1. An imaging sensor structure for VOC gas emission comprises an infrared lens, an infrared light splitting element, a long-wave pass infrared filter, a first infrared focal plane detector, a second infrared focal plane detector, an infrared image processing module and a display module; the infrared lens receives scene infrared radiation and outputs the scene infrared radiation to the infrared light splitting element; the infrared light splitting element outputs a first path of infrared radiation and a second path of infrared radiation, the first path of infrared radiation is output to a first infrared focal plane detector through a long-wave-pass infrared filter, and the second path of infrared radiation is output to a second infrared focal plane detector; the output ends of the first infrared focal plane detector and the second infrared focal plane detector are connected to the infrared image processing module; the output end of the infrared image processing module is connected with the display module; the cut-off edge of the long-wave pass infrared filter is 3.3-3.7 mu m; the method is characterized in that: the infrared image processing module or the display module is connected with an alarm device, and an openable shading element is arranged between the condenser lens and the infrared light splitting element.

2. The imaging sensor structure for VOC gas emission according to claim 1, wherein: and a light guide element is arranged between the condenser lens and the infrared light splitting element.

3. The imaging sensor structure for VOC gas emission according to claim 2, wherein: the light guide element includes an optical fiber.

4. The imaging sensor structure for VOC gas emission according to claim 2, wherein: the light guide element is a mirror.

5. The imaging sensor structure for VOC gas emission according to claim 3 or 4, wherein: the shading element is positioned in front of or behind the light guide element and comprises a shading plate which is used for shading the light guide element or opening the light guide element.

6. The imaging sensor structure for VOC gas emission according to claim 5, wherein: the condenser lens comprises a concave mirror, and the starting point of the light guide element is positioned at the focus of the concave mirror.

7. The imaging sensor structure for VOC gas emission according to claim 6, wherein: the aperture of the concave mirror is larger than that of the infrared lens.

Background

The method is used as the prop industry of national economy in the petrochemical industry, provides necessary petroleum energy and chemical products for social development, and also belongs to key industrial pollution sources. The air pollution is mainly in an unorganized emission form, and the pollutants are mainly various high-concentration volatile organic gases (VOC), so that great harm is brought to the ecological environment and human health. How to rapidly monitor the existence of VOC gas leakage, effectively evaluate the distribution state and diffusion trend of the leaked gas in the space, and accurately position the gas leakage source, so that relevant departments and personnel can rapidly take effective measures to prevent the occurrence of major gas leakage accidents is a problem which needs to be solved urgently.

The infrared imaging monitoring technology for gas leakage has the remarkable advantages of high efficiency, long distance, large range, dynamic and intuitive performance, and becomes a research hotspot in all countries in the world, and gradually becomes an important means for monitoring gas leakage. Gas leakage infrared imaging detection techniques can be largely classified into two major categories, active imaging based on absorption of laser source radiation and passive imaging based on absorption of background radiation. The gas leakage laser active infrared imaging detection technology has the advantages that due to the existence of radiation sources such as laser and the like, the system is generally large in volume and weight, relatively low in safety, limited by a laser light source, limited in detectable spectral range, few in detectable gas types, and rapidly weakened in signal along with the distance, most of the currently applied systems need a scanning mechanism, and the systems are relatively complex. The VOC gas leakage passive infrared imaging monitoring technology has the advantages of remarkable remote detection capability, large detectable spectral range, multiple detectable gas types, no background reflection and radiation source required by a system, relatively simple structure, adoption of an array detector, direct imaging and positioning, relative temperature difference between the detected gas and the background, poor signal-to-noise ratio, need of special optical structure optimization, image enhancement and other processing technologies. Common typical passive imaging monitoring technologies for VOC gas leakage mainly include a simple infrared thermal imaging monitoring technology, a multispectral imaging monitoring technology and a hyperspectral imaging monitoring technology. The simple infrared imaging VOC monitoring technology is realized by adding a narrow-band filter matched with the VOC gas infrared spectrum in an optical system of a single infrared camera, and the technical means reduces the signal-to-noise ratio of the monitoring system, thereby reducing the sensitivity of the VOC gas imaging monitoring system. The multispectral imaging technology and the hyperspectral imaging technology can obtain the fine spectrum of the VOC gas, but the multispectral imaging technology and the hyperspectral imaging technology are expensive, long in scanning time, poor in real-time performance and large in size.

Chinese patent application No. 2020100297460 discloses a spectral infrared imaging monitoring device for VOC gas leakage, including: the infrared imaging system comprises an infrared lens, an infrared light splitting element, a long-wave-pass infrared filter, a first infrared focal plane detector, a second infrared focal plane detector, an infrared image processing module and a display module; the infrared lens receives scene infrared radiation and outputs the scene infrared radiation to the infrared light splitting element; the infrared light splitting element outputs a first path of infrared radiation and a second path of infrared radiation, the first path of infrared radiation is output to a first infrared focal plane detector through a long-wave-pass infrared filter, and the second path of infrared radiation is output to a second infrared focal plane detector; the output ends of the first infrared focal plane detector and the second infrared focal plane detector are connected to the infrared image processing module; the cut-off edge of the long-wave pass infrared filter is 3.3-3.7 μm.

However, in the case of few VOC gases or limited infrared light, the set of infrared imaging detection devices generally cannot sensitively acquire the state of the VOC gases.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides the device which can effectively detect a small amount of VOC gas and improve the detection sensitivity.

In order to achieve the purpose, the invention provides the following technical scheme: an imaging sensor structure for VOC gas emission comprises an infrared lens, an infrared light splitting element, a long-wave pass infrared filter, a first infrared focal plane detector, a second infrared focal plane detector, an infrared image processing module and a display module; the infrared lens receives scene infrared radiation and outputs the scene infrared radiation to the infrared light splitting element; the infrared light splitting element outputs a first path of infrared radiation and a second path of infrared radiation, the first path of infrared radiation is output to a first infrared focal plane detector through a long-wave-pass infrared filter, and the second path of infrared radiation is output to a second infrared focal plane detector; the output ends of the first infrared focal plane detector and the second infrared focal plane detector are connected to the infrared image processing module; the output end of the infrared image processing module is connected with the display module; the cut-off edge of the long-wave pass infrared filter is 3.3-3.7 mu m; the infrared image processing module or the display module is connected with an alarm device, and an openable shading element is arranged between the condenser lens and the infrared light splitting element.

Further, a light guide element is arranged between the condenser lens and the infrared light splitting element.

Further said light guiding element comprises an optical fiber.

Further the light guiding element is a mirror.

The shading element is further positioned in front of or behind the light guide element and comprises a shading plate which is used for shading the light guide element or opening the light guide element.

The condensing lens further comprises a concave mirror, and the starting point of the light guide element is positioned at the focus of the concave mirror.

Further, the aperture of the concave mirror is larger than that of the infrared lens.

Compared with the prior art, the invention has the beneficial effects that: can assemble the infrared radiation of scene department through condensing lens, the reinforcing reaches the infrared radiation intensity of infrared light splitting component department, improves holistic sensitivity, detects when being little concentration VOC.

Drawings

Fig. 1 is a schematic structural view of an imaging sensor for VOC gas emission according to the present invention.

Reference numerals: 1. an infrared lens; 2. an infrared spectroscopic element; 3. a long-wave pass infrared filter; 4. a first infrared focal plane detector; 5. a second infrared focal plane detector; 6. an infrared image processing module; 7. a display module; 8. an alarm device; 9. a condenser lens; 10. a light guide element.

Detailed Description

In the description of the present invention, it should be noted that, for the terms of orientation, such as "central", "lateral (X)", "longitudinal (Y)", "vertical (Z)", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicate that the orientation and positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and should not be construed as limiting the specific scope of the present invention.

Furthermore, if the terms "first" and "second" are used for descriptive purposes only, they are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features. Thus, a definition of "a first" or "a second" feature may explicitly or implicitly include one or more of the features, and in the description of the invention, "a number" or "a number" means two or more unless explicitly specified otherwise.

An imaging sensor structure for VOC gas emission comprises an infrared lens 1, an infrared light splitting element 2, a long-wave pass infrared filter 3, a first infrared focal plane detector 4, a second infrared focal plane detector 5, an infrared image processing module 6 and a display module 7; the infrared lens 1 receives scene infrared radiation and outputs the scene infrared radiation to the infrared light splitting element 2; the infrared light splitting element 2 outputs a first path of infrared radiation and a second path of infrared radiation, the first path of infrared radiation is output to a first infrared focal plane detector 4 through a long-wave pass infrared filter 3, and the second path of infrared radiation is output to a second infrared focal plane detector 5; the output ends of the first infrared focal plane detector 4 and the second infrared focal plane detector 5 are connected to an infrared image processing module 6; the output end of the infrared image processing module 6 is connected with the display module 7; the cut-off edge of the long-wave pass infrared filter 3 is 3.3-3.7 mu m; the infrared scene imaging system further comprises a condenser lens 9, the condenser lens 9 converges and enhances the infrared radiation of the scene to be output to the infrared light splitting element 2, the infrared image processing module 6 or the display module 7 is connected with an alarm device 8, and an openable shading element (not shown) is arranged between the condenser lens 9 and the infrared light splitting element 2.

The preferred orientation of the condenser lens 9 is the same as that of the infrared lens 1.

In this embodiment, a light guide element 10 is preferably disposed between the condenser lens 9 and the infrared spectroscopic element 2.

The light guide element 10 of the present embodiment preferably includes an optical fiber.

Or the light guiding element 10 of the present embodiment is preferably a mirror.

The shading element is preferably located in front of or behind the light guide element 10, and the shading element includes a shading plate for shading the light guide element 10 or opening the light guide element 10.

The condenser lens 9 of the present embodiment preferably includes a concave mirror, and the starting point of the light guide element 10 is located at the focal point of the concave mirror.

The aperture of the preferred concave mirror is larger than the infrared lens.

Normally receive scene infrared radiation and export to infrared spectroscopic component 2 through infrared camera lens 1 to finally by the accurate demonstration of display, low in VOC concentration, infrared camera lens 1 receives infrared radiant quantity and crosses when low unable formation image, condensing lens 9 will assemble the infrared radiation in the scene, the reinforcing reaches infrared spectroscopic component 2 department infrared radiant intensity, make infrared image processing module 6 can handle and show on display module 7, also can sensitive detect when guaranteeing the low concentration.

The invention connects the alarm device 9 at the image processing module or the display module 7, when VOC is detected, an alarm is generated, then the light guide element 10 is shielded by the light shielding plate, the light path (dotted line light path in figure 1) from the condenser lens 9 to the infrared light splitting element 2 is disconnected, the light path (solid line light path in figure 1) from the infrared lens 1 to the infrared light splitting element 2 is kept smooth, and when the concentration is enough, the infrared image processing module 6 can obtain accurate VOC gas images.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may occur to those skilled in the art without departing from the principle of the invention, and are considered to be within the scope of the invention.