Optical Path Coupling Mechanism of Gas Analyzer

Abstract

The present invention provides an optical path coupling mechanism for a gas analyzer, comprising a sealed cavity, one side of which is provided with an interferometer light input interface for sealing connection with the interferometer; the other side of the sealed cavity is provided with a gas pool incident sealing interface and a gas pool exit sealing interface, respectively used for sealing connection with the gas pool; an exit off-axis parabolic mirror, an incident off-axis parabolic mirror and a transfer off-axis parabolic mirror are arranged in the sealed cavity; the exit off-axis parabolic mirror can reflect and transform parallel light entering from the interferometer light input interface into convergent light, and enter the gas pool from the gas pool incident sealing interface; the incident off-axis parabolic mirror can reflect and transform light entering the sealed cavity from the gas pool exit sealing interface into parallel light; the transfer off-axis parabolic mirror can converge the parallel light reflected by the incident off-axis parabolic mirror to a detector arranged in the sealed cavity. The present invention has a short optical path, compact size, convenient debugging and high optical coupling efficiency.

Description

Technical Field

[0001] The invention relates to an optical path coupling mechanism in a gas analyzer, which is a key component in the gas analyzer. Background Art

[0002] The gas analyzer is composed of an infrared interferometer, a gas cell, a gas path system, an optical path coupling system, a detector module, etc. The infrared interferometer and the gas cell are independent components of the instrument. The infrared interferometers of various companies are all deformations of the Michelson interferometer. Although they have different shapes, their performance indicators are roughly the same. The gas cell uses a White cell with different optical paths. The optical path coupling system is the link between the interferometer and the gas cell. The quality of the optical path coupling mechanism design directly affects the indicators and performance of the instrument.

[0003] Existing optical coupling systems are generally arranged horizontally, which greatly increases the distance between the interferometer and the gas pool, making the overall structure bloated. Summary of the invention

[0004] The invention provides an optical path coupling mechanism of a gas analyzer, which adopts a new layout form, has a compact structure, a small volume, is easy to debug, and has good sealing performance.

[0005] The technical solution adopted by the present invention is:

[0006] An optical path coupling mechanism for a gas analyzer, characterized in that it comprises a sealed cavity, one side of the sealed cavity is provided with an interferometer light input interface for sealed connection with the interferometer; the other side of the sealed cavity is provided with a gas pool incident sealing interface and a gas pool exit sealing interface, respectively used for sealed connection with the gas pool; wherein:

[0007] An outgoing off-axis parabolic mirror, an incident off-axis parabolic mirror and a transfer off-axis parabolic mirror are arranged in the sealed cavity;

[0008] The output off-axis parabolic mirror can reflect and transform the parallel light entering from the light input interface of the interferometer into convergent light, and enter the gas pool through the gas pool incident sealing interface;

[0009] The incident off-axis parabolic mirror can transform the light reflection entering the sealed cavity from the gas pool outlet sealed interface into parallel light;

[0010] The switching off-axis parabolic mirror can converge the parallel light reflected by the incident off-axis parabolic mirror onto the detector arranged in the sealed cavity.

[0011] The optical path coupling mechanism of the gas analyzer, wherein the interferometer light input interface is arranged along a horizontal longitudinal direction, and the gas pool incident sealing interface and the gas pool exit sealing interface are arranged along a horizontal transverse direction;

[0012] The exit off-axis parabolic mirror, the upper part of the incident off-axis parabolic mirror, and the transfer off-axis parabolic mirror are arranged at different heights.

[0013] In the optical path coupling mechanism of the gas analyzer, the positions of the outgoing off-axis parabolic mirror and the incident off-axis parabolic mirror are relatively fixed, and can be moved horizontally relative to the sealed cavity through the parabolic mirror slide rail.

[0014] The optical path coupling mechanism of the gas analyzer, wherein the transition off-axis parabolic mirror can move vertically relative to the sealed cavity.

[0015] The optical path coupling mechanism of the gas analyzer, wherein the adapter off-axis parabolic mirror is fixed to a guide rail seat, the guide rail seat is connected to a fixed seat via a vertical guide rail, the fixed seat is fixed to a sealed cavity, a fixed guide rail knob is provided on the guide rail seat, and the guide rail knob is connected to the fixed seat via a threaded connection.

[0016] The optical path coupling mechanism of the gas analyzer, wherein the detector can adjust its position relative to the sealed cavity in the horizontal longitudinal direction and the horizontal lateral direction.

[0017] The optical path coupling mechanism of the gas analyzer is characterized in that the detector is fixed to the detector bracket, the detector bracket is installed on the detector seat through a longitudinal slide rail, and the detector seat is installed in the sealed cavity through a transverse slide rail.

[0018] The optical path coupling mechanism of the gas analyzer, wherein the pitch of the guide knob is less than or equal to 0.25 mm.

[0019] The optical path coupling mechanism of the gas analyzer is characterized in that a barium fluoride exit window and a barium fluoride incident window are respectively provided at the gas pool incident sealing interface and the gas pool exit sealing interface.

[0020] The optical path coupling mechanism of the gas analyzer is characterized in that a calcium fluoride window is installed at the light input interface of the interferometer.

[0021] The optical path of the present invention is short, and the microenvironment is stable through the sealing design, and the interference of environmental factors is small. In addition, the present invention has a simple structure, a compact size, convenient debugging, and high optical coupling efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is an overall stereoscopic diagram of the optical path coupling cavity.

[0023] Figure 2 This is the overall main view of the optical path coupling cavity.

[0024] Figure 3 This is the overall left view of the optical coupling cavity.

[0025] Figure 4 This is the right view of the internal optical path structure.

[0026] Figure 5 It is the main view of the internal optical path structure.

[0027] Figure 6 It is the left view of the internal optical path structure.

[0028] Figure 7 It is a three-dimensional diagram of the internal optical path structure.

[0029] Explanation of the reference numerals: 1-gas pool exit sealing interface; 2-gas pool incident sealing interface; 3-interferometer light input interface; 4-upper cover; 5-sealed cavity; 6-base; 7-barium fluoride exit window; 8-barium fluoride incident window; 9-parabolic mirror bracket 2; 10-incident off-axis parabolic mirror; 11-transfer off-axis parabolic mirror, 12-exit off-axis parabolic mirror; 13-detector housing; 14-detector; 15-detector bracket; 16-longitudinal slide rail; 17-detector seat; 18-lateral slide rail; 19-parabolic mirror bracket; 20-parabolic mirror slide rail; 21-knob; 22-guide rail seat; 23-vertical guide rail; 24-fixed seat. DETAILED DESCRIPTION

[0030] The invention provides an optical path coupling mechanism of a gas analyzer, which can couple an interferometer, a gas cell and a detector module into a whole. The optical coupling mechanism has a compact structure, a small volume, convenient debugging and good sealing performance.

[0031] like Figure 1-Figure 3 As shown, it is a three-dimensional view, a front view and a left view of the optical path coupling mechanism of the gas analyzer of the present invention, which mainly includes a sealed cavity 5, the top surface of the sealed cavity 5 is sealed with an upper cover 4, the bottom surface is sealed with a base 6, and the front surface ( Figure 2 The side of the sealed cavity 5 (facing the reader) is provided with an interferometer light input interface 3 and a calcium fluoride window (the sealing interface material is preferably a heat-resistant and stable material Peek) for sealing connection with the interferometer; the side of the sealed cavity 5 ( Figure 2 The left side of the gas pool is provided with a gas pool incident sealing interface 2 and a gas pool exit sealing interface 1, which are respectively used to be sealed and connected with the gas pool incident window and the gas pool exit window, and the gas pool incident sealing interface 2 and the gas pool exit sealing interface 1 are respectively provided with a barium fluoride exit window 7 and a barium fluoride incident window 8; a detector 14 is provided inside the sealed cavity 5;

[0032] When using (with Figure 2 , Figure 4As shown in the figure, the horizontal longitudinal parallel light coming out of the interferometer enters the sealed cavity 5 through the interferometer light input interface 3 of the sealed cavity 5, is transformed into horizontal transverse convergent light through the 90° reflection of the off-axis parabolic mirror 12, enters the gas pool through the gas pool incident sealing interface 2, is reflected multiple times by the gas pool, enters the sealed cavity 5 again along the horizontal transverse direction from the gas pool exit sealing interface 1, is transformed into vertical parallel light through the 90° upward reflection of the incident off-axis parabolic mirror 10, and is transformed into horizontal transverse convergent light through the 90° reflection of the switching off-axis parabolic mirror 11, and converges on the detector 14.

[0033] The present invention arranges the gas pool incident sealing interface 2 and the gas pool exit sealing interface 1 in an upper and lower layout, and arranges the exit off-axis parabolic mirror 12, the incident off-axis parabolic mirror 10, and the transfer off-axis parabolic mirror 11 on the same vertical line, which can reduce the volume of the entire optical path coupling structure and make the structure compact.

[0034] For example Figure 4 , Figure 5 , Figure 6 , Figure 7 As shown, they are the right view, main view, left view and stereogram of the internal optical path structure, and we can see:

[0035] The outgoing off-axis parabolic mirror 12 and the incident off-axis parabolic mirror 10 are mounted on a parabolic mirror bracket 19. The parabolic mirror bracket 19 can move horizontally relative to the base 6 through a parabolic mirror slide rail 20 made of polytetrafluoroethylene material to achieve optical focusing and connection between the interferometer and the gas pool in the horizontal direction.

[0036] The transfer off-axis parabolic mirror 11 is fixed to the guide rail seat 22 through a support plate. The guide rail seat 22 is connected to the fixed seat 24 through a vertical guide rail 23. The fixed seat 24 is fixed to the base 6, so that the guide rail seat 22 and the transfer off-axis parabolic mirror 11 thereon can move vertically relative to the base 6. A fixed guide rail knob 21 is provided on the guide rail seat 22. The guide rail knob 21 is connected to the fixed seat 24 through a thread. By rotating the guide rail knob 21, the vertical position of the transfer off-axis parabolic mirror 11 can be adjusted to achieve vertical optical focusing of the transfer off-axis parabolic mirror 11 and the detector 14.

[0037] Among them, the detector 14 is fixed to the detector shell 13, the detector shell 13 is fixed to the detector bracket 15, the detector bracket 15 is installed on the detector seat 17 through the longitudinal slide rail 16, and the detector seat 17 is installed on the base 6 through the transverse slide rail 18; by means of horizontal adjustment of the longitudinal slide rail 16 and the transverse slide rail 18, the optical focusing of the off-axis parabolic mirror 11 and the detector 14 in the horizontal longitudinal and horizontal directions can be realized.

[0038] The thread on the guide knob 21 is a precision thread with a pitch of 0.25 mm, which can ensure the optical coupling accuracy of the sensitive element on the detector 14 .

[0039] The barium fluoride exit window 7 and the barium fluoride incident window 8 are used as sealing windows, taking into account both the infrared transmittance (the transmittance can reach 96%) and the infrared waveband range (2.5um-20um).

[0040] In summary, the optical path of the present invention is short, and the microenvironment is stable through the sealing design, and the interference of environmental factors is small. In addition, the present invention has a simple structure, a compact size, convenient debugging, and high optical coupling efficiency.

Claims

1. An optical path coupling mechanism for a gas analyzer, characterized in that: It comprises a sealed cavity, one side of which is provided with an interferometer light input interface for sealing connection with the interferometer; the other side of the sealed cavity is provided with a gas pool incident sealing interface and a gas pool exit sealing interface, which are respectively used for sealing connection with the gas pool; wherein: An outgoing off-axis parabolic mirror, an incident off-axis parabolic mirror and a transfer off-axis parabolic mirror are arranged in the sealed cavity; The output off-axis parabolic mirror can reflect and transform the parallel light entering from the light input interface of the interferometer into convergent light, and enter the gas pool through the gas pool incident sealing interface; The incident off-axis parabolic mirror can transform the light reflection entering the sealed cavity from the gas pool outlet sealed interface into parallel light; The switching off-axis parabolic mirror can converge the parallel light reflected by the incident off-axis parabolic mirror onto the detector arranged in the sealed cavity.

2. The optical path coupling mechanism of the gas analyzer according to claim 1, characterized in that: The interferometer light input interface is arranged along a horizontal longitudinal direction, and the gas pool incident sealing interface and the gas pool exit sealing interface are arranged along a horizontal transverse direction; The exit off-axis parabolic mirror, the upper part of the incident off-axis parabolic mirror, and the transfer off-axis parabolic mirror are arranged at different heights.

3. The optical path coupling mechanism of the gas analyzer according to claim 2, characterized in that: The exit off-axis parabolic mirror and the incident off-axis parabolic mirror are relatively fixed in position and can move horizontally relative to the sealed cavity through the parabolic mirror slide rail.

4. The optical path coupling mechanism of the gas analyzer according to claim 1 or 3, characterized in that: The transition off-axis parabolic mirror can move vertically relative to the sealed cavity.

5. The optical path coupling mechanism of the gas analyzer according to claim 4, characterized in that: The transfer off-axis parabolic mirror is fixed to the guide rail seat, the guide rail seat is connected to the fixing seat through the vertical guide rail, the fixing seat is fixed to the sealing cavity, and a fixed guide rail knob is provided on the guide rail seat, and the guide rail knob is connected to the fixing seat through threads.

6. The optical path coupling mechanism of the gas analyzer according to claim 4, characterized in that: The position of the detector can be adjusted relative to the sealed cavity in the horizontal longitudinal direction and the horizontal lateral direction.

7. The optical path coupling mechanism of the gas analyzer according to claim 6, characterized in that: The detector is fixed to the detector bracket, the detector bracket is installed on the detector seat through a longitudinal slide rail, and the detector seat is installed in the sealed cavity through a transverse slide rail.

8. The optical path coupling mechanism of the gas analyzer according to claim 5, characterized in that: The pitch of the guide rail knob is less than or equal to 0.25 mm.

9. The optical path coupling mechanism of the gas analyzer according to claim 1, characterized in that: A barium fluoride exit window and a barium fluoride incident window are respectively arranged at the gas pool incident sealing interface and the gas pool exit sealing interface.

10. The optical path coupling mechanism of the gas analyzer according to claim 1, characterized in that: Install a calcium fluoride window at the light input interface of the interferometer.

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