Spatial offset Raman spectroscopy detection system

Abstract

The present invention provides a spatially offset Raman spectroscopy detection system. The SORS optical path device is used to collect Raman signals and focus the Raman signals to the input end of a collection fiber bundle. The collection fiber bundle includes a circular input end and a linear output end. The circular input end is used to receive the offset Raman signals focused by the SORS optical path device from the sample. Taking the excitation position as the origin, the diameter of the collection fiber bundle and / or the number of collection fibers included increase with the increase of the spatial offset amount to compensate for the Raman signals weakened with the increase of the spatial offset amount. The linear output end of the fiber bundle is used to convert the circular arrangement at the circular input end into a linear arrangement and couple it with the entrance slit of the spectrometer. The present invention can effectively solve the problem of weak Raman signal intensity at a large spatial offset position in a conventional SORS device or optical path, and reduce the signal intensity difference between the zero position and the maximum position of the spatial offset amount.

Description

Technical Field

[0001] The present invention relates to a spectral detection device, and particularly to a spatially offset Raman spectroscopy detection system. Background Art

[0002] Raman spectroscopy can reflect the vibration information of molecular substances and has good chemical specificity, so it is widely used in the fields of food, medicine and biological detection. Traditional Raman spectroscopy can only detect the information on the surface layer of the sample or penetrate through the transparent surface layer for detection. The new spatially offset Raman spectroscopy (SORS) was first proposed by British scientist A.W. Parker in 2005 (related patent numbers: US7652763, CN101115987, EP1828753, US7911604, GB2457212, AU2005313145, JP5449712007). SORS can penetrate through the opaque surface layer or outer packaging of the sample to obtain the chemical information carried by deeper substances. Therefore, the spatially offset Raman spectroscopy technology has a wide range of applications in non-destructive deep detection, such as non-invasive detection of blood components, rapid identification of drug quality, search for concealed hazardous chemicals, etc. These applications all require rapid judgment of the chemical specific characteristics of substances and the acquisition of deep information of opaque samples.

[0003] The principle of SORS is based on the theory of Raman scattered photon migration. Incident laser can excite Raman scattered photons both on the surface layer and in the deep interior of the sample. The scattered photons in the deep layer are more likely to undergo lateral migration than those on the surface layer. After multiple scattering, they finally reach the surface layer of the sample and are collected by the detector. Relative to the laser incident point, the Raman scattered photons at the offset distance Δ come from different sample depths ΔH. Therefore, the greater the distance from the incident point, the greater the proportion of Raman photons from deeper substances when collecting signals from the sample surface area.

[0004] In the existing SORS technology, there is a problem that the greater the spatial offset Δ, the weaker the Raman signal. The solutions are: moving the position of the incident laser or the collection optical fiber for step-by-step sampling, or adjusting the position of the optical elements in the collection optical path to control the spatial offset. However, the emission position of Raman photons on the sample surface and the collection position of the detector are in a conjugate relationship. When the magnification of the optical system is limited, the change in the collection position corresponding to the spatial offset Δ is usually very small, often in the order of dozens of μm or even smaller. Manual adjustment will produce large errors and poor repeatability, and electric precision adjustment will introduce complex system structures and higher costs. Summary of the Invention

[0005] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a spatially offset Raman spectroscopy detection system, which is used to solve the problem in the prior art that the larger the spatial offset of SORS technology, the weaker the Raman signal.

[0006] To achieve the above purpose and other related purposes, the present invention provides a spatially offset Raman spectroscopy detection system, and the spatially offset Raman spectroscopy detection system includes: a SORS optical path device, a collection optical fiber bundle, and a spectrometer;

[0007] The SORS optical path device is used to collect Raman signals and focus the Raman signals to the input end of the collection optical fiber bundle;

[0008] The collection optical fiber bundle includes a circular input end and a linear output end. The circular input end is used to receive the offset Raman signals focused by the SORS optical path device. The central position of the collection optical fiber bundle corresponds to the sample area with a spatial offset of zero. The collection optical fiber at this central position is single. Taking the excitation position as the origin, the diameter of the collection optical fiber bundle and / or the number of collection optical fibers included increase with the increase of the spatial offset, compensating for the Raman signals weakened with the increase of the spatial offset;

[0009] The linear output end of the optical fiber bundle is used to convert the circular arrangement at the circular input end into a linear arrangement and couple it with the entrance slit of the spectrometer.

[0010] Optionally, the fiber arrangement at the circular input end of the optical fiber bundle follows the principle of central symmetry, and the circular collection optical fiber area corresponding to each level of offset is a standard circle to ensure that the spatial offsets corresponding to the signals on the same level of circular collection optical fibers are the same.

[0011] Optionally, taking the collection optical fiber at the central position as the zero-level offset, starting from the first-level circular collection optical fiber, the number of the collection optical fibers in each increasing level is equal or increasing, and the diameter of the circular collection optical fiber is increasing. The rest of the circular collection optical fiber area is filled with non-light-passing dark fibers.

[0012] Optionally, starting from the first-level circular collection optical fiber, the number of the collection optical fibers in each increasing level is increasing, and the number of collection optical fibers included in the circular collection optical fiber is 4N, where N is the level number of the current circular collection optical fiber.

[0013] Optionally, including the collection optical fiber at the zero-level offset, the collection optical fiber bundle includes at least five levels of circular collection optical fibers with equal-spacing offsets, which are used for collecting offset Raman spectroscopy signals.

[0014] Optionally, the SORS optical path device includes: a laser, a laser collimation system, an optical path conversion device, a focusing and collecting optical system, and a coupling optical system; the laser and the laser collimation system are used to output a collimated parallel laser beam; the optical path conversion device is used to reflect the laser beam and pick out the Raman signal; the focusing and collecting optical system is used to focus the laser beam reflected by the optical path conversion device, and at the same time collect the Raman signal beam and collimate it into a parallel beam, wherein the sample is placed at the focal plane position of the focusing and collecting optical system; the coupling optical system is used to focus the Raman signal beam collimated by the focusing and collecting optical system and couple it to the circular input end of the collection fiber bundle, and the circular input end is placed at the focal plane position of the coupling optical system; the collection fiber bundle is used to collect Raman signal photons and input them into the spectrometer through the linear output end for image acquisition and analysis.

[0015] Optionally, based on the optical path conjugate characteristic of the SORS optical path device, the center of the circular input end of the collection fiber bundle corresponds to the position where the sample spatial offset is zero, and the radius R of each outer ring of collection fibers i and the corresponding sample spatial offset Δ i satisfy the following relationship: R i = Δ i × f 5 / f 4 where f 4 is the focal length of the focusing and collecting optical system, and f 5 is the focal length of the coupling optical system.

[0016] Optionally, all the fibers on each ring-shaped collection area of the circular input end are arranged closely adjacent to each other at the linear output end, and the fibers in different ring-shaped collection areas are separated by a dark fiber at the linear output end to reduce the crosstalk between the Raman signals corresponding to different spatial offsets.

[0017] As described above, the spatial offset Raman spectroscopy detection system of the present invention has the following beneficial effects:

[0018] For the present invention, in the area with a large spatial offset and weak Raman signal, the corresponding number of sampling fibers is large, and more Raman signals can be collected;

[0019] Within the designed spatial offset acquisition range of the present invention, the position of the collection fiber bundle does not need to be adjusted, and the Raman signals corresponding to multiple different spatial offsets can be collected at one time, reducing the workload of spectrum acquisition, and at the same time avoiding the measurement error caused by the mechanical position adjustment of the fiber bundle.

[0020] The present invention can effectively solve the problem of weak Raman signal intensity at large spatial offset positions in a conventional SORS device or optical path, reduce the signal intensity difference between the zero and maximum spatial offset amounts, and can simultaneously collect Raman signals at multiple specified spatial offset positions, avoiding the large workload caused by time-sharing acquisition, the measurement errors introduced by the variation of individual biological tissue characteristics over time, and the offset errors introduced by the optical path adjustment and mechanical adjustment of the collection fiber position. Description of the Drawings

[0021] Figure 1 It shows a schematic structural diagram of the spatial offset Raman spectroscopy detection system in an embodiment of the present invention.

[0022] Figure 2 It shows a fiber layout diagram of the circular input end and linear output end of the collection fiber bundle for Arrangement Scheme A.

[0023] Figure 3 It shows a corresponding relationship diagram of the positions of each fiber at the circular input end and linear output end of the collection fiber bundle for Arrangement Scheme A.

[0024] Figure 4 It shows a fiber layout diagram of the circular input end and linear output end of the collection fiber bundle for Arrangement Scheme B.

[0025] Figure 5 It shows a corresponding relationship diagram of the positions of each fiber at the circular input end and linear output end of the collection fiber bundle for Arrangement Scheme B.

[0026] Figure 6 It shows a fiber layout diagram of the circular input end and linear output end of the collection fiber bundle for Arrangement Scheme C.

[0027] Figure 7 It shows a corresponding relationship diagram of the positions of each fiber at the circular input end and linear output end of the collection fiber bundle for Arrangement Scheme C.

[0028] Figure 8 It shows a fiber layout diagram of the circular input end and linear output end of the collection fiber bundle for Arrangement Scheme D.

[0029] Figure 9 It shows a corresponding relationship diagram of the positions of each fiber at the circular input end and linear output end of the collection fiber bundle for Arrangement Scheme D.

[0030] Figure 10 It shows a fiber layout diagram of the circular input end and linear output end of the collection fiber bundle for Arrangement Scheme E.

[0031] Figure 11 It shows a corresponding relationship diagram of the positions of each fiber at the circular input end and linear output end of the collection fiber bundle for Arrangement Scheme E.

[0032] Figure 12 The circular input end and linear output end optical fiber layout diagram of the collection optical fiber bundle shown as layout scheme F.

[0033] Figure 13 The corresponding relationship diagram of the positions of each optical fiber at the circular input end and linear output end of the collection optical fiber bundle shown as layout scheme F.

[0034] Description of component labels

[0035] 10 SORS optical path device

[0036] 101 Laser

[0037] 102 Laser collimation system

[0038] 103 Optical path conversion device

[0039] 104 Focusing and collecting optical system

[0040] 105 Coupling optical system

[0041] 20 Collection optical fiber bundle

[0042] 30 Spectrometer Detailed implementation manners

[0043] The following illustrates the implementation manners of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0044] When detailing the embodiments of the present invention, for the sake of convenience of description, the cross-sectional views showing the device structure will be enlarged locally not in accordance with the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention here. In addition, in actual production, three-dimensional spatial dimensions including length, width and depth should be included.

[0045] For the convenience of description, spatial relationship terms such as "under", "below", "lower than", "beneath", "above", "on" etc. may be used herein to describe the relationship between one element or feature shown in the drawings and other elements or features. It will be understood that these spatial relationship terms are intended to encompass other directions of the device in use or operation in addition to the directions depicted in the drawings. In addition, when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or there can also be one or more layers in between.

[0046] In the context of the present application, the structure in which the described first feature is "above" the second feature may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0047] It should be noted that the diagrams provided in this embodiment only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The types, quantities, and proportions of the components in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0048] As Figure 1 shown, this embodiment provides a spatially offset Raman spectroscopy detection system, and the spatially offset Raman spectroscopy detection system includes: a SORS optical path device 10, a collection optical fiber bundle 20, and a spectrometer 30;

[0049] The SORS optical path device 10 is used to collect Raman signals and focus the Raman signals to the input end of the collection optical fiber bundle.

[0050] As Figure 1 shown, the SORS optical path device 10 includes: a laser 101, a laser collimation system 102, an optical path conversion device 103, a focusing and collection optical system 104, and a coupling optical system 105; the laser 101 and the laser collimation system 102 are used to output a collimated parallel laser beam; the optical path conversion device 103 is used to reflect the laser beam and pick out the Raman signal; the focusing and collection optical system 104 is used to focus the laser beam reflected by the optical path conversion device 103, and at the same time collect the Raman signal beam and collimate it into a parallel beam, wherein the sample is placed at the focal plane position of the focusing and collection optical system 104; the coupling optical system 105 is used to focus and couple the Raman signal beam collimated by the focusing and collection optical system 104 to the circular input end of the collection optical fiber bundle 20, and the circular input end is placed at the focal plane position of the coupling optical system 105; the collection optical fiber bundle 20 is used to collect Raman signal photons and input them into the spectrometer 30 through a linear output end for image acquisition and analysis.

[0051] The collection fiber bundle 20 includes a circular input end and a linear output end. The circular input end is used to receive the offset Raman signal focused by the SORS optical path device 10. The central position of the collection fiber bundle 20 corresponds to the sample area with a spatial offset of zero. The collection fiber at this central position is a single fiber. Taking the excitation position as the origin, the diameter of the collection fiber bundle 20 or / and the number of collection fibers it contains shows an increasing trend as the spatial offset increases, so as to compensate for the Raman signal that weakens with the increase of the spatial offset. The linear output end of the fiber bundle is used to convert the circular arrangement at the circular input end into a linear arrangement and couple it with the entrance slit of the spectrometer 30.

[0052] The fiber arrangement at the circular input end of the fiber bundle follows the principle of central symmetry, and the circular collection fiber area corresponding to each level of offset is a standard circle, so as to ensure that the spatial offsets corresponding to the signals on the same-level circular collection fibers are the same.

[0053] Based on the optical path conjugate characteristic of the SORS optical path device 10, the center of the circular input end of the collection fiber bundle 20 corresponds to the position where the sample spatial offset is zero. The radius R of the outermost circular collection fibers at each level i and the corresponding sample spatial offset Δ i satisfy the following relationship: R i = Δ i × f 5 / f 4 where f 4 is the focal length of the focusing and collecting optical system 104, and f 5 is the focal length of the coupling optical system 105. For example, for fibers with a cladding diameter of 125 μm, the radii R of the circular collection fibers at each level of the circular input end i are approximately 0, 125 μm, 250 μm, 375 μm, 500 μm respectively. With the system magnification f 5 / f 4 = 2.5 of the standard SORS optical path device 10, Raman signals at positions with spatial offsets of approximately 0, 50 μm, 100 μm, 150 μm, 200 μm on the sample can be collected. That is, by gradually increasing the radius of the circular collection fibers, Raman signals with different spatial offsets can be collected.

[0054] Taking the collection fiber at the central position as the zero-level offset, starting from the first-level circular collection fiber, the number of the collection fibers (i.e., the through fiber cores) at each increasing level is equal or increasing, and the diameter of the circular collection fibers is increasing. The remaining areas of the circular collection fibers are filled with non-light-passing dark fibers (i.e., dark cores).

[0055] For example, starting from the first-stage annular collection optical fiber, the number of the collection optical fibers at each increasing stage is increasing, and the number of the collection optical fibers included in the annular collection optical fiber is 4N, where N is the stage number of the current annular collection optical fiber. In this embodiment, including the collection optical fiber with zero offset level, the collection optical fiber bundle 20 includes at least five stages of annular collection optical fibers with equally spaced offsets, which are used for collecting the offset Raman spectral signal.

[0056] Preferably, Figure 2 is Arrangement Scheme A of the layout of a collection optical fiber bundle 20 in the embodiment. Among them, Figure 3 The upper part shows the circular input end structure of the collection optical fiber bundle 20, and the lower part shows the linear output end structure of the collection optical fiber bundle 20. The overall circular input end of the collection optical fiber bundle 20 is a five-stage annular structure, with a single collection optical fiber at the center. The first, second, third, and fourth rings respectively have 4, 8, 12, and 16 optical fibers for collecting Raman signals, and the rest is filled with non-light-passing dark fibers. In this embodiment, by setting the number of the collection optical fibers at each increasing stage to be increasing, the Raman signal weakened with the increase of the spatial offset can be effectively compensated.

[0057] All the collection optical fibers on each stage of the annular collection area of the circular input end are arranged closely adjacent to each other at the linear output end. The collection optical fibers in different-stage annular collection areas are separated by a single dark fiber at the linear output end to reduce the crosstalk between the Raman signals corresponding to different spatial offsets. For example, Figure 3 is the corresponding relationship of the position distribution of all the light-passing optical fibers included in the collection optical fiber bundle 20 of Arrangement Scheme A at the circular input end and the linear output end. All the collection optical fibers on each stage of the annular collection optical fiber at the circular input end are arranged closely adjacent to each other at the linear end. The collection optical fibers in different-stage annular collection optical fibers are separated by a single dark fiber at the linear end to reduce the crosstalk between the Raman signals corresponding to different spatial offsets. Among them, the redundant dark fibers are removed at the linear output end to limit the size of the output end, as Figure 3 shown in the linear output end structure of the collection optical fiber bundle 20 below.

[0058] Figure 4 、 6 8, 10, 12 are the other five arrangement schemes B, C, D, E, and F of the collection optical fiber bundle 20 in the embodiment. The structures are all similar to the collection optical fiber bundle 20 of Arrangement Scheme A and are composed of a five-stage annular structure, with a single optical fiber at the center. Of course, starting from the first-stage annular collection optical fiber, the number of the collection optical fibers at each increasing stage can be equal or increasing. For example, Figure 4It is Arrangement Scheme B for collecting the fiber optic bundle 20 in the embodiment. The overall circular input end of the fiber optic bundle 20 is a 5-level ring structure. There is one collecting optical fiber at the center. The 1st, 2nd, 3rd, and 4th rings respectively have 6, 6, 6, and 12 optical fibers for collecting Raman signals, and the rest is filled with non-light-passing dark fibers. Figure 6 It is Arrangement Scheme C for collecting the fiber optic bundle 20 in the embodiment. The overall circular input end of the fiber optic bundle 20 is a 5-level ring structure. There is one collecting optical fiber at the center. The 1st, 2nd, 3rd, and 4th rings respectively have 6, 6, 12, and 18 optical fibers for collecting Raman signals, and the rest is filled with non-light-passing dark fibers. Figure 8 It is Arrangement Scheme D for collecting the fiber optic bundle 20 in the embodiment. The overall circular input end of the fiber optic bundle 20 is a 5-level ring structure. There is one collecting optical fiber at the center. The 1st, 2nd, 3rd, and 4th rings respectively have 6, 6, 6, and 12 optical fibers for collecting Raman signals, and the rest is filled with non-light-passing dark fibers. Figure 10 It is Arrangement Scheme E for collecting the fiber optic bundle 20 in the embodiment. The overall circular input end of the fiber optic bundle 20 is a 5-level ring structure. There is one collecting optical fiber at the center. The 1st, 2nd, 3rd, and 4th rings respectively have 6, 6, 12, and 12 optical fibers for collecting Raman signals, and the rest is filled with non-light-passing dark fibers. Figure 12 It is Arrangement Scheme F for collecting the fiber optic bundle 20 in the embodiment. The overall circular input end of the fiber optic bundle 20 is a 5-level ring structure. There is one collecting optical fiber at the center. The 1st, 2nd, 3rd, and 4th rings respectively have 4, 6, 10, and 14 optical fibers for collecting Raman signals, and the rest is filled with non-light-passing dark fibers.

[0059] Figure 5 、 7 9, 11, 13 are the corresponding relationships of the position distributions of all light-passing optical fibers included in the fiber optic bundle 20 of the above Arrangement Schemes B, C, D, E, and F at the circular input end and the linear output end. Their structures are all similar to that of the fiber optic bundle 20A. All the collecting optical fibers on each level of the circular collecting optical fibers at the circular input end are arranged closely adjacent to each other at the linear end, and the collecting optical fibers on different levels of the circular collecting optical fibers are separated by one dark fiber at the linear end.

[0060] In this embodiment, the incident laser is focused and irradiated on the sample from the standard SORS optical path device 10. According to the photon migration theory, the farther the sample position is from the irradiation point, the greater the probability that the collected Raman signal comes from deep tissues. In the circular regions with the same spatial distance from the irradiation point, the sample depth information corresponding to the generated Raman signals is basically the same. At the circular input ends of the fiber optic bundles 20A, B, C, D, and E, F, the number of optical fibers is more at positions farther from the center, compensating for the Raman signals weakened with the increase of the spatial offset.

[0061] As described above, the spatial offset Raman spectroscopy detection system of the present invention has the following beneficial effects:

[0062] For the regions with large spatial offsets and weak Raman signals in the present invention, the corresponding number of sampling optical fibers is large, and more Raman signals can be collected;

[0063] Within the designed spatial offset acquisition range of the present invention, the position of the collection fiber bundle 20 does not need to be adjusted, and Raman signals corresponding to multiple levels of different spatial offsets can be collected at one time, reducing the workload of spectrum acquisition. At the same time, it also avoids the measurement errors caused by the mechanical position adjustment of the fiber bundle.

[0064] The present invention can effectively solve the problem of weak Raman signal intensity at large spatial offset positions in conventional SORS devices or optical paths, reduce the signal intensity difference between the zero and maximum spatial offset positions, and can simultaneously collect Raman signals at multiple specified spatial offset positions, avoiding the large workload caused by time-sharing acquisition, the measurement errors introduced by the changes in individual biological tissue characteristics over time, and the offset errors introduced by the optical path adjustment and the mechanical adjustment of the collection fiber position.

[0065] Therefore, the present invention effectively overcomes various disadvantages in the prior art and has high industrial utilization value.

[0066] The above embodiments are only illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A spatially offset Raman spectroscopy detection system, characterized in that, the spatially offset Raman spectroscopy detection system comprises: a SORS optical path device, a collection optical fiber bundle, and a spectrometer; the SORS optical path device is used for collecting Raman signals and focusing the Raman signals to the input end of the collection optical fiber bundle; the collection optical fiber bundle comprises a circular input end and a linear output end. The circular input end is used for receiving the offset Raman signals focused by the SORS optical path device to simultaneously collect Raman signals corresponding to multiple different spatial offset amounts. The central position of the collection optical fiber bundle corresponds to a sample region with a spatial offset amount of zero. The collection optical fiber at this central position is a single fiber. Taking the excitation position as the origin, the diameter of the collection optical fiber bundle or / and the number of collection optical fibers it contains shows an increasing trend as the spatial offset amount increases to compensate for the weakened Raman signals as the spatial offset amount increases. Taking the collection optical fiber at the central position as the zero-level offset, starting from the first-level annular collection optical fibers, the number of collection optical fibers in each increasing level is equal or increasing, and the diameter of the annular collection optical fibers is increasing. The remaining regions of the annular collection optical fibers are filled with non-light-passing dark fibers; the fiber arrangement at the circular input end of the optical fiber bundle follows the principle of central symmetry, and the annular collection optical fiber region corresponding to each level of offset amount is a standard circle to ensure that the spatial offset amounts corresponding to the signals on the same-level annular collection optical fibers are the same; all the optical fibers on each level of annular collection region at the circular input end are arranged closely adjacent to each other at the linear output end. The optical fibers in different-level annular collection regions are separated by a single dark fiber at the linear output end to reduce the crosstalk between Raman signals corresponding to different spatial offset amounts; the linear output end of the optical fiber bundle is used for converting the circular arrangement at the circular input end into a linear arrangement and coupling it with the entrance slit of the spectrometer.

2. The spatially offset Raman spectroscopy detection system according to claim 1, characterized in that: starting from the first-level annular collection optical fibers, the number of collection optical fibers in each increasing level is increasing, and the number of collection optical fibers contained in the annular collection optical fibers is 4N, where N is the level number of the current annular collection optical fibers.

3. The spatially offset Raman spectroscopy detection system according to claim 1, characterized in that: including the collection optical fiber at the zero-level offset, the collection optical fiber bundle comprises at least five levels of annular collection optical fibers with equal spacing offsets for collecting offset Raman spectroscopy signals.

4. The spatially offset Raman spectroscopy detection system according to claim 1, characterized in that, the SORS optical path device comprises: a laser, a laser collimation system, an optical path conversion device, a focusing and collection optical system, and a coupling optical system; the laser and the laser collimation system are used for outputting a collimated parallel laser beam; the optical path conversion device is used for reflecting the laser beam and detecting Raman signals; the focusing and collection optical system is used for focusing the laser beam reflected by the optical path conversion device, simultaneously collecting the Raman signal beam and collimating it into a parallel beam, wherein the sample is placed at the focal plane position of the focusing and collection optical system. The coupling optical system is used to focus and couple the Raman signal beam collimated by the focusing and collecting optical system to the circular input end of the collection fiber bundle, and the circular input end is placed at the focal plane position of the coupling optical system; the collection fiber bundle is used to collect Raman signal photons and input them into a spectrometer through a linear output end for image acquisition and analysis.

5. The spatially offset Raman spectroscopy detection system according to claim 4, wherein, Based on the optical path conjugate characteristics of the SORS optical path device, collect the position where the center of the circular input end of the fiber bundle corresponds to a zero sample space offset, and the radius R of each outer ring of collecting fibers i and the corresponding sample space offset Δ i satisfy the following relationship: R i = Δ i × f 5 / f 4 , where f 4 is the focal length of the focusing collection optical system, and f 5 is the focal length of the coupling optical system.

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