CN219842328U - Laser Raman gas tank and gas detector - Google Patents
Laser Raman gas tank and gas detector Download PDFInfo
- Publication number
- CN219842328U CN219842328U CN202321020559.1U CN202321020559U CN219842328U CN 219842328 U CN219842328 U CN 219842328U CN 202321020559 U CN202321020559 U CN 202321020559U CN 219842328 U CN219842328 U CN 219842328U
- Authority
- CN
- China
- Prior art keywords
- raman
- laser
- gas
- focusing lens
- laser raman
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000001069 Raman spectroscopy Methods 0.000 title claims abstract description 126
- 239000010453 quartz Substances 0.000 claims abstract description 33
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 33
- 239000013307 optical fiber Substances 0.000 claims description 18
- 238000001914 filtration Methods 0.000 claims description 12
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims description 3
- 239000000835 fiber Substances 0.000 claims 1
- 238000004458 analytical method Methods 0.000 abstract description 11
- 238000005516 engineering process Methods 0.000 abstract description 4
- 239000007789 gas Substances 0.000 description 59
- 230000006872 improvement Effects 0.000 description 7
- 238000001237 Raman spectrum Methods 0.000 description 6
- 238000001514 detection method Methods 0.000 description 5
- 238000002955 isolation Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 3
- 230000035945 sensitivity Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 238000010943 off-gassing Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000003044 adaptive effect Effects 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000010249 in-situ analysis Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000013618 particulate matter Substances 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Landscapes
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
Abstract
The utility model discloses a laser Raman gas cell and a gas detector, wherein the gas cell comprises a confocal Raman enhancement cavity with an opening and a quartz tube filled with a gas sample, and the quartz tube is arranged in the confocal Raman enhancement cavity and is concentric with the confocal Raman enhancement cavity. According to the utility model, the gas sample is packaged in the quartz tube in the confocal Raman enhancement cavity, and the quartz tube and the confocal Raman enhancement cavity are concentrically arranged, so that laser enters the confocal Raman enhancement cavity and reacts with the gas sample in the quartz tube to generate a Raman signal, the contact between the gas sample and the confocal Raman enhancement cavity is avoided, the gas sample is prevented from corroding or polluting a laser Raman gas cell, the applicability of a laser Raman atmosphere analysis technology is improved, the laser Raman gas cell is simplified, and the risk of sample distortion is eliminated. And the structure of the laser Raman gas detector is improved, so that the volume of the laser Raman gas detector is reduced.
Description
Technical Field
The utility model relates to the technical field of laser Raman spectroscopy, in particular to a laser Raman gas cell and a gas detector.
Background
The laser Raman spectrum technology is widely applied to analysis and detection of substances, and has the technical advantages of short analysis period, simple device, capability of detecting various gases simultaneously and the like in the aspect of gas detection. However, because the scattering cross section of the gas molecules is small, the Raman scattering signal of the gas molecules is only 10 of the incident laser intensity -6 ～10 -8 There is a problem of insufficient sensitivity.
At present, many methods are adopted to enhance the detection sensitivity of the Raman spectrum, wherein the method of laser Raman enhancement in-cavity multiple reflection enhancement is typically adopted to improve the Raman excitation efficiency of gas molecules and the collection efficiency of Raman signals. However, the existing laser Raman enhancement cavities are all used for directly introducing a gas sample to be detected into the enhancement cavities, and the analysis of the sample atmosphere is realized; however, the atmosphere is in direct contact with the inner wall of the enhanced cavity, so that the risks of pollution and corrosion of the cavity lens exist, and the method is particularly obvious in a high-humidity corrosive atmosphere sample.
To eliminate the above adverse effects, pretreatment techniques are generally introduced to remove harmful components in the gas sample: such as humidity, particulate matter, etc.; and then the laser Raman enhancement cavity is introduced for detection. The introduction of the pretreatment technology not only increases the complexity of the analysis device, but also is unfavorable for the miniaturization design of the laser Raman enhancement cavity; distortion of the gas sample may also be caused.
Disclosure of Invention
The utility model aims to provide a laser Raman gas cell and a gas detector, which are used for solving the problems that in the prior art, after a gas sample to be detected is preprocessed, the gas sample to be detected is led into a laser Raman enhancement cavity, the complexity of an analysis device is increased, and the distortion of the gas sample to be detected is easily caused.
The utility model solves the problems by the following technical proposal:
a laser Raman gas cell comprises a confocal Raman enhancement cavity formed with an opening and a quartz tube filled with a gas sample, wherein the quartz tube is arranged in the confocal Raman enhancement cavity and is concentric with the confocal Raman enhancement cavity.
As a further improvement, the quartz tube is clamped with the confocal Raman enhancement cavity.
In addition, the utility model also provides the following technical scheme:
a laser Raman gas detector comprises the laser Raman gas cell and a Raman spectrometer, and the Raman spectrometer is used for receiving and analyzing a Raman signal output by the laser Raman gas cell.
As a further improvement, the laser device, the isolation focusing lens group and the total reflection mirror are sequentially arranged, the laser device is connected with the isolation focusing lens group through an incident optical fiber, and laser emitted through the isolation focusing lens group is reflected into the laser Raman gas pool through the total reflection mirror.
As a further improvement thereof, the total reflection mirror is disposed obliquely with respect to the isolated focusing lens group.
As a further improvement, the isolated focusing lens group comprises a shell, and a collimating lens, a bandpass filter and a focusing lens which are sequentially arranged in the shell.
As a further improvement, the incident optical fiber is inserted into the housing, and a quartz optical fiber with a low hydroxyl value is adopted.
As a further improvement, a collecting and filtering component is arranged between the laser Raman gas tank and the Raman spectrometer.
As a further improvement, the collecting and filtering assembly comprises a large-caliber collecting lens, a long-wave pass filter and an emergent focusing lens, and the Raman signal sequentially passes through the large-caliber collecting lens, the long-wave pass filter and the emergent focusing lens.
Compared with the prior art, the utility model has the following advantages:
according to the utility model, the gas sample is packaged in the quartz tube in the confocal Raman enhancement cavity, and the quartz tube and the confocal Raman enhancement cavity are concentrically arranged, so that laser enters the confocal Raman enhancement cavity and reacts with the gas sample in the quartz tube to generate a Raman signal, the contact between the gas sample and the confocal Raman enhancement cavity is avoided, the gas sample is prevented from corroding or polluting a laser Raman gas cell, the applicability of a laser Raman atmosphere analysis technology is improved, the laser Raman gas cell is simplified, and the risk of sample distortion is eliminated. And the structure of the laser Raman gas detector is improved, so that the volume of the laser Raman gas detector is reduced.
Drawings
Fig. 1 is a schematic structural diagram of a laser raman gas detector according to the present utility model.
Fig. 2 is a schematic structural diagram of an isolated focusing lens group according to the present utility model.
Fig. 3 is a schematic diagram of the co-operation of the confocal raman enhancement cavity and the collection and filtration assembly of the present utility model.
FIG. 4 is a schematic view of the collection and filtration assembly of the present utility model.
Reference numerals:
1. a laser; 2. a raman spectrometer; 3. isolating the focusing lens group; 4. a total reflection mirror; 5. a laser Raman gas cell; 31. an incident optical fiber; 32. a housing; 33. a collimating lens; 34. a bandpass filter; 35. a focusing lens; 51. confocal raman enhancement cavities; 52. a collection and filtration assembly; 53. a quartz tube; 54. reflecting the laser; 55. a raman signal; 56. an exit focusing lens; 57. a long-wave pass filter; 58. and a large-caliber collecting lens.
Detailed Description
The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.
Example 1
A laser Raman gas cell comprises a confocal Raman enhancement cavity 51 formed with an opening, and a quartz tube 53 containing a gas sample, wherein the quartz tube 53 is arranged in the confocal Raman enhancement cavity 51 and concentric with the confocal Raman enhancement cavity 51. The gas sample to be measured is held in the quartz tube 53 and does not enter the confocal raman enhancement cavity 51, and therefore, does not contaminate or corrode the confocal raman enhancement cavity 51 and other subsequent components.
Preferably, the quartz tube 53 is clamped with the confocal raman enhancement cavity 51, and the quartz tube 53 is used as a replaceable consumable material and is clamped with the confocal raman enhancement cavity by adopting a clamping sleeve structure, so that the replacement is facilitated.
Example 2
Referring to fig. 1, a laser raman gas detector comprises a laser 1, a raman spectrometer 2, an isolated focusing lens group 3, a total reflection mirror 4, a laser raman gas cell 5 and the like, wherein the laser 1 is a special laser for raman, and the laser 1 is connected with the isolated focusing lens group 3 through an incident optical fiber so that laser output by the laser 1 is transmitted to the isolated focusing lens group 3 through the incident optical fiber; the back side of the isolation focusing lens group 3 is obliquely provided with a total reflection mirror 4, laser focused by the isolation focusing lens group 3 enters the laser Raman gas tank 5 through an opening of the laser Raman gas tank 5 after being reflected by the total reflection mirror 4, and is conveyed to the Raman spectrometer 2 for Raman spectrum analysis through the opening of the laser Raman gas tank 5 after being reflected for a plurality of times in the laser Raman gas tank 5.
Further, referring to fig. 2, in the present embodiment, the isolated focusing lens group 3 is composed of an incident optical fiber 31, a housing 32, a collimator lens 33, a bandpass filter 34, a focusing lens 35, and the like. The incident optical fiber 31 is inserted into the housing 32, and a collimating lens 33, a bandpass filter 34 and a focusing lens 35 are sequentially disposed in the housing 32, preferably, the incident optical fiber 31 is a quartz optical fiber with a low hydroxyl value, and is used for reducing a fluorescent signal generated by laser light output by the laser 1; because the incident optical fiber 31 filters out the generated fluorescent signal, and the bandpass filter 34 is utilized to only allow the incident laser to pass through, the spectral purity of the incident laser entering the laser Raman gas cell 5 is ensured.
Referring to fig. 3-4, in this embodiment, the laser raman gas cell 5 is a disk-type enhanced type, and includes a confocal raman enhancement cavity 51 provided with an opening and integrated, and a quartz tube 53 disposed in a middle position in the confocal raman enhancement cavity 51, where the quartz tube 53 is disposed concentrically with the confocal raman enhancement cavity 51; the gas sample is filled in the quartz tube 53, after the reflected laser 54 reflected by the total reflection mirror 4 enters the confocal raman enhancement cavity 51 through the opening, the overlapping area of the reflected laser 54 is inside the quartz tube 53, the gas sample inside the quartz tube is excited to generate a raman signal 55, and the raman signal 55 is then transmitted to the raman spectrometer 2 for raman spectrum analysis.
Further, a large-caliber collecting and filtering assembly 52 is arranged between the laser Raman gas tank 5 and the Raman spectrometer 2, and the Raman signal 55 generated by the laser Raman gas tank 5 is collected and filtered by the collecting and filtering assembly 52 and then is transmitted to the Raman spectrometer 2 for Raman spectrum analysis, so that atmosphere components and content information are obtained. The collection and filtering assembly includes a large-caliber collection lens 58, a long-wave pass filter 57 and an exit focusing lens 56, and the raman signal sequentially passes through the large-caliber collection lens, the long-wave pass filter and the exit focusing lens and is transmitted to the raman spectrometer by an exit optical fiber.
The Raman spectrometer 2 adopts a large slit design for improving the Raman luminous flux; a constant temperature module is arranged in the device, so that the stability of long-time integration is ensured; prism deflection design, eliminating Raman shift by 200cm -1 Detector saturation problems with downward rayleigh scattering.
In a specific embodiment, the laser Raman gas detector adopts a laser with the wavelength of 100mW and 532nm, and the incident optical fiber of the laser adopts a core diameter of 105 mu m; the Raman spectrometer adopts refrigeration type, the adaptive wavelength is 532nm, the slit is 50 mu m, the incident optical fiber of the Raman spectrometer adopts multimode line array incident optical fiber, and the core diameter is 200 mu m; the center wavelength of the bandpass filter 34 in the isolated focusing lens group 3 was 532nm, and the half-width was 2nm. The laser Raman gas cell 5 is formed by splicing independent reflectors, and the focal length is 25.4mm. The quartz tube 53 has an outer diameter of 9.5mm and a wall thickness of 1mm, and is connected with the gas circuit by adopting a gold-plated red copper cutting sleeve, and the leakage rate is better than 10 -6 Pa·L -1 ·s -1 。
Incident laser beamThe collimating lens 33 is focused and collimated, then enters the cavity of the laser Raman gas tank from the opening after being reflected by the total reflection mirror, penetrates through the gas sample to be detected in the quartz tube 53, is reflected by the inner wall of the integrated confocal Raman enhancement cavity 51, penetrates through the gas sample to be detected in the quartz tube 53 again, and under the combined action of the upper reflection mirror and the lower reflection mirror in the cavity, the incident laser is reflected repeatedly in the cavity, and each reflection penetrates through the gas sample of the quartz tube 53 and is excited to generate a Raman signal 55. The Raman signal 55 is reflected by the confocal Raman enhancement cavity 51, converged to a large-caliber collecting lens 58 of the collecting and filtering assembly for collimation, then the laser is filtered by a long-wave pass filter 57, converged to a quartz emergent optical fiber by an emergent focusing lens 56 of the collecting and filtering assembly, and finally sent to a Raman spectrometer 2 for Raman spectrum analysis, so that ppm-level H is realized 2 、O 2 、N 2 、CO 2 、H 2 O、CH 4 、NO 2 And carrying out nondestructive in-situ analysis on the gas, wherein the pressure of the gas sample covers 0.1 kPa-10 MPa.
The utility model has the advantages of high resolution, high sensitivity, good reproducibility, low cost, portability and the like, is suitable for real-time, online and continuous identification and monitoring of the components and the concentration changes thereof in the gas sample, and is especially suitable for the online nondestructive monitoring of the vacuum stability outgassing of the energetic material and the nondestructive detection of the outgassing by the Brinell pressure method.
Although the utility model has been described herein with reference to the above-described illustrative embodiments thereof, the foregoing embodiments are merely preferred embodiments of the present utility model, and it should be understood that the embodiments of the present utility model are not limited to the above-described embodiments, and that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the scope and spirit of the principles of this disclosure.
Claims (9)
1. The laser Raman gas cell is characterized by comprising a confocal Raman enhancement cavity formed with an opening and a quartz tube filled with a gas sample, wherein the quartz tube is arranged in the confocal Raman enhancement cavity and is concentric with the confocal Raman enhancement cavity.
2. The laser raman gas cell of claim 1 wherein the quartz Guan Yugong focal raman enhancement cavity phase is clamped.
3. A laser raman gas detector comprising a raman spectrometer and a laser raman gas cell according to claim 1 or 2, wherein the raman signal output from the laser raman gas cell is received and analyzed by the raman spectrometer.
4. The laser Raman gas detector according to claim 3, further comprising a laser, an isolated focusing lens group and a total reflection mirror, wherein the laser, the isolated focusing lens group and the total reflection mirror are sequentially arranged, the laser is connected with the isolated focusing lens group through an incident optical fiber, and laser emitted through the isolated focusing lens group is reflected into the laser Raman gas pool through the total reflection mirror.
5. A laser raman gas detector according to claim 4 wherein said total reflection mirror is disposed obliquely with respect to the isolated focusing lens group.
6. The laser raman gas detector according to claim 4 wherein the isolated focusing lens group comprises a housing, and a collimating lens, a bandpass filter and a focusing lens sequentially disposed in the housing.
7. The laser raman gas detector according to claim 6 wherein the incident optical fiber is inserted into the housing and a low hydroxyl value quartz fiber is used.
8. A laser raman gas detector according to claim 3 wherein a collection and filtration assembly is provided between the laser raman gas cell and the raman spectrometer.
9. The laser raman gas detector according to claim 8 wherein the collection and filtering assembly comprises a large caliber collection lens, a long wave pass filter and an exit focusing lens, and the raman signal passes through the large caliber collection lens, the long wave pass filter and the exit focusing lens in sequence.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321020559.1U CN219842328U (en) | 2023-04-28 | 2023-04-28 | Laser Raman gas tank and gas detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321020559.1U CN219842328U (en) | 2023-04-28 | 2023-04-28 | Laser Raman gas tank and gas detector |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN219842328U true CN219842328U (en) | 2023-10-17 |
Family
ID=88298151
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202321020559.1U Active CN219842328U (en) | 2023-04-28 | 2023-04-28 | Laser Raman gas tank and gas detector |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN219842328U (en) |
-
2023
- 2023-04-28 CN CN202321020559.1U patent/CN219842328U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5112127A (en) | Apparatus for measuring Raman spectra over optical fibers | |
| US4200802A (en) | Parabolic cell analyzer | |
| CN105606571B (en) | A kind of aspherical reflective laser induction excitation of spectra/collection system | |
| CN112414992A (en) | Raman spectrum excitation enhancement module | |
| CN116359202A (en) | Laser Raman gas detector and detection method thereof | |
| CN101504371A (en) | Quantitative determination instrument for melamine content in liquid milk | |
| CN100351624C (en) | Dissolved gas analyzer of electric power transformer oil based on Raman technology | |
| CN113218930B (en) | Raman spectrum enhancement device and gas analysis system | |
| US20040239924A1 (en) | Laser-induced fluorescence analysis device and separation apparatus comprising same | |
| CN108982467B (en) | Raman fiber micro probe with low spectrum background | |
| CN116380872A (en) | Laser-induced breakdown spectroscopy aerosol single-particle high-sensitivity detection device | |
| CN111982884A (en) | Compact 266nm shortwave ultraviolet Raman spectrometer | |
| CN219842328U (en) | Laser Raman gas tank and gas detector | |
| CN110672583A (en) | Raman spectrum excitation structure and gas analysis method | |
| CN113804671A (en) | High-sensitivity Raman spectrum detection system | |
| US20110042585A1 (en) | Fiber optical assembly for fluorescence spectrometry | |
| CN112213296A (en) | Device and method for detecting uranium and plutonium content in tail gas of radioactive after-treatment plant | |
| CN106680260A (en) | Portable coherent anti-Stokes Raman spectrometer | |
| US9110024B2 (en) | Fiber optical asssembly for fluorescence spectrometry | |
| CN215297140U (en) | Ellipsoidal laser reflection focusing module | |
| CN115326777A (en) | Device and system for enhancing gas Raman signal in hollow-core optical fiber | |
| CN219842324U (en) | Laser Raman gas cell and probe | |
| CN211086086U (en) | Device for multiplying signal | |
| CN212059104U (en) | Wide-spectrum high-sensitivity Raman spectrometer | |
| CN210401221U (en) | Multi-hot-spot excitation primary feedback Raman spectrum testing device in liquid environment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |