Gas Raman spectrum measurement device based on toric reflection cavity enhancement

Abstract

The utility model discloses a gas Raman spectrum measuring device based on toric reflection cavity enhancement in the technical field of gas Raman spectrum detection, which comprises a box body, an inlet is arranged at the bottom of the left side of the box body, a mounting rack is arranged at the bottom of the left side of the box body, the mounting rack is positioned above the inlet, and the mounting rack is positioned above the inlet. A laser is rotationally connected to the bottom of the mounting frame, a connecting plate is arranged on the right side of the top of the laser, a laser book shrinking device is arranged on the right side of the bottom of the connecting plate, a first-section cavity mirror is arranged on the left side of an inner cavity of the box body, a tail-end cavity mirror is arranged on the right side of the inner cavity of the box body, and a signal collection reflecting mirror is arranged on the top of the inner cavity of the box body; a Raman signal receiving device is arranged at the bottom of an inner cavity of the box body, a fixing plate is arranged at the bottom of the inner cavity of the box body, and the problems that when the device is used, although multiple reflections of laser are achieved, the structure is complex, debugging and installation are difficult, and the applicability is limited are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of gas Raman spectrum detection, in particular to a gas Raman spectrum measurement device based on complex surface reflection cavity enhancement. Background Art

[0002] Laser Raman spectroscopy is a highly sensitive method widely used for gas composition analysis. It uses laser light to illuminate a gas, generating the Raman effect. The wavelength of the Raman scattered light determines the gas composition, and the intensity of the scattered light determines the gas concentration. Compared to other spectroscopic gas detection methods (such as infrared absorption spectroscopy and photoacoustic spectroscopy), Raman spectroscopy utilizes a single-wavelength laser to simultaneously measure multi-component gas mixtures. The Raman peak of water vapor is relatively distant from other gases, so water vapor in a gas sample has a minimal impact on Raman spectroscopy.

[0003] For example, the folded multi-reflector cavity for gas Raman signal enhancement, disclosed in publication number CN113295669B, comprises a head-end cavity mirror, a terminal cavity mirror, and a plurality of folding mirrors; the head-end cavity mirror, the terminal cavity mirror, and the plurality of folding mirrors constitute an enhancement cavity with a folded reflective light path; the head-end cavity mirror is provided with a light-through hole, through which the laser passes through the head-end cavity mirror and enters the enhancement cavity, wherein the angle between the incident direction of the laser and the first folding mirror it reaches after entering the enhancement cavity is non-perpendicular; after entering the enhancement cavity, the laser is reflected by the folding mirror and then reflected by the terminal cavity mirror; the reflected laser is reflected multiple times in the enhancement cavity along different paths until the laser reaches the head-end cavity mirror, just passing through the light-through hole again and exiting the enhancement cavity. The folded multi-reflector cavity proposed in the present invention can cause the laser to reflect hundreds of times within the cavity, and the detection limit of multi-component gas Raman spectroscopy can reach the sub-ppm level.

[0004] Although the above device can realize multiple reflections of laser light when in use, it uses multiple reflectors, has a complex structure, is difficult to debug and install, and has limited applicability. Utility Model Content

[0005] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and in the abstract and title of the present invention to avoid obscuring the purpose of this section, the abstract and the title of the utility model, and such simplifications or omissions shall not be used to limit the scope of the present invention.

[0006] Therefore, the purpose of the present invention is to provide a gas Raman spectroscopy measurement device based on a complex surface reflection cavity enhancement, which can solve the problem that when the above-mentioned device is used, although multiple reflections of the laser are achieved, multiple mirrors are used, the structure is relatively complex, and debugging and installation are difficult, and the applicability is limited.

[0007] In order to solve the above technical problems, the present invention provides a gas Raman spectroscopy measurement device based on complex surface reflection cavity enhancement, adopts the following technical solution: it includes a box body, an entrance is opened at the left bottom of the box body, a mounting bracket is provided at the left bottom of the box body, the mounting bracket is located above the entrance, a laser is rotatably connected to the bottom of the mounting bracket, a connecting plate is provided on the top right side of the laser, a laser book shrinking device is provided on the bottom right side of the connecting plate, a first-section cavity mirror is provided on the left side of the box body inner cavity, an end cavity mirror is provided on the right side of the box body inner cavity, a signal collecting reflector is provided on the top of the box body inner cavity, a Raman signal receiving device is provided on the bottom of the box body inner cavity, a fixing plate is provided on the bottom of the box body inner cavity, the fixing plate is located on the right side of the Raman signal receiving device, a Raman collimating lens is provided on the left top of the fixing plate, a support plate is provided on the left side of the box body inner cavity, and an air chamber is provided on the right side of the support plate.

[0008] Optionally, the first-section cavity mirror and the end cavity mirror are both complex curved reflectors, and the cavity mirror diameters of the first-section cavity mirror and the end cavity mirror are both 25.4 mm.

[0009] By adopting the above technical solution, reflection between the first-section cavity mirror and the end cavity mirror is achieved.

[0010] Optionally, the longitudinal curvature radius of the first-section laparoscope and the end-section laparoscope is 100 mm, the transverse curvature radius of the first-section laparoscope and the end-section laparoscope is 250 mm, and the distance between the first-section laparoscope and the end-section laparoscope is 200 mm.

[0011] By adopting the above technical solution, the light beam in the cavity is converged at the center of the cavity.

[0012] Optionally, the signal collecting reflector is a plano-concave reflector, the diameter of the signal collecting reflector is 25.4 mm, and the focal length of the signal collecting reflector is 30 mm.

[0013] By adopting the above technical solution, a signal collecting reflector is installed.

[0014] Optionally, the focal length of the Raman collimating lens is 30 mm, and the focusing position of the Raman collimating lens coincides with the focusing position of the signal collecting reflector.

[0015] By adopting the above technical solution, the light beams are focused to where they converge.

[0016] Optionally, the signal receiving end of the Raman signal receiving device is a bowl-shaped structure, and the inner wall of the bowl-shaped structure is a reflective surface.

[0017] By adopting the above technical solution, the spatial light convergence can be achieved in a limited way, thereby improving the signal collection efficiency.

[0018] In summary, the present invention has at least one of the following beneficial effects: a complex curved mirror is used to realize a dense multiple-reflection Raman gas cell design, achieving hundreds of laser reflections, a simple structure, and convenient debugging. Combined with a lateral signal collection method and a unique Raman signal collection device with a bowl-shaped structure, the number of laser reflections and the detection sensitivity of the Raman signal are significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 It is a structural diagram of the utility model;

[0021] Figure 2 It is a schematic diagram of the cross-sectional structure of the present utility model.

[0022] Explanation of the reference numerals: 1. Box; 101. Entrance; 102. Fixing plate; 103. Support plate; 2. Mounting frame; 3. Laser; 301. Connecting plate; 4. Laser beam reduction device; 5. First-section cavity mirror; 6. End cavity mirror; 7. Signal collecting reflector; 8. Raman signal receiving device; 9. Raman collimating lens; 10. Gas chamber. DETAILED DESCRIPTION

[0023] The following is combined with Figure 1-2 The utility model is described in further detail.

[0024] Example 1, refer to Figure 1-2 In this embodiment, in order to solve the problem that the above-mentioned device achieves multiple reflections of laser light, but uses multiple mirrors, has a complex structure, is difficult to debug and install, and has limited applicability, the utility model discloses a gas Raman spectroscopy measurement device based on a complex surface reflection cavity enhancement.

[0025] The utility model comprises a box body 1, an entrance 101 is provided at the bottom left side of the box body 1, a mounting bracket 2 is provided at the bottom left side of the box body 1, the mounting bracket 2 is located above the entrance 101, a laser 3 is rotatably connected to the bottom of the mounting bracket 2, a connecting plate 301 is provided on the right side of the top of the laser 3, a laser book shrinking device 4 is provided on the right side of the bottom of the connecting plate 301, a first-section cavity mirror 5 is provided on the left side of the inner cavity of the box body 1, an end cavity mirror 6 is provided on the right side of the inner cavity of the box body 1, a signal collecting reflector 7 is provided on the top of the inner cavity of the box body 1, a Raman signal receiving device 8 is provided on the bottom of the inner cavity of the box body 1, a fixing plate 102 is provided at the bottom of the inner cavity of the box body 1, the fixing plate 102 is located on the right side of the Raman signal receiving device 8, a Raman collimating lens 9 is provided on the top left side of the fixing plate 102, a support plate 103 is provided on the left side of the inner cavity of the box body 1, and an air chamber 10 is provided on the right side of the support plate 103.

[0026] The specific working principle is: using the first-section cavity mirror 5 and the end cavity mirror 6 to cooperate to realize the design of a dense multiple-reflection Raman gas cell, achieving hundreds of laser reflections, simple structure, and easy debugging. Combined with the lateral signal collection method and the unique Raman signal collection device 8 with a bowl-shaped structure, the number of laser reflections and the detection sensitivity of the Raman signal are significantly improved.

[0027] It should be noted that both the first-section cavity mirror 5 and the end cavity mirror 6 are complex curved reflectors, and the cavity mirror diameters of both the first-section cavity mirror 5 and the end cavity mirror 6 are 25.4 mm.

[0028] The above technical solution is adopted to realize reflection between the first-section cavity mirror and the end cavity mirror.

[0029] It should be noted that the longitudinal curvature radius of the first section laparoscope 5 and the end laparoscope 6 is 100 mm, the transverse curvature radius of the first section laparoscope 5 and the end laparoscope 6 is 250 mm, and the distance between the first section laparoscope 5 and the end laparoscope 6 is 200 mm.

[0030] By adopting the above technical solution, the light beam in the cavity is converged at the center of the cavity.

[0031] It should be supplemented that the signal collecting reflector 7 is a plano-concave reflector, the diameter of the signal collecting reflector 7 is 25.4 mm, and the focal length of the signal collecting reflector 7 is 30 mm.

[0032] The above technical solution is adopted to install a signal collecting reflector.

[0033] It should be additionally explained that the focal length of the Raman collimating lens 9 is 30 mm, and the focusing position of the Raman collimating lens 9 coincides with the focusing position of the signal collecting reflector 7 .

[0034] The above technical solution is adopted to focus on the convergence of the light beams.

[0035] It should be supplemented that the signal receiving end of the Raman signal receiving device 8 is a bowl-shaped structure, and the inner wall of the bowl-shaped structure is a reflective surface.

[0036] By adopting the above technical solution, the spatial light convergence can be achieved in a limited way, thereby improving the signal collection efficiency.

[0037] The above are all preferred embodiments of the present invention, and are not intended to limit the scope of protection of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A gas Raman spectroscopy measurement device based on complex surface reflection cavity enhancement, comprising a box (1), characterized in that: An entrance (101) is provided at the bottom left of the box (1), a mounting frame (2) is provided at the bottom left of the box (1), the mounting frame (2) is located above the entrance (101), a laser (3) is rotatably connected to the bottom of the mounting frame (2), a connecting plate (301) is provided on the right side of the top of the laser (3), a laser book shrinking device (4) is provided on the right side of the bottom of the connecting plate (301), a first section cavity mirror (5) is provided on the left side of the inner cavity of the box (1), and an end cavity mirror (5) is provided on the right side of the inner cavity of the box (1). A cavity mirror (6), a signal collecting reflector (7) is provided at the top of the inner cavity of the box (1), a Raman signal receiving device (8) is provided at the bottom of the inner cavity of the box (1), a fixing plate (102) is provided at the bottom of the inner cavity of the box (1), the fixing plate (102) is located on the right side of the Raman signal receiving device (8), a Raman collimating lens (9) is provided at the top of the left side of the fixing plate (102), a support plate (103) is provided on the left side of the inner cavity of the box (1), and an air chamber (10) is provided on the right side of the support plate (103).

2. The gas Raman spectroscopy measurement device based on toric reflection cavity enhancement according to claim 1, characterized in that: The first section cavity mirror (5) and the end cavity mirror (6) are both complex curved reflectors, and the cavity mirror diameters of the first section cavity mirror (5) and the end cavity mirror (6) are both 25.4 mm.

3. The gas Raman spectroscopy measurement device based on toric reflection cavity enhancement according to claim 2, characterized in that: The longitudinal curvature radius of the first section laparoscope (5) and the end laparoscope (6) is 100 mm, the transverse curvature radius of the first section laparoscope (5) and the end laparoscope (6) is 250 mm, and the distance between the first section laparoscope (5) and the end laparoscope (6) is 200 mm.

4. The gas Raman spectroscopy measurement device based on toric reflection cavity enhancement according to claim 1, characterized in that: The signal collecting reflector (7) is a plano-concave reflector, the diameter of the signal collecting reflector (7) is 25.4 mm, and the focal length of the signal collecting reflector (7) is 30 mm.

5. The gas Raman spectroscopy measurement device based on toric reflection cavity enhancement according to claim 1, characterized in that: The focal length of the Raman collimating lens (9) is 30 mm, and the focusing position of the Raman collimating lens (9) coincides with the focusing position of the signal collecting reflector (7).

6. The gas Raman spectroscopy measurement device based on toric reflection cavity enhancement according to claim 1, characterized in that: The signal receiving end of the Raman signal receiving device (8) is a bowl-shaped structure, and the inner wall of the bowl-shaped structure is a reflecting surface.

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