Fast drift compensation method for infrared radiation calibration system

Abstract

The invention discloses a drift rapid compensation method used in an infrared radiation calibration system, which is characterized in that temperature drift and path attenuation are respectively corrected based on calibration of two environment temperatures and calibration of two test distances, and at least two values of three factors of black body temperature, environment temperature and test distance are respectively set; in a detector linear response interval of the infrared radiation calibration system, values of two factors are fixed, infrared image gray values of the black body when the third factor is in the two values are obtained, and at least four infrared image gray values are obtained; solving black body radiation brightness response, a temperature drift compensation coefficient, a distance drift coefficient and detector response bias by combining expression equations of four infrared image gray values; and according to a solving result, rapid compensation of gray value attenuation caused by the change of the environment temperature and the test distance is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of optics and photonics, relates to infrared radiation measurement, and particularly relates to a method for quickly compensating drift in an infrared radiation calibration system. Background Art

[0002] An infrared radiation calibration system is a system used to measure and analyze the infrared radiation emitted or reflected by an object, and can be used in applications such as temperature measurement, infrared imaging, and infrared spectroscopy analysis. The work of radiation calibration is to fit the relationship between the input infrared radiation and the output image gray value, obtain the corresponding calibration coefficient of the system, and further invert the incident radiation characteristics of the target according to the output image gray value.

[0003] During the calibration and measurement processes, changes in the ambient temperature will cause gray drift in the output of the infrared imaging system, restricting the accuracy of radiation measurement. Therefore, it is usually required that calibration and measurement be carried out under the same stable environmental conditions. In fact, the calibration process of the infrared system is often cumbersome, but the measurement task requires a short time, resulting in the inability to perform calibration and measurement simultaneously. Even due to field conditions, the calibration process can only be completed in the laboratory in advance. Therefore, the calibration duration is long, and the interval between calibration and measurement may also be long. The drift caused by temperature changes during the calibration process and the drift caused by the difference in ambient temperature between the calibration and measurement processes will both affect the radiation measurement accuracy. In addition, if the radiation measurement task lasts for a long time, the ambient temperature changes during this period will also affect the measurement accuracy, and the amount of gray drift at each moment is difficult to predict. In practical applications, a fixed calibration coefficient is used to quantitatively detect the target. Although the temperature of the target is weakly correlated with the imaging distance, as the imaging distance increases, its spectral recognition characteristics are extremely weak. If the traditional idea of radiation characteristic measurement is used and the same calibration parameters are used at different imaging distances, the temperature measurement error of the target will increase. Summary of the Invention

[0004] In order to overcome the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a method for quickly compensating drift in an infrared radiation calibration system to quickly compensate for the infrared image measurement error caused by temperature drift and measurement distance drift.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0006] A method for quickly compensating drift in an infrared radiation calibration system, which constructs the response output of the infrared radiation calibration system at different ambient temperatures, fixes the integration time of the infrared detection system, performs near-field extended source calibration on the infrared radiation calibration system at two ambient temperatures respectively, obtains two infrared image gray values, and solves them simultaneously to obtain the temperature drift compensation coefficient R s; Construct the response output of the infrared radiation calibration system at different test distances. Fix the integration time of the infrared detection system, perform extended source calibration on the infrared radiation calibration system at two test distances respectively, obtain two infrared image gray values, and solve them simultaneously to obtain the distance drift compensation coefficient R k ; According to the temperature drift compensation coefficient R s and the distance drift compensation coefficient R k , achieve rapid compensation for the gray value attenuation caused by changes in ambient temperature and test distance.

[0007] In one embodiment, the response output of the infrared radiation calibration system at different ambient temperatures is expressed as follows:

[0008] DN = R·L(T bb ) + R s ·L(T amb ) + DN dark

[0009] The response output of the infrared radiation calibration system at different test distances is expressed as follows:

[0010] DN = R·L(T bb ) + k·R k ·L(T bb ) + DN dark

[0011] In the formula, R is the blackbody radiation luminance response, T bb represents the target temperature, T amb represents the ambient temperature, k represents the test distance, L(T amb ) represents the radiation luminance when the ambient temperature is T amb , L(T bb ) represents the radiation luminance when the target temperature is T bb , and DN dark is the detector response bias of the infrared detection system.

[0012] In one embodiment, the two ambient temperatures are T amb1 and T amb2 , the two test distances are k 1 and k 2 , and the calculations of the temperature drift compensation coefficient R s and the distance drift compensation coefficient R k are as follows respectively:

[0013]

[0014] Among them, DN(T amb1 ) and DN(T amb2 ) respectively represent that the ambient temperatures are T amb1 and Tamb2 The corresponding infrared image gray value, DN(k 1 ), and DN(k 2 ) are the infrared image gray values corresponding to k 1 and k 2 respectively. L(T amb1 ), and L(T amb2 ) are the radiance corresponding to T amb1 and T amb2 respectively.

[0015] In one embodiment, the drift compensation values at different ambient temperatures are as follows:

[0016] ΔDN = R s ·[L(T amb ′) - L(T amb )]

[0017] The drift compensation values at different test distances are as follows:

[0018] ΔDN = R k ·Δk

[0019] In the formula, T amb ′ is the initial calibration ambient temperature, and Δk is the change value of the test distance.

[0020] The present invention also provides another fast drift compensation method for an infrared radiation calibration system, including the following steps:

[0021] Step 1: Set at least two values for each of the three factors of blackbody temperature, ambient temperature, and test distance;

[0022] Step 2: In the linear response range of the detector of the infrared radiation calibration system, fix the values of two of the factors, and obtain the infrared image gray values of the blackbody when the third factor takes two values, obtaining at least four infrared image gray values;

[0023] Step 3: Simultaneously solve the expression equations of the four infrared image gray values to obtain the blackbody radiance response R, the temperature drift compensation coefficient R s , the distance drift coefficient R k , and the detector response offset DN dark ;

[0024] Step 4: According to the solution results of Step 3, achieve fast compensation for the gray value attenuation caused by changes in ambient temperature and test distance.

[0025] In one embodiment, the two values of the set blackbody temperature are T bb1 and T bb2 , and the two values of the ambient temperature are T amb1 and T amb2, Two values of the test distance are k 1 and k 2 ;

[0026] In step 2, first fix T amb1 and k 1 , and obtain the gray values DN(T bb1 and T bb2 ) of the infrared image at T bb1 , T amb1 , k 1 ); then fix T bb2 and k amb1 , and obtain the gray value DN(T 1 ) of the infrared image at T bb2 ; finally, fix T 1 and T amb2 , and obtain the gray value DN(T bb2 , T amb2 , k 1 ) of the infrared image at k bb2 and T amb2 2 . bb2 , T, k amb2 , k 2 )

[0027] In one embodiment, each of the infrared image gray values is expressed as:

[0028] DN(T bb1 , T amb1 , k 1 ) = R·L(T bb1 ) + R s ·L(T amb1 ) + k 1 ·R k ·L(T bb1 ) + DN dark

[0029] DN(T bb2 , T amb1 , k 1 ) = R·L(T bb2 ) + R s ·L(T amb1 ) + k 1 ·R k ·L(T bb2 ) + DN dark

[0030] DN(T bb2 , T amb2 , k 1 ) = R·L(T bb2 ) + R s·L(T amb2 )+k 1 ·R k ·L(T bb2 )+DN dark

[0031] DN(T bb2 ,T amb2 ,k 2 )=R·L(T bb2 )+R s ·L(T amb2 )+k 2 ·R k ·L(T bb2 )+DN dark

[0032] In the formula, L(T bb1 ) and L(T bb2 ) are T bb1 and T bb2 The radiant brightness at the time, L(T amb1 ) and L(T amb2 ) are T amb1 and T amb2 The radiant brightness at .

[0033] In one embodiment, in step 3, the expression equations of the grayscale values ​​of the infrared images are combined to obtain the following solution:

[0034]

[0035] In one embodiment, in step 4, the radiant brightness of the target in any environment and test distance is:

[0036]

[0037] Where, T bb Indicates the target temperature, T amb represents the ambient temperature, k represents the test distance, L(T amb ) indicates that the ambient temperature is T amb The radiant brightness at the time, L(T bb ) indicates the target temperature is T bb The radiant brightness at .

[0038] Compared with the prior art, the present invention can improve the efficiency of compensation, obtain a calibration model, avoid excessively long calibration time, and reduce the influence of changes in ambient temperature and test distance on calibration, thereby improving the calibration and radiation measurement accuracy of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1Schematic diagram of the main components of the infrared radiation calibration system relied on for compensation.

[0040] Figure 2 Flow chart for temperature drift compensation and correction.

[0041] Figure 3 Flow chart for test distance compensation and correction.

[0042] Figure 4 Flow chart for system temperature drift and test distance compensation and correction. Specific implementation manner

[0043] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, 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 implementations described herein are only used to explain the present invention and are not used to limit the present invention.

[0044] The infrared radiation measurement system is one of the most important means for an optical range to obtain the radiation characteristics of a measured target, detect and identify the target early, and effectively evaluate the infrared band stealth effect. Infrared radiation calibration is the basis for completing infrared radiation characteristic measurement. Its purpose is to obtain its own response parameters (mainly including responsivity and self-bias response), so as to establish a quantitative relationship between the radiation amount output by the radiation source and the digital output gray value of the infrared radiation measurement system. As Figure 1 shown, the main structures relied on by the present invention for compensation include an infrared detection system, an optical system, a surface source blackbody, and an environmental thermometer. When the infrared radiation calibration system detects a target, the infrared radiation of the target and the background passes through the path and enters the optical system, and finally forms an image on the detector. The radiation characteristics of the target need to be inversely calculated and analyzed based on the infrared image gray value.

[0045] Based on two-environment temperature calibration and two-test distance calibration, the present invention corrects temperature drift and path attenuation respectively, and then proposes a fast drift compensation method for an infrared radiation calibration system.

[0046] The infrared radiation measurement system is significantly affected by the environmental temperature. Temperature drift refers to the change in the stray radiation inside the optical system caused by the change in the environmental temperature, which causes deviation in the output image gray value. Substantially, it is the change in the energy received by the detector target surface caused by the system temperature change due to the design defect of the infrared system. Temperature drift will affect the response bias coefficient of the calibration equation of the infrared radiation calibration system. Therefore, temperature drift compensation can be deduced through the infrared radiation calibration model at different environmental temperatures.

[0047] As a radiation source, factors such as the temperature distribution and surface emissivity of the opto-mechanical structure of the infrared radiation calibration system determine the magnitude of the spontaneous radiation energy. At the same time, as a reflective surface, the opto-mechanical structure also needs to consider factors such as its reflectivity and refractive index. Therefore, the internal stray radiation transmission mechanism is very complex, and a simplified model of stray radiation related to the ambient temperature needs to be established for analysis.

[0048] For a fixed infrared radiation calibration system, the effects of factors such as solid angle, reflectivity, and transmittance are fixed. Therefore, its simplified model of stray radiation (i.e., the radiation flux generated by internal stray radiation) can be expressed as the stray radiation flux Φ caused by the ambient temperature, as shown in the following equation. stary as follows.

[0049] Φ stary = R stary ·L λ (T amb ) (1)

[0050] In the formula, R stary represents the linear conversion factor that converts stray radiation luminance into stray radiation flux. For an infrared radiation calibration system with a fixed opto-mechanical structure, it can be regarded as a constant. L λ (T amb ) is the equivalent blackbody radiation luminance of the detector of the opto-mechanical structure of the infrared detection system at temperature T amb within its response band range. From the above simplified model of internal stray radiation of the infrared radiation calibration system, it can be seen that the stray radiation received by the detector is closely related to the ambient temperature, and the internal stray radiation generated by the infrared radiation calibration system is proportional to the equivalent blackbody radiation luminance of the ambient temperature T amb .

[0051] The deviation of the response bias coefficient of the infrared radiation calibration system mainly comes from the change of internal stray radiation. When considering stray radiation, the response output of the infrared radiation calibration system is established as shown in the following equation.

[0052] DN = R d ·(Φ tar + Φ stary ) + DN dark (2)

[0053] In the formula, DN is the gray value of the infrared image of the response output, R d is the response gain of the detector to the incident radiation flux, Φ tar is the radiation flux of the measurement target, and DN dark is the background noise charge generated by the detector when there is no incident radiation, that is, the detector response bias of the infrared detection system. When the blackbody is used as the measurement target, the relationship between its radiation flux and radiation luminance is

[0054] Φ bb = K bb ·L(T bb )(3)

[0055] Wherein, K bb is a constant, and L(T bb ) represents the radiance at the target temperature of T bb .

[0056] Similarly, the relationship between the radiation flux generated by the stray radiation inside the infrared radiation calibration system and the equivalent blackbody radiance of the ambient temperature is

[0057] Φ stary = K amb ·L(T amb )(4)

[0058] Wherein, K amb is a constant, and L(T amb ) represents the radiance at the ambient temperature of T amb .

[0059] Combined with the stray radiation simplified model, formula (2) can be rewritten as the following formula.

[0060] DN = R·L(T bb ) + R s ·L(T amb ) + DN dark (5)

[0061] Wherein, R = R d ·K bb , which is the blackbody radiance response, representing the gain of the detector in the infrared detection system to the radiance L(T bb ). R s = R d ·K amb , which is the temperature drift compensation coefficient, representing the gain of the detector in the infrared detection system to the radiance L(T amb ).

[0062] Formula (5) is the radiation calibration model considering the ambient temperature in the infrared radiation calibration system. It can be seen that the gray value of the image is related to three parts of the response: the target radiance related to the target temperature, the internal stray radiation of the system related to the ambient temperature, and the noise signal of the detector itself. To compensate for the gray value caused by temperature drift, it is necessary to first calculate the temperature drift compensation coefficient R s .

[0063] Based on the above, the present invention constructs a temperature drift compensation model based on calibration at two ambient temperatures, such as Figure 2As shown, first fix the integration time of the infrared detection system and set the ambient temperature to T amb1 , the infrared radiation calibration system is calibrated for close-range extended source, and the grayscale value of the infrared image output is:

[0064] DN(T amb1 )=R·L(T bb )+R s ·L(T amb1 )+DN dark (6)

[0065] Then, change the ambient temperature from T amb1 Change to T amb2 , the infrared radiation calibration system is calibrated for close-range extended source, and the grayscale value of the infrared image output is:

[0066] DN(T amb2 )=R·L(T bb )+R s ·L(T amb2 )+DN dark (7)

[0067] Combining the above two formulas, we get the temperature drift compensation coefficient R s The expression is as follows:

[0068]

[0069] Where DN(T amb1 ) and DN(T amb2 ) are T amb1 and T amb2 The corresponding infrared image grayscale value, L(T amb1 ) and L(T amb2 ) are T amb1 and T amb2 The corresponding radiance.

[0070] The drift compensation value at different ambient temperatures is as follows:

[0071] ΔDN=R s ·[L(T amb ′)-L(T amb )] (9)

[0072] Where, T amb ′ is the initial calibration ambient temperature.

[0073] Meanwhile, the change in the test distance between the target under test and the infrared radiation calibration system will also cause changes in the radiation reaching the detector, which will ultimately be reflected in the grayscale value deviation. Therefore, the radiation attenuation can be deduced through the infrared radiation calibration model, and then the radiation luminance of the target under test can be calculated.

[0074] When radiation propagates in a medium, due to medium absorption and scattering, the radiation flux φ of the target will decay. Assuming that the medium only has an absorption effect on radiation, when a parallel radiation beam propagates a distance of k in a homogeneous medium, the relative value ΔΦ / Φ of the radiation flux ΔΦ absorbed by the medium is proportional to the passed path Δk, that is where α is the absorption coefficient of the medium. Therefore, the change in the test distance will cause changes in the radiation reaching the detector, which will ultimately be reflected in the grayscale value deviation. The higher the temperature of the calibration data points, the greater the error between the calibration data, and the greater the data error at the same temperature point with the increase of distance. With the increase of distance, the gain response parameter and bias response parameter of the calibration change. The gain parameter decreases with the increase of distance, which also indicates that the air on the imaging path has a certain attenuation effect on infrared radiation.

[0075] Therefore, for different test distances, distance correction can be carried out through calibration. From the above formula, we can get Δφ = -α·Δk / k·φ by deformation. Furthermore, we can draw the conclusion that when changing the test distance, the change amount of its radiation flux is jointly determined by the medium absorption coefficient and the radiation flux.

[0076] As Figure 3 shown, to compensate for the change in the grayscale value of the infrared image caused by the change in distance, it is necessary to first calculate the change amount of the grayscale value caused by the change in distance theoretically. Therefore, the response output of infrared radiation at different test distances is established according to the above formula as follows:

[0077] DN = R·L(T bb ) + k·R k ·L(T bb ) + DN dark (10)

[0078] In the formula, R k is the attenuation compensation coefficient of the radiation flux varying with distance, that is, the distance drift coefficient, and k is the test distance. It can be seen from the formula that the key to establishing the infrared radiation calibration model at different test distances lies in the solution of R k .

[0079] First, set the test distance as k 1 under a fixed integration time, and perform extended source calibration on the infrared radiation calibration system. The grayscale value of the infrared image output by the response is:

[0080] DN(k 1 ) = R·L(Tbb ) + k 1 ·R k ·L(T bb ) + DN dark (11)

[0081] Then, keeping the integration time the same, the test distance changes from k 1 to k 2 , and the extended source calibration of the infrared radiation calibration system is carried out. The gray value of the output infrared image of the response is:

[0082] DN(k 2 ) = R·L(T bb ) + k 2 ·R k ·L(T bb ) + DN dark (12)

[0083] Combining the above two formulas, the distance drift compensation coefficient R k is shown as follows:

[0084]

[0085] where DN(k 1 ) and DN(k 2 ) are the gray values of the infrared images corresponding to k 1 and k 2 respectively. Therefore, the drift compensation values at different test distances are shown as follows.

[0086]

[0087] In the formula, Δk is the change value of the test distance.

[0088] Although the above temperature drift and distance drift measurement and compensation method based on calibration can meet the drift compensation requirements, it is necessary to collect a large number of calibration images one by one at the preset integration time, and then perform fitting analysis. The workload is large, the operation is cumbersome, the efficiency is low, the consumption is long, and the real-time performance is poor.

[0089] Therefore, the present invention further proposes a fast temperature drift and measurement distance drift measurement compensation method to improve the compensation efficiency, avoid too long calibration time, reduce the influence of environmental temperature and test distance changes on calibration, and thus improve the calibration and radiation measurement accuracy of the system.

[0090] Based on the foregoing, when considering the environmental temperature and the test distance, the infrared radiation calibration model is shown as follows:

[0091] DN(T bb , T amb , k) = R·L(Tbb ) + R s ·L(T amb ) + k·R k ·L(T bb ) + DN dark (15)

[0092] The above calibration equation has four unknown parameters, namely the blackbody radiation luminance response R, the temperature drift compensation coefficient R s , the distance drift coefficient R k and the detector response bias DN dark . Therefore, at least four equations are required to solve the relevant calibration parameters and complete the measurement and compensation of drift. As Figure 4 shown, the specific process is as follows:

[0093] Step 1, in the linear response range of the detector, set the blackbody temperature to T bb1 , the ambient temperature to T amb1 , and the test distance to k 1 . Then, according to the above formula (15), the gray value DN(T bb1 , T amb1 , k 1 ) of the collected infrared image is expressed as:

[0094] DN(T bb1 , T amb1 , k 1 ) = R·L(T bb1 ) + R s ·L(T amb1 ) + k 1 ·R k ·L(T bb1 ) + DN dark (16)

[0095] Step 2, change the blackbody temperature from T bb1 to T bb2 , keep the ambient temperature as T amb1 , and keep the test distance as k 1 . Then, according to the above formula, the gray value DN(T bb2 , T amb1 , k 1 ) of the collected infrared image is expressed as:

[0096] DN(T bb2 , T amb1 , k 1 ) = R·L(T bb2 ) + R s ·L(T amb1 ) + k 1 ·R k ·L(Tbb2 )+DN dark (17)

[0097] Step 3: Keep the blackbody temperature at T bb2 , the ambient temperature is determined by T amb1 Change to T amb2 , the test distance is kept as k 1 , then according to the above formula, the gray value DN(T bb2 ,T amb2 ,k 1 ) is expressed as:

[0098] DN(T bb2 ,T amb2 ,k 1 )=R·L(T bb2 )+R s ·L(T amb2 )+k 1 ·R k ·L(T bb2 )+DN dark (18)

[0099] Step 4: Keep the blackbody temperature at T bb2 , the ambient temperature is maintained at T amb2 , the test distance is k 1 becomes k 2 , then according to the above formula, the gray value DN(T bb2 ,T amb2 ,k 2 ) is expressed as:

[0100] DN(T bb2 ,T amb2 ,k 2 )=R·L(T bb2 )+R s ·L(T amb2 )+k 2 ·R k ·L(T bb2 )+DN dark (19)

[0101] Step 5: By collecting the above four calibration images, four equations can be obtained to solve four unknown parameters, and the combined formula is:

[0102]

[0103] Solved by the inverse operation of the matrix:

[0104]

[0105] According to the solution results of the above formula, the blackbody calibration equation at any ambient temperature and any test distance can be obtained, realizing the rapid measurement and compensation of the gray value attenuation caused by the changes in ambient temperature and test distance. Therefore, the radiance of the target under any environment and test distance is:

[0106]

Claims

1. A method for rapid drift compensation in an infrared radiation calibration system, characterized in that: The response output of the infrared radiation calibration system under different ambient temperatures is constructed, the integration time of the infrared detection system is fixed, and the infrared radiation calibration system is calibrated at close range and extended source under two ambient temperatures to obtain two infrared image grayscale values. The temperature drift compensation coefficient R is obtained by simultaneous solution. s ; The response output of the infrared radiation calibration system at different test distances is constructed, the integration time of the infrared detection system is fixed, and the infrared radiation calibration system is calibrated with an extended source at two test distances to obtain two infrared image grayscale values. The distance drift compensation coefficient R is obtained by simultaneous solution. k ; According to the temperature drift compensation coefficient R s and distance drift compensation coefficient R k , to achieve rapid compensation for grayscale value attenuation caused by changes in ambient temperature and test distance.

2. The method for rapid drift compensation in an infrared radiation calibration system according to claim 1, characterized in that: The response output of the infrared radiation calibration system at different ambient temperatures is expressed as follows: DN=R·L(T bb )+R s ·L(T amb )+DN dark The response output of the infrared radiation calibration system at different test distances is expressed as follows: DN=R·L(T bb )+k·R k ·L(T bb )+DN dark Where R is the blackbody radiation brightness response, T bb Indicates the target temperature, T amb represents the ambient temperature, k represents the test distance, L(T amb ) indicates that the ambient temperature is T amb The radiant brightness at the time, L(T bb ) indicates the target temperature is T bb Radiance at DN dark Bias the detector response for infrared detection systems.

3. The method for rapid drift compensation in an infrared radiation calibration system according to claim 2, characterized in that: The two ambient temperatures are T amb1 and T amb2 , the two test distances are k1 and k2, the temperature drift compensation coefficient R s and distance drift compensation coefficient R k The calculations are as follows: Where DN(T amb1 ) and DN(T amb2 ) are T amb1 and T amb2 The corresponding infrared image grayscale values, DN(k1) and DN(k2) are the infrared image grayscale values ​​corresponding to k1 and k2 respectively, L(T amb1 ) and L(T amb2 ) are T amb1 and T amb2 The corresponding radiance.

4. The method for rapid drift compensation in an infrared radiation calibration system according to claim 3, characterized in that: The drift compensation value under different ambient temperatures is as follows: ΔDN=R s ·[L(T amb ′)-L(T amb )] The drift compensation value at different test distances is as follows: ΔDN=R k ·Δk Where, T amb ′ is the initial calibration ambient temperature, and Δk is the test distance change value.

5. A method for rapid drift compensation in an infrared radiation calibration system, characterized in that: The steps include: Step 1, setting the black body temperature, ambient temperature and test distance to have at least two values ​​respectively; Step 2, in the linear response range of the detector of the infrared radiation calibration system, fix the values ​​of two of the factors, obtain the infrared image grayscale values ​​of the black body when the third factor takes two values, and obtain at least four infrared image grayscale values; Step 3: Combine the four infrared image grayscale value expression equations to solve the blackbody radiation brightness response R and the temperature drift compensation coefficient R s , distance drift coefficient R k and the detector response bias DN dark ; Step 4: Based on the solution of step 3, a quick compensation for the gray value attenuation caused by the change of ambient temperature and test distance is achieved.

6. The method for rapid drift compensation in an infrared radiation calibration system according to claim 5, characterized in that: Set the blackbody temperature to T bb1 and T bb2 , the two values ​​of ambient temperature are T amb1 and T amb2 , the two values ​​of the test distance are k1 and k2; In step 2, first fix T amb1 and k1, we get T bb1 and T bb2 The gray value of the infrared image DN(T bb1 ,T amb1 ,k1) and DN(T bb2 ,T amb1 ,k1); then fix T bb2 and k1, we get T amb2 The gray value of the infrared image DN(T bb2 ,T amb2 ,k1); finally fix T bb2 and T amb2 , get the infrared image gray value DN(T bb2 ,T amb2 ,k2).

7. The method for rapid drift compensation in an infrared radiation calibration system according to claim 6, characterized in that: The grayscale value of each infrared image is expressed as: DN(T bb1 ,T amb1 ,k1)=R·L(T bb1 )+R s ·L(T amb1 )+k1·R k ·L(T bb1 )+DN dark DN(T bb2 ,T amb1 ,k1)=R·L(T bb2 )+R s ·L(T amb1 )+k1·R k ·L(T bb2 )+DN dark DN(T bb2 ,T amb2 ,k1)=R·L(T bb2 )+R s ·L(T amb2 )+k1·R k ·L(T bb2 )+DN dark DN(T bb2 ,T amb2 ,k2)=R·L(T bb2 )+R s ·L(T amb2 )+k2·R k ·L(T bb2 )+DN dark In the formula, L(T bb1 ) and L(T bb2 ) are T bb1 and T bb2 The radiant brightness at the time, L(T amb1 ) and L(T amb2 ) represents the ambient temperature respectively T amb1 and T amb2 The radiant brightness at .

8. The method for rapid drift compensation in an infrared radiation calibration system according to claim 7, characterized in that: In step 3, the expression equations of the grayscale values ​​of the infrared images are combined to obtain the following solution:

9. The method for rapid drift compensation in an infrared radiation calibration system according to claim 8, characterized in that: In step 4, the radiant brightness of the target in any environment and test distance is: Where, T bb Indicates the target temperature, T amb represents the ambient temperature, k represents the test distance, L(T amb ) indicates that the ambient temperature is T amb The radiant brightness at the time, L(T bb ) indicates the target temperature is T bb The radiant brightness at .

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