupil splitting component at the aperture stop of the system, the spectral and polarization information of the incident light are jointly modulated. Only one image with full pixel resolution needs to be captured to calculate the polarization image of the target scene, effectively improving the imaging resolution of the system; at the same time, the design of the pupil splitting component can match various optical imaging lenses. Therefore, it has the advantages of miniaturization, low cost, and good portability, and has broad application prospects and important research value in multiple fields such as remote sensing detection, biomedical imaging, and machine vision.

[0019] The present invention provides a polarization imaging method using the above-mentioned polarization imaging system based on pupil splitting. This method first obtains the optical characteristic parameters of the pupil splitting component and the incident light responses of different color channels of the image sensor; then, based on the optical characteristic parameters of the pupil splitting component and the incident light responses of different color channels of the image sensor, an encoded color image is obtained; finally, the encoded color image is decoded to obtain the Stokes vector image of the target. Among them, by obtaining parameters such as the optical characteristic parameters of the pupil splitting component and the incident light responses of different color channels of the image sensor, the accuracy of subsequent calculations and analyses is ensured, and the polarization imaging accuracy is improved; during the process of obtaining the encoded color image, by combining the incident light intensity information of different color channels (red channel, green channel, and blue channel) of the image sensor, the polarization information of the target reflected light is encoded in different color channels, ensuring that the captured encoded color image is an encoded color image with full pixel resolution, so that the encoded color image contains all the polarization information of the target reflected light; by decoding the encoded color image to obtain the Stokes vector image of the target, the polarization information of the target reflected light can be obtained simply and quickly. Compared with traditional polarization imaging methods, this method avoids complex polarization measurement and calculation processes, significantly reduces the computational complexity, improves the computational efficiency, is simple and flexible, and is of great significance for promoting the innovation and development of polarization imaging technology.

[0020] The present invention also provides a polarization imaging unit based on the above polarization imaging method. Through the highly integrated and modular design of the optical parameter acquisition module, encoded color image acquisition module, and Stokes vector image acquisition module in the polarization imaging unit, the process of obtaining the optical characteristic parameters of the pupil splitting component and the incident light response of different color channels of the image sensor, acquiring the encoded color image, and decoding the encoded color image to obtain the Stokes vector image of the target is realized. This polarization imaging unit has good stability, flexibility, and reliability, and has strong practical value.

[0021] The present invention also provides a terminal device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the above method are realized. The device has a simple structure, low transformation cost, and small resource occupation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic structural diagram of a polarization imaging system based on pupil splitting according to the present invention.

[0023] Figure 2 It is a schematic structural diagram of the polarizer of the pupil splitting component according to the present invention.

[0024] Figure 3 It is a schematic structural diagram of the broadband filter of the pupil splitting component according to the present invention.

[0025] Figure 4 It is a schematic structural diagram of the pupil splitting component according to the present invention.

[0026] Figure 5 It is a flow chart of the polarization imaging method according to the present invention.

[0027] Figure 6 It is a schematic structural diagram of the polarization imaging unit according to the present invention.

[0028] Among them, 1 - target, 2 - optical imaging lens, 3 - image sensor, 4 - pupil splitting component, 41 - polarizer, 42 - broadband filter. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0030] It should be noted that the terms "first", "second", etc. in the description, claims and above-mentioned drawings of the present invention are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0031] The present invention will be further described in detail below with reference to specific embodiments, which are explanations of the present invention rather than limitations.

[0032] See Figure 1 , the present invention discloses a polarization imaging system based on pupil splitting, which includes an optical imaging lens 2, a pupil splitting component 4 and an image sensor 3; The optical imaging lens 2 is arranged in front of the target 1 and is used to image the object of the target 1 on the image sensor 3. The inside of the optical imaging lens 2 is mainly composed of various optical elements such as lenses and diaphragms. Among them, the lens is the most core part of the optical imaging lens 2 and is responsible for the refraction and focusing of light, converging the light from the outside into a clear image. The aperture stop is located inside the optical imaging lens 2, and controls the intensity and angle of the incident light by contracting and expanding the aperture, thereby adjusting the exposure and depth of field of the image; See Figures 2 to 4 , the pupil splitting component 4 is used for the joint encoding of the polarization information and spectral information of the incident light. The pupil splitting component 4 is located at the aperture stop inside the optical imaging lens 2 and includes a plurality of polarizers 41 with different polarization states and a plurality of broadband filters 42 with different working bands. The polarizers 41 and the broadband filters 42 are in one-to-one correspondence. Preferably, the input end of the broadband filter 42 is connected to the output end of the polarizer 41; the polarizers 41 and the broadband filters 42 are closely attached in one-to-one correspondence. The polarizer 41 is used for analyzing the polarization state of the incident light, and the broadband filter 42 is used for spectral encoding of the analyzed light; preferably, 3 polarizers 41 are provided and 3 broadband filters 42 are provided; the polarizers 41 have different polarization states. Further preferably, the combination of the polarizers 41 includes a 0°, 45° and 90° combination, a 0°, 60° and 120° combination or a 0°, 90° and right-handed circular polarization state combination; the light passing band (half-width greater than 40 nm) of the broadband filter 42 is within the response spectral range of the image sensor 3; The image sensor 3 is a color image sensor, located at the rear end of the optical imaging lens 2, and is used to sense incident light and record color images.

[0033] Taking the combination of the polarization directions of the polarizer 41 as 0°, 45°, and 90° as an example, the polarization image resolution method based on this system is as follows: The incident light is subjected to polarization spectral joint modulation by the pupil splitting component 4 at the aperture stop of the optical imaging lens 2, so that the incident light first passes through the polarization modulation plane of the polarizer 41. At this time, the analyzed light is as follows:

[0034] Among them, represents the intensity of the analyzed light, represents the transmittance; the subscript 、 and respectively represent the corresponding polarizer 41 numbers, and the superscripts 、 and respectively represent the color channels of the image sensor 3. The color channels of the image sensor 3 include a red channel, a green channel, and a blue channel, where represents the red channel, represents the green channel and represents the blue channel; represents the reflected light intensity of the target 1; After passing the analyzed light through the broadband filter 42 of the pupil splitting component 4, an encoded color image can be obtained at the image sensor 3, and the light intensity of the obtained encoded color image is:

[0035] Among them, is the intensity of the light received by the image sensor 3; the subscripts 、 and respectively represent the corresponding broadband filter 42 numbers; In addition, assuming that the polarization state of the reflected light of the same object point of the target 1 is consistent and uniformly distributed within the visible light wavelength range (400nm - 700nm), the transmittance of the analyzed light of the corresponding image points in different color channels for the same polarizer 41 is the same, that is:

[0036] Substituting formula (3) into formula (2) can obtain:

[0037] When the polarization directions of the polarizer 41 are 0°, 45°, and 90° respectively, it is obtained that:

[0038] As can be seen from the above formula, by combining the light intensities of the incident light in each color channel of the image sensor 3 and decoding the encoded color image, the transmittances of different polarizers 41 can be calculated, and then the Stokes vector image of the target 1 can be obtained.

[0039] This system places a pupil splitting component 4 at the aperture stop in the optical imaging lens 2. The incident light of the target 1 is jointly encoded in polarization spectrum by the pupil splitting component 4, and an encoded color image is obtained on the image sensor 3. By decoding the obtained encoded color image, the transmittances of different polarizers 41 can be solved, and thus the Stokes vector image of the target 1 can be solved. This system adopts a broadband filter 42 and a new calculation model, which not only solves the problem that the spatial resolution will be lost in simultaneous polarization imaging, but also is applicable to all types of targets 1, with strong practical value. In addition, a more flexible selection of the broadband filter 42 can be supported.

[0040] See Figure 5 , the present invention provides a polarization imaging method using the above polarization imaging system based on pupil splitting, including: S1: Obtain the optical characteristic parameters of the pupil splitting component 4 and the incident light responses of different color channels of the image sensor 3; the optical characteristic parameters of the pupil splitting component 4 include the transmittances of each polarizer 41 and the broadband filter 42 and the polarization states of each polarizer 41. S2: Obtain an encoded color image according to the optical characteristic parameters of the pupil splitting component 4 and the incident light responses of different color channels of the image sensor 3, specifically:

[0041] Wherein, represents the intensity of the light received by the image sensor 3; represents the transmittance; the subscripts , and respectively represent the numbers of the corresponding polarizers 41; the subscripts , and respectively represent the numbers of the corresponding broadband filters 42; the superscripts , and respectively represent the color channels of the image sensor 3, is the light intensity of the reflected light of the target 1.

[0042] S3: Decode the encoded color image to obtain the Stokes vector image of the target 1, specifically: Assume that within the visible light wavelength range (400nm - 700nm), the polarization states of the incident light at the same object point of target 1 are consistent and uniformly distributed. Then, the transmittances of the incident light at the corresponding image points of different color channels of image sensor 3 with respect to the same polarizer 41 are the same, that is:

[0043] Furthermore, it can be obtained that:

[0044] Combined with the light intensities of the incident light in each color channel of image sensor 3, by decoding the encoded color image, the transmittances of different polarizers 41 can be calculated, and then the Stokes vector image of target 1 can be obtained.

[0045] This method avoids complex polarization measurement and calculation processes, significantly reduces the computational complexity, and improves the computational efficiency; the method is simple and has good flexibility, which is of great significance for promoting the innovation and development of polarization imaging technology.

[0046] Refer to Figure 6 , the present invention also provides a polarization imaging unit based on the above polarization imaging method, including: Optical parameter acquisition module: used to acquire the optical characteristic parameters of the pupil splitting component 4 and the incident light responses of different color channels of image sensor 3; the optical characteristic parameters of the pupil splitting component 4 include the transmittances of each polarizer 41 and broadband filter 42 and the polarization states of each polarizer 41; Encoded color image acquisition module: used to obtain an encoded color image according to the optical characteristic parameters of the pupil splitting component 4 and the incident light responses of different color channels of image sensor 3; Stokes vector image acquisition module: used to decode the encoded color image to obtain the Stokes vector image of target 1.

[0047] This imaging unit highly integrates each module, adopts a new calculation model, has good stability and reliability, and can be applied to multiple fields such as remote sensing detection, biomedical imaging, and machine vision.

[0048] The present invention provides a terminal device including: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps in each of the above method embodiments are implemented. Or, when the processor executes the computer program, the functions of each module / unit in each of the above device embodiments are implemented.

[0049] The computer program can be divided into one or more modules / units, which are stored in the memory and executed by the processor to implement the present invention.

[0050] The terminal device can be a computing device such as a desktop computer, a notebook, a palm computer, and a cloud server. The terminal device may include, but is not limited to, a processor and a memory.

[0051] The processor may be a central processing unit (CPU), or may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0052] The memory can be used to store the computer program and / or modules. By running or executing the computer program and / or modules stored in the memory, and by invoking the data stored in the memory, the terminal device can implement various functions.

[0053] If the modules / units integrated in the terminal device are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, to implement all or part of the processes in the above-described embodiment methods of the present invention, it can also be completed by a computer program instructing relevant hardware. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of the above-described method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file, or some intermediate form, etc. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disc, computer memory, read-only memory, random access memory, electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content included in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0054] The above are only the preferred embodiments of the present invention and are not intended to limit the technical solutions of the present invention. Those skilled in the art should understand that without departing from the spirit and principle of the present invention, the technical solutions can be subject to several simple modifications and substitutions, and these modifications and substitutions also fall within the protection scope covered by the claims.

Claims

1. A polarization imaging system based on pupil spectrometry, characterized in that: It includes an optical imaging lens (2) and an image sensor (3) which are sequentially located in front of a target (1); A pupil beam splitting component (4) is arranged inside the optical imaging lens (2); The pupil spectroscopic component (4) is located at the aperture stop in the optical imaging lens (2), and comprises a plurality of polarizing plates (41) with different polarization states and a plurality of broadband filters (42) with different operating bands, wherein the polarizing plates (41) correspond to the broadband filters (42) one by one.

2. The polarization imaging system based on pupil spectrometry according to claim 1, characterized in that: The number of the polarizing plates (41) and the number of the broadband filters (42) are both three.

3. The polarization imaging system based on pupil spectrometry according to claim 1, characterized in that: The polarizers (41) have different polarization states.

4. The polarization imaging system based on pupil spectrometry according to claim 1, characterized in that: The image sensor (3) is a color image sensor.

5. The polarization imaging system based on pupil spectrometry according to claim 1, characterized in that: The light transmission band of the broadband filter (42) is within the response spectrum of the image sensor (3).

6. A polarization imaging method using the polarization imaging system based on pupil spectrometry according to any one of claims 1 to 5, characterized in that: include: Acquiring optical characteristic parameters of the pupil spectroscopic component (4) and incident light responses of different color channels of the image sensor (3); the optical characteristic parameters of the pupil spectroscopic component (4) include the transmittance of each polarizer (41) and the broadband filter (42) and the polarization state of each polarizer (41); Obtaining a coded color image according to the optical characteristic parameters of the pupil spectroscopic component (4) and the incident light response of different color channels of the image sensor (3); Decode the coded color image and obtain the Stokes vector image of the target (1).

7. The polarization imaging method according to claim 6, characterized in that: The method for obtaining a coded color image according to the optical characteristic parameters of the pupil spectroscopic component (4) and the incident light response of different color channels of the image sensor (3) is: in, represents the intensity of light received by the image sensor (3); represents transmittance; subscript , and Respectively represent the numbers of the corresponding polarizers (41); , and denote the numbers of the corresponding broadband filters (42); the superscript is the red channel of the image sensor (3), with the superscript represents the green channel of the image sensor (3), with the superscript represents the blue channel of the image sensor (3); Indicates the intensity of the reflected light from the target (1).

8. The polarization imaging method according to claim 7, characterized in that: The method of decoding the coded color image to obtain the target Stokes vector image is: Assuming that within the visible light wavelength range, the polarization state of the incident light at the same object point of the target (1) is consistent and uniformly distributed, then the incident light at the corresponding image points of different color channels of the image sensor (3) has the same transmittance for the same polarizer (41), that is: Then we get: The intensity of the incident light in each color channel of the image sensor (3) is combined to decode the obtained coded color image, calculate the transmittance of different polarizers (41), and obtain a Stokes vector image of the target (1).

9. A polarization imaging unit based on the polarization imaging method according to any one of claims 6 to 8, characterized in that: include: An optical parameter acquisition module: used to acquire optical characteristic parameters of the pupil spectroscopic component (4) and incident light responses of different color channels of the image sensor (3); the optical characteristic parameters of the pupil spectroscopic component (4) include the transmittance of each polarizer (41) and the broadband filter (42) and the polarization state of each polarizer (41); A coded color image acquisition module: used for acquiring a coded color image according to the optical characteristic parameters of the pupil spectroscopic component (4) and the incident light response of different color channels of the image sensor (3); Stokes vector image acquisition module: used to decode the coded color image to obtain the Stokes vector image of the target (1).

10. A terminal device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 6 to 8 are implemented.

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