Wavelength self-alignment laser for gas detection

Abstract

The utility model provides a wavelength self-alignment laser for gas detection. The wavelength self-alignment laser comprises a laser tube shell, and a light emitting assembly, a light splitting sheet and a detection detector which are packaged in the laser tube shell, the laser tube shell is provided with a measuring light beam emitting hole, the light splitting piece is located on an emitting light path of the light emitting assembly and divides the emitting light path into a first light splitting path and a second light splitting path, and the detection detector and the measuring light beam emitting hole are located on the first light splitting path and the second light splitting path respectively. A sealing transmission lens is arranged between the detection detector and the beam splitter; and a detector encapsulation coupling tube body is sleeved on the upper end surface of the brim of a tube cap of the detection detector. According to the utility model, a series of technical problems of equipment false alarm caused by poor air tightness of a wavelength self-alignment laser used by a conventional gas real-time online detector and high cost caused by large difference between an internal laser structure and an optical link of gas real-time online detectors used under different working conditions are solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of TDLAS gas detection, and in particular relates to a wavelength self-aligning laser for gas detection. Background Art

[0002] TDLAS technology (Tunable Diode Laser Absorption Spectroscopy) is based on a tunable diode laser and utilizes the "frequency-selective" characteristics of the gas molecules being measured to measure the characteristics of the gas being measured. The "frequency-selective" nature of gas molecules on light waves avoids cross-interference from other unrelated gas components, making it the preferred solution for accurate real-time online gas detection systems. Its fast response speed, low measurement limit, and self-calibration make it particularly suitable for measuring hazardous gases, including methane, carbon monoxide, carbon dioxide, oxygen, ammonia, hydrogen sulfide, and other gases. Since the late 1990s, gas detection solutions and equipment based on TDLAS technology have emerged in large numbers, and a variety of measurement methods have emerged in industrial applications, including fixed test systems, distributed test systems, and telemetry test systems.

[0003] Due to the different on-site working conditions in industrial applications, the required TDLAS online detection instruments also work slightly differently. For example, the distributed methane gas detectors used in coal mining use a one-to-many fiber optic connection architecture between the laser light source and the detection gas chamber to meet the layout requirements of a star network. Another example is a fixed diffusion gas detector that integrates the laser and the gas chamber together, passing a collimated light beam through the gas chamber to reach the opposite detector. Another example is a remote sensing gas detector that needs to detect the target gas concentration in a large area, so the laser light source needs to have a fixed divergence angle to meet the working condition requirement of the conical beam covering a specified area.

[0004] The existing devices for online gas detection using TDLAS technology have the following major technical problems:

[0005] (1) The wavelength self-aligning laser used in the current real-time online detectors on the market may cause the target gas sample sealed inside the detector to leak into the laser measurement optical path, resulting in the problem of false alarm of the online detection equipment. Such problems will cause huge management losses in special working conditions such as coal mines.

[0006] (2) The wavelength self-aligning lasers currently used in real-time online detectors on the market cannot achieve the application of the same structure in multiple working conditions. The wavelength self-aligning lasers with collimated beam output, convergent optical fiber output, and specific divergent angle cone spot output are often not uniform in structure and cannot be standardized and mass-produced, resulting in high costs. Utility Model Content

[0007] The purpose of the utility model is to provide a wavelength self-aligning laser for gas detection, which can at least solve some of the defects in the prior art.

[0008] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0009] A wavelength self-aligning laser for gas detection comprises a laser tube shell, and a light emitting assembly, a beam splitter, and a detector detector encapsulated in the laser tube shell; the laser tube shell is provided with a measuring light beam exit hole, the beam splitter is located on the exit light path of the light emitting assembly and divides the exit light path into a first split light path and a second split light path, the detector detector and the measuring beam exit hole are located on the first split light path and the second split light path, respectively, a sealed transmission lens is provided between the detector detector and the beam splitter, a detector potting coupling tube body is fitted on the upper end face of the tube cap brim of the detector detector, and a target gas sample to be measured is sealed in the detector detector.

[0010] Furthermore, the light emitting component is a collimated light emitting component, a convergent light emitting component or a divergent light emitting component.

[0011] Furthermore, the light emitting component and the detection detector are placed opposite to each other, in the same direction, or sideways.

[0012] Furthermore, when the light emitting assembly and the detection detector are placed in the same direction, a total reflection lens is provided between the beam splitter and the detection detector, and the total reflection lens is placed opposite to the beam splitter.

[0013] Furthermore, the beam splitter has a first surface and a second surface, the first surface is coated with a narrowband semi-transmissive and semi-reflective film, and the second surface is coated with an AR anti-reflection film.

[0014] Furthermore, an external optical isolator is fixedly installed at the measuring light beam exit hole.

[0015] Furthermore, an optical fiber coupling component for coupling and fixing an optical fiber is fixedly installed at the measuring beam exit hole, and the second light splitting path of the light splitting plate is coupled into the optical fiber.

[0016] Furthermore, the light emitting end of the light emitting component is coaxially provided with a built-in optical isolator.

[0017] Furthermore, the light emitting component is a coaxially packaged laser device with a semiconductor refrigeration module.

[0018] Furthermore, the wavelength self-aligning laser for gas detection further comprises an L-shaped heat sink fixed on the laser tube shell, and one side of the L-shaped heat sink is fixed to the heat dissipation surface at the bottom of the light emitting component.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) The wavelength self-aligning laser provided by the present invention adopts a detector potting coupling tube body to seal the original TO tube cap, tube seat welding seal, and TO tube seat PIN needle glass metal seal of the detector detector again, thereby providing double-layer sealing protection for the airtight seal of the product, greatly reducing the possibility of leakage of the target gas sample in the detector detector; at the same time, a sealed transmission lens is provided in front of the light incident port of the detector detector, so that the detector detector is completely regionally isolated in the laser tube shell without affecting the reception of the detection light beam, thereby structurally eliminating the problem of the target gas sample potted inside the detector detector leaking into the laser measurement light path, causing the online detection equipment to falsely alarm.

[0021] (2) The wavelength self-aligning laser provided by the present invention can use light emitting components with different light beam output forms when other structural components and assembly methods remain unchanged, thereby achieving the purpose of variable output beam of the self-aligning laser, unifying the wavelength self-aligning laser structures of collimated beam output, convergent optical fiber output, and specific divergent angle cone spot output under various working conditions, realizing standardized mass production, and reducing manufacturing costs.

[0022] The present invention will be described in further detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the wavelength self-aligning laser structure in which the light emitting component in Example 1 of the present utility model adopts a collimated light emitting component;

[0024] Figure 2 Schematic diagram of the wavelength self-aligned laser structure in which the light emitting component adopts a divergent light emitting component in Example 2 of the present utility model;

[0025] Figure 3 Schematic diagram of the structure of a wavelength self-aligned laser in which the light emitting component in Example 3 of the present utility model adopts a convergent light emitting component;

[0026] Figure 4 This is a schematic diagram of the wavelength self-aligning laser structure in which the light emitting component and the detection detector are placed opposite to each other in Example 4 of the present utility model;

[0027] Figure 5This is a schematic diagram of the wavelength self-aligning laser structure in which the light emitting component and the detection detector are placed in the same direction in Example 5 of the present utility model.

[0028] Explanation of the accompanying symbols: 1. Light emitting component; 2. Laser tube shell; 3. Beam splitter; 4. External optical isolator; 5. Sealed transmission lens; 6. Detection detector; 7. Detector potting coupling tube body; 8. L-shaped heat sink; 9. Built-in optical isolator; 10. Optical fiber coupling; 11. Optical fiber; 12. Total reflection lens. DETAILED DESCRIPTION

[0029] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0031] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "install", "connect" and "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, a conflicting connection or an integral connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the technical features indicated. Therefore, features specified as "first" or "second" may explicitly or implicitly include one or more of such features; and in the description of this utility model, unless otherwise specified, "plurality" means two or more.

[0033] Example 1:

[0034] like Figure 1As shown, this embodiment provides a wavelength self-aligning laser for gas detection, including a laser tube shell 2, and a light emitting component 1, a beam splitter 3 and a detector detector 6 encapsulated in the laser tube shell 2; the laser tube shell 2 is provided with a measurement beam exit hole, the beam splitter 3 is located on the exit light path of the light emitting component 1, and divides the exit light path into a first split light path and a second split light path, the detector detector 6 and the measurement beam exit hole are respectively located in the first split light path and the second split light path, a sealed transmission lens 5 is provided between the detector detector 6 and the beam splitter 3, the upper end face of the tube cap brim of the detector detector 6 is fitted with a detector potting coupling tube body 7, and the target gas sample to be measured is sealed in the detector detector 6. In this embodiment, the light emitting component 1 is lasered in the laser tube shell 2. At the beam splitter 3, the laser beam is split into two, one beam is used for measuring beam output and is output from the measuring beam exit hole, and the other beam is output as the detection beam. The detection detector 6 receives and analyzes the change in the center wavelength of the detection beam, and controls the temperature of the light emitting component 1 so that the center wavelength of the measurement beam is aligned with the center wavelength of the target gas to be measured. In order to prevent the target gas sample to be measured encapsulated in the detection detector 6 from leaking into the laser measurement optical path, this embodiment uses a detector encapsulation coupling tube 7 to connect the detection detector 6 to the laser. The original TO tube cap, tube base welding seal, and TO tube base PIN needle glass metal seal are re-sealed with tube glue to provide double-layer sealing protection for the product's airtight seal, greatly reducing the possibility of leakage of the target measured gas sample in the detection detector 6; at the same time, a sealed transmission lens 5 is provided in front of the light incident port of the detection detector 6, so that the detection detector 6 can physically isolate the measurement optical path and the detection optical path without affecting the reception of the detection light beam, thereby structurally eliminating the problem of false alarm of the online detection equipment due to the leakage of the target measured gas sample encapsulated inside the detection detector 6 into the laser measurement optical path.

[0035] In a specific embodiment, the light emitting component 1 adopts a collimated light emitting component, which is a coaxially packaged laser device with a semiconductor refrigeration module; specifically, the collimated light emitting component can adopt, but is not limited to, a TO-packaged DFB laser (distributed feedback laser) with a TEC (semiconductor refrigeration module), and has a built-in collimating lens, and the output light beam is a collimated light beam. The target gas sample sealed in the detection detector 6 can be, but is not limited to, methane gas. The detection wavelength used by the laser selected for the light emitting component 1 should correspond to the type of target gas to be measured in the detection detector. For example, when the target gas to be measured in the detection detector 6 is methane gas, the TEC peak wavelength of the DFB laser selected for the collimated light emitting component is 1653.7nm.

[0036] Specifically, such as Figure 1As shown, the light emitting assembly 1 utilizes a collimated light emitting assembly. The collimated light emitting assembly and the detector detector 6 are positioned sideways. These two components can be positioned sideways at any angle. Simply adjust the angle between the beam splitter 3 and the principal optical axis of the collimated light emitting assembly so that the detection beam reflected by the beam splitter 3 enters the detector detector 6. In this embodiment, a 90-degree sideways position is employed. Furthermore, the angle between the beam splitter 3 and the principal optical axis of the light emitting assembly 1 can also be any angle, such as 45 degrees, 50 degrees, or 30 degrees. Simply adjust the position and distance of the detector detector 6 relative to the light emitting assembly 1 accordingly.

[0037] Preferably, the beam splitter 3 is made by double-sided coating, with a narrowband semi-transparent and semi-reflective film coated on the first surface of the beam splitter 3, and an AR anti-reflection film coated on the second surface of the beam splitter 3. The narrowband semi-transparent and semi-reflective film transmits part of the light beam and reflects part of the light beam according to the absorption wavelength of the target gas to be measured; the AR anti-reflection film is a transmission-enhancing film according to the absorption wavelength of the target gas to be measured, and the wavelength corresponds to the central wavelength of a typical absorption spectrum of the target gas to be measured; for example, in this embodiment, the AR anti-reflection film can enhance the transmission of a light beam of 1653.7nm, and the narrowband semi-transparent and semi-reflective film reflects 50% and transmits 50% of the light beam of 1653.7nm. Of course, there are other options for the coating method of the beam splitter 3. For example, a narrowband semi-transparent and semi-reflective film or a broadband semi-transparent and semi-reflective film can be coated on the first surface of the beam splitter 3, and the AR anti-reflection film on the second surface can be eliminated. Moreover, the splitting ratio of the beam splitter 3 can be adjusted to any ratio according to the actual working conditions. In this embodiment, a collimated light beam of 1653.7 nm is emitted from the collimated light emitting component and is incident on the narrow-band semi-transparent and semi-reflective film on the first surface of the beam splitter 3. The beam splitter 3 forms an angle of 50° with the main optical axis of the collimated light emitting component. 50% of the emitted collimated light beam is reflected and emitted onto the detection detector 6, and the remaining 50% of the light beam is transmitted through the beam splitter 3 and emitted from the measurement beam exit hole of the laser tube housing 2.

[0038] Optionally, an external optical isolator 4 is welded or glued and fixedly installed at the measurement beam exit hole to isolate the reflected light beam of the optical link from invading the interior of the wavelength self-aligning laser, further improving the accuracy of the wavelength self-aligning laser detection.

[0039] Optimally, an L-shaped heat sink 8 is fixed on the laser tube shell 2, and one side of the L-shaped heat sink 8 is fixed to the heat dissipation surface at the bottom of the light emitting component 1, so that the light emitting component 1 is cooled and dissipated by the L-shaped heat sink 8.

[0040] The preparation method of the wavelength self-aligning laser of this embodiment is as follows:

[0041] Step S1: Glue and fix the beam splitter 3 inside the laser tube shell 2, located at the intersection of the collimated light output component and the main optical axis of the detection detector 6, and the first surface splitting surface of the beam splitter 3 is coplanar with the splitting intersection, and the beam splitter 3 is at a 50° angle to the main optical axis of the collimated light output component; and at a 40° angle to the main optical axis of the detection detector 6.

[0042] Step S2: gluing and fixing the external optical isolator 4 inside the laser tube shell 2 , and positioning it in the groove of the measurement beam exit hole of the laser tube shell 2 .

[0043] Step S3: Couple the collimated light emitting assembly to the XY axis so that the collimated light beam passes through the beam splitter 3 and the external optical isolator 4 in sequence and is emitted from the center of the measurement beam exit hole of the laser tube shell 2. After the coupling is completed, the collimated light emitting assembly is welded and fixed to the laser tube shell 2.

[0044] Step S4: gluing and sealing the sealed transmission lens 5 in the laser tube shell 2, and fixing it between the light incident port of the detector 6 and the beam splitter 3.

[0045] Step S5: Fit the detector potting coupling tube body 7 onto the upper end face of the cap brim of the detector detector 6, and re-glue-seal the sealing welding point between the TO tube base and the TO tube cap of the detector detector 6, as well as the glass-metal sealing point of the TO tube base Pin of the detector detector.

[0046] Step S6: Couple the detector detector 6 with the detector potting coupling tube 7 installed to the XY axis, so that the detection beam reflected by the beam splitter 3 meets the response requirements of the detector detector 6, and then weld the detector potting coupling tube 7 to the laser tube shell 2.

[0047] Step S7: Fix the L-shaped heat sink 8 to the laser tube shell 2 with screws, and fix one side of the L-shape to the heat dissipation surface at the bottom of the collimated light emitting component with thermal conductive adhesive.

[0048] In this embodiment, a collimated light emitting component is used as a light source, thereby realizing a collimated light output self-aligning laser structure required for a fixed diffusion type gas detector.

[0049] Example 2:

[0050] This embodiment provides a wavelength self-aligning laser for gas detection, the structure of which is substantially the same as that of the wavelength self-aligning laser in the above embodiment 1, except that: Figure 2 As shown, in this embodiment, the light emitting component 1 adopts a divergent light emitting component, which is a coaxially packaged laser device with a semiconductor refrigeration module, specifically a TO-packaged DFB laser with a TEC peak wavelength of 1653.7nm, and a built-in lens. The output light beam is a conical spot with a divergence angle of 3 degrees on both the fast axis and the slow axis.

[0051] In this embodiment, the AR antireflection coating on the second surface of the beamsplitter 3 enhances the transmission of a 1653.7 nm beam. The narrowband translucent / reflective coating on the first surface of the beamsplitter 3 reflects 20% of the 1653.7 nm beam and transmits 80%. A 1653.7 nm divergent beam is emitted from the divergent light emitting assembly and incident on the narrowband translucent / reflective coating on the first surface of the beamsplitter 3. The beamsplitter 3 forms a 40° angle with the principal optical axis of the divergent light emitting assembly. Twenty percent of the emitted divergent beam is reflected and emitted to the detector 6. The remaining 80% of the beam is sequentially transmitted through the beamsplitter 3 and the external optical isolator 4, exiting through the measurement beam exit aperture of the laser housing 2.

[0052] Preferably, a built-in optical isolator 9 is provided at the light outlet of the divergent light emitting assembly. A dual optical isolator structure, comprising the built-in optical isolator 9 and the external optical isolator 4, is employed to ensure the accuracy of the self-aligning laser detection. Alternatively, the built-in optical isolator 9 of the light emitting assembly 1 can replace the external optical isolator 4 within the laser tube housing 2.

[0053] The method for preparing the wavelength self-aligning laser of this embodiment is the same as that of the above-mentioned embodiment 1.

[0054] In this embodiment, a divergent light emitting component is used as the light source, and the same structure as that used for fixing the diffusion-type gas detector in the above-mentioned embodiment 1 is adopted to realize the self-aligned laser structure for outputting the specific divergent angle cone light spot required by the remote sensing gas detector; at the same time, the layout of the dual optical isolator can further improve the stability and sensitivity of the remote sensing gas detector, and further reduce the mode hopping problem caused by reflected light.

[0055] Example 3:

[0056] This embodiment provides a wavelength self-aligning laser for gas detection, the structure of which is substantially the same as that of the wavelength self-aligning laser in the above embodiment 2, except that: Figure 3 As shown, in this embodiment, the light emitting component 1 adopts a convergent light emitting component, which is a coaxially packaged laser device with a semiconductor refrigeration module, specifically a TO-packaged DFB laser with a peak wavelength of 1653.7nm and a TEC, and a built-in lens. The output light beam is a convergent light beam that can be coupled into an optical fiber; a built-in optical isolator 9 is provided at the light outlet of the divergent light emitting component, and the external optical isolator 4 at the measuring beam exit hole is eliminated and replaced by the built-in isolator 9. At the same time, a fiber coupling member 10 for coupling and fixing an optical fiber 11 is fixedly installed at the measuring beam exit hole. The optical fiber 11 is coupled and fixed in the fiber coupling member 10, wherein the fiber coupling member 10 can be selected from but not limited to a fiber coupling pyramid sleeve.

[0057] In this embodiment, the AR antireflection coating on the second surface of beamsplitter 3 enhances the transmission of a 1653.7 nm beam. The narrowband translucent / reflective coating on the first surface of beamsplitter 3 reflects 40% of the 1653.7 nm beam and transmits 60%. A 1653.7 nm convergent beam is emitted from the converging light output assembly and incident on the narrowband translucent / reflective coating on the first surface of beamsplitter 3. Beamsplitter 3 forms a 45° angle with the principal optical axis of the diverging light output assembly. Forty percent of the emitted convergent beam is reflected and emitted to detector 6, while the remaining 60% transmits through beamsplitter 3 and is coupled into optical fiber 11.

[0058] The preparation method of the wavelength self-aligning laser of this embodiment is as follows:

[0059] Step S1: Glue and fix the beam splitter 3 inside the laser tube shell 2, located at the intersection of the converged light output component and the main optical axis of the detector detector 6, and the first surface splitting surface of the beam splitter 3 is coplanar with the splitting intersection, and the beam splitter 3 is at a 45° angle to the main optical axis of the collimated light output component; and at a 45° angle to the main optical axis of the detector detector 6.

[0060] Step S2: Couple the convergent light emitting assembly to the XY axis so that the convergent light beam passes through the beam splitter 3 and is emitted from the center of the measurement beam exit hole of the laser tube shell 2. After the coupling is completed, the convergent light emitting assembly is welded to the laser tube shell 2.

[0061] Step S3: After passing the optical fiber 11 through the inner hole of the fiber coupling pagoda sleeve, clamp it at the measurement beam exit hole of the laser tube shell 2 for XYZ coupling. When the coupling power reaches the standard, the optical fiber 11 and the fiber coupling pagoda sleeve are fixed by Y-axis welding, and the fiber coupling pagoda sleeve and the laser tube shell 2 are fixed by XY-axis welding.

[0062] Step S4: gluing and sealing the sealed transmission lens 5 in the laser tube shell 2, and fixing it between the light incident port of the detector 6 and the beam splitter 3.

[0063] Step S5: Fit the detector potting coupling tube body 7 onto the upper end face of the cap brim of the detector detector 6, and re-glue and seal the sealing welding point between the TO tube base and the TO tube cap of the detector detector 6, as well as the glass-metal sealing point of the TO tube base Pin of the detector detector 6.

[0064] Step S6: Couple the detector detector 6 with the detector potting coupling tube 7 installed to the XY axis, so that the detection beam reflected by the beam splitter 3 meets the response requirements of the detector detector 6, and then weld the detector potting coupling tube 7 to the laser tube shell 2.

[0065] Step S7: Fix the L-shaped heat sink 8 to the laser tube shell 2 with screws, and fix one side of the L-shape to the heat dissipation surface at the bottom of the convergent light emitting component with thermal conductive adhesive.

[0066] In this embodiment, a convergent light emitting component is used as the light source, and the same structure is adopted to realize the self-aligned laser with optical fiber output required by the distributed gas detector; at the same time, the built-in isolator 9 replaces the external optical isolator 4, further simplifying the product structure and improving the product's integration and manufacturability.

[0067] Example 4:

[0068] This embodiment provides a wavelength self-aligning laser for gas detection, the structure of which is substantially the same as that of the wavelength self-aligning laser in the above embodiment 1, except that: Figure 4 As shown, in this embodiment, the light emitting component 1 and the detection detector 6 are arranged opposite to each other, and the measuring beam exit hole is located on the side of the light emitting component 1. The light beam reflected by the beam splitter 3 is emitted from the measuring beam exit hole, and the light beam transmitted by the beam splitter 3 is emitted to the detection detector 6.

[0069] Specifically, a 1653.7nm collimated light beam is emitted from the collimated light emitting component and is incident on the narrow-band semi-transparent and semi-reflective film on the first surface of the beam splitter 3. The beam splitter 3 forms a 45° angle with the main optical axis of the collimated light emitting component. 50% of the emitted collimated light beam is transmitted through the beam splitter 3 and the sealed transmission lens 5 in sequence and then emitted to the detector detector 6. The remaining 50% of the measurement light beam is reflected by the beam splitter 3, penetrates the external optical isolator 4, and is emitted from the measurement beam exit hole of the laser tube shell 2.

[0070] The preparation process of the wavelength self-aligning laser of this embodiment is the same as that of the above-mentioned embodiment 1.

[0071] In this embodiment, an opposing laser tube shell is used to realize the collimated light output self-aligned laser structure required for the fixed diffusion type gas detector, in which the collimated light output component and the detection detector 6 are arranged opposite to each other.

[0072] Example 5:

[0073] This embodiment provides a wavelength self-aligning laser for gas detection, the structure of which is substantially the same as that of the wavelength self-aligning laser in the above embodiment 1, except that: Figure 5 As shown, in this embodiment, the light emitting component 1 and the detector detector 6 are placed in the same direction, and a total reflection lens 12 is provided between the beam splitter 3 and the detector detector 6 , and the total reflection lens 12 is placed opposite to the beam splitter 3 .

[0074] Specifically, the collimated light emitting assembly is arranged in the same direction as the detector detector 6, the beam splitter 3 is arranged at a 45° angle to the principal optical axis of the collimated light emitting assembly, and the total reflection lens 12 is placed opposite the beam splitter 3 and at a negative 45° angle to the detector detector 6. A 1653.7nm collimated light beam is emitted from the collimated light emitting assembly and incident on the narrow-band semi-transmissive and semi-reflective film on the first surface of the beam splitter 3. 50% of the emitted collimated light beam is reflected and emitted by the total reflection lens 12. After being fully reflected again by the total reflection lens 12 and transmitted through the sealed transmission lens 5, it is incident on the detector detector 6. The remaining 50% of the measurement light beam is transmitted through the beam splitter 3 and the external optical isolator 4 in sequence, and then emitted from the measurement beam exit hole of the laser tube housing 2.

[0075] The preparation method of the wavelength self-aligning laser of this embodiment is as follows:

[0076] Step S1: glue and fix the beam splitter 3 inside the laser tube shell 2, between the collimated light emitting component and the measurement beam emitting hole of the laser tube shell 2, and at a 45° angle to the main optical axis of the collimated light emitting component.

[0077] Step S2: The total reflection lens 12 is glued and fixed in the laser tube shell 2, located opposite to the beam splitter 3, and forming a negative 45° angle with the main optical axis of the collimated light emitting component.

[0078] Step S3: gluing and fixing the external optical isolator 4 inside the laser tube shell 2 , so as to be located in the groove of the measurement beam exit hole of the laser tube shell 2 .

[0079] Step S4: Couple the collimated light emitting assembly to the XY axis so that 50% of the collimated light beam passes through the beam splitter 3 and the external optical isolator 4 in sequence and is emitted from the center of the measurement beam exit hole of the laser tube shell 2. After the coupling is completed, the collimated light emitting assembly is welded and fixed to the laser tube shell 2.

[0080] Step S5: The sealed transmission lens 5 is glued and sealed and fixed in the laser tube shell 2, and is located between the light incident port of the detection detector 6 and the total reflection lens 12.

[0081] Step S6: Fit the detector potting coupling tube body 7 onto the upper end face of the cap brim of the detector detector 6, and re-glue-seal the sealing welding point between the TO tube base and the TO tube cap of the detector detector 6, as well as the glass-metal sealing point of the TO tube base Pin of the detector detector 6.

[0082] Step S7: Couple the detector detector 6 with the detector potting coupling tube 7 installed to the XY axis, so that the reflected detection beam meets the response requirement of the detector detector 6, and then weld the detector potting coupling tube 7 to the laser tube shell 2.

[0083] Step S8: Fix the L-shaped heat sink 8 to the laser tube shell 2 with screws, and fix one side of the L-shape to the heat dissipation surface at the bottom of the collimated light emitting component with thermal conductive adhesive.

[0084] In this embodiment, a co-directional laser tube shell and a total reflection lens 12 are used to realize the collimated light output self-aligned laser structure required by the fixed diffusion type gas detector, in which the collimated light output component and the detection detector 6 are arranged in the same direction.

[0085] In summary, the wavelength self-aligning laser provided by the present invention can use light emitting components with different beam output forms when other structural components and assembly methods remain unchanged, thereby achieving the purpose of variable output beam of the self-aligning laser, unifying the wavelength self-aligning laser structures of collimated beam output, convergent light fiber output, and specific divergent angle cone spot output under various working conditions, realizing standardized mass production, and reducing manufacturing costs.

[0086] The above examples are merely illustrative of the present invention and do not limit the scope of protection of the present invention. Any design that is identical or similar to the present invention falls within the scope of protection of the present invention.

Claims

1. A wavelength self-aligning laser for gas detection, characterized in that: It comprises a laser tube shell, and a light emitting component, a spectrometer and a detector packaged in the laser tube shell; the laser tube shell is provided with a measuring light beam exit hole, the spectrometer is located on the light emitting light path of the light emitting component, and divides the light emitting light path into a first spectrometer path and a second spectrometer path, the detector detector and the measuring light beam exit hole are respectively located on the first spectrometer path and the second spectrometer path, a sealed transmission lens is provided between the detector detector and the spectrometer, a detector potting coupling tube body is fitted on the upper end face of the tube cap brim of the detector detector, and a target gas sample to be measured is sealed in the detector detector.

2. The wavelength self-aligning laser for gas detection according to claim 1, characterized in that: The light emitting component is a collimated light emitting component, a convergent light emitting component or a divergent light emitting component.

3. The wavelength self-aligning laser for gas detection according to claim 1, characterized in that: The light emitting component and the wave detection detector are placed opposite to each other, in the same direction or sideways.

4. The wavelength self-aligning laser for gas detection as claimed in claim 3, characterized in that: When the light emitting assembly and the detector are placed in the same direction, a total reflection lens is provided between the beam splitter and the detector, and the total reflection lens is placed opposite to the beam splitter.

5. The wavelength self-aligning laser for gas detection according to claim 1, characterized in that: The beam splitter has a first surface and a second surface, the first surface is coated with a narrow-band semi-transparent and semi-reflective film, and the second surface is coated with an AR anti-reflection film.

6. The wavelength self-aligning laser for gas detection according to claim 1, characterized in that: An external optical isolator is fixedly installed at the measuring light beam exit hole.

7. The wavelength self-aligning laser for gas detection according to claim 1, characterized in that: An optical fiber coupling member for coupling and fixing an optical fiber is fixedly installed at the measuring light beam exit hole, and the second light splitting path of the light splitting plate is coupled into the optical fiber.

8. The wavelength self-aligning laser for gas detection according to claim 1, characterized in that: The light emitting end of the light emitting component is coaxially provided with a built-in optical isolator.

9. The wavelength self-aligning laser for gas detection according to claim 1, characterized in that: The light emitting component is a coaxially packaged laser device with a semiconductor refrigeration module.

10. The wavelength self-aligning laser for gas detection according to claim 9, characterized in that: It also includes an L-shaped heat sink, which is fixed on the laser tube shell, and one side of the L-shaped heat sink is fixedly attached to the heat dissipation surface at the bottom of the light emitting component.

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