Dual-wavelength Raman probe and Raman spectrometer

Abstract

The present application relates to Raman spectroscopy technology, specifically disclosing a dual-wavelength Raman probe and a Raman spectrometer. The dual-wavelength Raman probe includes a first laser module, a second laser module, a dual-wavelength acquisition module, and a Raman filter module. The first laser module includes a first dichroic mirror, the second laser module includes a second dichroic mirror, the dual-wavelength acquisition module includes a third dichroic mirror and a third lens, and the Raman filter module includes a fourth dichroic mirror and a fourth lens. The dual-wavelength laser beam passes through the first laser module, the second laser module, and the dual-wavelength acquisition module, and the two Raman signals scattered after irradiating the sample are ultimately focused through the Raman filter module onto the same external spectrometer for Raman signal analysis. The Raman channels can be integrated into a single spectral channel, and the dual-wavelength Raman signal can be collected through the single spectral channel without the need for two spectrometers.

Description

Technical Field

[0001] The present application relates to Raman spectroscopy technology, and in particular to a dual-wavelength Raman probe and a Raman spectrometer. Background Art

[0002] A dual-wavelength Raman probe is a spectral detection device that combines two different excitation wavelengths. Its core design uses Raman scattering to obtain information about the sample's molecular vibrations by synchronously or alternately exciting the sample. The operating principle of a dual-wavelength Raman probe involves two different laser wavelengths, typically emitted by two different lasers. A common wavelength combination is 532nm for visible light and 785nm for near-infrared light. The laser beams are introduced into the probe via an optical fiber and focused onto the sample. Molecules in the sample interact with the laser light, causing Raman scattering. The Raman signals from the two wavelengths are collected separately and analyzed by a spectrometer.

[0003] Existing technologies use dual excitation wavelengths and dual Raman signal acquisition channels, requiring two spectrometers with corresponding excitation wavelengths, resulting in high costs and complex equipment. For example, existing technologies disclose a dual-wavelength laser confocal Raman probe and a Raman spectrometer. The Raman spectrometer includes: a dual-wavelength laser confocal Raman probe; a laser module including a first laser connected to the first laser module via a first laser transmission fiber and a second laser connected to the second laser module via a second laser transmission fiber; and a spectrum analysis module including a first spectrometer connected to the first laser module via a first Raman transmission fiber and a second spectrometer connected to the second laser module via a second Raman transmission fiber.

[0004] The aforementioned Raman probe and Raman spectrometer can use two laser wavelengths to perform confocal Raman excitation on the sample under test, and collect and spectrally analyze the two wavelengths of Raman scattered light emitted by the sample. However, the device still requires a first spectrometer and a second spectrometer to match the first and second lasers. In other words, this technical solution still uses two Raman channels, and the detector cost needs to be further reduced. In addition, it requires simultaneous control of the two spectrometers and splicing of the collected data from the two spectrometers, which requires complex equipment operation. Therefore, there is a need for further improvements to reduce equipment costs and simplify equipment and operation. Summary of the Invention

[0005] To address the high cost associated with using two Raman channels, the present application provides a dual-wavelength Raman probe that integrates the two Raman channels into one Raman channel. Based on the dual-wavelength Raman probe, the present application also provides a Raman spectrometer.

[0006] This application provides a dual-wavelength Raman probe, which adopts the following technical solution:

[0007] A dual-wavelength Raman probe includes a first laser module, a second laser module, a dual-wavelength acquisition module, and a Raman filter module. The first laser module includes a first dichroic mirror, which is used to reflect a laser beam of a first preset wavelength and transmit a Raman signal of the first preset wavelength. The second laser module includes a second dichroic mirror, which is used to reflect a laser beam of a second preset wavelength and transmit a Raman signal of the second preset wavelength.

[0008] The dual-wavelength acquisition module includes a third dichroic mirror and a third lens. The third dichroic mirror is located on one side of the first dichroic mirror and on one side of the second dichroic mirror. The third dichroic mirror is used to transmit the first preset wavelength laser beam and the first preset wavelength Raman signal respectively, and reflect the second preset wavelength laser beam and the second preset wavelength Raman signal respectively. The third lens is located on the side of the third dichroic mirror away from the first dichroic mirror or the second dichroic mirror and focuses the first preset wavelength laser beam and the second preset wavelength laser beam respectively. The third lens collimates the first preset wavelength Raman signal and the second preset wavelength Raman signal respectively.

[0009] The Raman filter module includes a fourth dichroic mirror and a fourth lens. The fourth dichroic mirror is located on the other side of the first dichroic mirror and on the other side of the second dichroic mirror. The fourth dichroic mirror is used to reflect the first preset wavelength Raman signal and transmit the second preset wavelength Raman signal. The fourth lens is located on the side of the fourth dichroic mirror away from the first dichroic mirror or the second dichroic mirror and focuses the first preset wavelength Raman signal and the second preset wavelength Raman signal, respectively.

[0010] By adopting the above technical solution, its working principle is as follows: the first preset wavelength laser beam and the second preset wavelength laser beam are output by two external laser light sources respectively, and the first dichroic mirror is arranged on the emission path of the first preset wavelength laser beam, and the first preset wavelength laser beam is reflected by the first dichroic mirror to the third dichroic mirror, and then transmitted to the third lens through the third dichroic mirror, and is focused by the third lens and irradiated onto the sample to be tested, thereby forming a complete emission path channel of the first preset wavelength laser beam. Similarly, the second dichroic mirror is arranged on the emission path of the second preset wavelength laser beam, and the second preset wavelength laser beam is reflected by the second dichroic mirror to the third dichroic mirror, and then reflected by the third dichroic mirror to the third lens, and is focused by the third lens and irradiated onto the sample to be tested, thereby forming a complete emission path channel of the second preset wavelength laser beam.

[0011] The above-mentioned first preset wavelength laser beam is focused and irradiated onto the surface of the sample to be measured. The first preset wavelength Raman signal scattered by the interaction between the laser and the molecules of the sample is collimated by the third lens. The collimated first preset wavelength Raman signal is transmitted through the third dichroic mirror and the first dichroic mirror in sequence, and then irradiated onto the fourth dichroic mirror. After being focused by the fourth lens, it is connected to the external spectrometer signal, thereby forming a complete Raman signal collection channel for the first preset wavelength laser beam.

[0012] The above-mentioned second preset wavelength laser beam is focused and irradiated onto the surface of the sample to be measured. The second preset wavelength Raman signal scattered by the interaction between the laser and the molecules of the sample is collimated by the third lens. The collimated second preset wavelength Raman signal is reflected by the third dichroic mirror, transmitted by the second dichroic mirror, and then projected onto the fourth dichroic mirror. After that, it is focused by the fourth lens and connected to the external spectrometer signal, thereby forming a complete Raman signal collection channel for the second preset wavelength laser beam.

[0013] According to the above principle, under the dual-wavelength laser excitation of the first preset wavelength laser beam and the second preset wavelength laser beam, the first preset wavelength laser beam passes through the first laser module and the dual-wavelength acquisition module, and the Raman signal scattered after irradiating the sample (i.e., the first preset wavelength Raman signal) is finally focused through the Raman filter module to an external spectrometer for Raman signal analysis. At the same time, the second preset wavelength laser beam passes through the second laser module and the dual-wavelength acquisition module, and the other Raman signal scattered after irradiating the sample (i.e., the second preset wavelength Raman signal) is finally focused through the Raman filter module to the same external spectrometer for Raman signal analysis. Therefore, the present application can integrate the Raman channels into a single spectral channel, and the collection of dual-wavelength Raman signals can be achieved through the single spectral channel.

[0014] Preferably, the first laser module further includes a first lens, and the second laser module further includes a second lens, the first lens and the second lens are respectively collimating lenses, the first preset wavelength laser beam is emitted toward one side of the first dichroic mirror via the first lens, and the second preset wavelength laser beam is emitted toward one side of the second dichroic mirror via the second lens.

[0015] By adopting the above technical solution, as a specific structural example, by setting the above-mentioned first lens and second lens, the first preset wavelength laser beam and the second preset wavelength laser beam are collimated respectively.

[0016] Preferably, the first laser module further includes a first reflector, and the first reflector is used to reflect the laser beam of the first preset wavelength so that the laser beam of the first preset wavelength is emitted toward one side of the first dichroic mirror.

[0017] By adopting the above technical solution, as a structural example, the direction of the laser light is changed by the above first reflector. More specifically, the first reflector is a plane reflector, and the angle of the first reflector can be adjusted according to actual needs.

[0018] Preferably, the first laser module further includes a first filter having a transmission wavelength consistent with the first preset wavelength laser beam, and the first preset wavelength laser beam is emitted to one side of the first dichroic mirror via the first filter.

[0019] By adopting the above technical solution, as an exemplary structure, a first filter is provided whose transmission wavelength matches the first preset wavelength of the laser beam. After the light beam passes through the first filter, laser light with a wavelength equal to the first preset wavelength is selected, thereby filtering out unwanted wavelengths. More specifically, the angle of the first filter is preferably perpendicular or nearly perpendicular to the direction of the light beam emission, for example, at a 180° angle relative to the first lens, to ensure a good filtering effect. The first filter can be a laser line filter.

[0020] Preferably, the second laser module further includes a second reflector and / or a third reflector, the second reflector being used to reflect the laser beam of a second preset wavelength so that the laser beam of the second preset wavelength is emitted toward one side of the second dichroic mirror; the third reflector being used to respectively reflect the laser beam of the second preset wavelength and the Raman signal of the second preset wavelength so that the laser beam of the second preset wavelength is emitted toward the other side of the third dichroic mirror, and the Raman signal of the second preset wavelength is emitted toward one side of the second dichroic mirror.

[0021] By adopting the above technical solution, as a structural example, the second and third reflectors are used to change the direction of the laser light. More specifically, the second and third reflectors are both plane reflectors, and the angles of the second and third reflectors can be adjusted according to actual needs.

[0022] Preferably, the second laser module further includes a second filter having a transmission wavelength consistent with the second preset wavelength laser beam, and the second preset wavelength laser beam is emitted to one side of the second dichroic mirror through the second filter.

[0023] By adopting the above technical solution, as one structural example, a second filter is provided whose transmission wavelength matches the second preset wavelength laser beam. After the light beam passes through the second filter, laser light with a wavelength equal to the second preset wavelength laser beam is selected, thereby filtering out unwanted wavelengths. More specifically, the angle of the second filter is preferably perpendicular or nearly perpendicular to the direction of the light beam emission, for example, at a 180° angle relative to the second lens, to ensure a good filtering effect. The second filter can be a laser line filter.

[0024] Preferably, the Raman filter module further includes a fourth reflector, a third filter having a cutoff wavelength consistent with the first preset wavelength Raman signal, and a fourth filter having a cutoff wavelength consistent with the second preset wavelength Raman signal. The fourth reflector is located on the other side of the first dichroic mirror. The fourth reflector is used to reflect the first preset wavelength Raman signal so that the first preset wavelength Raman signal is emitted toward a side of the fourth dichroic mirror away from the first dichroic mirror or the second dichroic mirror; the third filter and the fourth filter are respectively long-pass filters, and the first preset wavelength Raman signal is emitted to one side of the fourth dichroic mirror via the third filter, and the second preset wavelength Raman signal is emitted to the other side of the fourth dichroic mirror via the fourth filter.

[0025] By adopting the above technical solution, as a structural example, the emission direction of the Raman signal is changed by the fourth reflector. More specifically, the fourth reflector is a plane reflector, and the angle of the fourth reflector can be adjusted according to actual needs.

[0026] A third filter with a cutoff wavelength that matches the Raman signal of the first preset wavelength and a fourth filter with a cutoff wavelength that matches the Raman signal of the second preset wavelength are provided. After the light beam passes through the third filter, the laser signal in the Raman signal of the first preset wavelength is filtered out, while the Raman signal is retained. Similarly, after the light beam passes through the fourth filter, the laser signal in the Raman signal of the second preset wavelength is filtered out, while the Raman signal is retained. More specifically, the angles of the third and fourth filters can be adjusted according to actual needs, preferably being perpendicular or nearly perpendicular to the direction of the light beam emission.

[0027] The present application also provides a Raman spectrometer, comprising the above-mentioned dual-wavelength Raman probe.

[0028] By adopting the above technical solution and applying the above dual-wavelength Raman probe to a Raman spectrometer, the equipment cost can be reduced and the operation is convenient.

[0029] Preferably, it further includes a first laser light source and a second laser light source, wherein the first laser light source is connected to the first laser module signal through a transmission optical fiber, and the second laser light source is connected to the second laser module signal through a transmission optical fiber.

[0030] By adopting the above technical solution, as an example structure, a first laser light source provides a laser beam of a first preset wavelength, for example, a conventional 532nm laser; a second laser light source provides the first preset wavelength laser beam and a second preset wavelength laser beam, for example, a conventional 785nm laser. The first laser light source and the second laser light source are respectively connected to the first laser module and the second laser module via transmission optical fibers.

[0031] Preferably, it further comprises a spectrometer, which is connected to the fourth lens signal via a transmission optical fiber.

[0032] By adopting the above technical solution, as a structural example, a spectrometer is set up and connected to the fourth lens signal through a transmission optical fiber. The Raman signals in the fifth reflected light beam and the fifth transmitted light beam after being focused by the fourth lens are input into the spectrometer through the transmission optical fiber, thereby completing the spectral analysis.

[0033] In summary, this application has at least the following beneficial effects:

[0034] The dual-wavelength Raman probe of this application can integrate Raman channels into a single spectral channel, allowing the collection of dual-wavelength Raman signals through a single spectral channel. The Raman spectrometer of this application only requires a single spectrometer to analyze the dual-wavelength Raman signals. Therefore, this application has the advantages of reducing costs, simplifying the overall equipment size, and simplifying equipment operation requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic diagram of a Raman spectrometer according to an embodiment of the present application;

[0036] Figure 2 Schematic diagram of the dual-wavelength Raman probe according to an embodiment of the present application.

[0037] Description of labels:

[0038] 11. First dichroic mirror; 12. First lens; 13. First reflector; 14. First filter;

[0039] 21. Second dichroic mirror; 22. Second reflector; 23. Third reflector; 24. Second filter; 25. Second lens;

[0040] 31. Third dichroic mirror; 32. Third lens;

[0041] 41. Fourth dichroic mirror; 42. Fourth lens; 43. Fourth reflector; 44. Third filter; 45. Fourth filter;

[0042] 5. First laser light source; 6. Second laser light source; 7. Spectrometer; 8. Transmission optical fiber. DETAILED DESCRIPTION

[0043] Although the present application can be easily embodied in different forms of embodiments, only some of the specific embodiments are shown in the drawings and will be described in detail in this specification. It should be understood that this description should be regarded as an exemplary illustration of the principles of the application and is not intended to limit the application to what is described herein.

[0044] Thus, a feature indicated in this specification will be used to illustrate one of the features of an embodiment of the present application, rather than implying that each embodiment of the present application must have the described feature. In addition, it should be noted that this specification describes many features. Although certain features can be combined together to illustrate possible system designs, these features can also be used in other, not explicitly described, combinations. Thus, unless otherwise stated, the described combinations are not intended to be limiting.

[0045] In the embodiments shown in the accompanying drawings, directional indications (such as up, down, left, right, front, and back) used to explain the structure and movement of various components of the present application are not absolute but relative. These descriptions are applicable when these components are in the positions shown in the accompanying drawings. If the descriptions of the positions of these components are changed, these directional indications will also change accordingly.

[0046] The present application is further described in detail below with reference to the accompanying drawings and examples.

[0047] Example 1

[0048] According to one embodiment of the present invention, reference can be made to Figure 1-2 , wherein like reference numerals denote corresponding components throughout the figures. It should be understood that the dual-wavelength Raman probe and Raman spectrometer according to the present application can be applied to the collection and analysis of all dual-wavelength Raman signals, as well as the collection and analysis of multi-wavelength Raman signals based on the concept of the present application.

[0049] For the convenience of description, given that the dichroic mirror has two sides in opposite directions, one side of the first dichroic mirror, one side of the second dichroic mirror, one side of the third dichroic mirror, one side of the fourth dichroic mirror, and the other side of the first dichroic mirror, the other side of the second dichroic mirror, the other side of the third dichroic mirror, and the other side of the fourth dichroic mirror are used to describe the two relative directions of the first dichroic mirror, the second dichroic mirror, the third dichroic mirror, and the fourth dichroic mirror, respectively.

[0050] like Figure 1-2 As shown, the dual-wavelength Raman probe of this embodiment includes: a first laser module, a second laser module, a dual-wavelength acquisition module and a Raman filter module.

[0051] In this embodiment, as a specific example, the first preset wavelength laser beam is selected as a laser with a wavelength of 532 nm, and the second preset wavelength laser beam is selected as a laser with a wavelength of 785 nm. The first preset wavelength Raman signal corresponds to a 532 nm Raman signal, and the second preset wavelength Raman signal corresponds to a 785 nm Raman signal.

[0052] See also Figure 1 and Figure 2The first laser module includes a first dichroic mirror 11, a first lens 12, a first reflector 13, and a first filter 14. The first lens 12, the first filter 14, the first reflector 13, and the first dichroic mirror 11 are sequentially arranged along the beam transmission direction and are coaxially arranged. An external laser outputs 532nm laser light to the first lens 12 via a transmission fiber. The first lens 12 is a collimating lens, used to collimate the laser light. The first filter 14 is a 532nm laser line filter, positioned 180° from the first lens 12. It selects 532nm laser light and filters out unwanted wavelengths. The first reflector 13 is a plane mirror, positioned 45° from the first filter 14. It reflects the laser light toward one side of the first dichroic mirror 11 (i.e., to the right of the first dichroic mirror 11 in the figure). The first dichroic mirror 11 is 180° away from the first reflector 13 and is used to reflect the 532 nm laser and transmit the 532 nm Raman signal.

[0053] The second laser module includes a second dichroic mirror 21, a second lens 25, a second reflector 22, a third reflector 23, and a second filter 24. The second lens 25, the second filter 24, the second reflector 22, the second dichroic mirror 21, and the third reflector 23 are arranged in sequence along the beam transmission direction. The second lens 25, the second filter 24, and the second reflector 22 are coaxially arranged. An external laser outputs 785nm laser light via a transmission fiber to the second lens 25, which is a collimating lens used to collimate the laser light. The second filter 24 is a 785nm laser line filter, which is 180° away from the first lens 12 and is used to select laser light with a wavelength of 785nm and filter out unwanted wavelengths; the second reflector 22 is a plane reflector, which is 45° away from the second filter and is used to reflect the laser light so that the laser light is emitted toward one side of the second dichroic mirror 21 (i.e., the right side of the second dichroic mirror in the figure); the second dichroic mirror 21 is 180° away from the second reflector 22 and is used to reflect the 785nm laser light. 5nm laser and transmits 785nm Raman signal; the third reflecting mirror 23 is a plane reflecting mirror, which is 180° to the third dichroic mirror 31 and is used to reflect 785nm laser and 785nm Raman signal, so that the 785nm laser is emitted toward the other side of the third dichroic mirror 31 (that is, the right side of the third dichroic mirror 31 in the figure), and at the same time, the 785nm Raman signal is emitted toward one side of the second dichroic mirror 21 (that is, the right side of the second dichroic mirror 21 in the figure).

[0054] The dual-wavelength acquisition module includes a coaxially arranged third dichroic mirror 31 and a third lens 32. The third dichroic mirror 31 is located on one side of the first dichroic mirror 11 (to the right of the first dichroic mirror 11 in the figure) and on the other side of the second dichroic mirror 21 (to the right of the second dichroic mirror 21 in the figure). The third dichroic mirror 31 is at a 90-degree angle to the first dichroic mirror 11 and is configured to transmit 532nm laser light and 532nm Raman signals, respectively, and reflect 785nm laser light and 785nm Raman signals, respectively. The third lens 32 is located on the side of the third dichroic mirror 31 away from the first dichroic mirror 11 or the second dichroic mirror 21 (i.e., to the right of the third dichroic mirror in the figure) and focuses the laser light. The laser light is focused onto the sample surface by the third lens 32, and the Raman signal scattered by the interaction between the laser light and the sample molecules is then collimated by the third lens 32.

[0055] The Raman filter module includes a fourth dichroic mirror 41, a fourth lens 42, a fourth reflector 43, a third filter 44, and a fourth filter 45. The fourth dichroic mirror 41 and the fourth lens 42 are coaxially arranged. The third filter 44 is a 532nm long-wavepass filter, positioned at a 45° angle to the fourth reflector 43, and is used to filter the 532nm laser signal while retaining the Raman signal. The fourth filter 45 is a 785nm long-wavepass filter, positioned at a 45° angle to the second dichroic mirror 21, and is used to filter the 785nm laser signal while retaining the Raman signal. The fourth dichroic mirror 41 is located on the other side of the first dichroic mirror 11 (to the left of the first dichroic mirror 11 in the figure) and on the other side of the second dichroic mirror 21 (to the left of the second dichroic mirror 21 in the figure). It is positioned at a 45° angle to the third filter 44, and is used to reflect the 532nm Raman signal while transmitting the 785nm Raman signal. The fourth lens 42 is located on the side of the fourth dichroic mirror 41 away from the first dichroic mirror or the second dichroic mirror (to the left of the fourth dichroic mirror 41 in the figure) and focuses the 532nm Raman signal and the 785nm Raman signal, that is, focuses the 532nm and 785nm Raman signals to the end face of the transmission fiber, and then inputs the Raman signals into the external spectrometer through the transmission fiber.

[0056] In this embodiment, as a specific example, the first lens 12, the second lens 25, the third lens 32, and the fourth lens 42 are all aspherical lenses. The first reflector 13, the second reflector 22, the third reflector 23, and the fourth reflector 43 are all silver-coated reflectors.

[0057] The specific parameters of the first filter 14 are: bandwidth 4nm, absorbance OD6, AOI: 0 degrees; the specific parameters of the second filter 24 are: bandwidth 6nm, absorbance OD6, AOI: 0 degrees; the specific parameters of the third filter 44 are: T% ≥ 90% @ 535nm-724nm, OD6 @ 530nm-532.5nm, AOI: 0 degrees; the specific parameters of the fourth filter 45 are: T% ≥ 90% @ 794nm-1050nmnm, OD6 @ 784nm-786nm, AOI: 0 degrees.

[0058] Specific parameters of the first dichroic mirror 11 are: AOI: 45 degrees, T% ≥ 90% @ 535nm-724nm, R% ≥ 95% @ 530nm-532.5nm; specific parameters of the second dichroic mirror 21 are: AOI: 45 degrees, T% ≥ 90% @ 794nm-1050nm, R% ≥ 95% @ 784nm-786nm; specific parameters of the third dichroic mirror 31 are: AOI: 45 degrees, R% ≥ 97% @ 760-1000nm, T% ≥ 98% @ 400-700nm; specific parameters of the fourth dichroic mirror 41 are: AOI: 45 degrees, R% ≥ 95% @ 530-615nm, T% ≥ 97% @ 680-1100nm.

[0059] See also Figure 1 The Raman spectrometer of this embodiment includes: a dual-wavelength Raman probe, a first laser light source 5, a second laser light source 6, and a spectrometer 7. The first laser light source 5 uses a commercially available 532nm laser with an FC interface, which is coupled to a transmission fiber and connected to the first lens 12 via the transmission fiber 8. The second laser light source 6 uses a commercially available 785nm laser with an FC interface, which is coupled to a transmission fiber 8 and connected to the second lens 25 via the transmission fiber 8. The spectrometer 7 can be any common commercial spectrometer, which is coupled to the transmission fiber 8 and the SMA interface, and then connected to the fourth lens 42 to achieve signal connection, so as to input the first preset wavelength Raman signal and the second preset wavelength Raman signal into the spectrometer for signal analysis.

[0060] Based on the above structural description, the working principle of this embodiment is specifically described as follows: 532nm laser light and 785nm laser light are output by the first laser light source 5 and the second laser light source 6, respectively. The first dichroic mirror 11 is disposed on the emission optical path of the 532nm laser light. The 532nm laser light is reflected by the first dichroic mirror 11 (one side of the first dichroic mirror 11 receives the laser light beam of the first preset wavelength and forms a reflected beam on one side of the first dichroic mirror 11, which is named the first reflected beam for convenience of description, and the same applies hereinafter) to the third dichroic mirror 31, and then transmitted through the third dichroic mirror 31 (one side of the third dichroic mirror 31 receives the first reflected beam and forms the first transmitted beam on the other side of the third dichroic mirror 31) to the third lens 32. After being focused by the third lens 32, the light is irradiated onto the sample to be tested, thereby forming a complete optical path for the 532nm laser beam to be emitted. Similarly, the second dichroic mirror 21 is arranged in the optical path for the 785nm laser beam to be emitted. The 785nm laser beam is reflected by the second dichroic mirror 21 (one side of the second dichroic mirror 21 receives the 785nm laser beam and forms a second reflected beam on one side of the second dichroic mirror 21) to the third dichroic mirror 31, and then reflected by the third dichroic mirror 31 (the other side of the third dichroic mirror 31 receives the second reflected beam and forms a third reflected beam on the other side of the third dichroic mirror 31) to the third lens 32. After being focused by the third lens 32, the light is irradiated onto the sample to be tested, thereby forming a complete optical path for the 785nm laser beam to be emitted.

[0061] On this basis, the above-mentioned first transmitted light beam is focused and irradiated onto the surface of the sample to be measured. The 532nm Raman signal scattered by the interaction between the laser and the molecules of the sample is collimated by the third lens 32. The collimated 532nm Raman signal is transmitted through the third dichroic mirror 31 (the other side of the third dichroic mirror 31 receives the collimated 532nm Raman signal and forms a first transmission signal on one side of the third dichroic mirror 31), then transmitted through the first dichroic mirror 11 (one side of the first dichroic mirror 11 receives the first transmission signal and forms a second transmission signal on the other side of the first dichroic mirror 11), and then is emitted to the fourth dichroic mirror 41 (one side of the fourth dichroic mirror 41 receives the second transmission signal and forms a first reflection signal on one side of the fourth dichroic mirror 41). It is then focused by the fourth lens 42 and connected to the spectrometer 7, thereby forming a complete 532nm Raman signal acquisition channel.

[0062] Similarly, the third reflected light beam is focused and irradiated onto the sample to be measured. The 785 nm Raman signal scattered by the interaction between the laser light and the molecules of the sample is collimated by the third lens 32. The collimated 785 nm Raman signal is sequentially reflected by the third dichroic mirror 31 (the other side of the third dichroic mirror 31 receives the collimated 785 nm Raman signal and forms a second reflected signal on the other side of the third dichroic mirror 31), then transmitted through the second dichroic mirror 21 (one side of the second dichroic mirror 21 receives the second reflected signal and forms a third transmitted signal on the other side of the second dichroic mirror 21), and then irradiated onto the fourth dichroic mirror 41 (the other side of the fourth dichroic mirror 41 receives the third transmitted signal and forms a fourth transmitted signal on one side of the fourth dichroic mirror 41). After being focused by the fourth lens 42, the signal is connected to the spectrometer 7, thereby forming a complete 785 nm Raman signal acquisition channel.

[0063] According to the above principle, under dual-wavelength laser excitation of 532nm and 785nm, the 532nm laser passes through the first laser module and the dual-wavelength acquisition module, irradiating the sample. The scattered 532nm Raman signal is ultimately focused by the Raman filter module onto an external spectrometer for Raman signal analysis. Simultaneously, the 785nm laser passes through the second laser module and the dual-wavelength acquisition module, irradiating the sample. Another Raman signal (i.e., the second preset wavelength Raman signal) is ultimately focused by the Raman filter module onto the same external spectrometer for Raman signal analysis. Therefore, this embodiment integrates the Raman channels into a single spectral channel, enabling dual-wavelength Raman signal collection and analysis using a single spectral channel. This single channel allows dual-wavelength Raman signal analysis to be performed using only a single spectrometer. This has the advantages of reducing costs, simplifying overall equipment size, and simplifying equipment operation requirements.

[0064] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A dual-wavelength Raman probe, characterized in that: The system comprises a first laser module, a second laser module, a dual-wavelength acquisition module and a Raman filter module, wherein the first laser module comprises a first dichroic mirror, which is used to reflect a laser beam of a first preset wavelength and transmit a Raman signal of the first preset wavelength; the second laser module comprises a second dichroic mirror, which is used to reflect a laser beam of a second preset wavelength and transmit a Raman signal of the second preset wavelength; The dual-wavelength acquisition module includes a third dichroic mirror and a third lens. The third dichroic mirror is located on one side of the first dichroic mirror and on one side of the second dichroic mirror. The third dichroic mirror is used to transmit the first preset wavelength laser beam and the first preset wavelength Raman signal respectively and reflect the second preset wavelength laser beam and the second preset wavelength Raman signal respectively. The third lens is located on a side of the third dichroic mirror away from the first dichroic mirror and focuses the first preset wavelength laser beam and the second preset wavelength laser beam respectively. The third lens collimates the first preset wavelength Raman signal and the second preset wavelength Raman signal respectively. The Raman filter module includes a fourth dichroic mirror and a fourth lens. The fourth dichroic mirror is located on the other side of the first dichroic mirror and on the other side of the second dichroic mirror. The fourth dichroic mirror is used to reflect the first preset wavelength Raman signal and transmit the second preset wavelength Raman signal. The fourth lens is located on the side of the fourth dichroic mirror away from the first dichroic mirror and focuses the first preset wavelength Raman signal and the second preset wavelength Raman signal respectively. The specific parameters of the first dichroic mirror are: AOI: 45 degrees, T% ≥ 90% @ 535nm-724nm, R% ≥ 95% @ 530nm-532.5nm; the specific parameters of the second dichroic mirror are: AOI: 45 degrees, T% ≥ 90% @ 794nm-1050nm, R% ≥ 95% @ 784nm-786nm; the specific parameters of the third dichroic mirror are: AOI: 45 degrees, R% ≥ 97% @ 760-1000nm, T% ≥ 98% @ 400-700nm; the specific parameters of the fourth dichroic mirror are: AOI: 45 degrees, R% ≥ 95% @ 530-615nm, T% ≥ 97% @ 680-1100nm.

2. The dual-wavelength Raman probe according to claim 1, characterized in that: The first laser module further includes a first lens, and the second laser module further includes a second lens. The first lens and the second lens are collimating lenses respectively. The first preset wavelength laser beam is emitted toward one side of the first dichroic mirror via the first lens, and the second preset wavelength laser beam is emitted toward one side of the second dichroic mirror via the second lens.

3. The dual-wavelength Raman probe according to claim 1 or 2, characterized in that: The first laser module further includes a first reflector, which is used to reflect the laser beam of the first preset wavelength so that the laser beam of the first preset wavelength is emitted toward one side of the first dichroic mirror.

4. The dual-wavelength Raman probe according to claim 3, characterized in that: The first laser module further includes a first filter having a transmission wavelength consistent with the first preset wavelength laser beam, and the first preset wavelength laser beam is emitted to one side of the first dichroic mirror through the first filter.

5. The dual-wavelength Raman probe according to claim 1 or 2, characterized in that: The second laser module also includes a second reflector and / or a third reflector, the second reflector is used to reflect the second preset wavelength laser beam so that the second preset wavelength laser beam is emitted toward one side of the second dichroic mirror; the third reflector is used to respectively reflect the second preset wavelength laser beam and the second preset wavelength Raman signal so that the second preset wavelength laser beam is emitted toward the other side of the third dichroic mirror, and the second preset wavelength Raman signal is emitted toward one side of the second dichroic mirror.

6. The dual-wavelength Raman probe according to claim 5, characterized in that: The second laser module further includes a second filter having a transmission wavelength consistent with the second preset wavelength laser beam, and the second preset wavelength laser beam is emitted to one side of the second dichroic mirror through the second filter.

7. The dual-wavelength Raman probe according to claim 1 or 2, characterized in that: The Raman filter module also includes a fourth reflector, a third filter having a cutoff wavelength consistent with the first preset wavelength Raman signal, and a fourth filter having a cutoff wavelength consistent with the second preset wavelength Raman signal. The fourth reflector is located on the other side of the first dichroic mirror and is used to reflect the first preset wavelength Raman signal so that the first preset wavelength Raman signal is emitted toward a side of the fourth dichroic mirror away from the first dichroic mirror. The third filter and the fourth filter are respectively long-pass filters. The first preset wavelength Raman signal is emitted to one side of the fourth dichroic mirror via the third filter, and the second preset wavelength Raman signal is emitted to the other side of the fourth dichroic mirror via the fourth filter.

8. A Raman spectrometer, characterized in that: The invention comprises the dual-wavelength Raman probe according to any one of claims 1 to 7.

9. The Raman spectrometer according to claim 8, characterized in that It also includes a first laser light source and a second laser light source. The first laser light source is connected to the first laser module signal through a transmission optical fiber, and the second laser light source is connected to the second laser module signal through a transmission optical fiber.

10. The Raman spectrometer according to claim 8 or 9, characterized in that: It also includes a spectrometer, which is connected to the fourth lens signal through a transmission optical fiber.

Images