Chiral babinet parameters analytical system and method with common optical path and bimodal switching

Abstract

This invention discloses a common-path dual-mode switching chiral complex Pasteur parameter analysis system and method. The system includes: a monochromatic beam splitting module for generating a continuously tunable single-wavelength laser; a topologically balanced beam splitting module for splitting the single-wavelength laser emitted by the monochromatic beam splitting module into two parallel paths; a polarization modulation module for applying high-frequency phase delay modulation to the passing polarized light; a balanced detection module for converting the probe light and reference light into voltage signal outputs; a parameter analysis module for calculating and correcting the dual-mode chiral spectrum of the chiral material sample under test and performing complex Pasteur parameter analysis; and a mode switching module for switching between two states: alternating circular polarization modulation of mode A and alternating linear polarization modulation of mode B. This invention achieves a functional leap from spectral phenomenological measurement to constitutive analysis and establishes an inversion analysis protocol for directly mapping spectral signals to dimensionless complex Pasteur parameters.

Description

Technical Field

[0001] This invention relates to the field of precision measurement technology in chiral spectroscopy, and in particular to a chiral complex Pasteur parameter analysis system and method with common optical path dual-mode switching. Background Technology

[0002] The wavelength-dependent characteristics of circular birefringence and circular dichroism are called optical rotation dispersive spectroscopy (ORD) and circular dichroism (CD), respectively, and are theoretically proportional to the real part of the complex Pasteur parameter of the material. ) and imaginary part ( To address this, existing technologies have developed corresponding measurement methods for ORD and CD spectra. For a long time, academia and industry have primarily relied on independent polarimeters and circular dichroism spectrometers to obtain the chiral response spectra of chiral materials. Methods for measuring optical rotational dispersive spectra mainly include the zero-point method, the ratio method, and polarization measurement using a polarization camera. Methods for measuring CD spectra mainly include traditional mechanical waveplate rotation, phase modulation, and polarization modulation. These methods aim to improve measurement speed and reduce system complexity, while also enhancing measurement sensitivity. Among these methods, high-frequency modulation using a photoelastic modulator (PEM) or electro-optic modulator (EOM) combined with phase-locked synchronous detection is the mainstream trend for high-precision detection. A high-sensitivity circular dichroism measurement device (CN 118655091 B) based on a dual-arm balanced optical path pushes the chiral detection architecture from a single optical path to precise balanced differential detection, achieving extremely high measurement sensitivity in circular dichroism spectroscopy while maximally suppressing common-mode noise. Although such techniques provide a good solution for obtaining spectral data of chiral materials, existing chiral characterization techniques mostly focus on discrete phenomenological measurements of chiral spectra, which are limited to the acquisition of single physical quantities and lack a systematic solution for integrated analysis of complex Pasteur parameters of chiral materials from the perspective of constitutive and intrinsic properties.

[0003] Achieving a leap from macroscopic phenomenological parameters to decoupled analytical methods for complex constitutive parameters is a core challenge currently facing precision chiral spectroscopy. First, the asymmetric absence of the constitutive dimension limits a comprehensive reconstruction of the essence of chiral materials. Existing techniques largely focus on measuring individual chiral spectral information (providing a single CD or ORD spectrum measurement), resulting in a disconnect between the real and imaginary spectra in both time and space, making it difficult to meet the data completeness requirements of the analytical equations for complex constitutive parameters. Second, the existence of intrinsic coupling effects of complex Pasteur parameters in chiral materials leads to nonlinear modulation of the spectrum. Rigorous derivation proves that the circular dichroism absorption of chiral materials (… This will induce an elliptic shift in linearly polarized light after transmission through the material, causing the optical rotation dispersion corresponding to circular birefringence ( The nonlinear modulation is particularly pronounced near the resonant absorption band of the material, requiring correction of the true ORD spectrum of the chiral material by combining it with the CD spectrum. Finally, current technology lacks a direct mapping system from the original spectrum to the constitutive parameters of the chiral material. Since most instruments still operate at the level of spectral phenomenological indices in degrees, a systematic analytical system and method for the complex Pasteur parameters of chiral constitutive parameters are lacking. Summary of the Invention

[0004] The purpose of this invention is to provide a chiral complex Pasteur parameter analysis system and method with common optical path dual-mode switching, which realizes the functional leap from spectral phenomenological measurement to constitutive analysis and establishes an inversion analysis protocol for directly mapping spectral signals to dimensionless complex Pasteur parameters.

[0005] To achieve the above objectives, the present invention provides the following solution: A chiral complex Pasteur parameter analysis system for common-path dual-mode switching includes, in sequence: The monochromatic beam splitting module, including a broadband light source and a monochromator, is used to generate single-wavelength lasers with continuously tunable wavelengths; after being emitted by the broadband light source, the laser is selected as a single-wavelength laser by the monochromator. The topology balanced beam splitter module is used to split the single-wavelength laser emitted by the monochromatic beam splitter module into two parallel paths: one is a probe beam and the other is a reference beam. The probe beam and the reference beam have the same power and noise level. The polarization modulation module is used to apply high-frequency phase delay modulation to the passing polarized light; The test sample module includes a sample chamber for holding the chiral material sample to be tested; The balanced detection module is used to convert the probe light and reference light into voltage signal outputs; The parameter analysis module is used to calculate the corrected dual-modal chiral spectrum of the chiral material sample and perform complex Pasteur parameter analysis; it also includes: The mode switching module, connected to the polarization modulation module, is used to achieve alternating circular polarization modulation and alternating linear polarization modulation by switching between mode A and mode B.

[0006] Preferably, the topological balanced beam splitting module includes a first polarizer, a first unpolarized beam splitting prism, a second unpolarized beam splitting prism, and a third unpolarized beam splitting prism. During operation, a single-wavelength laser is set to horizontal linear polarization by the first polarizer, transmitted through the first unpolarized beam splitting prism, reflected by the second unpolarized beam splitting prism to form a probe beam, and reflected by the first unpolarized beam splitting prism and transmitted through the third unpolarized beam splitting prism to form a reference beam.

[0007] Preferably, the polarization modulation module includes a second polarizer and a high-frequency phase modulator arranged sequentially; wherein the polarization axis of the second polarizer is horizontally polarized; the phase modulation of the high-frequency phase modulator is wavelength-dependent, and the modulation frequency and mode are controllable.

[0008] Preferably, the balance detection module includes a photoelectric balance detector, a right-angle prism, a lock-in amplifier, and a data acquisition card; wherein, the photoelectric balance detector has two identical light receivers, which respectively receive the detection light passing through the sample and the reference light used for noise balance, and the differential voltage and DC voltage output by the photoelectric balance detector are measured by the lock-in amplifier and the data acquisition card respectively using AC differential and DC averaging; the right-angle prism is used to reflect the reference light to the corresponding light receiver, so that it enters the photoelectric balance detector.

[0009] Preferably, the mode switching module includes a first analyzer and a polarization state switching unit, including mode A and mode B; wherein, when the polarization state switching unit is in mode A, it drives the first analyzer to move out of the optical path, and simultaneously drives the polarization modulation module to perform circular polarization alternating modulation, and the probe optical path to perform circular dichroism spectroscopy measurement; when the polarization state switching unit is in mode B, it drives the first analyzer to move into the optical path, and simultaneously drives the polarization modulation module to perform linear polarization alternating modulation, and the probe optical path to perform original optical rotation dispersive spectrum measurement.

[0010] Preferably, the parameter analysis module includes a calculation and analysis unit for performing the calculation and correction of the dual-modal spectrum, as well as the high-precision analysis of the complex Pasteur parameters.

[0011] A method for analyzing chiral complex Pasteur parameters in co-optical path dual-mode switching, applied to any of the above-mentioned chiral complex Pasteur parameter analysis systems in co-optical path dual-mode switching, includes the following steps: S1. A single-wavelength laser with continuously adjustable wavelength is generated based on a monochromatic beam splitter module. The single-wavelength laser emitted by the monochromatic beam splitter module is split into two parallel paths through a topological balanced beam splitter module. One path is a probe light and the other path is a reference light. S2. The probe light is modulated using a mode switching module and a polarization modulation module; the modulated probe light and reference light are converted into voltage signals by a balanced detection module. Based on the output voltage signals, the dual-mode chiral spectrum of the chiral material sample under test is calculated and corrected using a parameter analysis module, and complex Pasteur parameter analysis is performed. Specifically, this includes: S201. Based on the modulation of the mode switching module and the polarization modulation module, the circular dichroism spectral signal in the same band and the uncorrected optical rotation dispersion spectrum are obtained. S202. The optical rotation dispersion spectrum is corrected using a nonlinear coupling model derived from the Jones matrix, and the optical rotation dispersion angle is calculated. S203. Based on the constitutive relation of chiral materials and the characteristic equation of plane wave propagation, a linear mapping relationship between complex Pasteur parameters and complex optical rotation angles is established to achieve direct inversion of the constitutive parameters of chiral materials.

[0012] Preferably, in S201, the formula for the circular dichroism spectral signal in the same band is as follows:

[0013] The uncorrected formula for optical rotation dispersive spectroscopy is as follows:

[0014] Where A is the circular dichroism conversion coefficient. This is the ratio of the differential voltage to the DC voltage. The phase function is used to determine the sign of the differential voltage, and B is the optical rotation dispersion conversion coefficient. and These represent the response voltages of left-handed and right-handed circularly polarized light after passing through the sample during circular dichroism spectroscopy measurements. and These represent the response voltages of horizontally and vertically linearly polarized light after passing through the sample during optical rotation dispersive spectroscopy measurements.

[0015] Preferably, in S202, the optical rotation dispersion spectrum is corrected using a nonlinear coupling model derived from the Jones matrix, and the optical rotation dispersion angle is calculated using the following formula:

[0016] in, It is the optical dispersion angle. This is the uncorrected optical rotation dispersion spectrum. It is a circular dichroic spectral signal.

[0017] Preferably, in S203, the complex Pasteur parameters are calculated as follows:

[0018] If the chiral material to be tested is a liquid solution, the effective optical path is The complex Pasteur parameters are then calculated using the following equation:

[0019] If the chiral material to be tested is a solid material, the material thickness is... The complex Pasteur parameters are then calculated using the following equation:

[0020] in, Here are the complex Pasteur parameters, where i is the imaginary unit. λ is the wavelength.

[0021] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects: This invention completes the physical dimension of precise chiral spectral measurement through a common-path dual-mode switching scheme, achieving full reconstruction of constitutive parameters. It overcomes the shortcomings of existing technologies, such as the separate measurement architecture of CD and ORD spectra and the lack of chiral response dimension, allowing complex Pasteur parameters to be obtained in a single system. For the first time, a decoupling correction model based on complex constitutive derivation is introduced, effectively eliminating the intrinsic nonlinear modulation interference of chiral materials and correcting the systematically small real part of the constitutive parameters resolved near the resonant absorption band. It achieves a functional leap from spectral phenomenological measurement to constitutive analysis, establishes an inversion analytical protocol for directly mapping spectral signals to dimensionless complex Pasteur parameters, and provides the first complex Pasteur parameter analysis system for chiral materials. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the chiral complex Pasteur parameter analysis system with co-optical path dual-mode switching according to the present invention; Figure 2 This is a block diagram of the structural modules of the chiral complex Pasteur parameter analysis system with co-optical path dual-mode switching according to the present invention; Figure 3 This is a schematic diagram illustrating the movable elements and polarization modulation state of the common optical path dual-mode switching module of the present invention. Wherein, (a) is a schematic diagram of the switching principle of mode A, and (b) is a schematic diagram of the switching principle of mode B; Figure 4 This is a flowchart illustrating the steps of the chiral complex Pasteur parameter analysis method in this invention. Figure 5 This is a schematic diagram illustrating the ORD spectrum correction achieved using the CD spectrum based on the decoupling correction equation and its correction effect in an embodiment of the present invention. Among them, (a) is the CD spectrum measured in a wide spectral range of 400-800 nm. (b) shows the measured ORD spectrum to be corrected. and the corrected true ORD spectrum The difference; Figure 6 This is a schematic diagram illustrating the results of the integrated and complete analysis of complex Pasteur parameters of chiral materials in this invention; Among them, 1-broadband light source, 2-monochromator, 3-first polarizer, 4-first unpolarized beam splitter, 5-second unpolarized beam splitter, 6-second polarizer, 7-high frequency phase modulator, 8-sample chamber, 9-first analyzer, 10-photoelectric balance detector, 11-third unpolarized beam splitter, 12-third polarizer, 13-polarization state switching unit, 14-right angle prism, 15-lock-in amplifier, 16-data acquisition card, 17-calculation and analysis unit. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Example 1 like Figure 1 and Figure 2 As shown, a chiral complex Pasteur parameter analysis system for common-path dual-mode switching includes the following components arranged sequentially: The monochromatic beam splitting module, including a broadband light source and a monochromator, is used to generate single-wavelength lasers with continuously tunable wavelengths; after being emitted by the broadband light source, the laser is selected as a single-wavelength laser by the monochromator. The topology balanced beam splitter module is used to split the single-wavelength laser emitted by the monochromatic beam splitter module into two parallel paths: one is a probe beam and the other is a reference beam. The probe beam and the reference beam have the same power and noise level. The polarization modulation module is used to apply high-frequency phase delay modulation to the passing polarized light; The test sample module includes a sample chamber for holding the chiral material sample to be tested; The balanced detection module is used to convert the probe light and reference light into voltage signal outputs; The parameter analysis module is used to calculate the corrected dual-modal chiral spectrum of the chiral material sample and perform complex Pasteur parameter analysis; it also includes: The mode switching module, connected to the polarization modulation module, is used to achieve alternating circular polarization modulation and alternating linear polarization modulation by switching between mode A and mode B.

[0027] This embodiment provides, for example Figure 1 and Figure 2The proposed system for analyzing chiral complex Pasteur parameters in a common-path dual-mode switching configuration is as follows: By constructing a common optical path detection system for chiral circular dichroism and optical rotation dispersive spectroscopy, and utilizing a mode conversion module to achieve polarization control conversion, a high-precision analytical system for resolving complex Pasteur parameters of chiral materials was constructed. Furthermore, by combining a decoupling correction equation to correct the optical rotation dispersive spectrum affected by coupling, parameter inversion was achieved.

[0028] Based on this concept, such as Figure 2 As shown, the system in this embodiment includes the following modules: a monochromatic spectral splitting module, a topological equilibrium spectral splitting module, a polarization modulation module, a mode switching module, a sample under test module, an equilibrium detection module, and a parameter analysis module. Specifically... Figure 1 As shown: Monochromatic Spectrometer Module: This module includes a broadband light source 1 and a monochromator 2. The broadband light source can provide broadband laser light required for the measurement wavelength range. After the laser light is emitted by the broadband light source 1, it is selected as a single wavelength laser light by the monochromator 2.

[0029] Topologically Balanced Beam Splitting Module: This module includes a first polarizer 3, a first unpolarized beam splitter prism 4, a second unpolarized beam splitter prism 5, and a third unpolarized beam splitter prism 11. The first polarizer 3 has a high extinction ratio, and its polarization axis is set to horizontal polarization (H). The first, second, and third unpolarized beam splitters are placed sequentially and strictly according to the positions shown in the diagram to form a topologically symmetrical structure, with parallel optical axes and completely consistent optical performance. Specifically, during operation, a single-wavelength laser is set to horizontal linear polarization by the first polarizer 3. After being transmitted through the first unpolarized beam splitter prism 4 and reflected by the second unpolarized beam splitter prism 5, it forms the probe light. After being reflected by the first unpolarized beam splitter prism 4 and transmitted through the third unpolarized beam splitter prism 11, it forms the reference light. The probe light and reference light are formed by the horizontal linear polarization light passing through one transmission and one reflection of the optically consistent unpolarized beam splitters, respectively, and are optically completely balanced.

[0030] The polarization modulation module includes a second polarizer 6 and a high-frequency phase modulator 7. The second polarizer 6 has a horizontal polarization axis, which aims to further improve the purity of horizontal polarization. The high-frequency phase modulator 7 has a wavelength-dependent phase modulation, and the modulation frequency and mode are controllable.

[0031] The test sample module includes a sample chamber 8 for holding the chiral material sample to be tested, the sample having complex Pasteur parameters (…). Chiral material samples can be either solutions or solids.

[0032] The mode switching module includes a polarization state switching unit 13 and a first analyzer 9 that can be moved in or out of the optical path. The polarization state switching unit has two modulation states, mode A and mode B. The polarization axis of the first analyzer 9 is set at 45° to the horizontal direction. A schematic diagram of the mode switching principle is shown below. Figure 3 As shown in (a)-(b), specifically, when the polarization state switching unit is in mode A, it drives the first analyzer 9 to move out of the optical path, and at the same time drives the polarization modulation module 7 to perform circular polarization alternation modulation (L / R), and the probe optical path performs circular dichroism spectroscopy measurement; when the polarization state switching unit is in mode B, it drives the first analyzer 9 to move into the optical path, and at the same time drives the polarization modulation module 7 to perform linear polarization alternation modulation (H / V), and the probe optical path performs original optical rotation dispersive spectrum measurement.

[0033] The balanced detection module includes a photoelectric balanced detector 10, a right-angle prism 14, a lock-in amplifier 15, and a data acquisition card 16. The photoelectric balanced detector 10 has two identical photoreceivers, one for receiving the probe light passing through the sample and the other for receiving reference light used for noise balancing. Its output differential voltage is measured by the lock-in amplifier 15 and the data acquisition card using AC differential and DC averaging measurements, respectively. DC voltage And the determination of the positive and negative values ​​of differential voltages is based on phase. The right-angle prism serves to reflect the reference beam into the photoelectric balanced detector. The purpose of using it is that since the right-angle prism is not coated with an optical thin film, it will not introduce additional dispersion and disrupt the balance of the topological balanced optical path.

[0034] The parameter analysis module includes a calculation and analysis unit 17, which performs the calculation and correction of dual-modal spectra, as well as high-precision analysis of complex Pasteur parameters.

[0035] It also includes the third polarizer 12 located in Figure 1 The position shown in the reference optical path is used for precise fine-tuning to achieve a precise balance between the reference optical path and the probe optical path.

[0036] This invention also provides a chiral complex Pasteur parameter analysis method for common-path dual-mode switching, applied to a chiral complex Pasteur parameter analysis system for common-path dual-mode switching as described above, comprising the following steps: S1. A single-wavelength laser with continuously adjustable wavelength is generated based on a monochromatic beam splitter module. The single-wavelength laser emitted by the monochromatic beam splitter module is split into two parallel paths through a topological balanced beam splitter module. One path is a probe light and the other path is a reference light. S2. The probe light is modulated using a mode switching module and a polarization modulation module; the modulated probe light and reference light are converted into voltage signals by a balanced detection module. Based on the output voltage signals, the dual-mode chiral spectrum of the chiral material sample under test is calculated and corrected using a parameter analysis module, and complex Pasteur parameter analysis is performed. Specifically, this includes: S201. Based on the modulation of the mode switching module and the polarization modulation module, the circular dichroism spectral signal in the same band and the uncorrected optical rotation dispersion spectrum are obtained. S202. The optical rotation dispersion spectrum is corrected using a nonlinear coupling model derived from the Jones matrix, and the optical rotation dispersion angle is calculated. S203. Based on the constitutive relation of chiral materials and the characteristic equation of plane wave propagation, a linear mapping relationship between complex Pasteur parameters and complex optical rotation angles is established to achieve direct inversion of the constitutive parameters of chiral materials.

[0037] This embodiment provides, for example Figure 4 The chiral complex Pasteur parameter analysis method shown below has the following steps: The first step is to perform mode A measurement, i.e., circular dichroism spectroscopy measurement. The voltage signal output from the balanced detection module is fed into the parameter analysis module for spectral calculation to obtain an accurate CD spectrum. Its formula is: Where A is the circular dichroism conversion coefficient. The ratio of differential voltage to DC voltage, a shared structural principle in the common optical path system, ensures the system's high sensitivity. The phase function is used to determine the sign of the differential voltage, and its specific form is as follows: The value can be 1 or -1.

[0038] The second step involves performing mode B measurement, i.e., optical rotation dispersive spectroscopy measurement. The voltage signal output from the balanced detection module is fed into the parameter analysis module for spectral calculation to obtain the ORD spectrum to be corrected. Its formula is: Where B is the optical rotation dispersion conversion coefficient, and the other symbols have the same meaning as above.

[0039] The third step involves introducing a decoupling correction model to correct nonlinear coupling. Specifically, this is achieved through the formula... Calculate and obtain the corrected true ORD spectrum .like Figure 5 As shown, Figure 5 Figure (a) shows the spectral results of the above three steps within a wide spectral range of 400-800 nm. The three curves represent the measured CD spectra. The measured ORD spectrum to be corrected and the corrected true ORD spectrum ; Figure 5(b) shows the measured ORD spectrum to be corrected. and the corrected true ORD spectrum The difference in the results effectively reflects the necessity of nonlinear correction in this invention, providing a data foundation for subsequent high-precision parameter inversion. This result is demonstrative.

[0040] The fourth step involves analyzing the complex Pasteur parameters and establishing dimensionless complex Pasteur parameters. With complex optical rotation angle The linear mapping relationship and the built-in inversion algorithm, among which The true optical rotation dispersion spectrum is obtained after nonlinear decoupling correction. The circular dichroism chromatograms obtained are in radians. Considering the state of the sample: If the chiral material to be tested is a liquid solution, the effective optical path is The complex Pasteur parameters can then be analyzed using the following equation: ; If the chiral material to be tested is a solid material, the material thickness is... The complex Pasteur parameters can then be analyzed using the following equation: .

[0041] In this embodiment, Figure 6 The spectrum results of high-precision inversion of complex Pasteur parameters for an example chiral material are shown.

[0042] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0043] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A chiral complex Pasteur parameter analysis system for common-path dual-mode switching, characterized in that, Including the following settings in sequence: A monochromatic beam splitting module, including a broadband light source and a monochromator, is used to generate a single-wavelength laser with continuously tunable wavelength; after the laser is emitted by the broadband light source, it is selected as a single-wavelength laser by the monochromator. A topological balanced beam splitter module is used to split a single-wavelength laser emitted by a monochromatic beam splitter module into two parallel paths: one is a probe beam and the other is a reference beam, and the probe beam and the reference beam have the same power and noise level. The polarization modulation module is used to apply high-frequency phase delay modulation to the passing polarized light; The test sample module includes a sample chamber for holding the chiral material sample to be tested; The balanced detection module is used to convert the probe light and reference light into voltage signal outputs; The parameter analysis module is used to calculate and correct the dual-modal chiral spectrum of the chiral material sample to be tested and perform complex Pasteur parameter analysis. It also includes a mode switching module, connected to the polarization modulation module, used to achieve alternating circular polarization modulation and alternating linear polarization modulation by switching mode A and mode B.

2. A co-linear dual-mode switching chiral compound babinet parameter resolving system according to claim 1, characterized in that, The topological balanced beam splitting module includes a first polarizer, a first unpolarized beam splitting prism, a second unpolarized beam splitting prism, and a third unpolarized beam splitting prism. During operation, the single-wavelength laser is set to horizontal linear polarization by the first polarizer, transmitted through the first unpolarized beam splitting prism, reflected by the second unpolarized beam splitting prism to form a probe beam, and reflected by the first unpolarized beam splitting prism and transmitted through the third unpolarized beam splitting prism to form a reference beam.

3. The in-line dual-mode switching chiral biaxial parameter resolving system according to claim 1, characterized in that, The polarization modulation module includes a second polarizer and a high-frequency phase modulator arranged in sequence; wherein the polarization axis of the second polarizer is horizontally polarized; the phase modulation of the high-frequency phase modulator is wavelength dependent, and the modulation frequency and mode are controllable.

4. The chiral complex Pasteur parameter analysis system for common-path dual-mode switching according to claim 1, characterized in that, The balance detection module includes a photoelectric balance detector, a right-angle prism, a lock-in amplifier, and a data acquisition card. The photoelectric balance detector has two identical light receivers, which respectively receive the probe light passing through the sample and the reference light used for noise balance. The differential voltage and DC voltage output by the photoelectric balance detector are measured by the lock-in amplifier and the data acquisition card, respectively, using AC differential and DC averaging. The right-angle prism is used to reflect the reference light to the corresponding light receiver, allowing it to enter the photoelectric balance detector.

5. The in-line dual-mode switching chiral biaxial parameter resolving system according to claim 1, wherein, The mode switching module includes a first analyzer and a polarization state switching unit, used to switch between mode A and mode B. When the polarization state switching unit is in mode A, it drives the first analyzer to move out of the optical path and simultaneously drives the polarization modulation module to perform circular polarization alternating modulation, and the probe optical path to perform circular dichroism spectroscopy measurement. When the polarization state switching unit is in mode B, it drives the first analyzer to move into the optical path and simultaneously drives the polarization modulation module to perform linear polarization alternating modulation, and the probe optical path to perform original optical rotation dispersive spectrum measurement.

6. The chiral complex Pasteur parameter analysis system for common-path dual-mode switching according to claim 1, characterized in that, The parameter analysis module includes a calculation and analysis unit for performing the calculation and correction of dual-modal spectra, as well as high-precision analysis of complex Pasteur parameters.

7. A method for analyzing chiral complex Pasteur parameters in co-optical path dual-mode switching, applied to the chiral complex Pasteur parameter analysis system for co-optical path dual-mode switching as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. A single-wavelength laser with continuously adjustable wavelength is generated based on a monochromatic beam splitter module. The single-wavelength laser emitted by the monochromatic beam splitter module is split into two parallel paths through a topological balanced beam splitter module. One path is a probe light and the other path is a reference light. S2. The probe light is modulated using a mode switching module and a polarization modulation module; the modulated probe light and reference light are converted into voltage signals by a balanced detection module. Based on the output voltage signals, the dual-mode chiral spectrum of the chiral material sample under test is calculated and corrected using a parameter analysis module, and complex Pasteur parameter analysis is performed. Specifically, this includes: S201. Based on the modulation of the mode switching module and the polarization modulation module, the circular dichroism spectral signal in the same band and the uncorrected optical rotation dispersion spectrum are obtained. S202. The optical rotation dispersion spectrum is corrected using a nonlinear coupling model derived from the Jones matrix, and the optical rotation dispersion angle is calculated. S203. Based on the constitutive relation of chiral materials and the characteristic equation of plane wave propagation, a linear mapping relationship between complex Pasteur parameters and complex optical rotation angles is established to achieve direct inversion of the constitutive parameters of chiral materials.

8. The chiral complex Pasteur parameter analysis method for common-path dual-mode switching according to claim 7, characterized in that, In S201, the formula for the circular dichroism spectral signal in the same band is as follows: The uncorrected formula for optical rotation dispersive spectroscopy is as follows: Where A is the circular dichroism conversion coefficient. This is the ratio of the differential voltage to the DC voltage. The phase function is used to determine the sign of the differential voltage, and B is the optical rotation dispersion conversion coefficient. and These represent the response voltages of left-handed and right-handed circularly polarized light after passing through the sample during circular dichroism spectroscopy measurements. and These represent the response voltages of horizontally and vertically linearly polarized light after passing through the sample during optical rotation dispersive spectroscopy measurements.

9. The chiral complex Pasteur parameter analysis method for common-path dual-mode switching according to claim 8, characterized in that, In step S202, the optical rotation dispersion spectrum is corrected using a nonlinear coupling model derived from the Jones matrix, and the optical rotation dispersion angle is calculated using the following formula: in, It is the optical dispersion angle. This is the uncorrected optical rotation dispersion spectrum. It is a circular dichroic spectral signal.

10. The chiral complex Pasteur parameter analysis method for common-path dual-mode switching according to claim 9, wherein in S203, the complex Pasteur parameter is calculated as follows: If the chiral material to be tested is a liquid solution, the effective optical path is The complex Pasteur parameters are then calculated using the following equation: If the chiral material to be tested is a solid material, the material thickness is... The complex Pasteur parameters are then calculated using the following equation: in, Here are the complex Pasteur parameters, where i is the imaginary unit. λ is the wavelength.

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