Self-calibrated polarization state measurement device and method based on trust region reflection method

Abstract

The self-calibrating polarization state measurement device and method based on the trust-domain reflection method belongs to the field of precision instrument manufacturing and measurement technology. The device includes an incident optical fiber, a collimator, a magneto-optical crystal module, a quarter-wave plate, an analyzer, an output optical fiber, and a packaging shell. The method obtains 16 output optical powers by changing the rotation angle of the four magneto-optical crystal modules. It uses an optical power meter to measure and processes the data using a trust-domain reflection optimization mathematical model and algorithm. It can realize the self-calibration of the polarization state measurement device and analyze the polarization state of the input light, and can overcome the influence of temperature, wavelength, assembly and measurement errors, and noise on the measurement accuracy.

Description

Technical Field

[0001] This invention belongs to the field of precision instrument manufacturing and measurement technology, and relates to a self-calibrating polarization state measurement device and method based on the trust region reflection method. Background Technology

[0002] With the continuous development of aerospace, optical technology, electronics, and other cutting-edge industries, polarization state analysis is becoming increasingly important in various applications. When using instruments for polarization-based measurements, the polarization state changes during propagation due to the influence of the propagation medium's properties, leading to uncertainties and errors in the measurement results. Therefore, when performing polarization measurements, the influence of the internal medium properties of the polarization state measurement instrument on the polarization state must be considered to ensure the accuracy and reliability of the measurement results. Commonly used methods include Fourier transform-based methods and retarder-based polarization measurement devices for analysis, but these methods utilize numerous optical components, increasing the cost of measurement. The Mueller matrix can characterize the propagation characteristics of light within a polarization measurement instrument. Calibrating the Mueller matrices of each optical component within the instrument can improve the accuracy of polarization state measurements.

[0003] Currently, the main methods for calibrating polarization state measurement instruments include the following:

[0004] 1. Xiaojun Chen et al. from General Optics in the United States used a waveplate analyzer and an optical rotator to characterize linear delay devices. This all-solid-state device can achieve high-precision measurement of the linear delay and optical axis orientation of waveplates.

[0005] 2. Vitaly Wirthl et al. from Cornell University in the United States designed a self-calibrating polarization measurement instrument to measure the Stokes vector of polarized light.

[0006] 3. Yao Xiaotian and others from the Optical Polarization Research Center of Tianjin University, China, designed a binary polarization analyzer to analyze the polarization state of input light.

[0007] In summary, by using a specially designed polarization analysis device with a known Mueller matrix, the polarization state of the input light can be analyzed by measuring certain parameters of the output light. This method has gained widespread application due to its simple structure and low cost, but some problems still exist:

[0008] 1. The optical parameters inside the polarization analysis device are affected by the environment and the tolerance of the device parameters. For example, the rotation angle of the magneto-optical crystal and the delay angle of the waveplate change with temperature and wavelength, which in turn affects the measurement accuracy of the polarization state. Therefore, it is necessary to obtain accurate optical parameters under the measurement state.

[0009] 2. Assembly errors exist in the optical components inside the polarization analysis device, which affect the measurement accuracy of the polarization state. It is necessary to obtain accurate assembly errors and then perform data compensation when analyzing the polarization state.

[0010] 3. During data acquisition using a polarization analysis device, measurement errors and noise from the acquisition device affect the accuracy of polarization state measurement, and their impact on the polarization state measurement results must be reduced. Summary of the Invention

[0011] The purpose of this invention is to propose a low-cost, self-calibrating polarization state measurement device and method. This method calibrates the internal device parameters and assembly errors of the polarization state measurement instrument, overcomes the influence of temperature and wavelength on device parameters, and suppresses measurement errors and noise, thereby achieving self-calibration and high-precision polarization state analysis of the polarization state measurement device. This invention designs a self-calibrating polarization state measurement device, which consists of two collimators, four magneto-optical crystal modules, a quarter-wave plate, and an analyzer. Each magneto-optical crystal module includes an optically rotating crystal and a magnetic field loading device. By changing the rotation angle of the optically rotating crystal through the magnetic field loading device, known and different combinations of polarization transmission characteristics can be generated. By measuring the optical power of the output light, the self-calibration of the polarization state measurement device and the analysis of the polarization state of the input light can be achieved. Furthermore, based on the designed self-calibrating polarization state measurement device, this invention proposes a method for solving the optimal solution of the internal optical device parameters of the polarization state measurement device using the trust region reflection method. This method can quickly complete polarization state measurement and self-calibration of the polarization state measurement device, including the rotation angle φ of the optically rotating crystal, the delay angle Γ of the quarter-wave plate, and the relative positioning angle θ between the quarter-wave plate and the polarizer. p .

[0012] The working principle of this invention is as follows: the light to be measured is input into the self-calibrating polarization state measurement device through an optical fiber. The polarization transmission characteristics of the self-calibrating polarization state measurement device are changed by changing the rotation angle of the magneto-optical crystal module. Each magneto-optical crystal module has two working states, φ and -φ. There are a total of 16 combinations of optical rotation angles of the four magneto-optical crystal modules. The optical power of the output light of the self-calibrating polarization state measurement device in the 16 states is measured. After signal processing by the self-calibrating polarization state measurement method based on the trust region reflection method, the calibration of the internal optical device parameters and high-precision polarization state analysis are completed.

[0013] The technical solution of this invention is: a self-calibrated polarization state measurement device and method based on the trust region reflection method, comprising an incident optical fiber, a collimator I, a magneto-optical crystal module I, a magneto-optical crystal module II, a quarter-wave plate, a magneto-optical crystal module III, a magneto-optical crystal module IV, an analyzer, a collimator II, an exiting optical fiber, and a packaging shell. The characteristic feature is that the light to be measured sequentially passes through the incident optical fiber, collimator I, magneto-optical crystal module I, magneto-optical crystal module II, quarter-wave plate, magneto-optical crystal module III, magneto-optical crystal module IV, and analyzer before exiting from the exiting optical fiber. The incident optical fiber is a single-mode optical fiber, and the exiting optical fiber is a single-mode optical fiber or a polarization-maintaining optical fiber. The transmission polarization direction of the analyzer is perpendicular to the fast axis direction of the quarter-wave plate. The magneto-optical crystal module I, magneto-optical crystal module II, magneto-optical crystal module III, magneto-optical crystal module IV, and analyzer are specified. The optical rotation angles of Module 2, Module 3, and Module 4 are positive counterclockwise and negative clockwise. Module 1, Module 2, Module 3, and Module 4 consist of an internal optical rotation crystal and a magnetic field loading device. The magnetic field loading device can apply saturated magnetic fields in both directions to the optical rotation crystal. It can independently control the application of the saturated magnetic field to the optical rotation crystal by the internal magnetic field loading device of Module 1, Module 2, Module 3, and Module 4 to control its optical rotation angle. The optical rotation angle has two working states: φ or -φ. The optical rotation angle value φ is an angle between 0 degrees and 360 degrees, excluding 0 degrees, 45 degrees, 90 degrees, and 180 degrees.

[0014] A self-calibrated polarization state measurement method based on the trust region reflection method is proposed. The light to be measured enters a self-calibrated polarization state measurement device, as shown above. The emitted light from the self-calibrated polarization state measurement device enters an optical power meter, and the optical power of the emitted light is measured. Then, data processing is performed according to the following steps to complete the self-calibration of the self-calibrated polarization state measurement device and the polarization state measurement:

[0015] Step 1: By changing the combination of the optical rotation angles of magneto-optical crystal modules 1, 2, 3, and 4, and measuring the optical power of the emitted light using an optical power meter, we can determine the optical power. Magneto-optical crystal modules 1, 2, 3, and 4 each have two operating states: φ and -φ. There are a total of 16 combinations of optical rotation angles for the four magneto-optical crystal modules. The optical power under each combination is measured and denoted as... The optical power measurement results are combined into an optical power matrix. T is the transpose symbol;

[0016] Step 2, the measurement equation of the self-calibrated polarization state measurement device based on the trust region reflection method is as follows: , The first row of the Mueller matrix represents the self-calibrating polarization state measurement device for measuring the optical rotation angles of magneto-optical crystal modules 1, 2, 3, and 4 under 16 combinations. Each row vector is related to the total optical rotation angle Ф1 of magneto-optical crystal module one and magneto-optical crystal module two, the total optical rotation angle Ф2 of magneto-optical crystal module three and magneto-optical crystal module four, the delay angle Γ of the quarter-wave plate, and the angle θ between the transmission polarization direction of the analyzer and the fast axis direction of the quarter-wave plate. p related, The row vector expression for the i-th combination is:

[0017]

[0018] In the formula, Ф1 and Ф2 take values ​​of 2φ, 0, and -2φ, respectively. φ and θ... p Using Γ as parameters to be optimized, the measurement equations of the self-calibrated polarization state measurement device are iteratively solved using the trust region reflection method. The optimal solution, the optimization objective of the trust region reflection method is to make The norm reaches its minimum value. The Stokes vector characterizing the polarization state of the light to be measured;

[0019] Step 3: Iteratively solve the measurement equations of the self-calibrated polarization state measurement device using the trust region reflection method. The optimal solutions φ and θ p Γ represents the calibration result of the self-calibrating polarization state measurement device. The Stokes vector characterizing the polarization state of the light under test can be expressed by the least squares matrix representation. Calculations are performed to analyze the polarization state of the light under test.

[0020] In the iterative process of the trust region reflection method in step 2, the formula for calculating the objective function is as follows: , For the nth iteration, φ and θ p The matrix formed by the optimization results of Γ, Let n be the Stokes vector of the light to be measured in the nth iteration. The expression is .

[0021] When the light to be measured is known to be completely polarized, the optimization objective of the second step, the trust region reflection method, is to make... The norm reaches a minimum value, and S0, S1, S2 and S3 are elements in the Stokes vector that characterizes the photometric polarization state.

[0022] Step 2 of the trust region reflection method involves setting the parameters to be optimized, φ and θ, during the iteration. p The optimization results of Γ take values ​​within the trust region radius, and the optimization parameters φ and θ are...p The optimized values ​​of Γ should be set within the tolerance range indicated in the reference device manual or based on empirical estimation. When setting, the values ​​should be 20% to 30% greater than the tolerance range or empirical estimation range.

[0023] The advantages of this invention are:

[0024] 1. The self-calibrated polarization state measurement device and method based on the trust region reflection method has the characteristics of high accuracy, low cost, small size, simple structure and short measurement time.

[0025] 2. A self-calibrating polarization state measurement device and method based on the trust region reflection method has the characteristics of fast convergence speed and high solution accuracy when optimizing the solution of the internal optical device parameters and the polarization state of the input light in the self-calibrating polarization state measurement device.

[0026] 3. A self-calibrating polarization state measurement device and method based on the trust region reflection method can simultaneously complete the calibration of the self-calibrating polarization state measurement device and the analysis of the polarization state of the input light, and can overcome the influence of temperature, input light wavelength, assembly error, measurement error and noise on the accuracy of polarization analysis. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of a self-calibrated polarization state measurement device based on the trust region reflection method;

[0028] In the diagram: 101. Incident fiber, 102. Collimator 1, 103. Magneto-optical crystal module 1, 104. Magneto-optical crystal module 2, 105. Quarter-wave plate, 106. Magneto-optical crystal module 3, 107. Magneto-optical crystal module 4, 108. Analyzer, 109. Collimator 2, 110. Outgoing fiber, 111. Encapsulation housing.

[0029] Figure 2 This is a schematic diagram of a magneto-optical crystal module;

[0030] In the figure: 201. Magnetic field loading device, 202. Optical crystal.

[0031] Figure 3 It refers to the angular relationship between the components inside the self-calibrating polarization state measurement device along the projection direction of the outgoing optical fiber.

[0032] In the diagram: 301. Transmission polarization direction of the analyzer; 302. Rotation angle of the magneto-optical crystal, counterclockwise is positive and clockwise is negative; 303. Fast axis direction of the quarter-wave plate.

[0033] Figure 4 This is a schematic diagram of a self-calibrating polarization state measurement device used for polarization state measurement;

[0034] In the figure: 401. Light source to be tested, 402. Self-calibrating polarization state measurement device, 403. Optical power meter. Detailed Implementation

[0035] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings:

[0036] A self-calibrated polarization state measurement device based on the trust region reflection method includes an incident fiber 101, a collimator 102, a magneto-optical crystal module 103, a magneto-optical crystal module 2 104, a quarter-wave plate 105, a magneto-optical crystal module 3 106, a magneto-optical crystal module 4 107, an analyzer 108, a collimator 2 109, an exit fiber 110, and a packaging shell 111. The device is characterized in that the light to be measured sequentially passes through the incident fiber 101 and the collimator 102. Magneto-optical crystal module 103, magneto-optical crystal module 204, quarter-wave plate 105, magneto-optical crystal module 306, magneto-optical crystal module 407, and analyzer 108 exit from output fiber 110. Input fiber 101 is single-mode fiber, and output fiber 110 is either single-mode fiber or polarization-maintaining fiber. The transmission polarization direction 301 of analyzer 108 is perpendicular to the fast axis direction 303 of quarter-wave plate 105. It is specified that magneto-optical crystal module 103, magneto-optical crystal module 204, quarter-wave plate 105, magneto-optical crystal module 306, magneto-optical crystal module 407, and analyzer 108 exit from output fiber 110. The optical rotation angle 302 of crystal module 2 (104), magneto-optical crystal module 3 (106), and magneto-optical crystal module 4 (107) is positive counterclockwise and negative clockwise. Magneto-optical crystal modules 1 (103), 2 (104), 3 (106), and 4 (107) consist of an internal optical rotation crystal 202 and a magnetic field loading device 201. The magnetic field loading device 201 can apply saturated magnetic fields in both directions to the optical rotation crystal 202, enabling independent optical rotation. The magnetic field loading device 201 inside the magneto-optical crystal module 103, magneto-optical crystal module 204, magneto-optical crystal module 306, and magneto-optical crystal module 4107 applies a saturated magnetic field to the optical rotation crystal 202 to control its optical rotation angle 302. The optical rotation angle 302 has two working states with optical rotation angle values ​​of φ or -φ. The optical rotation angle value φ of the optical rotation angle 302 is an angle between 0 degrees and 360 degrees, excluding 0 degrees, 45 degrees, 90 degrees, and 180 degrees.

[0037] A self-calibrated polarization state measurement method based on the trust region reflection method is disclosed. The light to be measured 401 enters a self-calibrated polarization state measurement device 402 (as described above). The emitted light from the self-calibrated polarization state measurement device 402 enters an optical power meter 403, and the optical power of the emitted light is measured. Then, data processing is performed according to the following steps to complete the self-calibration of the self-calibrated polarization state measurement device and the polarization state measurement:

[0038] Step 1: By changing the combination of the optical rotation angle 302 of magneto-optical crystal modules 1-103, 104-106, 107-106, and 4-107, and measuring the optical power of the emitted light using an optical power meter 403, each module has two operating states: φ or -φ. There are a total of 16 combinations of the optical rotation angle 302 for the four magneto-optical crystal modules. The optical power under each combination is measured and denoted as... The optical power measurement results are combined into an optical power matrix. T is the transpose symbol;

[0039] Step 2, the measurement equation of the self-calibrated polarization state measurement device based on the trust region reflection method is as follows: , The matrix formed by the first row of the Mueller matrix of the self-calibrating polarization state measurement device 402 for the optical rotation angle 302 of magneto-optical crystal module 103, magneto-optical crystal module 204, magneto-optical crystal module 306, and magneto-optical crystal module 407 under 16 combinations is shown. Each row vector is associated with the total optical rotation angle Ф1 of magneto-optical crystal module 103 and magneto-optical crystal module 204, the total optical rotation angle Ф2 of magneto-optical crystal module 306 and magneto-optical crystal module 407, the delay angle Γ of quarter-wave plate 105, and the angle θ between the transmission polarization direction 301 of analyzer 108 and the fast axis direction 303 of quarter-wave plate 105. p related, The row vector expression for the i-th combination is:

[0040] ,

[0041] In the formula, Ф1 and Ф2 take values ​​of 2φ, 0, and -2φ, respectively. φ and θ... p Using Γ as parameters to be optimized, the measurement equations of the self-calibrated polarization state measurement device are iteratively solved using the trust region reflection method. The optimal solution, the optimization objective of the trust region reflection method is to make The norm reaches its minimum value. The Stokes vector characterizing the polarization state of the light to be measured;

[0042] Step 3: Iteratively solve the measurement equations of the self-calibrated polarization state measurement device using the trust region reflection method. The optimal solutions φ and θ p Γ represents the calibration result of the self-calibrated polarization state measurement device 402. The Stokes vector characterizing the polarization state of the light under test can be expressed by the matrix representation of the least squares method. Calculations are performed to analyze the polarization state of the light under test.

[0043] In the iterative process of the trust region reflection method in step 2, the formula for calculating the objective function is as follows: , For the nth iteration, φ and θ p The matrix formed by the optimization results of Γ, Let n be the Stokes vector of the light to be measured in the nth iteration. The expression is .

[0044] When the light to be measured is known to be completely polarized, the optimization objective of the second step, the trust region reflection method, is to make... The norm reaches a minimum value, and S0, S1, S2 and S3 are elements in the Stokes vector that characterizes the photometric polarization state.

[0045] Step 2 of the trust region reflection method involves setting the parameters to be optimized, φ and θ, during the iteration. p The optimization results of Γ take values ​​within the trust region radius, and the optimization parameters φ and θ are... p The optimized values ​​of Γ should be set within the tolerance range indicated in the reference device manual or based on empirical estimation. When setting, the values ​​should be 20% to 30% greater than the tolerance range or empirical estimation range.

[0046] The working process of this invention is as follows:

[0047] The light under test 401 enters the self-calibrating polarization state measurement device 402 through the incident fiber 101, and then passes sequentially through the incident fiber 101, collimator 102, magneto-optical crystal module 103, magneto-optical crystal module 2 104, quarter-wave plate 105, magneto-optical crystal module 3 106, magneto-optical crystal module 4 107, and analyzer 108 before exiting through the exit fiber 110 and entering the optical power meter 403 to measure the optical power of the exit light. The data is then processed according to the following steps to complete the self-calibration and polarization state measurement of the self-calibrating polarization state measurement device:

[0048] Step 1: By changing the combination of the optical rotation angle 302 of magneto-optical crystal modules 1-103, 104-106, 107-106, and 4-107, and measuring the optical power of the emitted light using an optical power meter 403, each module has two operating states: φ or -φ. There are a total of 16 combinations of the optical rotation angle 302 for the four magneto-optical crystal modules. The optical power under each combination is measured and denoted as... The optical power measurement results are combined into an optical power matrix. T is the transpose symbol;

[0049] Step 2, the measurement equation of the self-calibrated polarization state measurement device based on the trust region reflection method is as follows: , The matrix formed by the first row of the Mueller matrix of the self-calibrating polarization state measurement device 402 for the optical rotation angle 302 of magneto-optical crystal module 103, magneto-optical crystal module 204, magneto-optical crystal module 306, and magneto-optical crystal module 407 under 16 combinations is shown. Each row vector is associated with the total optical rotation angle Ф1 of magneto-optical crystal module 103 and magneto-optical crystal module 204, the total optical rotation angle Ф2 of magneto-optical crystal module 306 and magneto-optical crystal module 407, the delay angle Γ of quarter-wave plate 105, and the angle θ between the transmission polarization direction 301 of analyzer 108 and the fast axis direction 303 of quarter-wave plate 105. p related, The row vector expression for the i-th combination is:

[0050] ,

[0051] In the formula, Ф1 and Ф2 take values ​​of 2φ, 0, and -2φ, respectively. φ and θ... p Using Γ as parameters to be optimized, the measurement equations of the self-calibrated polarization state measurement device are iteratively solved using the trust region reflection method. The optimal solution, the optimization objective of the trust region reflection method is to make The norm reaches its minimum value. The Stokes vector characterizing the polarization state of the light to be measured;

[0052] Step 3: Iteratively solve the measurement equations of the self-calibrated polarization state measurement device using the trust region reflection method. The optimal solutions φ and θ p Γ represents the calibration result of the self-calibrated polarization state measurement device 402. The Stokes vector characterizing the polarization state of the light under test can be expressed by the matrix representation of the least squares method. Calculations are performed to analyze the polarization state of the light under test.

[0053] The technological innovations and beneficial effects of the self-calibrating polarization state measurement device and method based on the trust-region reflection method are as follows: When the accurate parameters of the internal optical components of the self-calibrating polarization state measurement device are unknown or assembly errors exist, the device and method can obtain accurate parameters of the internal optical components and the precise polarization state of the light under test. Furthermore, it can overcome the influence of ambient temperature and the wavelength of the light under test on the accuracy of polarization state measurement. Simultaneously, the self-calibrating polarization state measurement device and method propose new optimization objectives and processes, and utilize trust-region optimization algorithms and least squares algorithms to suppress the influence of optical power noise and measurement errors on the polarization state measurement results. In addition, the self-calibrating polarization state measurement device and method have the advantages of simple structure, low cost, small size, high accuracy, and fast measurement speed.

Claims

1. A self-calibrated polarization state measurement device based on the trust region reflection method, comprising an incident optical fiber (101), a collimator one (102), a magneto-optical crystal module one (103), a magneto-optical crystal module two (104), a quarter-wave plate (105), a magneto-optical crystal module three (106), a magneto-optical crystal module four (107), an analyzer (108), a collimator two (109), an output optical fiber (110), and a packaging shell (111), characterized in that... The light to be tested passes sequentially through the incident fiber (101), collimator one (102), magneto-optical crystal module one (103), magneto-optical crystal module two (104), quarter-wave plate (105), magneto-optical crystal module three (106), magneto-optical crystal module four (107), and analyzer (108) before exiting from the output fiber (110). The incident fiber (101) is a single-mode fiber, and the output fiber (110) is a single-mode fiber or a polarization-maintaining fiber. The transmission polarization direction (301) of the analyzer (108) is perpendicular to the fast axis direction (303) of the quarter-wave plate (105). The optical rotation angle (302) of magneto-optical crystal module one (103), magneto-optical crystal module two (104), magneto-optical crystal module three (106), and magneto-optical crystal module four (107) is defined as positive counterclockwise and negative clockwise. Module 1 (103), Module 2 (104), Module 3 (106), and Module 4 (107) are composed of an optical rotation crystal (202) and a magnetic field loading device (201) inside each module. The magnetic field loading device (201) can apply saturated magnetic fields in both directions to the optical rotation crystal (202). It can independently control the magnetic field loading device (201) inside Module 1 (103), Module 2 (104), Module 3 (106), and Module 4 (107) to apply a saturated magnetic field to the optical rotation crystal (202) to control its optical rotation angle (302). The optical rotation angle (302) has two working states with optical rotation angle values ​​of φ or -φ. The optical rotation angle value φ is an angle between 0 degrees and 360 degrees and does not include 0 degrees, 45 degrees, 90 degrees, and 180 degrees.

2. A self-calibrated polarization state measurement method based on the trust region reflection method, wherein the light to be measured (401) enters a self-calibrated polarization state measurement device (402), the self-calibrated polarization state measurement device (402) is the self-calibrated polarization state measurement device as described in claim 1, the outgoing light of the self-calibrated polarization state measurement device (402) enters an optical power meter (403) and the optical power of the outgoing light is measured, and then the data is processed according to the following steps to complete the self-calibration and polarization state measurement of the self-calibrated polarization state measurement device: Step 1: By changing the combination of the optical rotation angle (302) of magneto-optical crystal module 1 (103), magneto-optical crystal module 2 (104), magneto-optical crystal module 3 (106), and magneto-optical crystal module 4 (107), and measuring the optical power of the emitted light using an optical power meter (403), it is found that each of the four magneto-optical crystal modules has two working states: φ or -φ. There are a total of 16 combinations of the optical rotation angle (302) of the four magneto-optical crystal modules. The optical power under each combination is measured and denoted as φ. The optical power measurement results are combined into an optical power matrix. T is the transpose symbol; Step 2, the measurement equation of the self-calibrated polarization state measurement device based on the trust region reflection method is as follows: , The matrix formed by the first row of the Mueller matrix of the self-calibrated polarization state measurement device (402) for the optical rotation angle (302) of magneto-optical crystal module one (103), magneto-optical crystal module two (104), magneto-optical crystal module three (106), and magneto-optical crystal module four (107) under 16 combinations. Each row vector is relative to the total optical rotation angle Ф1 of magneto-optical crystal module one (103) and magneto-optical crystal module two (104), the total optical rotation angle Ф2 of magneto-optical crystal module three (106) and magneto-optical crystal module four (107), the delay angle Γ of the quarter-wave plate (105), and the angle θ between the transmission polarization direction (301) of the analyzer (108) and the fast axis direction (303) of the quarter-wave plate (105). p related, The row vector expression for the i-th combination is: ， In the formula, Ф1 and Ф2 take values ​​of 2φ, 0, and -2φ, respectively. φ and θ... p Using Γ as parameters to be optimized, the measurement equations of the self-calibrated polarization state measurement device are iteratively solved using the trust region reflection method. The optimal solution, the optimization objective of the trust region reflection method is to make The norm reaches its minimum value. The Stokes vector characterizing the polarization state of the light to be measured; Step 3: Iteratively solve the measurement equations of the self-calibrated polarization state measurement device using the trust region reflection method. The optimal solutions φ and θ p Γ represents the calibration result of the self-calibrating polarization state measurement device (402). The Stokes vector characterizing the polarization state of the light under test can be expressed by the matrix representation of the least squares method. Calculations are performed to analyze the polarization state of the light under test.

3. The self-calibrated polarization state measurement method based on the trust region reflection method according to claim 2, characterized in that, In the iterative process of the trust region reflection method in step 2, the formula for calculating the objective function is as follows: , For the nth iteration, φ and θ p The matrix formed by the optimization results of Γ, Let n be the Stokes vector of the light to be measured in the nth iteration. The expression is .

4. The self-calibrated polarization state measurement method based on the trust region reflection method according to claim 2, characterized in that, When the light to be measured is known to be completely polarized, the optimization objective of the second step, the trust region reflection method, is to make... The norm reaches a minimum value, and S0, S1, S2 and S3 are elements in the Stokes vector that characterizes the photometric polarization state.

5. The self-calibrated polarization state measurement method based on the trust region reflection method according to claim 2, characterized in that, The step 2 trust region reflection method sets the parameters φ and θ to be optimized in iteration p The optimization result value range of φ, θ and Γ is the trust region radius, and the optimization parameters φ, θ p The optimization result value range of φ, θ and Γ is the tolerance range identified by the reference device manual or an estimated range according to experience, and is set to be greater than 20% to 30% of the tolerance range or the estimated range according to experience.

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