CN220040238U - Long-optical-path optical gas absorption cell and gas sensor - Google Patents
Long-optical-path optical gas absorption cell and gas sensor Download PDFInfo
- Publication number
- CN220040238U CN220040238U CN202321558309.3U CN202321558309U CN220040238U CN 220040238 U CN220040238 U CN 220040238U CN 202321558309 U CN202321558309 U CN 202321558309U CN 220040238 U CN220040238 U CN 220040238U
- Authority
- CN
- China
- Prior art keywords
- concave
- reflecting
- mirror
- reflector
- absorption cell
- 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
- 230000003287 optical effect Effects 0.000 title claims abstract description 47
- 238000010521 absorption reaction Methods 0.000 title claims abstract description 29
- 238000012544 monitoring process Methods 0.000 abstract description 7
- 239000007789 gas Substances 0.000 description 31
- 238000010586 diagram Methods 0.000 description 5
- 238000001514 detection method Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000000041 tunable diode laser absorption spectroscopy Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 238000002372 labelling Methods 0.000 description 1
- 238000001285 laser absorption spectroscopy Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
Abstract
The utility model discloses a long-optical-path optical gas absorption cell and a gas sensor, the long optical path optical gas absorption cell comprises a first concave reflecting mirror, a second concave reflecting mirror, an inlet hole, an outlet hole and an intermediate reflecting mirror, wherein: the reflecting surface of the first concave reflecting mirror and the reflecting surface of the second concave reflecting mirror are arranged in the same direction; the incident hole is arranged at the non-center of the first concave reflector; the middle reflector, the first concave reflector and the second concave reflector form a reflecting cavity, and the reflecting cavity is used for guiding light between the reflecting surface of the first concave reflector and the reflecting surface of the second concave reflector; the incident light rays are incident from the incident hole at an angle which is not parallel to the main axis of the first concave reflector, and are reflected for multiple times in the reflecting cavity and then are emitted from the emergent hole. The optical gas absorption cell not only can realize longer optical path under the limited volume of the gas cell, meets the monitoring requirement of low-concentration gas, but also has the advantages of high utilization rate of the lens, simple structure, small size, easy processing and effective cost reduction.
Description
Technical Field
The utility model relates to the technical field of gas detection equipment, in particular to a long-optical-path optical gas absorption cell and a gas sensor.
Background
At present, the semiconductor tunable laser absorption spectroscopy (Tunable Diode Laser Absorption Spectroscopy, TDLAS) has the characteristics of no need of pretreatment, strong selectivity, high response speed, high sensitivity, high precision and the like, and has been widely applied to the fields of industrial monitoring and environmental monitoring. Especially in the field of environmental monitoring, since the concentration of harmful pollutant gases to be monitored is very low, for a certain gas to be detected, the concentration is related to the optical path length of laser light in the gas and the intensity of light attenuation signals caused by gas absorption. Therefore, the detection precision of the low-concentration gas can be effectively improved by designing the long-optical-path gas absorption cell.
Existing gas absorption cells are typically placed in a relatively small volume of gas chamber, which results in a limited design of long optical path absorption cells, especially for monitoring of contaminated gas at concentrations in the ppm or even ppb range, often requiring optical paths of several tens to hundreds of meters within a limited volume, for which existing manufacturers typically employ multiple reflection White cells and Herriott cells. For example, in the chinese technology, patent CN113484266B, an optical path multiplier and an optical path multiplier gas absorption cell are proposed, and by adding a multiplier mirror based on the optical structure of a typical white cell, the optical path is doubled by doubling the number of optical reflections, but when actually adjusting the number of reflections of light in the gas cell, two smaller sub-mirrors are difficult to adjust. Compared with a white cell, the Huriott cell is composed of only two spherical mirrors, an optical system is simple, the optical path of the Huriott cell is easy to adjust, the mirror surface utilization rate of the Huriott cell with long optical path is low, and particularly under the condition of a limited volume air chamber, the problem that the distance between light spots on a lens and the requirement of forming a hundred-meter long optical path are difficult to consider is always met.
Disclosure of Invention
The utility model aims to provide a long-optical-path optical gas absorption cell and a gas sensor aiming at the prior art, so as to solve the problem that the high utilization rate of an optical absorption cell lens and the long optical path cannot be compatible under the condition of limited volume in the prior art.
In order to achieve the above purpose, the utility model adopts the following technical scheme:
a long optical path optical gas absorption cell comprising:
a first concave mirror;
a second concave mirror;
the reflecting surface of the first concave reflecting mirror and the reflecting surface of the second concave reflecting mirror are arranged in the same direction, and the included angle between the focal plane of the first concave reflecting mirror and the focal plane of the second concave reflecting mirror is alpha, wherein alpha is more than 0 and less than or equal to 180 degrees;
the input hole is arranged at the non-center of the first concave reflector and is used for inputting light;
an exit aperture for outputting light;
the middle reflector, the first concave reflector and the second concave reflector form a reflecting cavity, and the reflecting cavity is used for guiding light between the reflecting surface of the first concave reflector and the reflecting surface of the second concave reflector;
incident light rays enter the reflecting cavity from the incident hole at an angle which is not parallel to the main axis of the first concave reflecting mirror, and are reflected for many times in the reflecting cavity and then exit from the emergent hole.
Further, the radius of curvature of the first concave mirror is the same as the radius of curvature of the second concave mirror.
Further, the exit hole is arranged at the non-center of the first concave reflector.
Further, the exit hole coincides with the entrance hole.
Further, the exit hole is arranged at the non-center of the second concave reflector.
Further, the first concave reflecting mirror and the second curved reflecting mirror are rectangular concave reflecting mirrors.
Further, the first concave reflecting mirror and the second curved reflecting mirror are both round concave reflecting mirrors.
Further, the number of the intermediate reflectors is 2N+1, and N is more than or equal to 0.
Further, the middle reflecting mirror is a plane mirror.
Further, the middle reflector comprises two plane mirrors, the reflecting surfaces of the two plane mirrors are arranged oppositely, and the principal axes of the two plane mirrors are 90 degrees.
Further, the middle reflecting mirror is a prism, the section of the middle reflecting mirror is an isosceles triangle, and the vertex angle of the middle reflecting mirror is 90 degrees.
A gas sensor using a long optical path optical gas absorption cell as described above.
The beneficial effects of the utility model are as follows:
the utility model adopts the two non-coaxial concave reflectors which are arranged in the same direction to form the reflecting cavity by matching with the middle reflector, thus not only realizing longer optical path under the limited volume and meeting the monitoring requirement of low concentration (ppm level or even ppb level) gas, but also having high lens utilization rate, simple structure, small size, easy processing and effectively reducing the cost.
Drawings
FIG. 1 is a schematic diagram of a mirror system according to embodiment 1 of the present utility model;
FIG. 2 is a schematic diagram of a mirror system according to embodiment 2 of the present utility model;
FIG. 3 is a schematic diagram of a mirror system according to embodiment 3 of the present utility model;
FIG. 4 is a schematic diagram of a mirror system according to embodiment 4 of the present utility model;
FIG. 5 is a schematic diagram of a mirror system according to embodiment 5 of the present utility model;
labeling and describing: 1. the device comprises a first concave reflecting mirror 11, an incident hole 2, a second concave reflecting mirror 3, a plane mirror 4 and a prism.
Detailed Description
The utility model is further described below with reference to the accompanying drawings.
Referring to fig. 1-5, a long optical path optical gas absorption cell includes a first concave mirror 1, a second concave mirror 2, an incident hole 11, an exit hole, and an intermediate mirror.
The reflecting surface of the first concave reflecting mirror 1 and the reflecting surface of the second concave reflecting mirror 2 are arranged in the same direction, and an included angle between the focal plane of the first concave reflecting mirror 1 and the focal plane of the second concave reflecting mirror 2 is alpha, wherein 0< alpha is less than or equal to 180 degrees.
Among them, it is preferable that the radius of curvature of the first concave mirror 1 is the same as the radius of curvature of the second concave mirror 2.
The input aperture 11 is disposed at a non-center of the first concave mirror 1 for inputting light.
The exit hole is arranged at the non-center of the first concave reflector 1 and coincides with the incident hole 11, or is arranged at the non-center of the second concave reflector 2 for outputting light.
The middle reflector, the first concave reflector 1 and the second concave reflector 2 form a reflecting cavity for guiding light between the reflecting surface of the first concave reflector 1 and the reflecting surface of the second concave reflector 2.
The incident light enters from the incident hole 11 at an angle non-parallel to the principal axis of the first concave mirror 1, and is reflected multiple times in the reflective cavity and then exits from the exit hole.
Various embodiments of the utility model are illustrated below.
Example 1:
referring to fig. 1, on the basis of the above technical solution, the following implementation is performed:
the first concave reflecting mirror 1 and the second curved reflecting mirror 2 are rectangular concave reflecting mirrors.
The reflecting surface of the first concave reflecting mirror 1 and the reflecting surface of the second concave reflecting mirror 2 are arranged in the same direction,
and the included angle between focal planes of the two concave mirrors is 120 degrees, the number of the middle reflecting mirrors is 2N+1, and N is more than or equal to 0. In this embodiment, the number of intermediate mirrors is 1.
Specifically, the middle reflecting mirror is a plane mirror 3, and the two concave mirrors are symmetrical about the principal axis of the plane mirror 3.
Example 2:
referring to fig. 2, on the basis of the above technical solution, the following implementation is performed:
the first concave reflecting mirror 1 and the second curved reflecting mirror 2 are rectangular concave reflecting mirrors.
The reflecting surface of the first concave reflecting mirror 1 and the reflecting surface of the second concave reflecting mirror 2 are arranged in the same direction, the included angle alpha between focal planes of the two concave reflecting mirrors is 180 degrees, the number of the middle reflecting mirrors is 2N+1, and N is more than or equal to 0. In this embodiment, the number of intermediate mirrors is 1.
Specifically, the middle reflector comprises two plane mirrors 3, the reflecting surfaces of the two plane mirrors 3 are arranged oppositely, and the principal axes of the two plane mirrors are 90 degrees.
Example 3:
referring to fig. 3, on the basis of the above technical solution, the following implementation is performed:
the first concave reflecting mirror 1 and the second curved reflecting mirror 2 are rectangular concave reflecting mirrors.
The reflecting surface of the first concave reflecting mirror 1 and the reflecting surface of the second concave reflecting mirror 2 are arranged in the same direction, the included angle alpha between focal planes of the two concave reflecting mirrors is 180 degrees, the number of the middle reflecting mirrors is 2N+1, and N is more than or equal to 0. In this embodiment, the number of intermediate mirrors is 1.
Specifically, the intermediate reflecting mirror is a prism 4, the cross section of which is an isosceles triangle and the apex angle is 90 °.
Example 4:
referring to fig. 4, on the basis of the above technical solution, the following implementation is performed:
the first concave reflecting mirror 1 and the second curved reflecting mirror 2 are rectangular concave reflecting mirrors.
The reflecting surface of the first concave reflecting mirror 1 and the reflecting surface of the second concave reflecting mirror 2 are arranged in the same direction, the included angle alpha between focal planes of the two concave reflecting mirrors is 180 degrees, the number of the middle reflecting mirrors is 2N+1, and N is more than or equal to 0. In this embodiment, the number of intermediate mirrors is 3.
Specifically, the middle reflector comprises two plane mirrors 3, the reflecting surfaces of the two plane mirrors 3 are arranged oppositely, and the principal axes of the two plane mirrors are 90 degrees.
Example 5:
referring to fig. 5, on the basis of the above technical solution, the following implementation is performed:
the first concave reflecting mirror 1 and the second curved reflecting mirror 2 are round concave reflecting mirrors. In general, the entrance aperture 11 is arranged at the edge of the first concave mirror 1, and the exit Kong Re is arranged on the second concave mirror 2, also at the edge of the second concave mirror 2.
The reflecting surface of the first concave reflecting mirror 1 and the reflecting surface of the second concave reflecting mirror 2 are arranged in the same direction, the included angle alpha between focal planes of the two concave reflecting mirrors is 180 degrees, the number of the middle reflecting mirrors is 2N+1, and N is more than or equal to 0. In this embodiment, the number of intermediate mirrors is 1.
Specifically, the middle reflector comprises two plane mirrors 3, the reflecting surfaces of the two plane mirrors 3 are arranged oppositely, and the principal axes of the two plane mirrors are 90 degrees.
The long-optical-path gas absorption cell is formed into a mirror system by two rectangular concave reflectors and 2N+1 (N is more than or equal to 0) middle reflectors, incident light rays are injected into the mirror system according to a certain angle and are emitted after multiple reflections (the incident light rays form elliptical-like light spot points on different mirrors).
According to the design, the long-optical-path optical gas absorption cell not only can realize the optical path of tens of hundreds of meters in a smaller length, but also has the advantages of high utilization rate of the lens, simple structure, smaller size, easy processing, capability of effectively reducing the cost of the whole gas absorption cell and suitability for a gas analyzer for detecting low-concentration gas.
The utility model also provides a gas sensor, which uses the long-optical-path optical gas absorption cell.
In general, the utility model adopts the two non-coaxial concave reflectors which are arranged in the same direction to form the reflecting cavity by matching with the middle reflector, thus not only realizing longer optical path under the limited volume and meeting the monitoring requirement of low concentration (ppm level or even ppb level) gas, but also having simple structure, small size, easy processing and effectively reducing the cost.
Of course, the above embodiments are only preferred embodiments of the present utility model, and the scope of the present utility model is not limited thereto, so that all equivalent modifications made in the principles of the present utility model are included in the scope of the present utility model.
Claims (10)
1. A long optical path optical gas absorption cell comprising:
a first concave mirror;
a second concave mirror;
the reflecting surface of the first concave reflecting mirror and the reflecting surface of the second concave reflecting mirror are arranged in the same direction, and an included angle between the focal plane of the first concave reflecting mirror and the focal plane of the second concave reflecting mirror is alpha, wherein alpha is more than 0 and less than or equal to 180 degrees;
the input hole is arranged at the non-center of the first concave reflector and is used for inputting light;
an exit aperture for outputting light;
the middle reflector, the first concave reflector and the second concave reflector form a reflecting cavity, and the reflecting cavity is used for guiding light between the reflecting surface of the first concave reflector and the reflecting surface of the second concave reflector;
incident light rays enter the reflecting cavity from the incident hole at an angle which is not parallel to the main axis of the first concave reflecting mirror, and are reflected for many times in the reflecting cavity and then exit from the emergent hole.
2. The long path optical gas absorption cell according to claim 1, wherein the radius of curvature of said first concave mirror is the same as the radius of curvature of said second concave mirror.
3. The long path optical gas absorption cell according to claim 1, wherein said exit aperture is disposed at a non-center of said first concave mirror, and said exit aperture coincides with said entrance aperture.
4. The long path optical gas absorption cell according to claim 1, wherein said exit aperture is disposed at a non-center of said second concave mirror.
5. The long path optical gas absorption cell according to any one of claims 1 to 4, wherein said first concave mirror and said second curved mirror are both rectangular concave mirrors or circular concave mirrors.
6. The long optical path optical gas absorption cell according to claim 1, wherein the number of the intermediate reflectors is 2n+1, n is equal to or greater than 0.
7. The long path optical gas cell of claim 6 wherein said intermediate reflector is a planar mirror.
8. A long path optical gas absorption cell according to claim 6, wherein said intermediate mirror comprises two flat mirrors, the reflecting surfaces of which are disposed opposite each other with the principal axes of both mirrors being 90 °.
9. A long optical path optical gas absorption cell according to claim 6, wherein said intermediate reflector is a prism having a cross section of isosceles triangle and a vertex angle of 90 °.
10. A gas sensor employing a long path optical gas absorption cell according to any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321558309.3U CN220040238U (en) | 2023-06-16 | 2023-06-16 | Long-optical-path optical gas absorption cell and gas sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321558309.3U CN220040238U (en) | 2023-06-16 | 2023-06-16 | Long-optical-path optical gas absorption cell and gas sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220040238U true CN220040238U (en) | 2023-11-17 |
Family
ID=88743709
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202321558309.3U Active CN220040238U (en) | 2023-06-16 | 2023-06-16 | Long-optical-path optical gas absorption cell and gas sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220040238U (en) |
-
2023
- 2023-06-16 CN CN202321558309.3U patent/CN220040238U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8508740B2 (en) | Optical multi-pass cell | |
| CN101477044B (en) | Surface plasma resonance sensor | |
| WO2016095816A1 (en) | Sample measurement pool | |
| CN203132991U (en) | Movable-part-free multichannel angle modulation type surface plasmon resonance (SPR) sensor detection system | |
| US7215428B2 (en) | Absorption spectroscopy apparatus and method | |
| JP2017187468A (en) | Multireflection cell, analyzer, exhaust gas analyzer, and light incident method | |
| US9323035B2 (en) | Annular optical device | |
| CN113340837B (en) | Long-optical-path miniature infrared air chamber and infrared gas sensor | |
| CN211697465U (en) | Optical absorption cell and photoelectric gas analyzer | |
| CN204314209U (en) | sample measuring cell | |
| EP1853897B1 (en) | Gas cell using two parabolic concave mirrors and method of producing gas sensor using the same | |
| CN113484266B (en) | Optical path multiplying device and optical path multiplying gas absorption cell | |
| CN220040238U (en) | Long-optical-path optical gas absorption cell and gas sensor | |
| CN116858504B (en) | Optical axis monitoring system | |
| CN116660165A (en) | Long-optical-path optical gas absorption cell and gas sensor | |
| CN114609044B (en) | Long-optical-path gas absorption cell reflection optical system | |
| CN105784593A (en) | Quadruplet objective lens Chernin type multi-optical-distance gas absorption cavity | |
| JP3151670U (en) | Gas cell | |
| CN210071648U (en) | Triple optical path air chamber and gas detection equipment | |
| US20180088038A1 (en) | Gas detection device | |
| CN219369553U (en) | Long optical path absorption cell structure | |
| CN211402104U (en) | Long-optical-path gas absorption cell with isolation gas circuit | |
| CN220064429U (en) | Long-distance direct coupling type optical fiber coupling module | |
| CN215375079U (en) | Compact multi-reflection gas absorption cell and compact infrared sensor | |
| CN220019299U (en) | Light path system for enhancing light intensity of photosensitive area through multiple reflection |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |