Method and system for measuring temperature without secondary calibration after replacing extended lens of infrared temperature measuring device

Abstract

The present invention relates to the field of infrared temperature measurement technology, and more specifically to a method and system for measuring temperature without secondary calibration after replacing an extended lens in an infrared temperature measuring device, comprising: obtaining the relative transmittance of an original lens of the infrared temperature measuring device relative to an extended lens, and simultaneously obtaining the original measured temperature obtained by the original lens and the target measured temperature obtained by the extended lens; obtaining a spectral radiation calculation formula, and respectively calculating the spectral radiation corresponding to the target measured temperature and the lens temperature; deriving a correction formula for measuring temperature without secondary calibration after replacing the extended lens in the infrared temperature measuring device; and inversely solving the target true temperature based on the target true spectral radiation and the spectral radiation calculation formula. When the difference between the target true temperature and the original measured temperature is within a standard, it indicates that the temperature measurement calibration process of the infrared temperature measuring device after replacing the extended lens is completed. The present invention effectively avoids the need for secondary calibration of the infrared temperature measuring device on a prototype.

Description

Technical Field

[0001] The present invention relates to the field of infrared temperature measurement technology, and more particularly to a method and system for measuring temperature without secondary calibration after an infrared temperature measurement device replaces an extended lens. Background Art

[0002] Infrared temperature measurement devices often require the use of different extension lenses based on actual temperature measurement needs. However, changing extension lenses often results in a loss of temperature measurement accuracy, necessitating a tedious recalibration to restore factory-set accuracy. Unfortunately, current mainstream solutions fail to completely eliminate this necessary recalibration step, forcing manufacturers of infrared temperature measurement equipment to frequently dispatch technicians to customer sites to resolve temperature measurement errors caused by lens changes. This situation undoubtedly significantly increases companies' labor and material costs.

[0003] Similar prior art includes Chinese patent application publication number CN118089957A, which discloses a temperature compensation test method for lens replacement. The method comprises obtaining a first transmittance T1 of a reference lens and a second transmittance T2 of a lens to be compensated; calculating a transmittance compensation coefficient TV; obtaining a first grayscale value G1 of the reference lens after transmittance compensation, and a second grayscale value G2 of the lens to be compensated after transmittance compensation; obtaining a third grayscale value G3 of the lens to be compensated after lens compensation; establishing a compensated grayscale value model; obtaining a final grayscale value Gf of the lens to be compensated; obtaining a temperature value calculated from the final grayscale value Gf using a grayscale-to-temperature model; and performing temperature verification on the lens to be compensated based on the temperature value to complete the lens temperature compensation test. However, this invention does not provide high temperature measurement accuracy after lens replacement. A similar prior art is the Chinese patent application with publication number CN214251286U, which provides an infrared temperature measuring device, including a housing, a lens for collecting light reflected by a target device, a light processing module for converting an optical signal into a first electrical signal, a processor for converting the first electrical signal processed by the light processing module into a second electrical signal compatible with an external display device, and an output terminal for outputting the second electrical signal processed by the processor to an external display device. The lens is mounted on the housing, and the light processing module, the processor, and the output terminal are all placed in the housing. However, this utility model does not take into account the replacement of the lens and the temperature measurement accuracy after the lens is replaced. Therefore, the present invention proposes a method and system for temperature measurement without secondary calibration after the infrared temperature measuring device replaces the extended lens. Summary of the Invention

[0004] In order to better solve the above problems, the present invention provides a method for measuring temperature without secondary calibration after replacing the extended lens of an infrared temperature measuring device, which is achieved by performing the following steps:

[0005] Step S1: obtaining the relative transmittance of the original lens of the infrared temperature measuring device relative to the extended lens, and simultaneously obtaining the original measured temperature measured by the original lens and the target measured temperature measured by the extended lens;

[0006] Step S2: obtaining a spectral radiation calculation formula, and calculating the spectral radiation corresponding to the target measured temperature and the lens temperature respectively based on the spectral radiation calculation formula;

[0007] Step S3: deriving a correction formula for the infrared temperature measuring device to measure temperature without secondary calibration after replacing the extended lens, and using the spectral radiation amount after the correction of the extended lens temperature measurement without secondary calibration as the target true spectral radiation amount;

[0008] Step S4: Based on the target real spectral radiation and the spectral radiation calculation formula, the measured temperature of the target object measured by the original lens is inversely solved and used as the target real temperature. When the original measured temperature is within 100°C, the difference between the target real temperature and the original measured temperature is within ±2°C, or when the original measured temperature is 100°C and above, the difference between the target real temperature and the original measured temperature is within ±2%°C, indicating that the temperature measurement calibration process of the infrared temperature measuring device is completed after the extension lens is replaced.

[0009] As a preferred technical solution of the present invention, in step S2, obtaining the spectral radiation calculation formula includes:

[0010] Based on Planck's blackbody radiation formula, formula 1 is used to express the absolute blackbody radiation with a temperature of T at a fixed wavelength. The following spectral radiation:

[0011] (Formula 1)

[0012] in, represents Planck's first constant, represents Planck's second constant, T represents the temperature of the absolute black body, represents the fixed wavelength of the spectral band, The absolute black body with a temperature of T at a fixed wavelength Under the spectral radiation quantity, the absolute blackbody represents the standard source of calibration.

[0013] As a preferred technical solution of the present invention, the calculation formula for obtaining the spectral radiation amount also includes:

[0014] Based on the Planck blackbody radiation formula, Formula 2 is used to express the light wave range that the detector of the infrared temperature measuring device can receive from the absolute blackbody with a temperature of T. Spectral radiation within;

[0015] The formula 2 is expressed in the form of a definite integral:

[0016] (Formula 2)

[0017] Among them, the definite integral band It is consistent with the spectral band that can be received by the detector of the infrared temperature measuring device.

[0018] As a preferred technical solution of the present invention, in step S3, before deriving the correction formula for measuring temperature without secondary calibration after replacing the extended lens of the infrared temperature measuring device, the following is included:

[0019] According to the radiation balance theory, when electromagnetic waves are incident on any medium, absorption, reflection, and transmission will occur, and Formula 4 is satisfied. Based on Formula 4, when the infrared radiation of the target object enters the lens of the infrared temperature measurement device, radiation energy conversion occurs and is expressed by Formula 3:

[0020] (Formula 3)

[0021] in, The spectral radiation amount received by the focal plane of the detector behind the lens of the infrared temperature measuring device is represented by the target radiation, and the temperature measurement result is obtained by reverse calculation based on the formula 2. , represents the spectral radiation corresponding to the true temperature T of the absolute blackbody target, Indicates lens temperature The corresponding spectral radiation, represents the average transmittance of the lens spectrum, the spectral bands are consistent with the spectral bands that can be received by the infrared temperature measuring device, and the lens temperature represents the lens temperature of any lens, including the original lens temperature and the extended lens temperature.

[0022] As a preferred technical solution of the present invention, in step S3, before deriving the correction formula for the infrared temperature measuring device to avoid secondary calibration after replacing the extended lens, the following is also included:

[0023] According to the radiation balance theory, electromagnetic waves incident on any medium will be absorbed, reflected and transmitted, and satisfy ,in, represents the absorption rate, represents the reflectivity, Indicates transmittance.

[0024] The infrared temperature measuring device satisfies the radiation energy conversion relationship of Formula 3 before and after the expansion lens is replaced. The relationship is expressed by Formula 4:

[0025] (Formula 4)

[0026] in, It indicates the amount of radiation received by the target through the focal plane of the original lens detector of the infrared temperature measuring device. It indicates the radiation amount received by the focal plane of the detector after the target radiation passes through the infrared temperature measuring device and the extended lens is replaced. Indicates the temperature measurement result of the infrared temperature measuring device when the original lens is installed. Indicates the temperature measurement result of the infrared temperature measuring device when the extension lens is installed, Indicates the original lens temperature, represents the lens temperature of the extended lens, Indicates the average transmittance of the original lens spectrum, It represents the average transmittance of the extender lens spectrum.

[0027] As a preferred technical solution of the present invention, in step S3, a correction formula for measuring temperature without secondary calibration after the infrared temperature measuring device replaces the extended lens is derived, including:

[0028] Based on the fact that the infrared temperature measuring device satisfies the radiation energy conversion relationship of Formula 3 before and after replacing the extension lens, the correction formula for the infrared temperature measuring device to avoid secondary calibration after replacing the extension lens is derived from Formula 4 and is expressed as Formula 5:

[0029] (Formula 5)

[0030] in, It represents the average spectral transmittance of the original lens relative to the extended lens. represents the lens temperature, It indicates the temperature measurement result of the target radiation after replacing the extended lens, that is, the temperature before correction. It represents the theoretical spectral radiation amount that should be incident on the focal plane of the infrared detector after calculation by the formula 5.

[0031] As a preferred technical solution of the present invention, in step S4, the actual temperature measured by the original lens on the target object is obtained by inverse solution and used as the target real temperature:

[0032] The corrected spectral radiation is calculated based on formula 5 , the spectral radiation Substitute the spectral radiation calculation formula into the formula, and inversely solve the problem to obtain the actual temperature measured by the original lens on the target object and use it as the target real temperature.

[0033] As a preferred technical solution of the present invention, in step S1, obtaining the relative transmittance of the original lens of the infrared temperature measuring device relative to the extended lens includes:

[0034] The spectral average transmittance of the extended lens and the original lens can be obtained through the original factory spectrum test, and then the relative transmittance of the original lens relative to the extended lens can be calculated based on the spectral average transmittance.

[0035] As a preferred technical solution of the present invention, in step S2, calculating the spectral radiation corresponding to the target measured temperature and the lens temperature includes:

[0036] Substitute the target measured temperature and the lens temperature into Formula 1 or Formula 2 respectively to calculate the spectral radiation corresponding to the target measured temperature and the spectral radiation corresponding to the lens temperature.

[0037] The present invention also provides a system for measuring temperature without secondary calibration after replacing an extended lens of an infrared temperature measuring device, the system comprising:

[0038] a transmittance acquisition unit, configured to acquire the relative transmittance of the original lens of the infrared temperature measuring device relative to the extended lens, and simultaneously acquire the original measured temperature actually measured by the original lens and the target measured temperature actually measured by the extended lens;

[0039] a radiation amount calculation unit, configured to obtain a spectral radiation amount calculation formula, and calculate the spectral radiation amounts corresponding to the target measured temperature and the lens temperature respectively based on the spectral radiation amount calculation formula;

[0040] a calibration correction unit, configured to derive a correction formula for the infrared temperature measuring device to measure temperature without secondary calibration after the extension lens is replaced, and to use the spectral radiation amount after the correction of the temperature measurement without secondary calibration of the extension lens as the target true spectral radiation amount;

[0041] The radiation amount inverse calculation unit is used to inversely calculate the actual temperature measured by the original lens on the target object and use it as the target real temperature. When the original measured temperature is within 100°C, the difference between the target real temperature and the original measured temperature is within ±2°C, or when the original measured temperature is 100°C and above, the difference between the target real temperature and the original measured temperature is within ±2%°C, indicating that the temperature measurement calibration process of the infrared temperature measuring device is completed after the expansion lens is replaced.

[0042] Compared with the prior art, the beneficial effects of the present invention are at least as follows:

[0043] The technical solution of the present invention studies infrared spectral radiation theory, applies the law of conservation of energy and Kirchhoff's thermal radiation law to specific infrared temperature measurement scenarios, and uses theoretical modeling to establish a theoretical mapping model between the temperature measurement results of the original lens and the relative transmittance, lens temperature, and temperature measurement results of the extended lens. This enables the infrared extended lens to perform radiation temperature measurement on a prototype of the same model of infrared temperature measurement device. Compared to the original factory lens, the temperature measurement accuracy is within ±2°C for temperatures within 100°C and within ±2%°C for temperatures 100°C and above. On the one hand, the present invention establishes a theoretical calibration model based on radiation theory, effectively avoiding secondary calibration on the prototype and facilitating the convenient replacement of the extended lens in the infrared temperature measurement device. On the other hand, the present invention is also applicable to all infrared temperature measurement devices with extended lenses, possessing universal applicability and wide application in the field of infrared temperature measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0045] Figure 1 A flowchart of a method for measuring temperature without secondary calibration after replacing an extended lens of an infrared temperature measuring device provided by the present invention;

[0046] Figure 2 A graph showing the relationship between the temperature measurement results of the original lens and the extended lens provided by the present invention and the target temperature;

[0047] Figure 3 This is a structural diagram of the infrared temperature measurement device provided by the present invention, which can measure temperature without secondary calibration after replacing the extended lens. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0049] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but unless otherwise specified, these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, a first xx script may be referred to as a second xx script, and similarly, a second xx script may be referred to as a first xx script without departing from the scope of this application.

[0050] Infrared temperature measurement devices often require the use of different extension lenses based on actual temperature measurement needs. However, changing extension lenses often results in a loss of temperature measurement accuracy, necessitating a tedious recalibration to restore factory-set accuracy. Unfortunately, current mainstream solutions fail to completely eliminate this necessary recalibration step, forcing manufacturers of infrared temperature measurement equipment to frequently dispatch technicians to customer sites to resolve temperature measurement errors caused by lens changes. This situation undoubtedly significantly increases companies' labor and material costs.

[0051] In view of the above technical problems, the present invention proposes Figure 1 A method for measuring temperature without secondary calibration after replacing an extended lens of an infrared temperature measuring device is shown, which is implemented by performing the following steps:

[0052] Step S1: obtaining the relative transmittance of the original lens of the infrared temperature measuring device relative to the extended lens, and simultaneously obtaining the original measured temperature measured by the original lens and the target measured temperature measured by the extended lens.

[0053] Specifically, spectral testing refers to the original spectral testing. After the original spectral testing, the spectral average transmittance of the extended lens and the original lens can be obtained. Based on the spectral average transmittance, the relative transmittance of the original lens relative to the extended lens can be calculated to obtain the temperature measurement difference of the same target object under the two lenses, and the relative transmittance is used as the calibration standard for temperature measurement of the infrared temperature measuring device.

[0054] At a fixed ambient temperature, the infrared temperature measuring device was equipped with the original lens and temperature calibration was performed against blackbody targets with actual temperatures of 20°C, 50°C, 100°C, 200°C, 350°C, and 600°C. In this embodiment, the infrared temperature measuring device detector has a receivable wavelength range of 8-14 μm, and the blackbody target is a blackbody radiator. The fixed temperature environment was set in a walk-in constant temperature test room. The calibration results are shown in Table 1:

[0055] Table 1

[0056]

[0057] Based on the infrared spectrum tester, the relative transmittance of the original lens relative to the extended lens is 0.89. The spectral band tested by the infrared spectrum tester is consistent with the receivable band of the infrared temperature measurement device detector, both of which are 8~14um. The relative transmittance is the ratio of the average spectral transmittance of the original lens relative to the extended lens measured in this band.

[0058] After installing the extended lens, the infrared temperature measuring device was tested for temperature at blackbody targets with actual temperatures of 20°C, 50°C, 100°C, 200°C, 350°C, and 600°C. The test results are shown in Table 2:

[0059] Table 2

[0060]

[0061] Step S2: Obtain a spectral radiation calculation formula, and calculate the spectral radiation corresponding to the target measured temperature and the lens temperature based on the spectral radiation calculation formula.

[0062] Specifically, a functional relationship between spectral radiance, spectral band, and absolute blackbody temperature is established as the basis for calculating spectral radiance. The spectral radiance corresponding to the measured target temperature and lens temperature is calculated separately, providing a basis for calculating the spectral radiance after secondary calibration correction for extended lens temperature measurement.

[0063] Step S3: derive a correction formula for the infrared temperature measuring device to avoid secondary calibration after replacing the extended lens, and use the spectral radiation amount after the correction of the extended lens temperature measurement without secondary calibration as the target true spectral radiation amount.

[0064] Specifically, the correction formula for temperature measurement without secondary calibration after extending the lens is used to correct the difference in temperature measurement under the extended lens. Then, based on the spectral radiation corresponding to the actual measured temperature of the target and the spectral radiation corresponding to the lens temperature, the corrected spectral radiation, that is, the target true spectral radiation, can be calculated. The target true spectral radiation is closer to the actual spectral radiation of the target object being measured.

[0065] Step S4: Based on the target real spectral radiation and the spectral radiation calculation formula, the measured temperature of the target object measured by the original lens is inversely solved and used as the target real temperature. When the original measured temperature is within 100°C, the difference between the target real temperature and the original measured temperature is within ±2°C, or when the original measured temperature is 100°C and above, the difference between the target real temperature and the original measured temperature is within ±2%°C, indicating that the temperature measurement calibration process of the infrared temperature measuring device is completed after the extension lens is replaced.

[0066] Specifically, the corrected spectral radiation, that is, the target true spectral radiation and the spectral radiation calculation formula, are used to inversely solve the target true temperature. Under ideal circumstances (that is, all other influencing factors are taken into account), the target true temperature should be equal to the original measured temperature. This process verifies the effectiveness of the correction formula.

[0067] Using the measured temperature and lens temperature of the extended lens, the corresponding spectral radiation is calculated based on the spectral radiation acquisition module, and the calibrated temperature is obtained based on the extended lens temperature measurement and correction module without secondary calibration and the spectral radiation inverse temperature calculation module. The lens temperature is obtained by the temperature sensor inside the infrared temperature measurement device. In this embodiment, the lens temperature is 33.2°C after stabilization. The obtained temperature measurement results are compared with the data in Table 1 of the original lens. When the blackbody temperature is within 100°C, the difference is within ±2°C. When the blackbody temperature is 100°C or above, the difference is within ±2%°C. The accuracy is within the standard. The specific correction results are shown in Table 3:

[0068] Table 3

[0069]

[0070] Through the coordination between the above steps, the present invention effectively avoids secondary calibration on the prototype, realizes the convenience of replacing the extension lens of the infrared temperature measuring device, and is also applicable to all infrared temperature measuring devices with extension lenses. It has universality and can be widely used in the field of infrared temperature measurement.

[0071] Furthermore, in the above step S2, the calculation formula for obtaining the spectral radiation includes:

[0072] Based on Planck's blackbody radiation formula, formula 1 is used to express the absolute blackbody radiation with a temperature of T at a fixed wavelength. The following spectral radiation:

[0073] (Formula 1)

[0074] in, represents Planck's first constant, represents Planck's second constant, T represents the temperature of an absolute black body, represents a fixed wavelength of a spectral band, It means that the absolute black body with temperature T has a fixed wavelength. The spectral radiation under the absolute black body represents the standard source of calibration.

[0075] Specifically, an absolute blackbody is used to represent the target object in this invention. A blackbody is an idealized object that completely absorbs and radiates electromagnetic waves of all wavelengths at any temperature, with the radiated energy proportional to the temperature. In infrared temperature measurement, blackbodies are often used as calibration and reference standards to ensure the accuracy of infrared temperature measurement devices.

[0076] Furthermore, the calculation formula for obtaining the spectral radiation amount also includes:

[0077] Based on Planck's blackbody radiation formula, formula 2 is used to express the range of light waves that the detector of the infrared temperature measuring device can receive when the absolute blackbody with a temperature of T is used. Spectral radiation within;

[0078] Formula 2 can be expressed in the form of definite integral:

[0079] (Formula 2)

[0080] Among them, the definite integral band It is consistent with the spectral band that can be received by the detector of the infrared temperature measuring device.

[0081] Specifically, the spectral radiation corresponding to the target measured temperature and the lens temperature can be obtained by substituting the target measured temperature and the lens temperature into Formula 1 or Formula 2 respectively, which provides a basis for calculating the spectral radiation after the extended lens temperature measurement is corrected without secondary calibration.

[0082] Furthermore, in the above step S3, the correction formula for measuring the temperature without secondary calibration after the infrared temperature measuring device replaces the extended lens is derived, which includes:

[0083] According to the radiation balance theory, when electromagnetic waves are incident on any medium, absorption, reflection, and transmission will occur, and Formula 4 is satisfied. Based on Formula 4, when the infrared radiation of the target object enters the lens of the infrared temperature measurement device, radiation energy conversion occurs and is expressed by Formula 3:

[0084] (Formula 3)

[0085] in, It represents the spectral radiation received by the focal plane of the detector behind the lens of the infrared temperature measurement device. The temperature measurement result is obtained by inverse calculation based on formula 2. , Indicates the spectral radiation corresponding to the true temperature T of the absolute blackbody target, Indicates lens temperature The corresponding spectral radiation, It indicates the average transmittance of the lens spectrum. The spectral band is consistent with the spectral band that can be received by the infrared temperature measuring device. The lens temperature indicates the lens temperature of either the original lens or the extended lens.

[0086] Specifically, infrared lenses often undergo a special coating process to increase their transmittance in the effective spectral band of the infrared temperature measuring device detector, while greatly reducing their reflectivity in the effective spectral band of the infrared temperature measuring device detector. As a result, the reflection effect of the infrared lens is negligible relative to its transmission effect. According to Kirchhoff's thermal radiation theory, the emissivity of any medium is equal to its absorptivity. Therefore, when the infrared radiation of the target object enters the lens of the infrared temperature measuring device, the radiation energy conversion that occurs can be described by the above formula 3.

[0087] Furthermore, in the above step S3, before deriving the correction formula for measuring temperature without secondary calibration after the infrared temperature measuring device replaces the extended lens, the following is also included:

[0088] According to the radiation balance theory, electromagnetic waves incident on any medium will be absorbed, reflected and transmitted, and satisfy ,in, represents the absorption rate, represents the reflectivity, Indicates transmittance.

[0089] The infrared temperature measurement device satisfies the radiation energy conversion relationship of formula 3 before and after replacing the expansion lens. The relationship is expressed by formula 4:

[0090] (Formula 4)

[0091] in, It indicates the amount of radiation received by the target through the focal plane of the original lens detector of the infrared temperature measuring device. It indicates the amount of radiation received by the focal plane of the detector after the target radiation passes through the infrared temperature measuring device and the extended lens is replaced. Indicates the temperature measurement result of the infrared temperature measuring device when the original lens is installed. Indicates the temperature measurement result of the infrared temperature measuring device when the extended lens is installed. Indicates the original lens temperature. Indicates the extended lens temperature, Indicates the average transmittance of the original lens spectrum. Indicates the average transmittance of the extender lens spectrum.

[0092] Specifically, the original lens of the infrared temperature measuring device should undergo a temperature calibration process before leaving the factory, and its temperature measurement results It should be the actual target temperature. When the lens temperature is stable, the relationship between the temperature measurement results of the original lens with a spectral average transmittance of τ1 and the extended lens with a spectral average transmittance of τ2 and the target temperature is as follows: Figure 2 As shown, the slope of the curve is positively correlated with the average transmittance of the lens spectrum, and this type of curve uses the lens temperature as the flip point.

[0093] Furthermore, in step S3, a correction formula for measuring temperature without secondary calibration after replacing the extended lens of the infrared temperature measuring device is derived, including:

[0094] Based on the fact that the infrared temperature measuring device satisfies the radiation energy conversion relationship of formula 3 before and after replacing the extension lens, the correction formula for the infrared temperature measuring device to avoid secondary calibration after replacing the extension lens is derived from formula 4 and is expressed as formula 5:

[0095] (Formula 5)

[0096] in, Indicates the average spectral transmittance of the original lens relative to the extended lens. represents the lens temperature, Indicates the temperature measurement result of the target radiation after replacing the extended lens, that is, the temperature before correction. It represents the theoretical spectral radiation that should be incident on the focal plane of the infrared detector after calculation by formula 5.

[0097] Specifically, before the infrared temperature measuring device is turned on and reaches a thermal equilibrium state, the temperature of the lens is in a drifting state. The above energy conversion relationship always maintains a dynamic balance during the non-steady-state drift of the lens temperature. Since the non-steady-state drift of the lens temperature is only related to the coupling effect of the internal movement self-heating and the ambient temperature, it can be considered that the extended lens has experienced the same non-steady-state drift as the original lens, and has the same initial temperature when turned on and the same steady-state temperature after thermal equilibrium. Therefore, the above formula 4 can be used to derive a correction formula 5 for temperature measurement without secondary calibration after replacing the extended lens.

[0098] Furthermore, in the above step S4, the actual temperature measured by the original lens on the target object is obtained by inverse solution and used as the target real temperature:

[0099] The corrected spectral radiation is calculated based on formula 5 , the spectral radiation Substitute the spectral radiation calculation formula into the inverse solution to find the actual temperature of the target object measured by the original lens and use it as the true target temperature.

[0100] Furthermore, in step S1, obtaining the relative transmittance of the original lens of the infrared temperature measuring device relative to the extended lens includes:

[0101] After the original factory spectrum test, the spectral average transmittance of the extended lens and the original lens can be obtained. Based on the spectral average transmittance, the relative transmittance of the original lens to the extended lens can be calculated.

[0102] Furthermore, in step S2, calculating the spectral radiation corresponding to the target measured temperature and the lens temperature includes:

[0103] Substitute the target measured temperature and the lens temperature into Formula 1 or Formula 2 respectively to calculate the spectral radiation corresponding to the target measured temperature and the spectral radiation corresponding to the lens temperature.

[0104] The present invention also provides a system for measuring temperature without secondary calibration after replacing an extended lens of an infrared temperature measuring device, the system comprising:

[0105] a transmittance acquisition unit, configured to acquire the relative transmittance of the original lens of the infrared temperature measuring device relative to the extended lens, and simultaneously acquire the original measured temperature actually measured by the original lens and the target measured temperature actually measured by the extended lens;

[0106] a radiation amount calculation unit, configured to obtain a spectral radiation amount calculation formula, and calculate the spectral radiation amounts corresponding to the target measured temperature and the lens temperature respectively based on the spectral radiation amount calculation formula;

[0107] a calibration correction unit, configured to derive a correction formula for the infrared temperature measuring device to measure temperature without secondary calibration after the extension lens is replaced, and to use the spectral radiation amount after the correction of the temperature measurement without secondary calibration of the extension lens as the target true spectral radiation amount;

[0108] The radiation amount inverse calculation unit is used to inversely calculate the actual temperature measured by the original lens on the target object and use it as the target real temperature. When the original measured temperature is within 100°C, the difference between the target real temperature and the original measured temperature is within ±2°C, or when the original measured temperature is 100°C and above, the difference between the target real temperature and the original measured temperature is within ±2%°C, indicating that the temperature measurement calibration process of the infrared temperature measuring device is completed after the expansion lens is replaced.

[0109] In summary, the present invention studies infrared spectral radiation theory, applies the law of conservation of energy and Kirchhoff's law of thermal radiation to specific infrared temperature measurement scenarios, and uses theoretical modeling to establish a theoretical mapping model between the temperature measurement results of the original lens and the relative transmittance, lens temperature, and temperature measurement results of the extended lens. This enables the infrared extended lens to perform radiation temperature measurement on a prototype of the same model of infrared temperature measurement device. Compared to the original factory lens, the temperature measurement accuracy is within ±2°C for temperatures within 100°C and within ±2%°C for temperatures 100°C and above. On the one hand, the present invention establishes a theoretical calibration model based on radiation theory, effectively avoiding the need for secondary calibration on the prototype and facilitating the convenient replacement of extended lenses in infrared temperature measurement devices. On the other hand, the present invention is also applicable to all infrared temperature measurement devices with extended lenses, possessing universal applicability and wide application in the field of infrared temperature measurement.

[0110] It should be understood that, although the various steps in the flow chart of each embodiment of the present invention are shown in sequence according to the indication of the arrows, these steps are not necessarily performed in sequence according to the order indicated by the arrows. Unless otherwise specified herein, the execution of these steps is not strictly limited in order, and these steps can be performed in other orders. Moreover, at least a portion of the steps in each embodiment may include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily performed in sequence, but can be performed in turn or alternately with at least a portion of other steps or sub-steps or stages of other steps.

[0111] Those skilled in the art will appreciate that all or part of the processes in the above-described method embodiments can be implemented by instructing the relevant hardware through a computer program. The above-described program can be stored in a non-volatile computer-readable storage medium. When executed, the program can include the processes of the above-described method embodiments. Any reference to memory, storage, database, or other media used in the various embodiments provided herein may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct RAMbus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM).

[0112] The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0113] The above embodiments merely represent several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art may make various modifications and improvements without departing from the scope of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be based on the appended claims.

[0114] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for measuring temperature without secondary calibration after replacing an extended lens of an infrared temperature measuring device, characterized in that: The method comprises: Step S1: obtaining the relative transmittance of the original lens of the infrared temperature measuring device relative to the extended lens, and simultaneously obtaining the original measured temperature measured by the original lens and the target measured temperature measured by the extended lens; Step S2: Obtaining a spectral radiation calculation formula, and calculating the spectral radiation corresponding to the target measured temperature and the lens temperature based on the spectral radiation calculation formula, wherein the lens temperature represents the lens temperature of either the original lens or the extended lens; Step S3: deriving a correction formula for the infrared temperature measuring device to avoid secondary calibration after replacing the extended lens, which is expressed as Formula 5, and using the spectral radiation amount after the correction of the extended lens temperature measurement to avoid secondary calibration as the target true spectral radiation amount; Where T0 represents the target actual temperature, λ=τ lens1 / τ lens2 represents the spectral average transmittance and the relative transmittance of the original lens relative to the extended lens, τ lens1 Indicates the average transmittance of the original lens spectrum, τ lens2 It represents the average transmittance of the extender lens spectrum, T lens Indicates the lens temperature, T2 * represents the temperature measurement result of the target radiation after replacing the extended lens, that is, the temperature before correction, W(T0) represents the theoretical spectral radiation that should be incident on the focal plane of the infrared detector after calculation by formula 5, and W(T2 * ) represents the radiation amount received by the focal plane of the detector after the target radiation passes through the infrared temperature measuring device after the extended lens is replaced, W(T lens ) represents the lens temperature T lens The corresponding spectral radiation; Step S4: Based on the target real spectral radiation and the spectral radiation calculation formula, the measured temperature of the target object measured by the original lens is inversely solved and used as the target real temperature. When the original measured temperature is within 100°C, the difference between the target real temperature and the original measured temperature is within ±2°C, or when the original measured temperature is 100°C and above, the difference between the target real temperature and the original measured temperature is within ±2%°C, indicating that the temperature measurement calibration process of the infrared temperature measuring device is completed after the extension lens is replaced.

2. The method according to claim 1, characterized in that In step S2, the calculation formula for obtaining the spectral radiation includes: Based on Planck's blackbody radiation formula, Formula 1 is used to express the spectral radiation of an absolute blackbody with a temperature of T at a fixed wavelength λ: Wherein, C1 represents Planck's first constant, C2 represents Planck's second constant, T represents the temperature of the absolute black body, λ represents the fixed wavelength of the spectral band, M(λ, T) represents the spectral radiation of the absolute black body with a temperature of T at a certain fixed wavelength λ, and the absolute black body represents a calibration standard source.

3. The method according to claim 2, characterized in that The calculation formula for obtaining spectral radiation also includes: Based on the Planck blackbody radiation formula, the spectral radiation of the absolute blackbody with a temperature of T within the light wave range [λ1, λ2] that can be received by the detector of the infrared temperature measuring device is expressed by formula 2; The formula 2 is expressed in the form of a definite integral: The definite integral band [λ1, λ2] is consistent with the spectrum band that can be received by the detector of the infrared temperature measuring device.

4. The method according to claim 3, characterized in that In step S3, the process of deriving a correction formula for measuring temperature without secondary calibration after replacing the extended lens of the infrared temperature measuring device includes: When the infrared radiation of the target object enters the lens of the infrared temperature measuring device, radiation energy conversion occurs and is expressed as Formula 3: W(T * ) = τ lens ·W(T) + (1 - τ lens )·W(T lens ) (Equation 3) Among them, W(T * ) represents the spectral radiation amount received by the focal plane of the detector after the lens of the infrared temperature measuring device, and the temperature measurement result T is obtained by reverse calculation based on the formula 3. * , W(T) represents the spectral radiation corresponding to the true temperature T of the absolute blackbody target, τ lens represents the average transmittance of the lens spectrum, the spectral bands are consistent with the spectral bands that can be received by the infrared temperature measuring device, and the lens temperature represents the lens temperature of any lens, including the original lens temperature and the extended lens temperature.

5. The method according to claim 4, characterized in that In step S3, before deriving the correction formula for measuring temperature without secondary calibration after replacing the extended lens, the infrared temperature measuring device further includes: The infrared temperature measuring device satisfies the radiation energy conversion relationship of Formula 3 before and after the expansion lens is replaced. The relationship is expressed by Formula 4: Among them, W(T1 * ) represents the radiation amount received by the target through the focal plane of the original lens detector of the infrared temperature measuring device, T1 * Indicates the temperature measurement result of the infrared temperature measuring device when the original lens is installed, T2 * represents the temperature measurement result of the infrared temperature measuring device when the extension lens is installed, T lensl Indicates the original lens temperature, T lens2 Indicates the lens temperature of the extended lens.

6. The method according to claim 5, characterized in that In step S3, a correction formula for measuring temperature without secondary calibration after the infrared temperature measuring device replaces the extended lens is derived, including: Based on the fact that the infrared temperature measuring device satisfies the radiation energy conversion relationship of Formula 3 before and after the expansion lens is replaced, Formula 5 is derived from Formula 4.

7. The method according to claim 6, characterized in that In step S4, the actual temperature measured by the original lens on the target object is obtained by inverse solution and used as the target real temperature: The corrected spectral radiation amount W(T0) is calculated based on Formula 5, and the spectral radiation amount W(T0) is substituted into the spectral radiation amount calculation formula. The actual temperature measured by the original lens on the target object is obtained by inverse solution and used as the target true temperature.

8. The method according to claim 1, characterized in that In step S1, obtaining the relative transmittance of the original lens of the infrared temperature measuring device relative to the extended lens includes: The spectral average transmittance of the extended lens and the original lens can be obtained through the original factory spectrum test, and then the relative transmittance of the original lens relative to the extended lens can be calculated based on the spectral average transmittance.

9. The method according to claim 3, characterized in that In step S2, calculating the spectral radiation corresponding to the target measured temperature and the lens temperature includes: Substitute the target measured temperature and the lens temperature into Formula 1 or Formula 2 respectively to calculate the spectral radiation corresponding to the target measured temperature and the spectral radiation corresponding to the lens temperature.

10. A temperature measurement system for an infrared temperature measuring device that does not require secondary calibration after replacing an extended lens, characterized in that: The system comprises: a transmittance acquisition unit, configured to acquire the relative transmittance of the original lens of the infrared temperature measuring device relative to the extended lens, and simultaneously acquire the original measured temperature actually measured by the original lens and the target measured temperature actually measured by the extended lens; a radiation amount calculation unit, configured to obtain a spectral radiation amount calculation formula, and calculate the spectral radiation amounts corresponding to the target measured temperature and the lens temperature based on the spectral radiation amount calculation formula, wherein the lens temperature represents the lens temperature of either the original lens or the extended lens; a calibration correction unit, configured to derive a correction formula for the infrared temperature measuring device to eliminate the need for secondary calibration after replacing the extended lens, as expressed by Formula 5, and to use the spectral radiation amount after the correction for the temperature measurement by the extended lens without secondary calibration as the target true spectral radiation amount; Where T0 represents the target actual temperature, λ=τ lens1 / τ lens2 represents the spectral average transmittance and the relative transmittance of the original lens relative to the extended lens, τ lens1 Indicates the average transmittance of the original lens spectrum, τ lens2 It represents the average transmittance of the extender lens spectrum, T lens Indicates the lens temperature, T2 * represents the temperature measurement result of the target radiation after replacing the extended lens, that is, the temperature before correction, W(T0) represents the theoretical spectral radiation that should be incident on the focal plane of the infrared detector after calculation by formula 5, and W(T2 * ) represents the radiation amount received by the focal plane of the detector after the target radiation passes through the infrared temperature measuring device after the extended lens is replaced, W(T lens ) represents the lens temperature T lens The corresponding spectral radiation; The radiation amount inverse calculation unit is used to inversely calculate the actual temperature measured by the original lens on the target object and use it as the target real temperature. When the original measured temperature is within 100°C, the difference between the target real temperature and the original measured temperature is within ±2°C, or when the original measured temperature is at or above 100°C, the difference between the target real temperature and the original measured temperature is within ±2%°C, indicating that the temperature measurement calibration process of the infrared temperature measuring device is completed after the expansion lens is replaced.

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