A method for calibrating an infrared thermal imager and an infrared thermal imager

Abstract

The application discloses a correction method of an infrared thermal imager and the thermal imager. The method comprises the following steps: acquiring an initial gray value of a target object collected by the infrared thermal imager, wherein the difference between the collection time of the initial gray value and the start-up time of the infrared thermal imager is not more than a preset time threshold; acquiring a temperature value of the infrared thermal imager measured; determining a gray value adjustment value corresponding to the temperature value according to a preset calculation rule; generating a target gray value according to the gray value adjustment value and the initial gray value; and determining the temperature of the target object according to a preset conversion rule of temperature and gray value and the target gray value, so that the influence of the temperature change of the infrared thermal imager on the measured temperature is avoided, the accurate temperature can be measured after starting up, and the use efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of infrared thermal imaging technology, and in particular to a calibration method for an infrared thermal imager and an infrared thermal imager. Background Technology

[0002] Any object with a temperature above absolute zero (-273.15℃) constantly emits infrared radiation (thermal radiation). Infrared radiation is a type of electromagnetic wave with a wavelength range of 0.7μm to 1000μm, and the wavelength of radiation emitted by an object varies depending on its temperature. Infrared thermal imagers can capture infrared radiation, convert it into electrical signals, and then process the signals using algorithms to output the final temperature information.

[0003] Infrared thermal imagers, with their advantages of being non-contact, highly accurate, fast, and convenient, are widely used in fields such as petrochemicals, medical identification, and power safety. However, because the detectors in infrared thermal imagers are temperature-sensitive components, the power consumption of the electronic devices causes the overall structural temperature of the imager to rise for a period of time after the imager is turned on. This rise in overall structural temperature causes changes in the infrared radiation energy received by the detector, ultimately resulting in variations and inaccuracies in the measured temperature. Without temperature calibration, the temperature of the infrared thermal imager will not stabilize for 30 minutes after startup, and only after the temperature stabilizes will the measured temperature of the target be accurate and reliable. This waiting time causes great inconvenience to users. Therefore, how to make the imager accurate in temperature measurement immediately after startup is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the main objective of this invention is to provide a calibration method for an infrared thermal imager, the method comprising:

[0005] The initial grayscale value of the target object acquired by the infrared thermal imager is obtained, and the difference between the acquisition time of the initial grayscale value and the power-on time of the infrared thermal imager does not exceed a preset time threshold.

[0006] Obtain the measured temperature value from the infrared thermal imager;

[0007] According to the preset calculation rules, the grayscale value adjustment value corresponding to the temperature value is determined;

[0008] A target grayscale value is generated based on the grayscale adjustment value and the initial grayscale value;

[0009] The temperature of the target object is determined according to the preset conversion rules between temperature and grayscale value and the target grayscale value.

[0010] In some embodiments, acquiring the initial grayscale value of the target object captured by the infrared thermal imager includes:

[0011] The initial grayscale value of the target object is determined based on the infrared radiation collected by the detector of the infrared thermal imager.

[0012] The temperature value obtained from the infrared thermal imager includes:

[0013] The temperature value of a preset component is obtained by measurement, and the detector is installed on the preset component.

[0014] In some embodiments, determining the temperature of the target object based on a preset temperature-grayscale value conversion rule and the target grayscale value includes:

[0015] An initial temperature is generated based on the preset conversion rules between temperature and grayscale values ​​and the target grayscale value.

[0016] The temperature of the target object is determined based on the preset temperature compensation parameter corresponding to the distance between the infrared thermal imager and the target object, and the initial temperature.

[0017] In some embodiments, determining the temperature of the target object based on a preset temperature compensation parameter corresponding to the distance between the infrared thermal imager and the target object and the initial temperature includes:

[0018] The temperature of the target object is determined based on the ambient humidity of the infrared thermal imager, the corresponding preset temperature compensation parameters, and the initial temperature.

[0019] In some embodiments, the preset time threshold is 30 minutes.

[0020] Secondly, this application provides a calibration device for an infrared thermal imager, the device comprising:

[0021] The acquisition module is used to acquire the initial grayscale value of the target object collected by the infrared thermal imager, wherein the difference between the acquisition time of the initial grayscale value and the power-on time of the infrared thermal imager does not exceed a preset time threshold; and to acquire the measured temperature value of the infrared thermal imager.

[0022] The calculation module is used to determine the grayscale value change coefficient corresponding to the temperature value according to preset calculation rules; determine the corresponding grayscale value adjustment value according to the grayscale value change coefficient and the temperature value; and generate a target grayscale value according to the grayscale value adjustment value and the initial grayscale value.

[0023] The judgment module is used to determine the temperature of the target object based on the preset conversion rules between temperature and grayscale value and the target grayscale value.

[0024] Thirdly, this application provides an infrared thermal imager, comprising:

[0025] A detector used to collect infrared radiation from a target object;

[0026] A preset component, wherein the detector is disposed on the preset component;

[0027] A temperature sensor is used to collect the temperature value of the preset component;

[0028] The processing device is used to determine the initial grayscale value of the target object based on the infrared radiation of the target object collected by the detector of the infrared thermal imager, wherein the difference between the infrared radiation collection time and the power-on time of the infrared thermal imager does not exceed a preset time threshold.

[0029] Obtain the temperature value of the preset component collected by the temperature sensor;

[0030] According to the preset calculation rules, the gray value change coefficient corresponding to the temperature value is determined;

[0031] Based on the grayscale value change coefficient and the temperature value, determine the corresponding grayscale value adjustment value;

[0032] A target grayscale value is generated based on the grayscale adjustment value and the initial grayscale value;

[0033] The temperature of the target object is determined according to the preset conversion rules between temperature and grayscale value and the target grayscale value.

[0034] In some embodiments, the preset component includes a flange, and the detector is disposed on the outer surface of the flange or embedded in the flange.

[0035] In some embodiments, the infrared thermal imager further includes a lens for focusing infrared radiation emitted by the target object onto the detector.

[0036] In some embodiments, the processing device can also be used to generate an initial temperature based on a preset conversion rule between temperature and grayscale value and the target grayscale value; and to determine the temperature of the target object based on a preset temperature compensation parameter corresponding to the distance between the infrared thermal imager and the target object and the initial temperature.

[0037] The beneficial effects achieved by this invention are as follows:

[0038] This application provides a calibration method and a thermal imager for an infrared thermal imager. The method acquires the initial grayscale value of a target object collected by the infrared thermal imager, wherein the difference between the acquisition time of the initial grayscale value and the power-on time of the infrared thermal imager does not exceed a preset time threshold; acquires the measured temperature value of the infrared thermal imager; determines the grayscale adjustment value corresponding to the temperature value according to a preset calculation rule; generates a target grayscale value based on the grayscale adjustment value and the initial grayscale value; and determines the temperature of the target object according to a preset conversion rule between temperature and grayscale value and the target grayscale value. This application, by measuring the temperature of the infrared thermal imager, calculates and determines the corresponding grayscale adjustment value based on the temperature value, and determines the true grayscale value of the target object based on the grayscale adjustment value and the initial grayscale value of the target object, thereby determining the temperature of the target object. This avoids the influence of the infrared thermal imager's temperature changes on the measured temperature of the target object, and allows the infrared thermal imager to measure accurate temperatures immediately upon power-on, improving the efficiency of the infrared thermal imager. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of the structure of the infrared thermal imager provided in the embodiments of this application;

[0041] Figure 2 This is a schematic diagram of the flange structure provided in an embodiment of this application;

[0042] Figure 3 This is a schematic diagram of an infrared thermal imager with the lens removed, provided in an embodiment of this application;

[0043] Figure 4 This is a schematic diagram of infrared thermal imager temperature measurement provided in an embodiment of this application;

[0044] Figure 5 This is a schematic diagram of the infrared thermal imager structure provided in the embodiments of this application;

[0045] Figure 6 This is a flowchart of the method provided in the embodiments of this application;

[0046] Figure 7 A chart comparing the temperature measurement performance of an infrared thermal imager calibrated using the calibration method provided in this application with that of a prior art infrared thermal imager is shown. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0048] As described in the background section, when a thermal imager is first turned on, its own temperature changes, leading to inaccurate temperature measurements. To address this issue, this application proposes a calibration method for infrared thermal imagers. This method avoids the influence of temperature changes in the infrared thermal imager on the measured temperature of the target object, allowing the infrared thermal imager to measure accurate temperatures immediately upon startup, thus improving the efficiency of the infrared thermal imager.

[0049] Example 1

[0050] like Figure 1 As shown in the embodiment of this application, the infrared thermal imager includes an optical lens 1, a temperature sensor 2, an infrared detector 3, an information processing module 4, and a flange 5. The optical lens 1 is used to focus the infrared radiation emitted by the target object whose temperature is to be measured onto the infrared detector 3. The infrared detector 3 is used to generate a corresponding analog signal based on the infrared radiation and send it to the information processing module 4. The information processing module 4 generates a corresponding grayscale value based on the received analog signal and outputs the corresponding temperature data based on the grayscale value. The flange 5 is a commonly used structural component of infrared thermal imagers, mainly used to fix the optical lens. The infrared detector can be set on the outer surface of the flange or embedded in the flange.

[0051] Figure 2 A cross-sectional structure of a flange is shown. Due to the close proximity of the flange to the infrared detector, the infrared radiation emitted by the flange will significantly affect the grayscale value and temperature reading of the target object measured by the infrared detector. To facilitate quantification of the influence of the infrared thermal imager's temperature on the measured grayscale value, the temperature of the flange can be considered as the temperature of the infrared thermal imager. Alternatively, the temperature of any other component of the infrared detector or the average temperature of all components of the infrared detector can be used as the temperature of the infrared detector; this application does not limit this approach. Figure 1 As shown, temperature sensor 2 can be installed on flange 5 to measure the temperature of flange 5. Specifically, infrared detector can also be installed on any other component, and temperature sensor can also be installed on that component to measure the component's temperature.

[0052] The grayscale value change coefficient corresponding to each temperature value can be determined in advance through experiments. The experimental process may include:

[0053] A1, such as Figure 3As shown, the lens of the infrared thermal imager is removed and the detector 3 is made to face the standard blackbody radiation source 6 directly, so that the standard blackbody radiation source fills the entire field of view of the infrared thermal imager, and the temperature of the standard blackbody radiation source is adjusted to the preset temperature.

[0054] A blackbody is an object that can completely absorb incident radiation of any wavelength at any temperature. A blackbody has zero reflectivity and zero transmittance, and an absorptivity of 1. A standard blackbody radiation source is a radiation source manufactured according to the blackbody standard and is the absolute standard for developing infrared equipment.

[0055] The infrared thermal imager can be left to stand for a sufficient period of time, such as a day, to allow its temperature to stabilize.

[0056] A2. Turn on the infrared thermal imager. Detector 3 collects infrared radiation once every preset time period. The processing device generates the first gray value C_object_initial_aver of the standard blackbody radiation source based on the infrared radiation collected by detector 3. At the same time, it obtains the temperature value T_flange of the flange collected by the temperature sensor at the same time.

[0057] The system can stop collecting infrared radiation, flange temperature, and generating grayscale values ​​when the number of generated grayscale values ​​meets preset conditions.

[0058] Since the detector receives infrared radiation from both the standard blackbody radiation source and the flange, the output grayscale value C_object_initial is affected by the infrared radiation from the flange and cannot be used to accurately measure the temperature of the blackbody.

[0059] The first grayscale values ​​C_object_initia_aver_1, C_object_initia_aver_2...C_object_initia_aver_m and the corresponding flange temperature values ​​T_flange_1, T_flange_2...T_flange_m collected at the same time were measured.

[0060] A3. After the core temperature of the thermal imager stabilizes, detector 3 collects infrared radiation every preset time interval. The processing device generates a second grayscale value C_object_initia_aver of a standard blackbody radiation source based on the infrared radiation collected by detector 3. When the number of generated second grayscale values ​​meets a preset condition, the average grayscale value C_object_initia_aver_stab of the second grayscale value C_object_initia_aver is calculated. Preferably, the temperature of the flange can be obtained by a temperature sensor about 30 minutes after the infrared thermal imager is turned on. When the change in flange temperature within 5 minutes is less than 0.1 degrees Celsius, it can be determined that the core temperature of the thermal imager is stable. At this time, the temperature of the infrared thermal imager has stabilized, so the value of the second grayscale value C_object_initia_aver collected at this time is no longer affected by the flange temperature and tends to be stable.

[0061] A4. Based on the first gray value and the average gray value, determine the gray value variation coefficient corresponding to each temperature value;

[0062] Based on the first grayscale value, the grayscale value variation coefficient K corresponding to each temperature value can be calculated, i.e., K_t1 = (C_object_initia_aver_stab - C_object_initia_aver_1) / Delta_T_flange, K_t2 = (C_object_initia_aver_stab - C_object_initia_aver_2) / Delta_T_flange, K_t3 = (C_object_initia_aver_stab - C_object_initia_aver_3) / Delta_T_flange, ... K_tm = (C_object_initia_aver_stab - C_object_initia_aver_m) / Delta_T_flange. Here, Delta_T_flange represents a preset time value, such as 1 second. The grayscale value variation coefficient K represents how the grayscale value changes over time under the corresponding temperature value T_flange. Based on K_t1, K_t2…K_tm, a functional relationship between the K value and the temperature value T_flange can be established as K=f(T_flange(t)). For example, the functional relationship can be expressed as K=q*T_flange+r, where q and r represent real-valued parameters obtained by fitting the experimentally obtained K value and temperature value.

[0063] On the other hand, experiments can be conducted in advance to determine the conversion rules between temperature and grayscale values. The experimental process includes:

[0064] B1, such as Figure 4 As shown, the infrared thermal imager, after its temperature has stabilized, is positioned facing the standard blackbody radiation source 6, so that the standard blackbody radiation source 6 fills the entire field of view of the infrared thermal imager.

[0065] B2. Adjust the temperature T_blackbody of the standard blackbody radiation source and record the average gray value C_out of the infrared thermal imager's processing device based on the infrared radiation collected by the detector at the temperature of each standard blackbody radiation source.

[0066] B3. Based on T_blackbody and the corresponding C_out, establish the functional relationship between grayscale value and temperature value: C_out = g(T_blackbody), and its inverse function is T_blackbody = g -1 (C_out). For example, the functional relationship can be C_out=a*T_blackbody^2+b*T_blackbody+c; T_blackbody=-b+sqrt(b^2-4*a*c+4*a*Cout), where a, b, and c are constant values ​​determined based on experimentally obtained T_blackbody and the corresponding C_out.

[0067] Specifically, the process of correcting the temperature measurement results of an infrared thermal imager, based on the established conversion rules between temperature and grayscale values ​​and the grayscale value variation coefficient corresponding to the temperature value, includes:

[0068] Step 1: Obtain the initial grayscale value of the target object captured by the detector of the infrared thermal imager;

[0069] The difference between the initial grayscale value acquisition time and the power-on time of the infrared thermal imager shall not exceed a preset time threshold. Preferably, the preset time threshold may be 30 minutes.

[0070] Step 2: Obtain the temperature value of the flange collected by the temperature sensor;

[0071] The difference between the acquisition time of the temperature value and the acquisition time of the initial grayscale value does not exceed the corresponding threshold. For example, the first temperature value can be acquired simultaneously with the initial grayscale value, or it can be acquired shortly before or after the acquisition of the initial grayscale value. The short time can be any time range, such as no more than 1 second.

[0072] Step 3: Determine the grayscale value variation coefficient corresponding to the temperature value based on the functional relationship between the grayscale value variation coefficient K and the temperature value.

[0073] Step 4: Determine the corresponding grayscale value adjustment value based on the grayscale value change coefficient and the preset time value;

[0074] The grayscale value adjustment value can be obtained from Delta_T_flange*K, where Delta_T_flange is the preset time value, such as 1s, and K can be obtained from the function K=f(T_flange(t)) and the flange temperature value T_flange(t).

[0075] Step 5: Generate the target grayscale value based on the grayscale adjustment value and the initial grayscale value;

[0076] The target grayscale value can be represented by C_object_initial+Delta_T_flange*K, where C_object_initial represents the initial grayscale value and Delta_T_flange*K represents the grayscale value adjustment value.

[0077] Step 6: Determine the temperature of the target object based on the target grayscale value and the preset conversion rules between temperature and grayscale value;

[0078] Preferably, the initial temperature of the target object can be determined based on the target grayscale value and a preset conversion rule between temperature and grayscale value. Then, based on the ambient humidity of the infrared thermal imager and the target object's environment, a corresponding humidity adjustment coefficient is determined; based on the distance between the infrared thermal imager and the target object, a corresponding distance-temperature compensation parameter is determined; and based on the humidity adjustment coefficient, the distance-temperature compensation parameter, and the initial temperature, the temperature of the target object is determined to further improve the accuracy of the temperature measurement results.

[0079] Figure 7 A chart comparing the temperature measurement performance of an infrared thermal imager calibrated using the correction method provided in this application with that of a prior art infrared thermal imager is shown. The dashed line represents the temperature measurement result of the infrared thermal imager using the correction method provided in this application on a standard blackbody radiation source at 35°C, while the solid line represents the temperature measurement result of a conventional infrared thermal imager without the correction method provided in this application on the same 35°C standard blackbody radiation source. The test environment was an indoor temperature of 25°C and a humidity of 36.9%. During the test, the infrared thermal imager was mounted on a bracket and positioned 4m away from the blackbody. The imaging center temperature measurement point of the infrared thermal imager was aligned with the center point of the blackbody. The distance compensation parameter of the infrared thermal imager was set to 4m. The infrared thermal imager was pre-powered off and allowed to stand for more than 12 hours to allow it to fully thermally equalize with the environment before being powered on and data acquisition began. Figure 7It can be seen that the infrared thermal imager that did not use the calibration method provided in this solution only had an error of less than the preset error range requirement when the temperature measurement result was less than the actual value of 35℃ after 24 minutes of startup and temperature measurement. However, the infrared thermal imager that used the calibration method provided in this application had an error of less than the preset error range requirement when the temperature measurement result was less than the actual value of 35℃ after 1 minute of startup, thus achieving the effect of accurate temperature measurement immediately after startup.

[0080] Example 2

[0081] Corresponding to the above embodiments, such as Figure 6 As shown, this application provides a calibration method for an infrared thermal imager, the method comprising:

[0082] 610. Obtain the initial grayscale value of the target object acquired by the infrared thermal imager, wherein the difference between the acquisition time of the initial grayscale value and the power-on time of the infrared thermal imager does not exceed a preset time threshold.

[0083] 620. Obtain the measured temperature value from the infrared thermal imager;

[0084] Preferably, acquiring the initial grayscale value of the target object captured by the infrared thermal imager includes:

[0085] 621. Determine the initial grayscale value of the target object based on the infrared radiation collected by the detector of the infrared thermal imager.

[0086] The temperature value obtained from the infrared thermal imager includes:

[0087] 622. Obtain the measured temperature value of the preset component, with the detector placed on the preset component.

[0088] 630. Determine the grayscale adjustment value corresponding to the temperature value according to the preset calculation rules;

[0089] 640. Generate a target grayscale value based on the grayscale adjustment value and the initial grayscale value;

[0090] 650. Determine the temperature of the target object according to the preset conversion rules between temperature and grayscale value and the target grayscale value.

[0091] Preferably, determining the temperature of the target object based on a preset conversion rule between temperature and grayscale value and the target grayscale value includes:

[0092] 651. Generate an initial temperature according to the preset conversion rules between temperature and grayscale value and the target grayscale value;

[0093] 652. Determine the temperature of the target object based on the preset temperature compensation parameter corresponding to the distance between the infrared thermal imager and the target object and the initial temperature.

[0094] Preferably, determining the temperature of the target object based on a preset temperature compensation parameter corresponding to the distance between the infrared thermal imager and the target object, and the initial temperature, includes:

[0095] 653. Determine the temperature of the target object based on the ambient humidity of the infrared thermal imager, the corresponding preset temperature compensation parameters, and the initial temperature.

[0096] Preferably, the preset time threshold is 30 minutes.

[0097] Example 3

[0098] Corresponding to the above embodiments, this application provides a calibration device for an infrared thermal imager, the device comprising:

[0099] The acquisition module is used to acquire the initial grayscale value of the target object collected by the infrared thermal imager, wherein the difference between the acquisition time of the initial grayscale value and the power-on time of the infrared thermal imager does not exceed a preset time threshold; and to acquire the measured temperature value of the infrared thermal imager.

[0100] The calculation module is used to determine the grayscale value change coefficient corresponding to the temperature value according to preset calculation rules; determine the corresponding grayscale value adjustment value according to the grayscale value change coefficient and the temperature value; and generate a target grayscale value according to the grayscale value adjustment value and the initial grayscale value.

[0101] The judgment module is used to determine the temperature of the target object based on the preset conversion rules between temperature and grayscale value and the target grayscale value.

[0102] Preferably, the acquisition module can also be used to determine the initial grayscale value of the target object based on the infrared radiation of the target object collected by the detector of the infrared thermal imager; and to acquire the measured temperature value of a preset component, wherein the detector is located on the preset component.

[0103] Preferably, the judgment module can also be used to generate an initial temperature based on a preset conversion rule between temperature and grayscale value and the target grayscale value; and to determine the temperature of the target object based on a preset temperature compensation parameter corresponding to the distance between the infrared thermal imager and the target object and the initial temperature.

[0104] Preferably, the judgment module can also be used to determine the temperature of the target object based on the ambient humidity of the infrared thermal imager, the corresponding preset temperature compensation parameter, and the initial temperature.

[0105] Example 4

[0106] Corresponding to the above embodiments, such as Figure 5 As shown, this application provides an infrared thermal imager, including a detector 510 for collecting infrared radiation from a target object; a preset component 520 on which the detector is disposed; a temperature sensor 530 for collecting the temperature value of the preset component; and a processing device 540 for determining the initial grayscale value of the target object based on the infrared radiation collected by the detector of the infrared thermal imager, wherein the difference between the infrared radiation collection time and the power-on time of the infrared thermal imager does not exceed a preset time threshold.

[0107] Obtain the temperature value of the preset component collected by the temperature sensor;

[0108] According to the preset calculation rules, the gray value change coefficient corresponding to the temperature value is determined;

[0109] Based on the grayscale value change coefficient and the temperature value, determine the corresponding grayscale value adjustment value;

[0110] A target grayscale value is generated based on the grayscale adjustment value and the initial grayscale value;

[0111] The temperature of the target object is determined according to the preset conversion rules between temperature and grayscale value and the target grayscale value.

[0112] Preferably, the preset component 520 includes a flange, and the detector is disposed on the outer surface of the flange or embedded in the flange.

[0113] Preferably, the infrared thermal imager further includes a lens 750, which is used to focus the infrared radiation emitted by the target object onto the detector.

[0114] Preferably, the processing device 540 can also be used to generate an initial temperature according to a preset conversion rule between temperature and grayscale value and the target grayscale value; and to determine the temperature of the target object according to a preset temperature compensation parameter corresponding to the distance between the infrared thermal imager and the target object and the initial temperature.

[0115] Preferably, the processing device 540 can also be used to determine the temperature of the target object based on the ambient humidity of the infrared thermal imager, the corresponding preset temperature compensation parameters, and the initial temperature.

[0116] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to the method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0117] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A calibration method for an infrared thermal imager, characterized in that, The method includes: The initial grayscale value of the target object acquired by the infrared thermal imager is obtained, and the difference between the acquisition time of the initial grayscale value and the power-on time of the infrared thermal imager does not exceed a preset time threshold. Obtain the measured temperature value from the infrared thermal imager; According to the preset calculation rules, the grayscale value adjustment value corresponding to the temperature value is determined; wherein, the grayscale value adjustment value is determined by the grayscale value change coefficient and the preset time value, and the grayscale value adjustment value is obtained according to Delta_T_flange*K, where Delta_T_flange is the preset time value and K is the grayscale value change coefficient corresponding to each temperature value; A target grayscale value is generated based on the grayscale adjustment value and the initial grayscale value, wherein the target grayscale value is represented by C_object_initial+Delta_T_flange*K, and C_object_initial represents the initial grayscale value; The temperature of the target object is determined according to the preset conversion rules between temperature and grayscale value and the target grayscale value.

2. The method according to claim 1, characterized in that, The initial grayscale value of the target object acquired by the infrared thermal imager includes: The initial grayscale value of the target object is determined based on the infrared radiation collected by the detector of the infrared thermal imager. The temperature value obtained from the infrared thermal imager includes: The temperature value of a preset component is obtained by measurement, and the detector is installed on the preset component.

3. The method according to claim 1 or 2, characterized in that, Determining the temperature of the target object based on a preset temperature-grayscale value conversion rule and the target grayscale value includes: An initial temperature is generated based on the preset conversion rules between temperature and grayscale values ​​and the target grayscale value. The temperature of the target object is determined based on the preset temperature compensation parameter corresponding to the distance between the infrared thermal imager and the target object, and the initial temperature.

4. The method according to claim 3, characterized in that, Determining the temperature of the target object based on a preset temperature compensation parameter corresponding to the distance between the infrared thermal imager and the target object, and the initial temperature, includes: The temperature of the target object is determined based on the ambient humidity of the infrared thermal imager, the corresponding preset temperature compensation parameters, and the initial temperature.

5. The method according to claim 1 or 2, characterized in that, The preset time threshold is 30 minutes.

6. A calibration device for an infrared thermal imager, characterized in that, The device includes: The acquisition module is used to acquire the initial grayscale value of the target object collected by the infrared thermal imager, wherein the difference between the acquisition time of the initial grayscale value and the power-on time of the infrared thermal imager does not exceed a preset time threshold; and to acquire the measured temperature value of the infrared thermal imager. The calculation module is used to determine the grayscale adjustment value corresponding to the temperature value according to preset calculation rules. The grayscale adjustment value is determined by the grayscale value change coefficient and a preset time value. The grayscale value change coefficient is determined by the temperature value. The grayscale adjustment value is obtained according to Delta_T_flange*K, where Delta_T_flange is the preset time value and K is the grayscale value change coefficient corresponding to each temperature value. A target grayscale value is generated based on the grayscale adjustment value and the initial grayscale value. The target grayscale value is represented by C_object_initial + Delta_T_flange*K, where C_object_initial represents the initial grayscale value. The judgment module is used to determine the temperature of the target object based on the preset conversion rules between temperature and grayscale value and the target grayscale value.

7. An infrared thermal imager, characterized in that, include: A detector used to collect infrared radiation from a target object; A preset component, wherein the detector is disposed on the preset component; A temperature sensor is used to collect the temperature value of the preset component; The processing device is used to determine the initial grayscale value of the target object based on the infrared radiation of the target object collected by the detector of the infrared thermal imager, wherein the difference between the infrared radiation collection time and the power-on time of the infrared thermal imager does not exceed a preset time threshold. Obtain the temperature value of the preset component collected by the temperature sensor; According to the preset calculation rules, the gray value adjustment value corresponding to the temperature value is determined. The gray value adjustment value is determined by the gray value change coefficient and the preset time value. The gray value change coefficient is determined by the temperature value. The gray value adjustment value is obtained according to Delta_T_flange*K, where Delta_T_flange is the preset time value and K is the gray value change coefficient corresponding to each temperature value. A target grayscale value is generated based on the grayscale adjustment value and the initial grayscale value, wherein the target grayscale value is represented by C_object_initial+Delta_T_flange*K, and C_object_initial represents the initial grayscale value; The temperature of the target object is determined according to the preset conversion rules between temperature and grayscale value and the target grayscale value.

8. The infrared thermal imager according to claim 7, characterized in that, The preset component includes a flange, and the detector is disposed on the outer surface of the flange or embedded in the flange.

9. The infrared thermal imager according to claim 7 or 8, characterized in that, The infrared thermal imager also includes a lens for focusing the infrared radiation emitted by the target object onto the detector.

10. The infrared thermal imager according to claim 7 or 8, characterized in that, The processing device can also be used to generate an initial temperature according to a preset conversion rule between temperature and grayscale value and the target grayscale value; and to determine the temperature of the target object according to a preset temperature compensation parameter corresponding to the distance between the infrared thermal imager and the target object and the initial temperature.

Images