Multi-spectral temperature measurement device and temperature measurement method thereof

Abstract

A multi-spectral temperature measurement device and method thereof include: obtaining first and second wavelength light information of a measured target; obtaining the ratio of the output voltage of the measured target at two wavelength bands and the ratio of the dual-band radiant brightness based on the first and second wavelength light information; and obtaining the temperature of the measured target based on the functional relationship between the output voltage ratio and the dual-band radiant brightness ratio, and the relationship between the spectral blackbody radiation emittance and the absolute temperature of the wavelength. The multi-spectral temperature measurement device and method thereof can achieve panoramic non-contact temperature measurement in high-risk scenarios.

Description

Technical Field

[0001] The present invention relates to the field of fire detection and alarm technology in the field of deep learning, and in particular to a multi-spectral temperature measurement device and a temperature measurement method thereof. Background Art

[0002] Panoramic monitoring of unexpected high-temperature risks in high-risk areas of coal chemical plants plays a vital role in fire detection and early warning. The most important aspect of temperature measurement is the accuracy of experimental data. Non-contact spectral temperature measurement, with its advantages of fast response, wide monitoring range, accuracy, and convenience, has widely replaced traditional contact thermocouple temperature measurement methods and has become a key tool for accident prevention and economic efficiency improvement. Existing non-contact temperature measurement methods include infrared thermal imagers, colorimetric temperature measurement, and luminance temperature measurement. Infrared thermal imagers are subject to factors such as high-temperature measurement, emissivity, atmospheric transmittance, and light interference that can affect accurate temperature measurement. Colorimetric temperature measurement is only suitable for high-temperature locations and can mitigate the effects of environmental interference and object emissivity to a certain extent. Luminance temperature measurement utilizes the principle that the brightness of a substance's monochromatic radiation changes with temperature, offering strong resistance to environmental interference. While absorption from optical path media and changes in the surface emissivity of the object being measured have less impact on the reading than with conventional radiation thermometers, it does suffer from the problem of receiving less radiation energy. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a multi-spectral temperature measurement device and a temperature measurement method thereof, so as to realize panoramic non-contact temperature measurement in high-risk scenarios.

[0004] In order to solve the above technical problems, the present invention provides a multi-spectral temperature measurement device, comprising:

[0005] a first wavelength lens assembly, for acquiring first wavelength optical information of a measured target and introducing the first wavelength optical information into an optical processing assembly;

[0006] a second wavelength lens assembly, configured to obtain second wavelength optical information of the measured target and introduce the second wavelength optical information into the optical processing assembly;

[0007] The optical processing component is used to perform spectroscopic processing on the received first wavelength light information and second wavelength light information respectively, and converge the monochromatic light after the spectroscopic processing to the detector module;

[0008] The detector module is used to detect the optical signal, convert the received optical signal and then input it to the processing module;

[0009] The processing module is used to process the received data according to a specified temperature measurement algorithm to obtain the temperature of the measured target.

[0010] Further, the first wavelength lens assembly includes: a first filter and a first wavelength lens;

[0011] The second wavelength lens assembly includes a second filter and a second wavelength lens.

[0012] Furthermore, the spectral range of the first wavelength lens is 7.5-14µm.

[0013] The spectral range of the second wavelength lens is 1.5-5.1µm.

[0014] Furthermore, the optical processing component includes: a narrow light hole, an aperture, a first reflector, a grating and a second reflector, wherein:

[0015] The light focused by the first wavelength lens or the second wavelength lens is introduced through an infrared optical fiber, passes through the narrow light hole and the aperture, and is reflected by the first reflector to the grating. The grating separates the parallel polychromatic light into monochromatic light according to wavelength, and then converges to the detector module through the second reflector.

[0016] Furthermore, the processing module is used to process the received data according to a specified temperature measurement algorithm to obtain the temperature of the target under measurement, including: obtaining the ratio of the output voltages of the target under measurement at two bands and the ratio of the dual-band radiation brightness according to the first wavelength light information and the second wavelength light information; obtaining the temperature of the target under measurement according to the functional relationship between the output voltage ratio and the dual-band radiation brightness ratio, and the relationship between the spectral blackbody radiation emittance and the absolute temperature of the wavelength.

[0017] The present invention also provides a multi-spectral temperature measurement method, which is implemented using the multi-spectral temperature measurement device described above, and includes:

[0018] respectively acquiring first wavelength light information and second wavelength light information of the measured target;

[0019] Obtaining a ratio of output voltages of the target under test at two wavelength bands and a ratio of dual-band radiation brightness according to the first wavelength light information and the second wavelength light information;

[0020] The temperature of the measured target is obtained according to the functional relationship between the ratio of the output voltages and the ratio of the dual-band radiation brightness, and the relationship between the spectral blackbody radiation emittance and the absolute temperature of the wavelength.

[0021] Wherein, the output voltage ratio The functional relationship between the ratio of the dual-band radiation brightness K is:

[0022]

[0023] in, f(λ) is the spectral transmittance of the filter; D (λ) is the spectral response function of the photoelectric converter; F (λ) is the spectral transmittance of the optical system; ε (λ, T ) is the emissivity of the object at a certain temperature and wavelength; where:

[0024]

[0025]

[0026]

[0027]

[0028] The dual-band method assumes that the surface characteristics of the object being measured are similar to a gray body, and the object radiates two bands per unit surface area in all directions of its upper hemisphere space per unit time. 、 The radiation energy is and , the emissivity is 、 , the ratio of the two is K, and the ratio relationship is listed as follows:

[0029]

[0030] make , derive the expanded form of the numerator and denominator on the right side of the equation

[0031]

[0032] Therefore

[0033]

[0034] According to the measured emissivity and experimental results, cubic spline interpolation fitting is performed to predict the temperature of target objects in coal chemical sites.

[0035] The relationship between the spectral blackbody radiation emittance and the absolute temperature of the wavelength is:

[0036]

[0037] in, c 1 = 2 πhc 2 = 3.74 × 10 -16 , c 2 = hc / k = 1.43879×10 -2 , cis the speed of light, k and h are the Boltzmann constant and Planck's constant respectively.

[0038] The multispectral temperature measurement device and method of this invention combine colorimetric and luminance temperature measurement. They are used in coal chemical industrial parks to monitor the temperature of various devices in a scene, thereby achieving panoramic non-contact temperature measurement. This method is suitable for measuring the actual temperature and spectral emissivity of high-temperature materials, composite materials, and ablative materials. The technology of this invention has demonstrated excellent development prospects in practical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 Schematic diagram of a multi-spectral temperature measurement device according to an embodiment of the present invention;

[0040] Figure 2 is a schematic diagram of a multi-spectral temperature measurement device according to another embodiment of the present invention;

[0041] Figure 3 The figure is a flow chart of a multi-spectral temperature measurement method of the present invention. DETAILED DESCRIPTION

[0042] To make the purpose, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, unless there is a conflict, the embodiments and features in the embodiments of the present application can be combined with each other in any manner.

[0043] In order to better understand the present invention, the present invention is further described below with reference to the accompanying drawings and specific embodiments.

[0044] An embodiment of the present invention provides a multi-spectral temperature measurement device, which is used for panoramic monitoring of unexpected high-temperature risks in high-risk scenes in coal chemical parks, including panoramic temperature monitoring of typical flammable and explosive places such as coal transportation corridors, public pipeline corridors, coal chemical gasification equipment, oil tank areas, and hazardous materials parking lots. It can also provide a basis for the early study of the characteristics and laws of hidden dangers and disasters.

[0045] Figure 1 FIG. 1 is a schematic diagram of a multi-spectral temperature measurement device according to an embodiment of the present invention. Figure 1 As shown, the multi-spectral temperature measurement device 10 of this embodiment includes:

[0046] The first wavelength lens component 11 is used to obtain first wavelength light information of the measured target and introduce the first wavelength light information into the optical processing component 13;

[0047] The second wavelength lens component 12 is used to obtain the second wavelength light information of the measured target and introduce the second wavelength light information into the optical processing component 13;

[0048] The optical processing component 13 is used to perform spectroscopic processing on the received first wavelength light information and second wavelength light information, and converge the monochromatic light after the spectroscopic processing to the detector module 14;

[0049] The detector module 14 is used to detect the optical signal, convert the received optical signal and input it to the processing module 15;

[0050] The processing module 15 is configured to process the received data according to a specified temperature measurement algorithm to obtain the temperature of the measured object.

[0051] In another embodiment, the processing module 15 is used to process the received data according to a specified temperature measurement algorithm to obtain the temperature of the target under measurement, including: obtaining the ratio of the output voltages of the target under measurement at two bands and the ratio of the dual-band radiation brightness according to the first wavelength light information and the second wavelength light information; obtaining the temperature of the target under measurement according to the functional relationship between the output voltage ratio and the dual-band radiation brightness ratio, and the relationship between the spectral blackbody radiation emittance and the absolute temperature of the wavelength.

[0052] The spectral range of the first wavelength lens is 7.5-14µm.

[0053] The spectral range of the second wavelength lens is 1.5-5.1µm.

[0054] The multi-spectral temperature measurement device of this embodiment utilizes multiple spectral channels within a single instrument, utilizing the object's radiant brightness measurement information from multiple spectra and then processing the data to determine the object's temperature and the material's spectral emissivity. This method requires no auxiliary equipment or additional information, and has no special requirements for the measured object. It is particularly suitable for simultaneously measuring the true temperature and material emissivity of high and extremely high temperature targets.

[0055] like Figure 2 As shown, the multi-spectral temperature measurement device of this embodiment includes: a filter 101, a medium-wave infrared lens 102, a long-wave infrared lens 103, an infrared optical fiber 104, a light hole 105, an aperture 106, a reflector 107, a grating 108, a reflector 109, a detector module 109, a USB 110, and a host 111. It is connected to the host via a USB to perform a photoelectric conversion array and signal processing to complete signal acquisition and data storage processing.

[0056] The thermal radiation emitted by the target object serves as the light source. After passing through filter 101, this radiation removes some broad-spectrum stray light. Subsequent radiation is then converged by medium-wave infrared lens 102 and long-wave infrared lens 103 before being introduced through infrared fiber 104 and into the optical processing assembly. The light first passes through a collimation system consisting of a narrow aperture 105, an aperture 106, and a reflector 107. The narrow aperture 105 determines the total light energy entering the system. The reflector 107 converts the light passing through aperture 105 into parallel light. Next, a grating 108 performs a spectroscopic operation, separating the parallel, multi-color light into monochromatic light by wavelength. A reflector 109 converges this dispersed monochromatic light onto the focal plane of the detector, ensuring that each specific wavelength is accurately received by the detector. Upon receiving the optical signal, the detector converts it into an electrical signal, which then undergoes a series of circuit processing steps, including amplification and A / D conversion, before being converted into digital information that can be read by the host computer. This digital information is transmitted to the host computer 111 via the USB 110 interface and then processed by designated software. The designated software uses a multi-spectral radiometric temperature measurement algorithm to perform sophisticated processing on the collected data. This algorithm can determine important parameters such as the actual temperature and emissivity of the measured object.

[0057] The multi-spectral temperature measuring device of the embodiment of the present invention can monitor large-scale coal chemical parks. Since the medium-wave and long-wave spectral ranges and temperatures can cover the coal transportation corridors, public pipeline corridors, coal chemical gasification equipment, oil tank areas, hazardous materials parking lots and other places in the coal chemical park, the temperature measuring device of this embodiment can be deployed at a distance of 50m from the target to be measured to obtain a larger field of view to achieve panoramic monitoring.

[0058] After analyzing experimental data, a combined medium- and long-wave infrared monitoring method was adopted. Based on extensive experimental data, the temperature of typical locations in coal chemical parks ranges from 20.5°C to 110°C. Given the temperature range of long-wave infrared lenses (-20°C to 1000°C) and medium-wave infrared lenses (+5°C to 150°C), it can be concluded that these typical locations in coal chemical parks can be covered by medium- and long-wave infrared cameras. The images collected during the experiments show that in typical coal chemical scenes such as coal transportation corridors, public pipeline corridors, coal chemical gasification plants, oil tank farms, and hazardous materials parking lots, at the same resolution (e.g., 640px × 480px), medium-wave infrared cameras capture richer details and a wider image tolerance (natural transitions between light and dark) than long-wave infrared cameras. Therefore, medium- and long-wave infrared cameras can capture the different radiated light patterns of the target object. The following calculation method can accurately determine the temperature of the target object.

[0059] The multi-spectral temperature measurement method of this embodiment is described in detail below. Figure 3As shown, the multi-spectral temperature measurement method of this embodiment is implemented based on the above-mentioned multi-spectral temperature measurement device, and includes the following steps:

[0060] Step S100, respectively obtaining first wavelength light information and second wavelength light information of the measured target;

[0061] Step S200: Obtain the ratio of the output voltage of the target under test at two wavelengths and the ratio of the dual-band radiation brightness according to the first wavelength light information and the second wavelength light information. ;

[0062] Step S300 , obtaining the temperature of the measured target according to the functional relationship between the ratio of the output voltages and the ratio of the dual-band radiation brightness, and the relationship between the spectral blackbody radiation emittance and the absolute temperature of the wavelength.

[0063] In this embodiment, the functional relationship between the ratio of the output voltage of the target object under test at the two bands and the ratio of the dual-band radiation brightness is:

[0064]

[0065] in, is the spectral transmittance of the filter; is the spectral response function of the photoelectric converter; is the spectral transmittance of the optical system; is the emissivity of the measured object at a certain temperature and wavelength; where:

[0066]

[0067] It can be simplified to:

[0068] The dual-band method assumes that the surface characteristics of the object being measured are similar to a gray body, and the object radiates two bands per unit surface area in all directions of its upper hemisphere space per unit time. 、 The radiation energy is and , the emissivity is 、 , the ratio of the two is K, and the ratio relationship is listed as follows:

[0069]

[0070] In the derivation process, Planck's law describes the spectral distribution of radiation energy. Its corresponding formula shows that the relationship between the spectral blackbody radiation emittance and the absolute temperature of the wavelength is:

[0071] ,

[0072] in,c 1 = 2 πhc 2 = 3.74 × 10 -16 , c 2 = hc / k = 1.43879×10 -2 , c is the speed of light, k and h are the Boltzmann constant and Planck's constant respectively.

[0073] Similarly, according to Wien's formula,

[0074]

[0075] make , derive the expanded form of the numerator and denominator on the right side of the equation

[0076]

[0077] Therefore

[0078]

[0079] According to the measured emissivity and experimental results, cubic spline interpolation fitting is performed to predict the temperature of target objects in coal chemical sites.

[0080] A filter is added in front of the infrared lens to filter out broad-spectrum sunlight. Taking into account interference from refraction and reflection, it removes excess light, allowing only light waves around 940nm to enter the infrared receiver. This filter was selected for its characteristics: uniform spectral distribution, a transmittance range of 1µm-15µm, and high resistance to damage from strong light.

[0081] This experiment used a long-wave infrared lens and a medium-wave infrared lens to sample the same scene at the same time and location. The main parameters are as follows:

[0082]

[0083] In this embodiment, cubic spline interpolation fitting is performed based on the measured emissivity and experimental results to predict the temperature of the target object in the coal chemical site.

[0084] The temperatures of typical coal chemical scenes, such as coal transportation corridors, public pipeline corridors, coal chemical gasification units, oil tank farms, and hazardous materials parking lots, were collected. The test images are as follows:

[0085] Panoramic monitoring was carried out in the closed coal transportation corridor, and the temperature range of the measured objects was 21.6℃-74.4℃.

[0086] Panoramic monitoring of the public pipeline corridor is carried out, and the temperature range of the measured objects is 30.4℃-81.5℃.

[0087] Panoramic monitoring of the petrochemical tank area of ​​the coal chemical gasification unit is carried out, and the temperature range of the measured objects is 26.2℃-101.0℃.

[0088] The oil tank farm scene is monitored panoramically, and the temperature range of the measured objects is 20.5℃-86.4℃.

[0089] Panoramic monitoring of hazardous materials parking lots is carried out, and the temperature range of the measured objects is 25.0℃-37.9℃.

[0090] Through non-contact temperature measurement, we can achieve panoramic temperature monitoring of unexpected high-temperature risks in high-risk areas of large-scale coal chemical scenes. By combining medium and long waves and using the idea of ​​differentiation to solve the errors of multi-spectral temperature measurement, we can achieve effective monitoring of the scene, focus on solving the technical difficulties faced in preventing and resolving major risks in the industry, and propose scientific and effective early warning and detection methods to achieve source-based, pre-emptive and precise prevention and control of such major fires.

[0091] Those skilled in the art will appreciate that all or part of the steps in the above method can be performed by a program instructing the relevant hardware, and the program can be stored in a computer-readable storage medium, such as a read-only memory, a magnetic disk, or an optical disk. Alternatively, all or part of the steps in the above embodiment can also be implemented using one or more integrated circuits. Accordingly, each module / unit in the above embodiment can be implemented in the form of hardware or in the form of software functional modules. The present invention is not limited to any particular combination of hardware and software.

[0092] The above are only preferred embodiments of the present invention. Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A multi-spectral temperature measurement device, characterized in that: include: a first wavelength lens assembly, for acquiring first wavelength optical information of a measured target and introducing the first wavelength optical information into an optical processing assembly; a second wavelength lens assembly, configured to obtain second wavelength optical information of the measured target and introduce the second wavelength optical information into the optical processing assembly; The optical processing component is used to perform spectroscopic processing on the received first wavelength light information and second wavelength light information respectively, and converge the monochromatic light after the spectroscopic processing to the detector module; The detector module is used to detect the optical signal, convert the received optical signal and then input it to the processing module; The processing module is configured to process the received data according to a specified temperature measurement algorithm to obtain the temperature of the target under test, including: obtaining a ratio of the output voltages of the target under test at two wavelengths and a ratio of the dual-band radiant brightness according to the first wavelength light information and the second wavelength light information; obtaining the temperature of the target under test according to a functional relationship between the output voltage ratio and the dual-band radiant brightness ratio, and a relationship between the spectral blackbody radiation emittance and the absolute temperature of the wavelength. The output voltage ratio The functional relationship between the ratio of the dual-band radiation brightness K is: , in, is the spectral transmittance of the filter; is the spectral response function of the photoelectric converter; is the spectral transmittance of the optical system; is the emissivity of the measured object at a certain temperature and wavelength; where: ， but , The dual-band method assumes that the surface characteristics of the object being measured are similar to a gray body, and the object radiates two bands per unit surface area in all directions of its upper hemisphere space per unit time. 、 The radiation energy is and , the emissivity is 、 The ratio of the two is , the following ratio relationships are listed: , make , derive the expanded form of the numerator and denominator on the right side of the equation Therefore ， According to the measured emissivity and experimental results, cubic spline interpolation fitting is performed to obtain the temperature of the measured target.

2. The multi-spectral temperature measurement device according to claim 1, characterized in that: The relationship between the spectral blackbody radiation emittance and the absolute temperature of the wavelength is: , in, c 1 = 2 πhc 2 = 3.74 × 10 -16 , c 2 = hc / k = 1.43879×10 -2 , c is the speed of light, k and h are the Boltzmann constant and Planck's constant respectively.

3. The multi-spectral temperature measurement device according to claim 1, characterized in that: The first wavelength lens assembly includes: a first filter and a first wavelength lens; The second wavelength lens assembly includes a second filter and a second wavelength lens.

4. The multi-spectral temperature measurement device according to claim 3, characterized in that: The spectral range of the first wavelength lens is 7.5-14µm; The spectral range of the second wavelength lens is 1.5-5.1µm.

5. The multi-spectral temperature measurement device according to claim 4, characterized in that: The optical processing component includes: a narrow light hole, an aperture, a first reflector, a grating and a second reflector, wherein, The light focused by the first wavelength lens or the second wavelength lens is introduced through an infrared optical fiber, passes through the narrow light hole and the aperture, and is reflected by the first reflector to the grating. The grating separates the parallel polychromatic light into monochromatic light according to wavelength, and then converges to the detector module through the second reflector.

6. A multi-spectral temperature measurement method, implemented using the multi-spectral temperature measurement device according to any one of claims 1 to 5, characterized in that: include: respectively acquiring first wavelength light information and second wavelength light information of the measured target; Obtaining a ratio of output voltages of the target under test at two wavelength bands and a ratio of dual-band radiation brightness according to the first wavelength light information and the second wavelength light information; The temperature of the target is obtained according to the functional relationship between the ratio of the output voltages and the ratio of the dual-band radiation brightness, and the relationship between the spectral blackbody radiation emittance and the absolute temperature of the wavelength. The output voltage ratio The functional relationship between the ratio of the dual-band radiation brightness K is: , in, is the spectral transmittance of the filter; is the spectral response function of the photoelectric converter; is the spectral transmittance of the optical system; is the emissivity of the measured object at a certain temperature and wavelength; where: , but , The dual-band method assumes that the surface characteristics of the object being measured are similar to a gray body, and the object radiates two bands per unit surface area in all directions of its upper hemisphere space per unit time. 、 The radiation energy is and , the emissivity is 、 , the ratio of the two is K, and the ratio relationship is listed as follows: ， make , derive the expanded form of the numerator and denominator on the right side of the equation Therefore , According to the measured emissivity and experimental results, cubic spline interpolation fitting is performed to obtain the temperature of the measured target.

7. The multi-spectral temperature measurement method according to claim 6, characterized in that: The relationship between the spectral blackbody radiation emittance and the absolute temperature of the wavelength is: , in, c 1 = 2 πhc 2 = 3.74 × 10 -16 , c 2 = hc / k = 1.43879×10 -2 , c is the speed of light, k and h are the Boltzmann constant and Planck's constant respectively.

8. The multi-spectral temperature measurement method according to claim 6 or 7, characterized in that: The spectral range of the first wavelength lens is 7.5-14µm. The spectral range of the second wavelength lens is 1.5-5.1µm.

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