Optical cavity structure for high resolution laser gas sensor

Abstract

The utility model discloses a high resolution laser gas sensor's optical cavity structure, including shell, and install laser emitter and laser receiver in the shell in the shell, the shell includes the cylindrical casing and is connected and is blocked first cover plate, second cover plate at both ends, and first cover plate has the central hole, and the central hole installs the threaded mouth, and the threaded mouth is used for the signal line of optical fiber and and pd output, install the support between first cover plate and second cover plate, and the end of support is installed laser emitter close to threaded mouth, and the other end of support installs laser receiver, and the space between both sides on support is detection channel. The utility model has the beneficial effects that realize small size, high stability light path and the performance of anti-absorption and anti-residual, thereby improve the detection precision and response speed of sensor.

Description

Technical Field

[0001] This invention relates to the field of gas sensor technology, specifically to an optical cavity structure for a high-resolution laser gas sensor. Background Technology

[0002] In laser gas sensors, the structure of the optical cavity plays a crucial role in the sensor's performance. Traditional optical cavities suffer from problems such as large size, insufficient optical path stability, and measurement errors caused by gas adsorption and residue. With the increasing demands for accuracy, miniaturization, and rapid response in gas sensors, a novel optical cavity structure is needed to address these issues. Summary of the Invention

[0003] To overcome the shortcomings of existing technologies, this invention provides an optical cavity structure for a high-resolution laser gas sensor, achieving a small size, a highly stable optical path, and resistance to adsorption and residue, thereby improving the sensor's detection accuracy and response speed.

[0004] This utility model is achieved through the following technical solution: The optical cavity structure of the high-resolution laser gas sensor of this utility model is characterized by: including a housing, and a laser emitter and a laser receiver installed inside the housing; The housing includes a cylindrical shell and a first cover plate and a second cover plate connected and sealed at both ends thereto. The first cover plate has a central hole and a threaded port is installed at the central hole. The threaded port is used for optical fiber and signal line output by PD. A bracket is installed between the first cover plate and the second cover plate. A laser emitter is installed on one end of the bracket near the threaded opening, and a laser receiver is installed on the other end of the bracket. The space between the two on the bracket is the detection channel.

[0005] More preferably, the optical cavity is an elliptical optical cavity, that is, the axial cross-section of the cylindrical shell is elliptical, with a thicker middle and thinner ends.

[0006] Alternatively, the optical cavity can be a hyperbolic optical cavity, meaning that the axial section of the cylindrical shell is a concave hyperbola, which is thinner in the middle and thicker at both ends.

[0007] Further preferably, the housing has a large number of elongated through holes and a large number of circular through holes to increase the gas intake for gas detection and improve the accuracy of gas detection concentration.

[0008] A further preferred embodiment has a filter screen attached to the inside of the housing for dust prevention.

[0009] More preferably, the bracket includes a first plate, a second plate, a third plate, and a fourth plate. The left ends of each plate are fixed together by a first fastener, and the right ends of each plate are fixed together by a second fastener. The first fastener is fixed to the first cover plate by a left ear plate, and the second fastener is fixed to the second cover plate by a right ear plate. The laser emitter is mounted on the first fixture, and the laser receiver is mounted on the second fixture. The laser emitter and laser receiver are located between the three-layer board and the four-layer board, and the space between the three-layer board and the four-layer board is the detection channel.

[0010] More preferably, the inner sides of the shell, the first cover plate, and the second cover plate are coated with a titanium dioxide nano-coating.

[0011] Preferably, the inner sides of the housing, the first cover plate, and the second cover plate are made of quartz glass.

[0012] The beneficial effects of this utility model are: 1. Small size: By optimizing the geometry and using new materials, the optical cavity is elliptical or concave hyperbolic in shape, and the material is specially treated quartz glass or specific polymer materials, which realizes the small volume design of the optical cavity, meets the needs of sensor miniaturization, and can be widely used in various scenarios with limited space, such as portable gas detection equipment. 2. Stable optical path: The special geometry and material properties ensure the high stability of the optical path, reduce the impact of external environmental interference on the optical path, and improve the measurement accuracy and reliability of the sensor. 3. Anti-adsorption and anti-residue: The titanium dioxide nano-coating and optimized gas flow channels effectively reduce gas adsorption and residue, improve the sensor's response speed and accuracy, and enable the sensor to detect changes in gas concentration quickly and accurately. Attached Figure Description

[0013] The attached figure is a schematic diagram of the front view of this utility model.

[0014] Figure 1 , Figure 2 This is an external view and a cross-sectional view of an elliptical optical cavity. Figure 3 , Figure 4 The diagram shows the external shape and cross-sectional view of the concave hyperbolic optical cavity.

[0015] In the diagram: 1. Threaded opening; 2. Housing; 3. First cover plate; 4. Second cover plate; 5. Elongated through hole; 6. Bracket; 7. Laser emitter; 8. Laser receiver; 9. Filter screen; 10. Detection channel; 11. First fixing component; 12. Second fixing component; 13. Circular through hole. Detailed Implementation

[0016] The attached figure shows a specific embodiment of this utility model.

[0017] The optical cavity structure of the high-resolution laser gas sensor of this invention includes a housing, and a laser emitter 7 and a laser receiver 8 installed inside the housing; The outer casing includes a cylindrical shell 2 and a first cover plate 3 and a second cover plate 4 connected and sealed at both ends thereto. The first cover plate has a central hole, and a threaded port 1 is installed at the central hole. The threaded port is used for optical fiber and signal line output by PD. A bracket 6 is installed between the first cover plate 3 and the second cover plate 4. A laser emitter 7 is installed on one end of the bracket near the threaded opening, and a laser receiver 8 is installed on the other end of the bracket. The space between the two on the bracket is a detection channel 10.

[0018] The optical cavity adopts an elliptical optical cavity, that is, the axial section of the cylinder of the shell 2 is elliptical, with a thicker middle and thinner ends.

[0019] Alternatively, the optical cavity can be a hyperbolic optical cavity, that is, the axial section of the cylinder of the shell 2 is a hyperbolic shape that is concave inward, with a thinner middle and thicker ends.

[0020] The housing 2 has a large number of elongated through holes 5 and a large number of circular through holes 13, which are used to increase the gas intake for gas detection and improve the accuracy of gas detection concentration.

[0021] A filter screen 9 is attached to the inside of the housing for dust prevention.

[0022] The bracket 6 includes a first plate 14, a second plate 15, a third plate 16, and a fourth plate 17. The left ends of each plate are fixed together by a first fastener 11, and the right ends of each plate are fixed together by a second fastener 12. The first fastener is fixed to the first cover plate 3 by a left ear plate 18, and the second fastener is fixed to the second cover plate 4 by a right ear plate 18. The laser emitter is mounted on the first fixture, and the laser receiver is mounted on the second fixture. The laser emitter 7 and the laser receiver 8 are located between the three-layer plate 16 and the four-layer plate 17, and the space between the three-layer plate and the four-layer plate is the detection channel 10.

[0023] The inner sides of the shell 2 and the first cover plate 3 and the second cover plate 4 at both ends are coated with a titanium dioxide nano-coating.

[0024] The inner sides of the shell and the first and second cover plates at both ends are made of quartz glass.

[0025] Optical cavity design: A special geometric design is employed, specifically an elliptical or hyperbolic cavity. Compared to traditional rectangular or cylindrical cavities, this design more effectively converges and reflects light, increases the optical path, and improves the efficiency of gas-light interaction. For example, the designed elliptical optical cavity has a major axis of [X] mm and a minor axis of [Y] mm. Simulations and experiments have verified that, for the same volume, the optical path is increased compared to a traditional cylindrical optical cavity. Material selection: Materials with low refractive index, low dispersion, and good anti-adsorption properties are selected, such as specially treated quartz glass or specific polymer materials. Taking a novel polymer material as an example, its surface energy is lower than that of ordinary optical materials, effectively reducing gas adsorption on the cavity wall. Anti-adsorption and anti-residue technology: Nano-coating technology is employed inside the optical cavity, such as coating a titanium dioxide nano-coating with a thickness of [nano-thickness value], utilizing its photocatalytic properties to decompose adsorbed gas molecules. Simultaneously, the gas flow channels inside the cavity are optimized, employing microfluidic technology to design unique gas inlet and outlet structures, enabling uniform and rapid gas flow within the cavity and reducing gas residue. For example, the designed microfluidic gas inlet and outlet structure (i.e., numerous elongated and circular through-holes) allows gas to fill the entire optical cavity within 1 second with minimal residue.

[0026] Optical cavity fabrication: High-precision processing equipment, such as femtosecond laser processing machines, is used to process the selected material according to the designed geometry. For optical cavities employing nano-coatings, after fabrication, a nano-coating is uniformly coated onto the inner surface of the cavity using methods such as chemical vapor deposition.

[0027] Gas flow channel installation: The designed microfluidic gas inlet and outlet structure (i.e., numerous elongated and circular through-holes) is precisely assembled with the optical cavity to ensure smooth gas flow and airtightness. During assembly, sealant and other materials are used for sealing to prevent gas leakage. Sensor Integration: The fabricated optical cavity is integrated with other sensor components such as the laser source and detector to form a complete laser gas sensor. During the integration process, it is essential to ensure the stability of the optical alignment and electrical connections between the various components.

Claims

1. An optical cavity structure for a high-resolution laser gas sensor, characterized in that: Includes the housing, and the laser emitter and laser receiver installed inside the housing; The housing includes a cylindrical shell and a first cover plate and a second cover plate connected and sealed at both ends thereto. The first cover plate has a central hole and a threaded port is installed at the central hole. The threaded port is used for optical fiber and signal line output by PD. A bracket is installed between the first cover plate and the second cover plate. A laser emitter is installed on one end of the bracket near the threaded opening, and a laser receiver is installed on the other end of the bracket. The space between the two on the bracket is the detection channel.

2. The optical cavity structure of the high-resolution laser gas sensor according to claim 1, characterized in that: The optical cavity is elliptical, meaning the axial cross-section of the cylindrical shell is elliptical, thicker in the middle and thinner at both ends.

3. The optical cavity structure of the high-resolution laser gas sensor according to claim 1, characterized in that: The optical cavity adopts a hyperbolic shape, that is, the axial section of the cylindrical shell is a hyperbolic shape that is concave inward, with a thinner middle and thicker ends.

4. The optical cavity structure of the high-resolution laser gas sensor according to any one of claims 1-3, characterized in that: The housing has a large number of elongated through holes and a large number of circular through holes to increase the gas intake and improve the accuracy of gas concentration detection.

5. The optical cavity structure of the high-resolution laser gas sensor according to any one of claims 1-3, characterized in that: A filter screen is attached to the inside of the housing for dust prevention.

6. The optical cavity structure of the high-resolution laser gas sensor according to any one of claims 1-3, characterized in that: The bracket includes a first layer, a second layer, a third layer, and a fourth layer. The left ends of each layer are fixed together by a first fastener, and the right ends of each layer are fixed together by a second fastener. The first fastener is fixed to the first cover plate by a left ear plate, and the second fastener is fixed to the second cover plate by a right ear plate. The laser emitter is mounted on the first fixture, and the laser receiver is mounted on the second fixture. The laser emitter and laser receiver are located between the three-layer board and the four-layer board, and the space between the three-layer board and the four-layer board is the detection channel.

7. The optical cavity structure of the high-resolution laser gas sensor according to claim 1, characterized in that: The inner sides of the shell and the first and second cover plates at both ends are coated with a titanium dioxide nano-coating.

8. The optical cavity structure of the high-resolution laser gas sensor according to claim 1, characterized in that: The shell and the first and second cover plates at both ends are made of quartz glass.

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