Infrared thermal imager for industrial gas leakage detection

Abstract

The invention discloses an infrared thermal imager for industrial gas leakage detection, which comprises an aperture type non-uniformity correction mechanism, an infrared optical lens, a bottom plate, an imaging assembly, an imaging circuit board, a cooling fin, a fan and a temperature sensor, the aperture fixing cylinder sleeves the outer cylindrical surface of the front end of the infrared optical lens and is fixed with an annular groove in the front end of the infrared optical lens; the infrared optical lens is arranged on the upper surface of the front end of the bottom plate; the temperature sensor is mounted in a mounting groove in the front end of the bottom plate; the imaging assembly is arranged on the upper surface of the rear end of the bottom plate; the imaging circuit board is connected with the bottom plate and installed on the lower side of the rear end of the bottom plate. Infrared narrow-band gas detection is adopted, leaked gas can be displayed on a screen in a photoelectric image mode, when gas leakage occurs, an alarm signal can be sent out in time, and an accident site can be recorded.

Description

Technical Field

[0001] The invention belongs to the technical field of spectrum detection and relates to an infrared thermal imager for industrial gas leakage detection. Background Art

[0002] Currently, there are two types of gas leak detection: contact and non-contact. Contact gas detection can be divided into free diffusion detection, aspiration detection and fiber optic detection according to the type of infrared detector. Contact gas detection has high sensitivity and is relatively cheap. Each probe is designed for a certain gas to be measured, and there are many types of infrared detectors. Non-contact gas detection can be divided into laser detection and infrared detection. Laser detection is an active detection that requires a single working wavelength to be set for a specific gas to be measured. Infrared gas detection is a passive detection. In theory, as long as there is an absorption peak in the atmospheric window and a target-background temperature difference exists, it can be detected. Infrared detection can be divided into hyperspectral, multispectral and narrowband gas detection according to the degree of subdivision of the working band. Hyperspectral equipment generally uses a cooled infrared detector with an interferometer. The working bands include long wave, medium wave and full wave modes. Infrared detectors are available in unit and array modes. Compared with hyperspectral equipment using array infrared detectors, hyperspectral equipment using unit infrared detectors has higher sensitivity and a longer effective range. Hyperspectral equipment can identify the type of leaking gas. Multispectral equipment generally uses uncooled infrared detectors. Compared with hyperspectral detection equipment, it can detect fewer types of gases and has a relatively short effective range. Narrow-band gas detection generally uses array infrared detectors, which are available in cooled, uncooled, medium wave and long wave. They can image the gas being measured but cannot identify the type of gas.

[0003] At present, the above-mentioned devices have certain user groups in different application scenarios, but they have the following shortcomings:

[0004] 1) Although contact gas detection is highly sensitive and inexpensive, each probe can only detect one or several gases. Since it is contact type, even if a gas leak occurs, as long as the gas does not contact the probe, there will be no alarm. Even if a gas leak is detected, it can only send an alarm signal, and there is no traceable data.

[0005] 2) Laser detection equipment must have an active laser source and must set a single working wavelength for the gas being measured. It cannot measure gases other than cooperative gases and is more expensive.

[0006] 3) Hyperspectral and multispectral gas detection have higher sensitivity, that is, longer effective distance, compared with narrow-band gas detection. However, hyperspectral and multispectral gas detection can only detect gases that have been pre-loaded into the spectral database. In addition, hyperspectral and multispectral detection equipment has complex structure and is expensive. Summary of the invention

[0007] The purpose of the present invention is to overcome the above shortcomings and provide an infrared thermal imager for industrial gas leakage detection. It uses infrared narrow-band gas detection to display the leaked gas on the screen in the form of a photoelectric image. When a gas leak occurs, it can send out an alarm signal in time and record the accident scene. Specifically, it includes:

[0008] 1) It can image most industrial gases in real time and display them on the screen in the form of photoelectric images. When a gas leak occurs, it can send out an alarm signal in time and record the accident scene, making the accident traceable;

[0009] 2) Multiple large-area heat sinks are added outside the refrigerator and at the heat-generating components of the imaging circuit, which can conduct a large amount of heat generated by the refrigerator and the imaging circuit to the explosion-proof and non-explosion-proof housings where the thermal imager is installed; in order to ensure uniform temperature inside the housing, fans are installed at appropriate locations of the thermal imager; the product can provide 7×24 hours of uninterrupted monitoring services on site;

[0010] 3) Install a non-uniformity correction mechanism in front of the lens and multiple temperature sensors around the thermal imager to ensure that the thermal imager matches the best parameters in different temperature environments;

[0011] 4) The product has no complex motion mechanism, low production and maintenance costs, and is suitable for mass production.

[0012] The technical solution of the present invention is:

[0013] An infrared thermal imager for industrial gas leak detection adopts narrowband imaging. The infrared optical lens and infrared detector both adopt narrowband. The narrowband filter of the infrared detector is installed in the dewar to reduce the thermal noise caused by the narrowband filter. In order to improve the sensitivity of the gas leak detector, the focal plane material of the infrared detector adopts MCT (mercury cadmium telluride). The proportions of the three materials of tellurium, cadmium and mercury are configured according to the response band of the gas to be measured to ensure that the response peak of the infrared detector matches the band where the absorption peak of the gas to be measured is located. In order to achieve better correction effect under high and low temperatures, the non-uniformity correction mechanism is installed in front of the optical lens. In order to save space, the conventional fan-shaped correction plate is not used, but an aperture-type non-uniformity correction mechanism is used. The multiple blades contracted in the aperture housing are punched in and out to provide the uniform background required for the non-uniformity correction of the infrared thermal imager. In order to ensure that the system can obtain the accurate temperature of the environment around the optical system, infrared detector, and imaging circuit during the operation of the thermal imager, so as to correctly call the working parameters that match the ambient temperature, in addition to the temperature sensors provided on the infrared detector and the imaging circuit themselves, a temperature sensor is provided near the optical lens. In view of the special application scenario that the infrared thermal imager for industrial gas leak detection needs to work continuously for 7×24 hours and is installed in a closed and small explosion-proof or non-explosion-proof housing, a heat sink that is much larger than the surface of the refrigerator is installed outside the refrigerator. Part of the heat can be conducted to the bottom plate of the thermal imager through the heat sink. The bottom plate is in contact with the explosion-proof or non-explosion-proof housing, and the large amount of heat generated by the refrigerator is dissipated by heat conduction. In order to prevent local high temperature in the refrigerator, a fan is installed on the back side of the refrigerator to improve the working environment of the refrigerator; because the infrared thermal imager for industrial gas leak detection is generally installed in a small explosion-proof or non-explosion-proof housing, in order to ensure a relatively friendly working environment for the thermal imager, a fan is also provided at the front end of the lens.

[0014] The infrared thermal imager for industrial gas leakage detection is composed of an aperture-type non-uniformity correction mechanism, an infrared optical lens, a base plate, an imaging component, an imaging circuit board, a first heat sink, a second heat sink, a first fan, a second fan, etc., wherein: the aperture-type non-uniformity correction mechanism is connected to the aperture fixing tube by screws, the aperture fixing tube is sleeved on the outer cylindrical surface of the front end of the infrared optical lens, and is fixed to the annular groove at the front end of the infrared optical lens by screws; the infrared optical lens is mounted on the upper surface of the front end of the base plate and is fastened by screws; the first fan is connected to the first fan mounting bracket by screws and nuts, the first fan mounting bracket is mounted on the lower side of the base plate and is fastened by screws; the temperature sensor is mounted in the mounting groove at the front end of the base plate and is fastened by the temperature sensor pressing plate, and the temperature sensor is fixed to the front end of the base plate by screws and nuts. The degree sensor pressure plate is connected to the base plate by screws; the imaging component is installed on the upper surface of the rear end of the base plate and is fastened by screws; the imaging circuit board is connected to the base plate by the first spacer and screws, and is installed on the lower side of the rear end of the base plate; the second heat sink is installed on the lower side of the base plate and is fastened to the base plate by screws, the upper surface of the second heat sink is in contact with the base plate, and the lower surface is in contact with the first heat sink, the first heat sink is connected to the base plate by screws, and a thermal conductive pad is installed between the first heat sink and the imaging circuit board, one side of the conductive pad is in contact with the heat-generating electronic components on the imaging circuit board, and the other side is in contact with the boss on the upper surface of the first heat sink; the second fan is connected to the second fan mounting bracket by screws and nuts, and the second fan mounting bracket is connected to the base plate by screws and is installed on the rear side of the imaging component.

[0015] The imaging assembly is composed of an infrared detector assembly mounted on an infrared detector mounting plate, which is fastened by screws, and the contact surface between the infrared detector assembly and the infrared detector mounting plate is coated with thermal conductive silicone grease; the infrared detector mounting plate is mounted on the right side of the infrared detector mounting frame by screws; the main control circuit is connected to the infrared detector mounting plate by screws, and the first lens servo control circuit board and the second lens servo control circuit board are connected to the infrared detector mounting frame by a second spacer and screws, and are mounted on the left side of the infrared detector mounting frame; the first connector and the second connector are connected to the socket mounting frame by a first stud and a second stud, and the socket mounting frame is mounted on the upper surface of the infrared detector mounting frame and is mounted on the left side of the infrared detector assembly by screws; the third heat sink and the fourth heat sink are mounted on the refrigerator of the infrared detector assembly by screws, the upper surface of the inner cavity of the third heat sink and the fourth heat sink is in contact with the refrigerator, the lower end surface of the cylinder is in contact with the infrared detector mounting frame, and the contact surface between the third heat sink and the fourth heat sink and the refrigerator and the infrared detector mounting frame is coated with thermal conductive silicone grease; the network port conversion circuit mounting plate is connected to the infrared detector mounting frame by screws, and the network port conversion circuit board is mounted on the network port conversion circuit mounting plate and fastened by screws.

[0016] The aperture type non-uniformity correction mechanism is installed in front of the optical lens, and uses a plurality of blades retracted in the aperture housing, and adopts the technical means of driving in and out the blades to provide a uniform background required for the non-uniformity correction of the infrared thermal imager. When the blades are not in use, they are in a retracted state.

[0017] The infrared detector assembly adopts a cooled narrow-band focal plane infrared detector. According to the application scenario, the working band can be selected from 3.2-3.4μm, 3.0-3.5μm, 3.0-4.0μm, 4.2-4.4μm, 4.52-4.67μm, 8.0-8.6μm, 8.0-9.0μm, 8.0-9.2μm, 10.3-10.8μm, and the infrared detector specifications can be selected from 320×240 / 30μm, 320×256 / 30μm, 640 ×512 / 15μm, this embodiment adopts an integrated Stirling refrigerator, and a split Stirling refrigerator can also be selected according to the application. For medium-wave gas detection, a HOT focal plane infrared detector can also be selected; in order to improve the sensitivity of the thermal imager, the infrared detector adopts a small F#. In this embodiment, the infrared detector F# is F1.2. According to user needs, the infrared detector F# can also be selected from F1.4, F1.5, and F2.0; the infrared detector filter is installed in the dewar to reduce the additional noise caused by the filter;

[0018] The infrared optical lens, in this embodiment, uses a continuously variable magnification lens. For different application scenarios, a multi-field of view or fixed-focus optical lens can also be used. The working band of the optical lens of this embodiment is a narrow-band optical lens that matches the infrared detector. Each optical component of the optical lens is plated with an anti-reflection film that matches the working band of the infrared detector. Ordinary medium-wave or long-wave lenses can also be used, and narrow-band filters can be added to achieve narrow-band imaging.

[0019] The beneficial effects of the present invention include:

[0020] 1) Use narrow-band infrared detectors and narrow-band optical lenses, and place the infrared detector filter inside the infrared detector dewar to reduce noise and improve the signal-to-noise ratio;

[0021] 2) It can image most industrial gases, provide real-time video images, detect potential accidents in time, and ensure the traceability of accidents;

[0022] 3) The non-uniformity correction mechanism of the infrared thermal imager is installed in front of the lens, which can correct the image non-uniformity caused by the infrared lens and the infrared detector. The thermal imager can work continuously for 24 hours a day, 7 days a week in a closed and small explosion-proof or non-explosion-proof housing. The image quality of the thermal imager is always in the best state, and the life of the refrigerator is significantly improved.

[0023] 4) Several large-area heat sinks are added outside the refrigerator and at the heat-generating components of the imaging circuit, which can conduct the large amount of heat generated by the refrigerator and the imaging circuit to the explosion-proof and non-explosion-proof housings where the thermal imager is installed; in order to ensure uniform temperature inside the housing, a fan is installed at an appropriate position of the thermal imager;

[0024] 5) Multiple temperature sensors are installed in the thermal imager to ensure that the system can obtain the accurate temperature of the environment around the optical system, infrared detector, and imaging circuit during the operation of the thermal imager and when non-uniformity correction is required, so as to correctly call the working parameters that match the ambient temperature;

[0025] 6) The product has low production cost and is suitable for large-scale equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is an appearance diagram of the infrared thermal imager for industrial gas leakage detection of the present invention.

[0027] Figure 2 This is an explosion diagram of the infrared thermal imager for industrial gas leakage detection of the present invention.

[0028] Figure 3 This is an appearance diagram of the imaging component of the present invention.

[0029] In the figure:

[0030] Aperture type non-uniformity correction mechanism 1, aperture fixing tube 2, infrared optical lens 3, first screw 4, second screw 5, bottom plate 6, second screw 7, first flat washer 8, first elastic washer 9, third screw 10, second flat washer 11, second elastic washer 12, first fan mounting bracket 13, first nut 14, fourth screw 15, third flat washer 16, third elastic washer 17, first fan 18, first heat sink 19, thermal conductive pad 20, fifth screw 21, fourth flat washer 22, fourth elastic washer 23, The sixth screw 24, the fifth flat washer 25, the fifth elastic washer 26, the second heat sink 27, the seventh screw 28, the sixth flat washer 29, the sixth elastic washer 30, the imaging circuit board 31, the first spacer 32, the eighth screw 33, the seventh flat washer 34, the seventh elastic washer 35, the second fan mounting bracket 36, the second nut 37, the second fan 38, the ninth screw 39, the eighth flat washer 40, the eighth elastic washer 41, the imaging assembly 42, the tenth screw 43, the ninth flat washer 44, the ninth elastic washer 45, the tenth The first screw 46, the tenth flat washer 47, the tenth elastic washer 48, the temperature sensor pressing plate 49, the temperature sensor 50, the twelfth screw 51, the eleventh flat washer 52, the eleventh elastic washer 53, the main control circuit 54, the infrared detector mounting frame 55, the first lens servo control circuit board 56, the second spacer 57, the second lens servo control circuit board 58, the thirteenth screw 59, the twelfth flat washer 60, the twelfth elastic washer 61, the socket mounting frame 62, the fourteenth screw 63, the first connector 64, the first stud 65, a second connector 66, a second stud 67, an infrared detector mounting plate 68, a fifteenth screw 69, a thirteenth flat washer 70, a thirteenth elastic washer 71, a sixteenth screw 72, a third heat sink 73, a seventeenth screw 74, a fourteenth flat washer 75, a fourteenth elastic washer 76, an infrared detector assembly 77, a fourth heat sink 78, a network port conversion circuit mounting plate 79, an eighteenth screw 80, a network port conversion circuit board 81, a nineteenth screw 82, a fifteenth flat washer 83, and a fifteenth elastic washer 84. DETAILED DESCRIPTION

[0031] In order to make the purpose, content and advantages of the present invention more clear, the specific implementation methods of the present invention are further described in detail below in conjunction with the drawings and examples.

[0032] In one embodiment of the present invention, the infrared thermal imager for industrial gas leakage detection has a shape as follows Figure 1 As shown, the implementation method is as follows Figure 2As shown, the infrared thermal imager for industrial gas leakage detection comprises an aperture type non-uniformity correction mechanism 1 connected to an aperture fixing tube 2 by a first screw 4; the aperture fixing tube 2 is sleeved on the outer cylindrical surface of the front end of the infrared optical lens 3 and fixed to the annular groove of the front end of the infrared optical lens 3 by a second screw 5; the infrared optical lens 3 is mounted on the upper surface of the front end of the base plate 6 and fastened by a second screw 7, a first flat washer 8, and a first elastic washer 9; the first fan 18 is fixed by a fourth screw 15, a third flat washer 16, a third elastic washer 17, a first nut 14 The first fan mounting bracket 13 is connected to the first fan mounting bracket 13, which is installed on the lower side of the bottom plate 6 and is fastened to the front end surface of the bottom plate 6 by the third screw 10, the second flat washer 11, and the second elastic washer 12; the temperature sensor 50 is installed in the front end mounting groove of the bottom plate 6 and is fastened by the temperature sensor pressing plate 49, and the temperature sensor pressing plate 49 is connected to the bottom plate 6 by the eleventh screw 46, the tenth flat washer 47, and the tenth elastic washer 48; the imaging component 42 is installed on the upper surface of the rear end of the bottom plate 6 and is fastened by the tenth screw 43, the ninth flat washer 44, and the ninth elastic washer 48. The imaging circuit board 31 is connected to the bottom plate 6 by the first spacer 32, installed on the lower side of the rear end of the bottom plate 6, and fastened by the seventh screw 28, the sixth flat washer 29, and the sixth elastic washer 30; the second heat sink 27 is installed on the lower side of the bottom plate 6, and is fastened to the bottom plate 6 by the sixth screw 24, the fifth flat washer 25, and the fifth elastic washer 26. The upper surface of the second heat sink 27 contacts the bottom plate 6, and the lower surface contacts the first heat sink 19. The first heat sink 19 is fastened by the fifth screw 21, the fourth flat washer 22, and the fourth elastic washer 23 is connected to the base plate 6, the thermal conductive pad 20 is installed between the first heat sink 19 and the imaging circuit board 31, one side is in contact with the heat-generating electronic components on the imaging circuit board 31, and the other side is in contact with the boss on the upper surface of the first heat sink 19; the second fan 38 is connected to the second fan mounting bracket 36 by the ninth screw 39, the eighth flat washer 40, the eighth elastic washer 41, and the second nut 37, and the second fan mounting bracket 36 is connected to the base plate 6 by the eighth screw 33, the seventh flat washer 34, and the seventh elastic washer 35, and is installed on the rear side of the imaging component.

[0033] like Figure 3As shown, the infrared detector assembly 77 is mounted on the infrared detector mounting plate 68 and fastened with the sixteenth screw 72. The contact surface between the infrared detector assembly 77 and the infrared detector mounting plate 68 is coated with thermal conductive silicone grease; the infrared detector mounting plate 68 is connected to the infrared detector mounting frame 55 by the fifteenth screw 69, the thirteenth flat washer 70, and the thirteenth elastic washer 71, and is mounted on the right side of the infrared detector mounting frame 55; the main control circuit 54 is connected to the infrared detector mounting plate 68 by the twelfth screw 51, the eleventh flat washer 52, and the eleventh elastic washer 53, the first lens servo control circuit board 56 and the second lens servo control circuit board 58 are connected to the infrared detector mounting frame 55 by the second spacer 57, the thirteenth screw 59, the twelfth flat washer 60, and the twelfth elastic washer 61, and are mounted on the left side of the infrared detector mounting frame 55; the first connector 64 and the second connector 66 are connected to the infrared detector mounting frame 55 by the first stud 65 and the second stud 67 The socket mounting frame 62 is connected, and the socket mounting frame 62 is mounted on the upper surface of the infrared detector mounting frame 55, mounted on the left side of the infrared detector assembly 77, and fastened with the fourteenth screw 63; the third heat sink 73 and the fourth heat sink 78 are mounted on the refrigerator of the infrared detector assembly 77, and are fastened with the seventeenth screw 74, the fourteenth flat washer 75, and the fourteenth elastic washer 76. The upper surface of the inner cavity of the third heat sink 73 and the fourth heat sink 78 contacts the refrigerator, and the lower end surface of the cylinder contacts the infrared detector mounting frame 55. Thermal conductive silicone grease is applied on the contact surface of the third heat sink 73 and the fourth heat sink 78 with the refrigerator and the contact surface with the infrared detector mounting frame 55; the network port conversion circuit mounting plate 79 is connected to the infrared detector mounting frame 55 with the eighteenth screw 80, and the network port conversion circuit board 81 is mounted on the network port conversion circuit mounting plate 79, and is fastened with the nineteenth screw 82, the fifteenth flat washer 83, and the fifteenth elastic washer 84.

Claims

1. An infrared thermal imager for industrial gas leak detection, characterized in that: The invention comprises an aperture type non-uniformity correction mechanism, an infrared optical lens, a bottom plate, an imaging component, an imaging circuit board, a first heat sink, a second heat sink, a first fan, a second fan, and a temperature sensor, wherein: the aperture type non-uniformity correction mechanism is connected to an aperture fixing tube, the aperture fixing tube is sleeved on the outer cylindrical surface of the front end of the infrared optical lens and fixed to the annular groove at the front end of the infrared optical lens; the infrared optical lens is mounted on the upper surface of the front end of the bottom plate; the first fan is connected to the first fan mounting bracket, and the first fan mounting bracket is mounted on the lower side of the bottom plate; the temperature sensor is mounted in the mounting groove at the front end of the bottom plate, and is fastened by a temperature sensor pressing plate, and the temperature sensor is pressed against the bottom plate. The sensor pressure plate is connected to the base plate; the imaging assembly is mounted on the upper surface of the rear end of the base plate; the imaging circuit board is connected to the base plate and mounted on the lower side of the rear end of the base plate; the second heat sink is mounted on the lower side of the base plate, the upper surface of the second heat sink contacts the base plate, and the lower surface contacts the first heat sink, the first heat sink is connected to the base plate by screws, a thermally conductive pad is installed between the first heat sink and the imaging circuit board, one side of the conductive pad contacts the heat-generating electronic components on the imaging circuit board, and the other side contacts the boss on the upper surface of the first heat sink; the second fan is connected to the second fan mounting bracket, the second fan mounting bracket is connected to the base plate and mounted on the rear side of the imaging assembly.

2. The infrared thermal imager for industrial gas leakage detection according to claim 1, characterized in that: The imaging assembly is composed of an infrared detector assembly mounted on an infrared detector mounting plate, and the contact surface between the infrared detector assembly and the infrared detector mounting plate is coated with thermal conductive silicone grease; the infrared detector mounting plate is mounted on the right side of the infrared detector mounting frame; the main control circuit is connected to the infrared detector mounting plate, and the first lens servo control circuit board and the second lens servo control circuit board are connected to the infrared detector mounting frame by using a second spacer and screws, and are mounted on the left side of the infrared detector mounting frame; the first connector and the second connector are connected to the socket mounting frame by using a first stud and a second stud, and the socket mounting frame is mounted on the upper surface of the infrared detector mounting frame and is mounted on the left side of the infrared detector assembly; The third heat sink and the fourth heat sink are installed on the refrigerator of the infrared detector assembly, the upper surfaces of the third heat sink and the fourth heat dissipation cavity are in contact with the refrigerator, the lower end surface of the cylinder is in contact with the infrared detector mounting frame, and the contact surfaces of the third heat sink and the fourth heat sink with the refrigerator and the infrared detector mounting frame are coated with thermal conductive silicone grease; the network port conversion circuit mounting board is connected to the infrared detector mounting frame, and the network port conversion circuit board is installed on the network port conversion circuit mounting board.

3. The infrared thermal imager for industrial gas leakage detection according to claim 1, characterized in that: The aperture type non-uniformity correction mechanism is installed in front of the optical lens, and uses multiple blades retracted in the aperture housing to provide a uniform background required for the non-uniformity correction of the infrared thermal imager by driving the blades in and out. When the blades are not in use, they are in a retracted state.

4. The infrared thermal imager for industrial gas leakage detection according to claim 1, characterized in that: The infrared detector focal plane material is made of mercury cadmium telluride, and the proportions of the three materials, tellurium, cadmium and mercury, are configured according to the response band of the measured gas to ensure that the infrared detector response peak matches the band where the measured gas absorption peak is located.

5. The infrared thermal imager for industrial gas leakage detection according to any one of claims 1 to 4, characterized in that: The infrared detector assembly adopts a cooled narrow-band focal plane infrared detector, and its working band is selected from 3.2-3.4μm, 3.0-3.5μm, 3.0-4.0μm, 4.2-4.4μm, 4.52-4.67μm, 8.0-8.6μm, 8.0-9.0μm, 8.0-9.2μm or 10.3-10.8μm.

6. The infrared thermal imager for industrial gas leakage detection according to claim 5, characterized in that: The infrared detector specification is selected as 320×240 / 30μm, 320×256 / 30μm or 640×512 / 15μm.

7. The infrared thermal imager for industrial gas leakage detection according to claim 5, characterized in that: The refrigerated narrow-band focal plane infrared detector adopts an integrated or split Stirling refrigerator, or a HOT focal plane infrared detector is selected when used for medium-wave gas detection.

8. The infrared thermal imager for industrial gas leakage detection according to any one of claims 1 to 4, characterized in that: The F# of the infrared detector is F1.2, F1.4, F1.5 or F2.

0.

9. The infrared thermal imager for industrial gas leakage detection according to any one of claims 1 to 4, characterized in that: The infrared detector comprises a filter, which is installed in the Dewar and is used to reduce the additional noise caused by the filter.

10. The infrared thermal imager for industrial gas leakage detection according to any one of claims 1 to 4, characterized in that: The infrared optical lens adopts a continuously variable magnification, multi-field of view or fixed-focus optical lens.

Images