Method for detecting raman spectra and device therefor

Abstract

The application relates to the technical field of spatial offset Raman spectroscopy, and discloses a method for detecting Raman spectroscopy and a device thereof. The method comprises the following steps: arranging two or more illumination areas on a sample, which are respectively illumination areas alpha 1, alpha 2, alpha 3,..., and alpha m; the spatial offset of the illumination area alpha 1 relative to a signal collection area beta is delta 1, the spatial offset of the illumination area alpha 2 is delta 2, the spatial offset of the illumination area alpha 3 is delta 3, and the spatial offset of the illumination area alpha m is delta m; the spatial offsets of delta 1, delta 2, delta 3 and delta m are preset parameters; laser irradiates the m illumination areas simultaneously; the laser power ratio between the m illumination areas is adjusted, and the mixed Raman spectrum of the signal collection area is collected multiple times; and the mixed Raman spectrum is demixed to obtain the pure Raman spectrum excited by the m illumination areas. According to the application, efficient detection of the spatial offset Raman spectrum can be realized, the finally obtained pure Raman spectrum signal is high in purity, and the detection is stable and efficient.

Description

Technical Field

[0001] This application relates to the field of spatially shifted Raman spectroscopy, specifically a method and apparatus for detecting Raman spectra. Background Technology

[0002] Spatial migration Raman spectroscopy (SORS), an important branch of Raman spectroscopy analysis, can detect information at different depths of a sample by adjusting the relative spatial offset between the excitation point and the signal collection point. It has irreplaceable application value in non-invasive medical diagnosis (such as detection of deep skin lesions) and security inspection for contraband identification (such as detection through packaging materials). Its core principle is that the Raman scattering signals generated by substances at different depths under laser excitation exhibit specific distribution patterns due to differences in the offset. By analyzing the Raman spectra corresponding to different offsets, the layered composition information of the sample can be retrieved.

[0003] In existing SORS technology, the signal acquisition methods for spatial offset are mainly divided into three categories: first, fixed probe technology, which uses mechanical structures to fix the relative positions of the excitation end and the collection end to obtain a Raman signal with a single fixed offset; second, adjustable displacement technology, which uses mechanical movement to switch the offset to achieve signal acquisition with different offsets; and third, non-contact spatial scanning technology, such as dynamically selecting the signal collection area based on a spatial light modulator (SLM) to adjust the offset.

[0004] However, the aforementioned existing technologies share a common core limitation: Raman scattering signals with different offsets are acquired separately, and the spectral data are independent of each other, lacking a mathematical correlation for simultaneous solution. Specifically, this manifests as follows:

[0005] The spectrum acquired individually contains only the linear superposition of signal and noise at the corresponding offset. Since each noise is independent and unknown, it is impossible to suppress the noise through correlation calculation between the noises.

[0006] When resolving the target pure signal from a single set of independent spectra, since both the signal component and the noise component are unknowns, there is a mathematical underdeterminacy problem, that is, the number of unknown parameters in the observation equation is greater than the number of equations, making it impossible to uniquely solve the pure signal.

[0007] When performing simultaneous analysis on the multilayer spectral signals of the sample and the corresponding weighting coefficients, the uncertainty is further aggravated because both are unknowns, making it difficult to obtain accurate layered pure spectra.

[0008] Therefore, existing SORS technology cannot remove noise and unmix the target spectrum through collaborative analysis of multiple offset signals, which limits its accuracy in high-noise environments or weak-signal sample detection. There is an urgent need for a technical solution that can establish mathematical correlations between multiple offset signals and achieve noise suppression and pure spectral unmixing through collaborative analysis. Summary of the Invention

[0009] The purpose of this application is to provide a method and apparatus for detecting Raman spectra, so as to solve the technical problems mentioned in the background art.

[0010] To achieve the above objectives, this application discloses the following technical solutions:

[0011] In a first aspect, this application discloses a method for detecting Raman spectra, the method comprising the following steps:

[0012] Two or more irradiation areas are set on the sample, namely irradiation areas α1, α2, α3, ..., αm. The spatial offset of irradiation area α1 relative to signal collection area β is δ1, the spatial offset of irradiation area α2 is δ2, the spatial offset of irradiation area α3 is δ3, ..., the spatial offset of irradiation area αm is δm, and δ1, δ2, δ3, ..., δm are preset parameters.

[0013] The laser simultaneously irradiates m irradiation areas;

[0014] Adjust the ratio of laser power applied to the m irradiation areas and repeatedly collect the mixed Raman spectrum of the signal collection area;

[0015] The mixed Raman spectra are demixed to obtain pure Raman spectra excited by m irradiation regions.

[0016] Preferably, the spatial offset is determined in the following manner:

[0017] Laser beam splitting is achieved by using a beam splitter, and different beams form different irradiation areas on the sample surface.

[0018] Preferably, the adjustment of the laser power ratio among the m irradiation areas includes the following steps:

[0019] The laser ratio is adjusted by a proportional control unit; wherein the proportional control unit uses a proportional adjustment method including polarization adjustment, intensity adjustment or duty cycle adjustment.

[0020] Preferably, the expression for the mixed Raman spectrum is a. 1n ×Signalα1+a 2n ×Signalα² + … + a mn ×Signalαm+Noisen=Spectrumβn, where, a mn Let αm be the laser scaling factor of the irradiated region αm during the nth acquisition, Signalαm be the Raman scattering information excited in the irradiated region αm, Noisen be the noise, and Spectrumβn be the mixed Raman spectrum of the nth acquisition.

[0021] Preferably, the demixing process of the mixed Raman spectrum to obtain pure Raman spectra excited in m irradiation regions includes the following steps:

[0022] Noise was removed using spectral data processing methods to obtain a 1n ×Signalα1+a 2n ×Signalα² + … + a mn ×Signalαm=Spectrumβn-Noisen, and analyze Signalα1, Signalα2……and Signalαm.

[0023] Secondly, this application discloses an apparatus for detecting Raman spectra, the apparatus comprising:

[0024] A laser source is used to provide the laser beam for illumination.

[0025] The irradiation modulation module includes an offset preset component and a ratio control unit; the offset preset component is used to preset spatial offsets δ1, δ2...δm relative to the signal collection area β on the sample, wherein the position of the spatial offset δm is defined as the irradiation area αm; the ratio control unit is used to adjust the laser ratio between the m irradiation areas.

[0026] The detection module is used to acquire the mixed Raman spectrum of the signal collection region;

[0027] The processing module is used to process and output the mixed Raman spectrum.

[0028] Preferably, the offset preset component includes a beam splitting element, which splits the laser beam to form irradiation areas α1, α2, ... and αm on the sample surface.

[0029] Preferably, the proportional control unit includes a polarizer, a waveplate, a filter, a beam splitter, or a laser duty cycle adjustment unit.

[0030] Preferably, the device further includes an optical component; the optical component is disposed between at least one of the following: a laser and an irradiation modulation module, a sample and an irradiation modulation module, and a sample and a detection module; the optical component is used to guide the laser to the sample and form a preset spatial offset.

[0031] Preferably, the processing module demixes the mixed Raman spectra using a preset spectral data processing method.

[0032] Beneficial effects: The method and apparatus for detecting Raman spectra in this application simultaneously irradiate a preset offset, enabling the acquired mixed spectrum to contain the coupling relationship of multiple signals. Multiple sets of mixed spectra are then obtained by adjusting the laser ratio. Based on demixing processing, the pure Raman spectra excited in all irradiated areas are obtained, achieving the ability to perform synergistic analysis of multiple spectra. Simultaneously, by setting the offset and fixing the optical path, the laser ratio can be adjusted only through optical means such as a ratio control unit, completing the acquisition of multiple sets of data without mechanical movement. This avoids interference from mechanical errors on the signal, significantly shortens the detection time, and improves system stability and detection efficiency. Furthermore, by solving the problems of noise removal and pure signal demixing, this application demonstrates significant advantages in fields with stringent signal quality requirements, meeting the needs of practical applications for low-noise, high-fidelity spectra. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 A flowchart illustrating a method for detecting Raman spectra provided in an embodiment of this application;

[0035] Figure 2 This is a schematic diagram of the device for detecting Raman spectra provided in an embodiment of this application. Detailed Implementation

[0036] The technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0037] In this document, the term "comprising" is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0038] This embodiment discloses, in a first aspect, a method as follows: Figure 1The method shown is designed to achieve efficient detection of spatially shifted Raman spectra through birefringence polarization modulation technology. It solves the problems of independent spectral acquisition, difficulty in noise removal, and unmixing and underdeterminacy in existing technologies, and is applicable to scenarios such as non-invasive medical diagnosis and security inspection of contraband.

[0039] Specifically, the method for detecting Raman spectra in this embodiment includes the following steps:

[0040] Step 1 - Set two or more irradiation zones on the sample, named irradiation zones α1, α2, α3, ..., αm. The spatial offset of irradiation zone α1 relative to the signal collection zone β is δ1, the spatial offset of irradiation zone α2 is δ2, the spatial offset of irradiation zone α3 is δ3, ..., the spatial offset of irradiation zone αm is δm, and δ1, δ2, δ3, ..., δm are preset parameters. It should be understood that this step determines the offset before determining the corresponding irradiation zone. Specifically:

[0041] First, a preset spatial offset is established. Then, a laser beam is split using a beam-splitting element, allowing different beams to form preset irradiation areas on the sample surface. A beam-splitting element utilizes the physical properties of light, such as reflection, refraction, diffraction, and polarization, to split a single beam of light into two or more beams. For example, elements that utilize birefringence to create differences in the refraction of different light (including but not limited to crystals such as quartz, magnesium fluoride, and calcite) are used. This embodiment uses magnesium fluoride (MgF2) as an example. Magnesium fluoride (MgF2) has a birefringence Δn = 0.005 (o-ray refractive index n0 = 1.378, e-ray refractive index n...). e =1.383). Set the irradiation area α1 (δ1 = 50 μm) and the irradiation area α2 (δ2 = 100 μm), and calculate the crystal thickness of magnesium fluoride according to the laws of geometric optics.

[0042] Taking the formation of two irradiation zones as an example, the basic characteristic of magnesium fluoride is that it has different refractive indices for different types of light (ordinary ray, o-ray and extraordinary ray, e-ray): the refractive index of o-ray is n0, and the refractive index of e-ray is n... e The birefringence Δn is defined as the difference between the two (Δn = |n|). e -n0|). When a laser beam is incident on magnesium fluoride, the o-ray and e-ray will produce different refraction angles due to their different refractive indices. After propagation through the crystal, the two beams will form a lateral separation in the irradiated area on the sample surface. This separation distance is the spatial offset δ (δ1 corresponds to the o-ray irradiated area α1, and δ2 corresponds to the e-ray irradiated area α2). The specific calculation process is based on the following principle:

[0043] Optical path difference and refraction angle difference: After the laser enters magnesium fluoride, the o-ray and e-ray propagate along different paths, and their refraction angles follow the law of refraction (n1·sinθ1=n2·sinθ2, where, Where n is the refractive index of the incident medium, θ1 is the angle of incidence, n2 is the refractive index of light in the crystal, and θ2 is the angle of refraction. Since n2 is different for o-ray and e-ray (n0 and n...),... e The angles of refraction differ between the two (Δθ=|θ e -θ0|);

[0044] Lateral offset calculation: Considering the crystal thickness d of magnesium fluoride, the lateral separation distance (i.e., spatial offset δ) of the two beams within the magnesium fluoride crystal can be derived geometrically: δ≈d·tan(Δθ). Since Δθ is determined by Δn and the incident angle, the final magnitude of δ is directly related to the birefringence Δn (which directly affects Δθ) and the crystal thickness (which affects the cumulative amount of lateral separation).

[0045] In short, by presetting the Δn (determined by the crystal material itself, such as the inherent parameters of MgF2, calcite, etc.) and thickness d of the beam splitting element, the spatial offsets δ1 and δ2 of the irradiation areas α1 and α2 formed by o-light and e-light on the sample can be accurately calculated, thus achieving precise presetting of the two irradiation areas.

[0046] Therefore, by deriving from the law of refraction, Δθ≈Δn·sinθ1 / n1 (θ1 is taken as 30°, n1 is the refractive index of air 1), we get Δθ≈0.005×0.5 / 1=0.0025rad;

[0047] Substituting δ≈d·tan(Δθ), we get d1≈δ1 / Δθ=50μm / 0.0025=20mm (corresponding to δ1), d2=40mm (corresponding to δ2). In practice, a MgF2 crystal with a crystal thickness of 20mm is selected, and the o-ray and e-ray are designed to form δ1 and δ2 respectively.

[0048] Step 2 - Simultaneously irradiate m irradiation areas with laser. Details are as follows:

[0049] The preferred center wavelengths for laser source output include, but are not limited to: 257±0.5nm, 261±0.5nm, 266±0.5nm, 320±0.5nm, 355±0.5nm, 360±0.5nm, 366±0.5nm, 405±0.5nm, 457±0.5nm, 473±0.5nm, 488±0.5nm, 514.5±0.5nm, 532±0.5nm, 561±0.5nm, 589±0.5nm, 633±0.5nm, 660±0.5nm, 671±0.5nm, 785±0.5nm, 808±0.5nm, 830±0.5nm, 980±0.5nm, and 1064±0.5nm. In this embodiment, a 532nm solid-state laser (50mW power) is used as the light source. The laser light is incident on the beam splitter after passing through the proportional control unit.

[0050] Step 3 - Adjust the laser power ratio among the m irradiation areas and repeatedly collect the mixed Raman spectrum of the signal collection area. The laser ratio is adjusted by a ratio control unit. In this embodiment, the ratio control unit can be any existing element that adjusts the light ratio by changing the polarization state, including but not limited to polarizers, waveplates, filters, beam splitters, or laser duty cycle adjustment units. Taking a polarizer as an example, the specific laser power ratio adjustment is as follows:

[0051] After passing through a polarizer, the laser light becomes linearly polarized and is then incident on a beam-splitting element. The ratio is adjusted to satisfy Malus's law. Malus's law states that when linearly polarized light passes through a polarizer, the intensity of the transmitted light is directly proportional to the intensity of the incident light and also proportional to the square of the cosine of the angle between the two polarization directions (the incident polarization direction and the polarization direction of the polarizer), i.e., I = I₀·cosθ. 2 α (where I is the transmitted light intensity, I0 is the incident light intensity, and α is the angle between the two polarization directions).

[0052] By using a polarizer, the angle α between its polarization direction and the polarization direction of the incident laser is changed. When α changes, according to Malus's law, rotating the polarizer will differentially adjust the transmission intensity of the incident laser, thereby achieving dynamic control of the proportion of laser intensity irradiated to different irradiation areas.

[0053] Step 4 - Demix the mixed Raman spectra to obtain the pure Raman spectra excited in m irradiation regions. Details are as follows:

[0054] In this embodiment, the expression for the mixed Raman spectrum is: a 1n ×Signalα1+a 2n ×Signalα² + … + a mn ×Signalαm+Noisen=Spectrumβn, where, a mn Let be the laser scaling factor of the irradiated region αm during the nth acquisition, SignalAm be the Raman scattering information excited in the irradiated region αm, Noisen be the noise, and Spectrumβn be the mixed Raman spectrum of the nth acquisition.

[0055] Furthermore, the unmixing process includes: removing noise using spectral data processing methods to obtain a 1n ×Signalα1+a 2n ×Signalα² + … + a mn×Signalαm=Spectrumβn-Noisen,,and Signalα1, Signalα2……and Signalαm can be obtained by fitting and analyzing. Here, spectral data processing methods refer to techniques for removing noise by analyzing and processing mixed Raman spectral data. Spectral data processing methods can be any one or more of the following: statistical methods, chemometric modeling, artificial intelligence analysis models, etc., as used in existing technologies.

[0056] This embodiment provides a second aspect as follows: Figure 2 The apparatus shown for detecting Raman spectra corresponds to the aforementioned method for detecting Raman spectra. The apparatus includes:

[0057] A laser source is used to provide illumination. During testing, a laser of appropriate power is selected, along with a suitable integration time range for the spectral measurement device. Preferred center wavelengths of the laser source output include, but are not limited to: 257±0.5nm, 261±0.5nm, 266±0.5nm, 320±0.5nm, 355±0.5nm, 360±0.5nm, 366±0.5nm, and 405±0.5nm. 457±0.5nm, 473±0.5nm, 488±0.5nm, 514.5±0.5nm, 532±0.5nm, 561±0.5nm, 589±0.5nm, 633± 0.5nm, 660±0.5nm, 671±0.5nm, 785±0.5nm, 808±0.5nm, 830±0.5nm, 980±0.5nm, 1064±0.5nm.

[0058] The irradiation modulation module includes an offset preset component and a ratio control unit. The offset preset component is used to preset spatial offsets δ1, δ2, ..., δm relative to the signal collection area β on the sample. The position of the spatial offset δm is defined as the irradiation area αm. The offset preset component includes a beam splitting element, which splits the laser beam to form different irradiation areas on the sample surface. The ratio control unit is used to adjust the laser ratio among the m irradiation areas. The ratio control unit can be, but is not limited to, a polarizer, waveplate, filter, beam splitter, or laser duty cycle adjustment unit.

[0059] The detection module is used to acquire the mixed Raman spectrum of the signal collection region. The detection module includes a spectrometer (e.g., a grating with a focal length of 500 mm and a resolution of 1 cm⁻¹). -1 Specifications) and CCD components;

[0060] The processing module is used to demix the mixed Raman spectra to obtain pure Raman spectra excited in all irradiation regions. The processing module can employ any existing industrial computer, which runs spectral data processing methods to solve for multiple sets of mixed Raman spectra and output pure Raman spectra.

[0061] Regarding the location layout and connection relationships:

[0062] The proportional control unit is located at the emission end of the laser source;

[0063] The offset preset component is positioned along the optical path at the output end of the proportional control unit;

[0064] The detection module is located on the Raman signal receiving side of the sample;

[0065] The signal input terminal of the processing module is electrically connected to the signal output terminal of the detection module.

[0066] It should be noted that the above positional layout and connection relationship is only a preferred embodiment of this invention. In practical applications, the corresponding optical relationship can also be achieved by adapting the positional relationship (such as swapping the positions of the proportional control unit and the offset preset component). For those skilled in the art, based on the description in this application, they can conceive of the corresponding relationship without creative effort. Therefore, this embodiment will not be elaborated upon here.

[0067] In a preferred embodiment of this invention, the device further includes an optical component disposed between at least one of the following: the laser and irradiation modulation module, the sample and irradiation modulation module, and the sample and detection module. That is, the optical component may be disposed separately before the laser and irradiation modulation module, between the sample and irradiation modulation module, or between the sample and detection module; it may also be disposed simultaneously between the laser and irradiation modulation module and between the sample and irradiation modulation module, or between the sample and irradiation modulation module and between the sample and detection module; or it may be disposed between the laser and irradiation modulation module, between the sample and irradiation modulation module, and between the sample and detection module. The optical component is used to guide the laser to the sample and form a predetermined spatial offset. The optical component includes a deflecting element for generating a predetermined spatial offset of the laser beam, and an optical path guiding element, such as a birefringent lens or a quartz lens, for guiding the offset laser beam to the sample.

[0068] In the embodiments provided in this application, it should be understood that the embodiments described herein can be implemented in hardware, software, firmware, middleware, code, or any suitable combination thereof. For hardware implementation, the processor may be implemented in one or more of the following: application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, other electronic units designed to implement the functions described herein, or combinations thereof. For software implementation, some or all of the processes of the embodiments may be performed by a computer program instructing the associated hardware. During implementation, the program may be stored in a computer-readable storage medium or transmitted as one or more instructions or code on a computer-readable storage medium. Computer-readable storage media include computer storage media and communication media, wherein communication media include any medium that facilitates the transmission of a computer program from one place to another. Storage media may be any available medium accessible to a computer. Computer-readable storage media may include, but are not limited to, RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage media or other magnetic storage devices, or any other medium capable of carrying or storing desired program code having the form of instructions or data structures and accessible to a computer.

[0069] Finally, it should be noted that the above description is only a preferred embodiment of this application and is not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for detecting Raman spectra, characterized in that, The method includes the following steps: Two or more irradiation areas are set on the sample, namely irradiation areas α1, α2, α3, ..., αm. The spatial offset of irradiation area α1 relative to signal collection area β is δ1, the spatial offset of irradiation area α2 is δ2, the spatial offset of irradiation area α3 is δ3, ..., the spatial offset of irradiation area αm is δm, and δ1, δ2, δ3, ..., δm are preset parameters. The laser simultaneously irradiates m irradiation areas; Adjust the ratio of laser power applied to the m irradiation areas and repeatedly collect the mixed Raman spectrum of the signal collection area; The mixed Raman spectra are demixed to obtain pure Raman spectra excited by m irradiation regions.

2. The method for detecting Raman spectra according to claim 1, characterized in that, The spatial offset is determined in the following way: Laser beam splitting is achieved by using a beam splitter, and different beams form different irradiation areas on the sample surface.

3. The method for detecting Raman spectra according to claim 1, characterized in that, The adjustment of the laser power ratio among the m irradiation areas includes the following steps: The laser ratio is adjusted by a proportional control unit; wherein the proportional control unit uses a proportional adjustment method including polarization adjustment, intensity adjustment or duty cycle adjustment.

4. The method for detecting Raman spectra according to claim 1, characterized in that, The expression for the mixed Raman spectrum is: a 1n ×Signalα1+a 2n ×Signalα² + … + a mn ×Signalαm+Noisen=Spectrumβn, where, a mn Let αm be the laser scaling factor of the irradiated region αm during the nth acquisition, Signalαm be the Raman scattering information excited in the irradiated region αm, Noisen be the noise, and Spectrumβn be the mixed Raman spectrum of the nth acquisition.

5. The method for detecting Raman spectra according to claim 4, characterized in that, The method of demixing the mixed Raman spectra to obtain pure Raman spectra excited in m irradiation regions includes the following steps: Noise was removed using spectral data processing methods to obtain a 1n ×Signalα1+a 2n ×Signalα² + … + a mn ×Signalαm=Sepctrumβn-Noisen, and analyze Signalα1, Signalα2……and Signalαm.

6. An apparatus for detecting Raman spectra, characterized in that, The device includes: A laser source is used to provide illumination with laser light. The irradiation modulation module includes an offset preset component and a ratio control unit; the offset preset component is used to preset spatial offsets δ1, δ2, ..., δm relative to the signal collection area β on the sample, wherein the position of the spatial offset δm is defined as the irradiation area αm; the ratio control unit is used to adjust the laser ratio between the m irradiation areas. The detection module is used to acquire the mixed Raman spectrum of the signal collection region; The processing module is used to process and output the mixed Raman spectrum.

7. The apparatus for detecting Raman spectra according to claim 6, characterized in that, The offset preset component includes a beam splitting element. After the beam splitting element splits the laser beam, it forms irradiation areas α1, α2, ... and αm on the sample surface.

8. The apparatus for detecting Raman spectra according to claim 6, characterized in that, The proportional control unit includes a polarizer, waveplate, filter, beam splitter, or laser duty cycle adjustment unit.

9. The apparatus for detecting Raman spectra according to claim 6, characterized in that, The device also includes an optical component; the optical component is disposed between at least one of the following: a laser and an irradiation modulation module, a sample and an irradiation modulation module, and a sample and a detection module; the optical component is used to guide the laser to the sample and form a preset spatial offset.

10. The apparatus for detecting Raman spectra according to claim 6, characterized in that, The processing module demixes the mixed Raman spectra using a preset spectral data processing method.

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