raman spectrometer

Abstract

This application discloses a Raman spectrometer applied in the field of optical technology. It includes a light source system, a multi-mode switching system, and a single-mode detection system. The light source system includes multiple types of light sources suitable for different spectral detection modes. The multi-mode switching system includes a light adjustment element group and multiple mode position regions, each corresponding to a spectral detection mode. It connects the sub-optical path system in the corresponding spectral detection mode by moving each optical element in the light adjustment element group to the corresponding mode position region. The single-mode detection system includes multiple sub-optical path systems, each corresponding to a spectral detection mode. The Raman spectrometer of this application is low-cost, small-sized, and multifunctional, meeting the practical needs for detecting various spectra.

Description

Technical Field

[0001] This application relates to the field of optical technology, and in particular to a Raman spectrometer. Background Technology

[0002] Raman spectroscopy is an optical instrument based on Raman technology. Due to its advantage of being able to qualitatively or quantitatively identify molecular "fingerprint information" non-destructively, it has gradually gained widespread attention in medicine, minerals, archaeology, and other fields, especially playing an important role in nanomaterials and single-cell biological analysis. When a single wavelength of incident light is focused on a sample, the excited scattered light contains not only scattered light of the same frequency as the incident light, but also scattered light of different frequencies (either increased or decreased). The former is Rayleigh scattering, and the latter is Raman scattering. Compared to Rayleigh scattering, the Raman scattering signal is extremely weak, approximately 10 times the intensity of Rayleigh scattering. -6 Raman spectroscopy is used to study and analyze molecular structure by detecting the Raman scattered light from molecules to obtain vibrational and rotational fingerprint information.

[0003] The Raman spectrometers in related technologies include laboratory-grade large Raman spectrometers and portable Raman spectrometers. For laboratory-grade large Raman spectrometers, although they meet the requirements of multi-functional spectral detection, their optical systems are complex, large in size, and expensive. For portable Raman spectrometers, since their overall optical system uses miniaturized optical elements to reduce the size of the overall optical system, the functions of this type of Raman spectrometer are limited and can only meet the needs of Raman spectral detection.

[0004] Therefore, how to prepare a Raman spectrometer that simultaneously meets the requirements of low cost, small size, and multifunctionality is a technical problem that needs to be solved by those skilled in the art. Summary of the Invention

[0005] This application provides a Raman spectrometer that is low-cost, small in size, and multifunctional, and can meet the practical needs of detecting various spectra.

[0006] To address the aforementioned technical problems, the embodiments of the present invention provide the following technical solutions:

[0007] This invention provides a Raman spectrometer, including a light source system, a multi-mode switching system, and a single-mode detection system;

[0008] The light source system includes multiple types of light sources suitable for different spectral detection modes;

[0009] The multi-mode switching system includes a light adjustment element group and multiple mode position areas, each mode position area corresponding to a spectral detection mode; it is used to connect the sub-optical path system in the corresponding spectral detection mode by moving each optical element in the light adjustment element group to the corresponding mode position area.

[0010] The single-mode detection system includes multiple sub-optical path systems, each of which corresponds to a spectral detection mode.

[0011] Optionally, the light source system includes a laser light source and / or a white light source and / or a broadband light source;

[0012] The laser source is used to emit a laser beam as a light source in both Raman spectroscopy detection mode and fluorescence spectroscopy detection mode.

[0013] The white light source serves as the light source for the white light microscopic imaging observation mode;

[0014] The broadband light source is used as the light source in the absorption spectroscopy detection mode.

[0015] Optionally, the spectral detection mode is a white light microscopy imaging observation mode, and the single-mode detection system includes a white light microscopy imaging observation sub-optical path system;

[0016] The white light microscopy imaging observation sub-optical path system includes a first lens, a first reflector, and an imaging device. The objective lens and the transmission-reflection functional element in the light adjustment element group are connected when they are in the white light mode position region. The white light source emitted beam passes through the first lens, the transmission-reflection functional element, and the objective lens and is incident on the first sample to be tested in the sample detection cell. The reflected light from the first sample to be tested passes through the objective lens, the transmission-reflection functional element, and the first reflector in sequence and is incident on the imaging device to perform white light microscopy imaging observation on the first sample to be tested.

[0017] Optionally, the light adjustment element group further includes a second reflector; the second reflector is located in the white light mode position area;

[0018] The reflected light from the first sample under test passes sequentially through the objective lens, the transmission and reflection functional element, the second reflector, and the first reflector before entering the imaging device to perform white light microscopic imaging observation of the first sample under test.

[0019] Optionally, the spectral detection mode is an absorption spectral detection mode, a Raman spectral detection mode, or a fluorescence spectral detection mode, and the single-mode detection system further includes a spectrophotometer.

[0020] The spectrophotometer includes a light propagation alteration element, a grating, a focusing element, and an image sensor; the incident light rays pass sequentially through the light propagation alteration element, the grating, and the focusing element before being projected onto the image sensor.

[0021] The grating includes a first grating and a second grating with different scribe number densities on their front and back sides, wherein the scribe number density of the first grating is less than that of the second grating.

[0022] Optionally, the spectral detection mode is an absorption spectral detection mode, and the single-mode detection system includes an absorption spectral detection sub-optical path system;

[0023] The absorption spectral detection sub-optical path system includes a second lens, a third mirror, a fourth mirror, a slit, and the spectrophotometer system. When the first grating of the grating is rotated to face the front, and all optical elements of the light adjustment element group are moved to the absorption mode position region, they are connected.

[0024] The broadband light source emits a beam that passes through the second lens and the third reflector and is incident on the second sample to be tested in the sample detection cell. The reflected light from the second sample to be tested passes through the fourth reflector, the third lens, and the slit in sequence and enters the spectrophotometer to perform absorption spectrum detection on the second sample to be tested.

[0025] Optionally, the spectral detection mode is a Raman spectral detection mode, and the single-mode detection system includes a Raman spectral detection sub-optical path system;

[0026] The Raman spectroscopy detection sub-optical path system includes a fourth mirror, a fifth mirror, a third lens, a slit, and the spectrometer system. When the second grating of the grating is rotated to face the front, and the first long-pass filter and the second long-pass filter of the light adjustment element group are located on the optical axis, all other optical elements in the Raman spectroscopy detection sub-optical path system are connected when they move to the Raman mode position region.

[0027] The laser beam emitted from the laser source passes through the fifth reflecting mirror, the first long-pass filter, and the objective lens of the light adjustment element group and is incident on the third sample to be tested in the sample detection cell. The reflected light from the third sample to be tested passes sequentially through the objective lens, the first long-pass filter, the second long-pass filter, the fourth reflecting mirror, the third lens, and the slit into the spectrophotometer system to perform Raman spectroscopy detection on the third sample to be tested.

[0028] Optionally, the Raman spectroscopy detection sub-optical path system further includes a neutral density filter and a laser beam expander;

[0029] The laser beam emitted from the laser source passes through the neutral density filter, the fifth reflecting mirror, the laser beam expander, the first long-pass filter, and the objective lens and is incident on the third sample to be tested.

[0030] Optionally, the incident angle position of the grating can be adjusted according to the Raman frequency shift detection range to perform Raman spectroscopy detection;

[0031] The incident angle is the angle between the front of the grating and the optical axis of the Raman spectroscopy detection sub-optical path system.

[0032] Optionally, the spectral detection mode is a fluorescence spectral detection mode, and the single-mode detection system includes a fluorescence spectral detection sub-optical path system;

[0033] The fluorescence spectroscopy detection sub-optical path system includes a fourth mirror, a fifth mirror, a third lens, a slit, and the spectrophotometer system. When the grating is rotated to the target position, and the first and second long-pass filters of the light adjustment element group are located on the optical axis, all other optical elements in the fluorescence spectroscopy detection sub-optical path system are connected when they have moved to the fluorescence mode position region. The target position is the front face of the grating and the angle between the grating and the optical axis, determined according to the current detection wavelength.

[0034] The laser beam emitted from the laser source passes through the fifth reflecting mirror, the first long-pass filter, and the objective lens of the light adjustment element group, and is incident on the fourth sample to be tested in the sample detection cell. The reflected light from the fourth sample to be tested passes sequentially through the objective lens, the first long-pass filter, the second long-pass filter, the fourth reflecting mirror, the third lens, and the slit into the spectrophotometer system to perform fluorescence spectral detection on the fourth sample to be tested in different wavelength bands.

[0035] Optionally, the fluorescence spectroscopy detection sub-optical path system further includes a neutral density filter and a laser beam expander;

[0036] The laser beam emitted from the laser source passes through the neutral density filter, the fifth reflecting mirror, the laser beam expander, the first long-pass filter, and the objective lens and is incident on the fourth sample to be tested.

[0037] Optionally, the spectrophotometer system further includes a sixth reflecting mirror; the incident light rays pass sequentially through the light propagation alteration element, the grating, the focusing element, and the sixth reflecting mirror before being projected onto the image sensor.

[0038] Optionally, a three-dimensional mobile platform may also be included;

[0039] The three-dimensional moving platform is used to carry the sample detection cell and moves the sample to the detection position by controlling the movement distance on the X, Y and Z axes.

[0040] Optionally, the sample detection cell may also hold a cuvette or a glass slide.

[0041] The advantages of the technical solution provided in this application are that it incorporates multiple light sources and corresponding optical path systems according to different spectral detection needs, and uses a multi-mode switching system to move each optical element to a designated area to achieve the switching of different detection modes, which can meet multiple spectral detection needs and meet the sensitivity and spectral resolution of scientific research-level spectral detection; the structure is simple and compact, and the entire optical path system is simpler and cheaper than laboratory-level large Raman instruments, thus realizing the fabrication of a low-cost, small-sized and multifunctional Raman spectrometer.

[0042] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0043] To more clearly illustrate the technical solutions of the embodiments of the present invention or related technologies, the drawings used in the description of the embodiments or related technologies 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.

[0044] Figure 1 A structural diagram of an optional embodiment of the Raman spectrometer provided in this invention;

[0045] Figure 2 This is a schematic diagram of the structural framework of an exemplary application scenario provided by an embodiment of the present invention;

[0046] Figure 3 This is a schematic diagram of the optical path structure of a Raman spectrometer in white light microscopic imaging observation mode provided in an embodiment of the present invention.

[0047] Figure 4 A schematic diagram of the optical path structure of a Raman spectrometer in absorption spectroscopy detection mode provided in an embodiment of the present invention;

[0048] Figure 5 This is a schematic diagram of the optical path structure of a Raman spectrometer in Raman spectroscopy detection mode provided in an embodiment of the present invention;

[0049] Figure 6 This is a schematic diagram of the optical path structure of a Raman spectrometer in fluorescence spectroscopy detection mode provided in an embodiment of the present invention.

[0050] Figure label:

[0051] 1-Light source system, 2-Multi-mode switching system, 3-Single-mode detection system, 4-Sample detection cell, 5-Three-dimensional moving platform, 11-Laser source, 12-White light source, 13-Broadband light source, 20-Moving switching platform, 21-Objective lens, 22-Transmission and reflection functional element, 23-Second reflecting mirror, 24-First long-pass filter, 25-Second long-pass filter, 201-First position area, 202-Second position area, 203-Third position area, 204- Default position area, 311-first lens, 312-first reflector, 313-camera, 321-light propagation alteration element, 322-grating, 323-focusing element, 324-image sensor, 325-sixth reflector, 331-second lens, 332-third reflector, 333-fourth reflector, 334-third lens, 335-slit, 341-fifth reflector, 342-neutral density filter, 343-laser beam expander. Detailed Implementation

[0052] To enable those skilled in the art to better understand the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely 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.

[0053] The terms "first," "second," "third," "fourth," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may include steps or units not listed. Various non-limiting embodiments of this application are described in detail below.

[0054] First see Figure 1 , Figure 1 This is a schematic flowchart of a Raman spectroscopy method provided by an embodiment of the present invention. The embodiment of the present invention may include the following:

[0055] The Raman spectrometer of this application may include a light source system 1, a multi-mode switching system 2, and a single-mode detection system 3. In order to obtain good spectral detection results, the optical path of the entire optical system of the Raman spectrometer is in a single plane.

[0056] The light source system 1 provides light sources for different spectral detection modes of the Raman spectrometer. It includes multiple types of light sources suitable for different spectral detection modes, and the types and number of light sources are determined according to the spectral detection modes supported by the Raman spectrometer. For example, if the Raman spectrometer supports Raman spectral detection and fluorescence spectral detection, the light source system 1 includes a laser light source 11; if the Raman spectrometer supports white light microscopic imaging observation, the light source system 1 includes a white light light source 12; and if the Raman spectrometer supports absorption spectral detection, the light source system 1 includes a broadband light source 13. Each spectral detection mode corresponds to a spectral detection function supported by the Raman spectrometer. In this embodiment, the Raman spectrometer can realize white light microscopic imaging observation, Raman spectral detection, absorption spectral detection, and fluorescence spectral detection functions. Accordingly, the spectral detection modes of the Raman spectrometer include white light microscopic imaging observation mode, absorption spectral detection mode, Raman spectral detection mode, and fluorescence spectral detection mode. Those skilled in the art can select the spectral detection functions implemented by the Raman spectrometer according to actual needs; this application does not impose any limitations in this regard. Accordingly, the light source system 1 may include a laser light source 11 and / or a white light source 12 and / or a broadband light source 13; the laser light source 11 is used to emit a laser beam as a light source in Raman spectroscopy detection mode and fluorescence spectroscopy detection mode; the white light source 12 is used as a light source in white light microscopic imaging observation mode; and the broadband light source 13 is used as a light source in absorption spectroscopy detection mode.

[0057] Since all optical components in the Raman spectrometer's optical path system, except for the grating and the optical elements in the multi-mode switching system 2, are fixedly arranged, this application achieves a small size, compact structure, and multifunctionality by moving the positions of the optical elements in the multi-mode switching system 2. This allows the optical paths of corresponding spectral detection modes to be connected by moving these optical elements into or out of the optical path. In this embodiment, the multi-mode switching system 2 includes a light adjustment element group and multiple mode position areas, each corresponding to a spectral detection mode. The multi-mode switching system 2 is used to connect the sub-optical path systems of the corresponding spectral detection mode by moving each optical element in the light adjustment element group to the corresponding mode position area. A mode position area refers to the position of each optical element in the light adjustment element group within the entire optical path system of the Raman spectrometer in a fixed spectral detection mode. Moving each optical element in the light adjustment element group to this position will connect the corresponding sub-optical path system of that spectral detection mode. The mode position area can be preset based on the entire optical path system of the Raman spectrometer. In other words, the positions of each optical element in the light adjustment element group under different spectral detection modes in the corresponding sub-optical path system are preset based on the entire optical path system of the Raman spectrometer. The combination of the positions of each optical element constitutes the mode position area. As an optional implementation, to facilitate operation and improve user experience, the user's commonly used spectral detection mode can be set as the default mode based on their personalized needs. The optical elements of the light adjustment element group are in the default mode positions. When other types of spectral detection functions, i.e., target spectral detection functions, are required, only the optical elements that can be connected to the sub-optical path system corresponding to the target spectral detection function need to be connected. Regarding the movement of the optical elements in the light adjustment element group, each optical element can be fixed to a limiting slider, and the optical elements can be moved to the corresponding positions by the limiting slider movement. Alternatively, the optical elements can be removed from the light adjustment element group and then placed back into their corresponding positions using a reset slot to achieve the switching of different spectral detection modes. Of course, to facilitate user adjustment of the relationship between changes in the observed optical path and changes in instrument performance, knobs can be installed at appropriate locations to adjust the moving distance or the angle between the optical element and the optical axis. The optical elements included in the light adjustment element group are used to adjust the propagation direction and wavelength of the incident light signal, and those skilled in the art can flexibly select according to actual needs. As an optional implementation, the light adjustment element group may include an objective lens 21, a transmission-reflection functional element 22, a first long-pass filter 24, and a second long-pass filter 25. Among them, the transmission-reflection functional element 22 may be a semi-transparent and semi-reflective mirror or a partially transparent and reflective mirror. To further improve the structural compactness, the light adjustment element group may also include a second reflecting mirror 23.

[0058] In this embodiment, the single-mode detection system 3 may include multiple sub-optical path systems, each corresponding to a spectral detection mode. A sub-optical path system comprises various optical elements and the optical path constructed from these elements to realize the corresponding spectral detection mode. For ease of description, the sub-optical path system corresponding to the white light microscopy imaging observation mode can be called the white light microscopy imaging observation sub-optical path system, the sub-optical path system corresponding to the absorption spectroscopy detection mode can be called the absorption spectroscopy detection sub-optical path system, the sub-optical path system corresponding to the Raman spectroscopy detection mode can be called the Raman spectroscopy detection sub-optical path system, and the sub-optical path system corresponding to the fluorescence spectroscopy detection mode can be called the fluorescence spectroscopy detection sub-optical path system.

[0059] Of course, Raman spectrometers inevitably include a sample detection cell 4, in which each sample to be tested is placed. The sample detection cell 4 can hold a cuvette and allow the light beam to pass through it; it can also hold a glass slide and allow the laser to irradiate the sample to be tested on the slide. To further improve the positioning accuracy of the sample to be tested, the sample detection cell 4 can be placed on a three-dimensional moving platform 5. That is, the three-dimensional moving platform 5 carries the sample detection cell 4, and by controlling the movement distance along the X, Y, and Z axes, the sample to be tested can be moved to the desired detection position. In other words, the three-dimensional moving platform 5 enables precise movement of the sample to be tested along the X, Y, and Z axes, thereby achieving precise positioning for the detection of the sample.

[0060] In the technical solution provided by the embodiments of the present invention, multiple light sources and corresponding optical path systems are built in according to different spectral detection requirements. The optical elements are moved to designated areas through a multi-mode switching system to achieve the switching of different detection modes. This can meet multiple spectral detection requirements and meet the sensitivity and spectral resolution of scientific research-level spectral detection. The structure is simple and compact. The entire optical path system is simpler and cheaper than laboratory-level large Raman instruments, thus realizing the fabrication of a low-cost, small-sized and multifunctional Raman spectrometer.

[0061] The above embodiments do not limit the optical path structure for each spectral detection mode. This application also provides corresponding optical path structures based on different spectral detection modes, which may include the following:

[0062] If the spectral detection mode is white light microscopy imaging observation mode, the corresponding single-mode detection system 3 includes a white light microscopy imaging observation sub-optical path system. This sub-optical path system may include a first lens 311, a first reflector 312, and an imaging device 313. When the objective lens 21 and the transmission-reflection functional element 22 in the light adjustment element group are located in the white light mode position region, they are connected. Specifically, the beam emitted from the white light source 12 passes through the first lens 311, the transmission-reflection functional element 22, and the objective lens 21 and is incident on the first sample to be tested in the sample detection cell 4. The reflected light from the first sample to be tested passes sequentially through the objective lens 21, the transmission-reflection functional element 22, and the first reflector 312 and is incident on the imaging device 313 to perform white light microscopy imaging observation on the first sample to be tested.

[0063] Furthermore, in order to improve the compactness of the entire optical path system, the light adjustment element group may also include a second reflector 23. Similarly, the second reflector 23 is also located in the white light mode position area. Correspondingly, the reflected light of the first sample under test passes through the objective lens 21, the transmission and reflection functional element 22, the second reflector 23, and the first reflector 312 in sequence and is incident on the imaging device 313 to perform white light microscopic imaging observation of the first sample under test.

[0064] If the spectral detection mode is absorption spectroscopy, Raman spectroscopy, or fluorescence spectroscopy, the light beam needs to be split. Accordingly, the single-mode detection system 3 may also include a spectrophotometer system. The spectrophotometer system includes a light propagation alteration element 321, a grating 322, a focusing element 323, and an image sensor 324. The incident light entering the spectrophotometer system passes sequentially through the light propagation alteration element 321, the grating 322, and the focusing element 323 before being projected onto the image sensor 324. The image sensor 324 performs imaging processing based on the received light signal.

[0065] In this embodiment, the light propagation changing element 321 is an optical component that can change the direction of light propagation, such as any type of lens or any type of concave mirror. The focusing element 323 is an optical component that can focus light to a specified position, such as any type of focusing lens or any type of concave mirror. Concave mirrors have better chromatic aberration performance than lenses; lenses have better aberration performance than concave mirrors. Those skilled in the art can flexibly choose the type of components used for the light propagation changing element 321 and the focusing element 323 according to the actual application scenario, and this application does not impose any limitations on this. The grating 322 includes a front and a back surface and can rotate. The front surface of the grating 322 is the light incident surface, and the back surface is the light exit surface. The grating 322 in this embodiment consists of a first grating and a second grating. The first and second gratings can be rotated according to the actual scenario to represent the front or back side in the current application scenario. The first and second gratings have different scribe line densities. For ease of description, the scribe line density of the first grating can be set to be less than that of the second grating; that is, the first grating is a low-scribe line surface, and the second grating is a high-scribe line surface. Besides the rotation of the front and back sides of the grating 322, the angle between the grating surface and the optical axis can also be adjusted. By changing the angle between the grating surface and the optical axis, the spectral detection requirements for specific functions can be met. The rotation of the grating surface of the grating 322 can be manual or automated. In manual rotation mode, a knob can be set at a corresponding position, and the user rotates the grating surface by operating the knob. In automated rotation mode, the grating 322 can be connected to a motor, and the rotation of the grating surface can be achieved by controlling the motor. Similarly, the angle adjustment of the grating 322 can be achieved manually or automatically. When rotating manually, both the groove and the positioning ball can be installed simultaneously to control the rotation angle. For automated rotation, the number of steps in the stepper motor can be used to control the rotation to a specified angle. For applications requiring high detection accuracy, a holographic grating can be used for the grating 322 to reduce stray noise. The image sensor 324 can be, for example, a CCD detector or a CMOS detector; those skilled in the art can choose flexibly according to the actual application scenario. To improve the accuracy of spectral detection, the cooling temperature of the CCD detector is set below -40 degrees Celsius, which can significantly reduce noise.

[0066] Furthermore, to make the optical path structure more compact and smaller in size, the above-mentioned spectrophotometer system may also include a sixth reflecting mirror 325. Accordingly, the incident light rays pass sequentially through the light propagation alteration element 321, the grating 322, the focusing element 323 and the sixth reflecting mirror 325 before being projected into the image sensor 324.

[0067] In this embodiment, if the user selects the absorption spectral detection mode, the corresponding single-mode detection system includes an absorption spectral detection sub-optical path system. The absorption spectral detection sub-optical path system may include a second lens 331, a third mirror 332, a fourth mirror 333, a third lens 334, a slit 335, and a spectrophotometer system. It is connected when the first grating of the rotating grating 322 is facing forward, and all optical elements of the light adjustment element group have moved to the absorption mode position region. After the optical path is connected, the beam emitted from the broadband light source 13 passes through the second lens 331 and the third mirror 332 and is incident on the second sample to be tested in the sample detection cell 4. The reflected light from the second sample to be tested sequentially passes through the fourth mirror 333, the third lens 334, and the slit 335 before entering the spectrophotometer system, thereby realizing the absorption spectrum detection of the second sample to be tested.

[0068] If the user selects Raman spectral detection mode, the corresponding single-mode detection system includes a Raman spectral detection sub-optical path system. The Raman spectral detection sub-optical path system may include a fourth reflecting mirror 333, a fifth reflecting mirror 341, a third lens 334, a slit 335, and a spectrophotometer system. In this system, the second grating of the rotating grating 322 is on the front, and the first long-pass filter 24 and the second long-pass filter 25 of the light adjustment element group are located on the optical axis. All other optical elements in the Raman spectral detection sub-optical path system are connected when they move to the Raman mode position region. Once the optical path is connected, the laser beam emitted from the laser source 11 passes through the fifth reflecting mirror 341, the first long-pass filter 24, and the objective lens 21 of the light adjustment element group and is incident on the third sample to be tested in the sample detection cell 4. The reflected light from the third sample to be tested passes sequentially through the objective lens 21, the first long-pass filter 24, the second long-pass filter 25, the fourth reflecting mirror 333, the third lens 334, and the slit 335 into the spectrophotometer system, thereby realizing the Raman spectrum detection of the third sample to be tested.

[0069] Furthermore, to improve the accuracy of Raman spectroscopy detection, the Raman spectroscopy detection sub-optical path system may also include a neutral density filter 342 and a laser beam expander 343. Accordingly, the laser beam emitted from the laser source 11 passes through the neutral density filter 342, the fifth reflecting mirror 341, the laser beam expander 343, the first long-pass filter 24, and the objective lens 21 and is incident on the third sample to be tested.

[0070] To further enhance the practicality of the Raman spectrometer and enable more functions, in Raman spectroscopy detection mode, while the grating 322 rotates to a high-notch number-density surface for Raman spectroscopy detection, the grating 322 can also employ multiple incident angle positions corresponding to different Raman frequency shift detection ranges to achieve full-spectrum Raman detection. In other words, this embodiment allows adjustment of the incident angle position of the grating 322 according to the Raman frequency shift detection range for Raman spectroscopy detection; wherein, the incident angle position is the angle between the front surface of the grating 322 and the optical axis of the Raman spectroscopy detection sub-optical path system.

[0071] If the user selects fluorescence spectral detection mode, the corresponding single-mode detection system includes a fluorescence spectral detection sub-optical path system. This sub-optical path system includes a fourth reflecting mirror 333, a fifth reflecting mirror 341, a third lens 334, a slit 335, and a spectrophotometer system. The fluorescence spectral detection sub-optical path system is connected when the grating 322 is rotated to the target position, and the first long-pass filter 24 and the second long-pass filter 25 of the light adjustment element group are located on the optical axis of the fluorescence spectral detection sub-optical path system, and all other optical elements in the system have moved to the fluorescence mode position area. In this embodiment, the target position is the front face of the grating 322 and the angle between the grating 322 and the optical axis, determined according to the current detection wavelength. Once the optical path is connected, the laser beam emitted from the laser source 11 passes through the fifth reflecting mirror 341, the first long-pass filter 24, and the objective lens 21 of the light adjustment element group and is incident on the fourth sample to be tested in the sample detection cell 4. The reflected light from the fourth sample to be tested passes sequentially through the objective lens 21, the first long-pass filter 24, the second long-pass filter 25, the fourth reflecting mirror 333, the third lens 334, and the slit 335 into the spectrophotometer system, and performs fluorescence spectral detection on the fourth sample to be tested in different wavelength bands.

[0072] Furthermore, to improve the accuracy of fluorescence spectroscopy detection, the fluorescence spectroscopy detection sub-optical path system may also include a neutral density filter 342 and a laser beam expander 343. Accordingly, the laser beam emitted from the laser source 11 passes through the neutral density filter 342, the fifth reflecting mirror 341, the laser beam expander 343, the first long-pass filter 24, and the objective lens 21 and is incident on the fourth sample to be tested.

[0073] The terms "first sample to be tested," "second sample to be tested," "third sample to be tested," and "fourth sample to be tested" are merely to indicate samples detected under different spectral detection modes. The first sample to be tested, the second sample to be tested, the third sample to be tested, and the fourth sample to be tested can be the same sample or different samples, which does not affect the implementation of this application.

[0074] To enable those skilled in the art to better understand the technical solution of this application, this application also incorporates... Figures 2 to 6 A schematic example is given in this embodiment. The Raman spectrometer achieves white light microscopic imaging, Raman spectroscopy detection, absorption spectroscopy detection, and fluorescence spectroscopy detection functions by rotating or switching the grating surface and moving the positions of the optical elements in the light-adjusting element group. Specifically, the transmission / reflection element 22 is a semi-transparent mirror, the light propagation alteration element 321 is a lens, the focusing element 323 is a focusing lens, the grating 322 is a holographic grating, the image sensor 324 is a CCD detector with a cooling temperature set below -40 degrees Celsius, and the imaging device 313 is a camera. Figure 2As shown, the light source system 1 includes a laser light source 11, a white light source 12, and a broadband light source 13. The light adjustment element group may include an objective lens 21, a semi-transparent mirror 22, a second mirror 23, a first long-pass filter 24, and a second long-pass filter 25. The multi-mode switching system 2 is pre-set with a moving switching platform 20, which includes a first position area 201, a second position area 202, a third position area 203, and a default position area 204. The light adjustment element group is in the default position area 204 by default. Switching between different spectral detection modes is achieved by moving the relevant optical elements of the light adjustment element group into the first position area 201, the second position area 202, and the third position area 203. The spectrophotometer system includes a lens 321, a grating 322, a focusing lens 323, a sixth mirror 325, and a CCD detector 324. The sample detection cell 4 is placed on the three-dimensional moving platform 5. This embodiment may include the following:

[0075] like Figure 3 As shown, if the current spectral detection mode is white light microscopy imaging observation mode, the corresponding optical path is as follows: the beam emitted by the white light source 12 passes sequentially through the first lens 311, the semi-transparent mirror 22, the objective lens 21, the sample detection cell 4, the objective lens 21, the semi-transparent mirror 22, the second mirror 23, the first mirror 312, and the camera 313. The specific detection process of achieving microscopic imaging of solid samples using the white light microscopy system includes: turning on the white light source 12, the white light beam being focused onto the solid sample through the semi-transparent mirror 22 and the objective lens 21, focusing the solid sample by operating the three-dimensional moving platform 5, and the objective lens 21 collecting the reflected light from the solid sample and entering the camera 313 to achieve white light microscopy imaging observation.

[0076] like Figure 4As shown, if the current spectral detection mode is absorption spectral detection mode, the corresponding optical path is as follows: the beam emitted by the broadband light source 13 passes sequentially through the second lens 331, the third reflector 332, the sample detection cell 4, the fourth reflector 333, the third lens 334, the slit 335, and the spectrophotometer system; simultaneously, the optical elements on the moving switching platform 20 are slid to the positions of the first position area 201, the second position area 202, and the third position area 203, deviating from the optical path in the default mode; the grating 322 is rotated to the low-scratching surface to achieve broadband absorption spectral detection. The specific detection process is as follows: the broadband light source 13 is activated, and after the beam passes through the second lens 331 and the third reflector 332, it illuminates the transparent sample. The objective lens 21 collects the absorption spectral signal, and after the stray light is filtered out by the slit 335 and the beam is dispersed by the grating 322, the absorption spectrum is unfolded on the CCD detector 324. In this embodiment, when the angle between the low-density grating surface (150 G / mm) and the optical axis is approximately 63.5°, the wavelength range detectable by the CCD detector 324 is 400 nm to 1000 nm. The absorption spectrum can be obtained by subtracting the light source response curve obtained by placing a blank cuvette from the projection response curve obtained by adding the sample to the cuvette.

[0077] like Figure 5As shown, if the current spectral detection mode is Raman spectral detection mode, the corresponding optical path is as follows: the laser emitted by the laser source 11 passes sequentially through the neutral density filter 342, the fifth reflecting mirror 341, the laser beam expander 343, the first long-pass filter 24, the objective lens 21, the sample detection cell 4, the objective lens 21, the first long-pass filter 24, the second long-pass filter 25, the fourth reflecting mirror 333, the third lens 334, the slit 335, and the spectrophotometer system; at the same time, only the first long-pass filter 24 and the second long-pass filter 25 are kept on the optical axis on the moving switching platform 20, and the remaining optical elements are moved to the first position area 201 and the second position area 202; the grating 322 is rotated to the high-dent number density surface to realize Raman spectral detection. The specific detection process is as follows: For solid samples, after determining the sample position using white light microscopy, the laser source 11 (e.g., a laser with a wavelength of 532 nm) is turned on. The beam passes through the lens used for beam expansion before the laser source 11, i.e., the laser beam expander 343, and then through two long-pass filters before being focused onto the sample surface by the objective lens 21, exciting the sample and generating a Raman scattering signal. The Raman scattering signal collected by the objective lens 21 is filtered by the slit 335 and dispersed by the grating 322, and then focused by the focusing lens 323 onto the CCD detector 324, detecting the Raman spectral signal. For liquid samples, the acquisition method is similar to that for solid samples. Furthermore, by rotating the grating 322, when the angle between the 1200 G / mm high-density grating surface and the optical axis is approximately 45°, the spectral range of 530 nm to 610 nm can be detected; by rotating the grating 322 so that the angle between the grating surface and the optical axis is approximately 48°, the spectral range of 590 nm to 680 nm can be detected.

[0078] like Figure 6As shown, the current spectral detection mode is fluorescence spectral detection mode, and the corresponding optical path is as follows: the laser emitted by the laser source 11 passes sequentially through the neutral density filter 342, the fifth reflecting mirror 341, the laser beam expander 343, the first long-pass filter 24, the objective lens 21, the sample detection cell 4, the objective lens 21, the first long-pass filter 24, the second long-pass filter 25, the fourth reflecting mirror 333, the third lens 334, the slit 335, and the spectrophotometer system; at this time, only the first long-pass filter 24 and the second long-pass filter 25 are kept on the optical axis on the moving switching platform 20, and the remaining optical elements are moved to the first position area 201 and the second position area 202; the grating 322 is rotated to different surfaces and different angles to achieve fluorescence spectral detection requirements of different wavelengths. The specific detection process is as follows: For solid samples, the sample position is first determined using a white light microscope system. Then, the laser source 11 is turned on. The beam passes through the lens (laser beam expander 343) in front of the laser source 11, and then through two long-pass filters before being focused onto the sample surface by the objective lens 21, exciting the sample and generating a fluorescence signal. The fluorescence signal collected by the objective lens 21 is filtered by the slit 335 and dispersed by the grating 322, and then focused by the focusing lens 323 onto the CCD detector 324, detecting the fluorescence spectrum signal. For liquid samples, the acquisition method is similar to that for solid samples. When the grating 322 is rotated so that the angle between the 150 G / mm grating surface and the optical axis is approximately 63.5°, the wavelength range detectable by the CCD detector 324 is 400 nm to 1000 nm. Rotating grating 322 so that the angle between the 1200G / mm grating surface and the optical axis is approximately 45° enables detection in the spectral range of 530nm-610nm; rotating grating 322 so that the angle between the 1200G / mm grating surface and the optical axis is approximately 48° enables detection in the spectral range of 590nm-680nm.

[0079] As can be seen from the above, compared to portable Raman instrument optical systems, the Raman spectrometer provided in this embodiment can meet various spectral detection needs and satisfy the sensitivity and spectral resolution required for research-level spectral detection. The entire optical path system is simpler than that of large laboratory-grade Raman instruments, while still possessing multifunctional spectral detection capabilities and a compact size. Except for some components that require movement or rotation for switching, the remaining optical components are all fixed. Optical components and instrument modules are commercially available at low prices, resulting in a lower overall cost for the optical system.

[0080] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the hardware disclosed in the embodiments, including devices and electronic equipment, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0081] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0082] The Raman spectrometer provided in this application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the invention. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of the invention. It should be noted that those skilled in the art can make various improvements and modifications to this application without departing from the principles of the invention, and these improvements and modifications also fall within the protection scope of the claims of this application.

Claims

1. A Raman spectrometer, characterized in that, This includes a light source system, a multi-mode switching system, and a single-mode detection system; The light source system includes multiple types of light sources suitable for different spectral detection modes; The multi-mode switching system includes a mobile switching platform with multiple mode position areas and a light adjustment element group, each mode position area corresponding to a spectral detection mode; it is used to connect the sub-optical path system in the corresponding spectral detection mode by moving each optical element in the light adjustment element group to the corresponding mode position area; the light adjustment element group includes an objective lens, a transmission and reflection functional element, a first long-pass filter and a second long-pass filter; The single-mode detection system includes multiple sub-optical path systems, each of which corresponds to a spectral detection mode. Raman spectrometers achieve white light microscopy imaging, Raman spectroscopy detection, absorption spectroscopy detection, and fluorescence spectroscopy detection functions by rotating or switching the grating surface and moving the positions of the optical elements in the light adjustment element group. The light adjustment element group is located in the default mode position area corresponding to the white light microscopy imaging observation mode. If the current spectral detection mode is absorption spectroscopy detection mode, the optical elements on the switching platform are slid to the positions of the first mode position area, the second mode position area, and the third mode position area, and the grating is rotated to a low-scratch-number surface to achieve broad-spectrum absorption spectroscopy detection; if the current spectral detection mode is... In the Raman spectroscopy detection mode, only the first and second long-pass filters on the optical axis are kept on the moving switching platform. The remaining optical elements are moved to the first and second mode position areas, and the grating is rotated to the high-notch number density surface to achieve Raman spectroscopy detection. The current spectral detection mode is the fluorescence spectroscopy detection mode. In this mode, only the first and second long-pass filters on the optical axis are kept on the moving switching platform. The remaining optical elements are moved to the first and second mode position areas, and the grating is rotated to different surfaces and angles to meet the fluorescence spectroscopy detection requirements of different wavelengths.

2. The Raman spectrometer according to claim 1, characterized in that, The light source system includes a laser light source and / or a white light source and / or a broadband light source; The laser source is used to emit a laser beam as a light source in both Raman spectroscopy detection mode and fluorescence spectroscopy detection mode. The white light source serves as the light source for the white light microscopic imaging observation mode; The broadband light source is used as the light source in the absorption spectroscopy detection mode.

3. The Raman spectrometer according to claim 2, characterized in that, The spectral detection mode is a white light microscopy imaging observation mode, and the single-mode detection system includes a white light microscopy imaging observation sub-optical path system. The white light microscopy imaging observation sub-optical path system includes a first lens, a first reflector, and an imaging device. The objective lens and the transmission-reflection functional element in the light adjustment element group are connected when they are in the white light mode position region. The white light source emitted beam passes through the first lens, the transmission-reflection functional element, and the objective lens and is incident on the first sample to be tested in the sample detection cell. The reflected light from the first sample to be tested passes through the objective lens, the transmission-reflection functional element, and the first reflector in sequence and is incident on the imaging device to perform white light microscopy imaging observation on the first sample to be tested.

4. The Raman spectrometer according to claim 3, characterized in that, The light adjustment element group further includes a second reflector; the second reflector is located in the white light mode position area; The reflected light from the first sample under test passes sequentially through the objective lens, the transmission and reflection functional element, the second reflector, and the first reflector before entering the imaging device to perform white light microscopic imaging observation of the first sample under test.

5. The Raman spectrometer according to claim 2, characterized in that, The spectral detection mode is an absorption spectral detection mode, a Raman spectral detection mode, or a fluorescence spectral detection mode, and the single-mode detection system also includes a spectrophotometric measurement system; The spectrophotometer includes a light propagation alteration element, a grating, a focusing element, and an image sensor; the incident light rays pass sequentially through the light propagation alteration element, the grating, and the focusing element before being projected onto the image sensor. The grating includes a first grating and a second grating with different scribe number densities on their front and back sides, wherein the scribe number density of the first grating is less than that of the second grating.

6. The Raman spectrometer according to claim 5, characterized in that, The spectral detection mode is an absorption spectral detection mode, and the single-mode detection system includes an absorption spectral detection sub-optical path system. The absorption spectral detection sub-optical path system includes a second lens, a third mirror, a fourth mirror, a slit, and the spectrophotometer system. When the first grating of the grating is rotated to face the front, and all optical elements of the light adjustment element group are moved to the absorption mode position region, they are connected. The broadband light source emits a beam that passes through the second lens and the third reflector and is incident on the second sample to be tested in the sample detection cell. The reflected light from the second sample to be tested passes through the fourth reflector, the third lens, and the slit in sequence and enters the spectrophotometer to perform absorption spectrum detection on the second sample to be tested.

7. The Raman spectrometer according to claim 5, characterized in that, The spectral detection mode is Raman spectral detection mode, and the single-mode detection system includes a Raman spectral detection sub-optical path system. The Raman spectroscopy detection sub-optical path system includes a fourth mirror, a fifth mirror, a third lens, a slit, and the spectrometer system. When the second grating of the grating is rotated to face the front, and the first long-pass filter and the second long-pass filter of the light adjustment element group are located on the optical axis, all other optical elements in the Raman spectroscopy detection sub-optical path system are connected when they move to the Raman mode position region. The laser beam emitted from the laser source passes through the fifth reflecting mirror, the first long-pass filter, and the objective lens of the light adjustment element group and is incident on the third sample to be tested in the sample detection cell. The reflected light from the third sample to be tested passes sequentially through the objective lens, the first long-pass filter, the second long-pass filter, the fourth reflecting mirror, the third lens, and the slit into the spectrophotometer system to perform Raman spectroscopy detection on the third sample to be tested.

8. The Raman spectrometer according to claim 7, characterized in that, The Raman spectroscopy detection sub-optical path system also includes a neutral density filter and a laser beam expander; The laser beam emitted from the laser source passes through the neutral density filter, the fifth reflecting mirror, the laser beam expander, the first long-pass filter, and the objective lens and is incident on the third sample to be tested.

9. The Raman spectrometer according to claim 7, characterized in that, The incident angle position of the grating is adjusted according to the Raman frequency shift detection range to perform Raman spectroscopy detection; The incident angle is the angle between the front of the grating and the optical axis of the Raman spectroscopy detection sub-optical path system.

10. The Raman spectrometer according to claim 5, characterized in that, The spectral detection mode is a fluorescence spectral detection mode, and the single-mode detection system includes a fluorescence spectral detection sub-optical path system; The fluorescence spectroscopy detection sub-optical path system includes a fourth mirror, a fifth mirror, a third lens, a slit, and the spectrophotometer system. When the grating is rotated to the target position, and the first and second long-pass filters of the light adjustment element group are located on the optical axis, all other optical elements in the fluorescence spectroscopy detection sub-optical path system are connected when they have moved to the fluorescence mode position region. The target position is the front face of the grating and the angle between the grating and the optical axis, determined according to the current detection wavelength. The laser beam emitted from the laser source passes through the fifth reflecting mirror, the first long-pass filter, and the objective lens of the light adjustment element group, and is incident on the fourth sample to be tested in the sample detection cell. The reflected light from the fourth sample to be tested passes sequentially through the objective lens, the first long-pass filter, the second long-pass filter, the fourth reflecting mirror, the third lens, and the slit into the spectrophotometer system to perform fluorescence spectral detection on the fourth sample to be tested in different wavelength bands.

11. The Raman spectrometer according to claim 10, characterized in that, The fluorescence spectroscopy detection sub-optical path system also includes a neutral density filter and a laser beam expander; The laser beam emitted from the laser source passes through the neutral density filter, the fifth reflecting mirror, the laser beam expander, the first long-pass filter, and the objective lens and is incident on the fourth sample to be tested.

12. The Raman spectrometer according to claim 5, characterized in that, The spectrophotometer system also includes a sixth reflector; the incident light rays pass sequentially through the light propagation alteration element, the grating, the focusing element, and the sixth reflector before being projected onto the image sensor.

13. The Raman spectrometer according to any one of claims 1 to 12, characterized in that, It also includes a 3D mobile platform; The three-dimensional moving platform is used to carry the sample detection cell and moves the sample to the detection position by controlling the movement distance on the X, Y and Z axes.

14. The Raman spectrometer according to claim 13, characterized in that, The sample detection cell also holds a cuvette or a glass slide.

Images