A method and apparatus for infrared measurement calibration under varying ambient temperature

Abstract

This invention relates to the field of infrared measurement technology, and particularly to an infrared measurement calibration method and apparatus for varying ambient temperatures. The infrared measurement calibration method for varying ambient temperatures includes: placing a blackbody in a constant temperature chamber, filling the field of view of an infrared measurement system with the radiating surface of the blackbody; collecting response data of each pixel of the infrared measurement system to the constant temperature chamber and the blackbody at different temperatures of the constant temperature chamber and the blackbody; wherein, at each temperature of the constant temperature chamber, there are multiple blackbody temperatures; establishing a response matrix based on the temperature of the constant temperature chamber, the temperature of the blackbody, and the response data; calculating calibration coefficients based on the response matrix; and calculating the temperature and brightness of the target object under varying ambient temperatures based on the calibration coefficients. This invention provides an infrared measurement calibration method and apparatus for varying ambient temperatures, capable of accurately measuring the temperature and brightness of a target object under changing ambient temperatures.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of infrared measurement technology, and particularly relates to an infrared measurement calibration method and device under variable ambient temperature. BACKGROUND

[0002] The infrared measurement system is widely used in the measurement of temperature, brightness and other parameters. However, in the case of large change of ambient temperature, the error of the measurement result is large.

[0003] Therefore, in view of the above problems, there is an urgent need for an infrared measurement calibration method and device under variable ambient temperature. SUMMARY

[0004] The present application provides an infrared measurement calibration method and device under variable ambient temperature, which can measure the temperature and brightness of the target object in the case of large change of ambient temperature.

[0005] The present application provides an infrared measurement calibration method under variable ambient temperature, comprising:

[0006] Placing a black body in a thermostat, and filling the field of view of the infrared measurement system with the radiation surface of the black body;

[0007] Collecting the response data of each pixel of the infrared measurement system to the thermostat and the black body under different thermostat temperatures and different black body temperatures; wherein, under the temperature of each thermostat, there are multiple black body temperatures;

[0008] Establishing a response matrix according to the temperature of the thermostat, the temperature of the black body and the response data;

[0009] Calculating the calibration coefficient according to the response matrix;

[0010] Calculating the temperature and brightness of the target to be measured under variable ambient temperature according to the calibration coefficient.

[0011] In a possible design, collecting the response data of each pixel of the infrared measurement system to the thermostat and the black body under different thermostat temperatures and different black body temperatures comprises:

[0012] Controlling the thermostat temperature to be a constant temperature, and collecting the response data of each pixel of the infrared measurement system to the thermostat and the black body under different black body temperatures; wherein, the values of the multiple black body temperatures are continuously distributed in an arithmetic sequence;

[0013] The following steps are performed at least once: changing the constant temperature of the constant temperature chamber, and collecting response data of each pixel of the infrared measurement system to the constant temperature chamber and the blackbody at different temperatures of the blackbody; wherein the values ​​of multiple blackbody temperatures and multiple constant temperatures are continuously distributed in an arithmetic sequence.

[0014] In one possible design, establishing the response matrix based on the temperature of the constant temperature chamber, the temperature of the blackbody, and the response data includes:

[0015] Establish a parameter matrix based on the temperature of the constant temperature chamber and the temperature of the blackbody;

[0016] A response matrix is ​​established based on the response data and the parameter matrix.

[0017] In one possible design, the response data is:

[0018] h i，j (TT N TB M )

[0019] Where h is the response data, i is the x-coordinate of the pixel in the image, j is the y-coordinate of the pixel in the image, and TB M The temperature of the constant temperature chamber is M, and the number of constant temperature chambers is TT. N Let N be the temperature of the blackbody, and N be the number of blackbody temperatures at each of the constant temperatures.

[0020] In one possible design, the parameter matrix is:

[0021]

[0022] Where L is the parameter matrix, TB M The temperature of the constant temperature chamber is M, and the number of constant temperature chambers is TT. N Let N be the temperature of the blackbody, and L(TT) be the number of blackbody temperatures at each of the isothermal temperatures. M Let L(TT) be the radiance at the M constant temperatures, and L(TT) be the radiance at the M constant temperatures. N ) represents the radiance at N blackbody temperatures.

[0023] In one possible design, the response matrix is:

[0024]

[0025] Where H is the response matrix, i is the x-coordinate of the pixel in the image, j is the y-coordinate of the pixel in the image, and TB M The temperature of the constant temperature chamber is M, and the number of constant temperature chambers is TT.N is the temperature of the blackbody, N is the number of the blackbody temperature at each constant temperature, and T is the temperature of the blackbody.

[0026] In a possible design, the calculating the calibration coefficient according to the response matrix comprises:

[0027] X i,j = (a i,j ,b i,j ,c i,j ) T = (L T L) -1 L T H i,j

[0028] wherein X is the calibration coefficient, a is the first calibration coefficient, b is the second calibration coefficient, c is the third calibration coefficient, H is the response matrix, i is the horizontal coordinate of a pixel in an image, j is the vertical coordinate of the pixel in the image, and L is the parameter matrix.

[0029] In a possible design, the calculating the temperature and brightness of the target to be measured under the variable environment temperature according to the calibration coefficient comprises:

[0030] The temperature and brightness of the target to be measured under the variable environment temperature are calculated according to the calibration coefficient by using the following formula,

[0031] L i,j (TT) = (h i,j (TT,TB)-b i,j L(TB)-c i,j ) / a i,j

[0032] wherein h is the response data, a is the first calibration coefficient, b is the second calibration coefficient, c is the third calibration coefficient, i is the horizontal coordinate of a pixel in an image, j is the vertical coordinate of the pixel in the image, L(TT) is the brightness of the target to be measured, TT is the temperature of the target to be measured, L(TB) is the environment brightness, and TB is the environment temperature.

[0033] The embodiment of the present application further provides an infrared measuring device under a variable environment temperature, which is used for implementing the method in any one of the above embodiments, and comprises a constant temperature box, a blackbody, an infrared measuring system and an acquisition computer.

[0034] The constant temperature box is used for providing a constant temperature.

[0035] The blackbody is placed in the constant temperature box and is used for releasing radiation.

[0036] The infrared measuring system is used for acquiring the temperature and response data of the blackbody and the constant temperature box.

[0037] The acquisition computer is configured to receive the temperature and the response data of the infrared measurement system.

[0038] In one possible design, a temperature sensor is arranged on a lens of the infrared measurement system, and the temperature sensor is configured to measure an ambient temperature.

[0039] Compared with the prior art, the present application has at least the following beneficial effects:

[0040] In the embodiment, in order to measure the temperature and the brightness of the target to be measured by using the infrared measurement method in an area where the ambient temperature changes greatly, a black body is first placed in a thermostat, and the response data of the infrared measurement system under different thermostat temperatures and different black body temperatures are collected. A response matrix is established according to the temperature of the thermostat, the temperature of the black body and the response data, and a calibration coefficient can be calculated through the response matrix. The calibration coefficient and the response matrix can be applied to any detection target of the infrared measurement system, and the brightness and the temperature of any target to be measured can be deduced through the calibration coefficient combined with the response matrix. BRIEF DESCRIPTION OF DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0042] Figure 1 is a flow chart of an infrared measurement calibration method provided by an embodiment of the present application;

[0043] Figure 2 is a structural schematic diagram of an infrared measurement device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0044] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will combine the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0045] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance; unless otherwise specified or stated, the term "plurality" means two or more; the terms "connection", "fixation" and the like shall be interpreted broadly, for example, "connection" can be fixed connection, or detachable connection, or integrally connected, or electrically connected; it can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0046] In the description of the present specification, it should be understood that the "upper", "lower" and the like described in the embodiments of the present application are described from the angle shown in the drawings, and should not be understood as limiting the embodiments of the present application. In addition, in the context, it should also be understood that when referring to one element connected to another element "on" or "below", it can not only be directly connected to another element "on" or "below", but also indirectly connected to another element "on" or "below" through an intermediate element.

[0047] As Figure 1 shown, the embodiments of the present application provide an infrared measurement calibration method for changing environment temperature, comprising:

[0048] S1, placing a black body in a thermostat, and filling the field of view of the infrared measurement system with the radiation surface of the black body;

[0049] S2, collecting the response data of each pixel of the infrared measurement system to the thermostat and the black body under different thermostat temperatures and different black body temperatures; wherein, under the temperature of each thermostat, there are multiple black body temperatures;

[0050] S3, establishing a response matrix according to the temperature of the thermostat, the temperature of the black body and the response data;

[0051] S4, calculating the calibration coefficient according to the response matrix;

[0052] S5, calculating the temperature and brightness of the target to be measured under the changing environment temperature according to the calibration coefficient.

[0053] In the present embodiment, in order to measure the temperature and brightness of the target to be measured in a large area with changing environment temperature by using infrared detection method, a black body is placed in a thermostat, and the response data of the infrared measurement system under different thermostat temperatures and different black body temperatures is collected. A response matrix is established according to the temperature of the thermostat, the temperature of the black body and the response data, and the calibration coefficient can be calculated through the response matrix. The calibration coefficient and the response matrix can be applied to any detection target of the infrared measurement system, and the brightness and temperature of any target to be measured can be deduced through the calibration coefficient combined with the response matrix.

[0054] In some embodiments of the present application, the response data of each pixel of the infrared measurement system to the thermostat and the black body at different thermostat temperatures and different black body temperatures are collected, including:

[0055] The response data of each pixel of the infrared measurement system to the thermostat and the black body at different black body temperatures are collected when the thermostat temperature is constant; wherein the values of the plurality of black body temperatures are continuously distributed in an arithmetic sequence.

[0056] At least the following step is performed: changing the constant temperature of the thermostat, collecting the response data of each pixel of the infrared measurement system to the thermostat and the black body at different black body temperatures; wherein the values of the plurality of black body temperatures and the plurality of constant temperatures are continuously distributed in an arithmetic sequence.

[0057] In this embodiment, the temperature of the black body and the constant temperature of the thermostat are in an arithmetic sequence, which has good continuity, and the response data obtained is more accurate. In addition, the more the temperature of the black body and the constant temperature of the thermostat, the smaller the temperature difference between different temperatures, and the more the response data obtained, and the more accurate the brightness and temperature measured by reverse calculation.

[0058] It should be noted that at least two constant temperatures are collected, and at least two black body temperatures are collected at each constant temperature.

[0059] In some embodiments of the present application, a response matrix is established according to the temperature of the thermostat, the temperature of the black body and the response data, including:

[0060] A parameter matrix is established according to the temperature of the thermostat and the temperature of the black body;

[0061] A response matrix is established according to the response data and the parameter matrix.

[0062] In this embodiment, the parameter matrix is first established according to the temperature of the thermostat and the temperature of the black body, and then the response matrix is established according to the response data and the parameter matrix.

[0063] In some embodiments of the present application, the response data is:

[0064] h i，j (TT N , TB M )

[0065] Wherein h is the response data, i is the horizontal coordinate of the pixel in the image, j is the vertical coordinate of the pixel in the image, TB M is the temperature of the thermostat, M is the number of constant temperatures, TT N is the temperature of the black body, and N is the number of black body temperatures at each constant temperature.

[0066] In the embodiment, each pixel has a set of response data corresponding thereto, and the response data includes blackbody temperature and thermostat temperature.

[0067] In some embodiments of the present application, the parameter matrix is:

[0068]

[0069] wherein L is the parameter matrix, TB M is the temperature of the thermostat, M is the number of thermostat temperatures, TT N is the temperature of the blackbody, N is the number of blackbody temperatures under each thermostat temperature, L(TT M ) is the radiation brightness under M thermostat temperatures, and L(TT N ) is the radiation brightness under N blackbody temperatures.

[0070] In some embodiments of the present application, the response matrix is:

[0071]

[0072] wherein H is the response matrix, i is the horizontal coordinate of the pixel in the image, j is the vertical coordinate of the pixel in the image, TB M is the temperature of the thermostat, M is the number of thermostat temperatures, TT N is the temperature of the blackbody, and N is the number of blackbody temperatures under each thermostat temperature.

[0073] In some embodiments of the present application, the calibration coefficient is calculated according to the response matrix, comprising:

[0074] X i,j = (a i,j ,b i,j ,c i,j ) T = (L T L) -1 L T H i,j

[0075] wherein X is the calibration coefficient, a is the first calibration coefficient, b is the second calibration coefficient, c is the third calibration coefficient, H is the response matrix, i is the horizontal coordinate of the pixel in the image, j is the vertical coordinate of the pixel in the image, and L is the parameter matrix.

[0076] In some embodiments of the present application, the temperature and brightness of the target to be measured under the variable environment temperature are calculated according to the calibration coefficient, comprising:

[0077] The temperature and brightness of the target to be measured under the variable environment temperature are calculated according to the calibration coefficient by using the following formula,

[0078] L i,j(TT) = (h i,j (TT,TB)-b i,j L(TB)-c i,j ) / a i,j

[0079] wherein h is the response data, a is the first calibration coefficient, b is the second calibration coefficient, c is the third calibration coefficient, i is the horizontal coordinate of the pixel in the image, j is the vertical coordinate of the pixel in the image, L(TT) is the brightness of the target to be measured, TT is the temperature of the target to be measured, L(TB) is the ambient brightness, and TB is the ambient temperature.

[0080] In the embodiment, h, TB, a, b, and c are known parameters, wherein TB is measured by an ambient temperature sensor.

[0081] In the embodiment, the radiant brightness of L(TT) and L(TB) can be calculated by the Planck formula and wherein λ is the wavelength (μm), λ1 and λ2 are the lower and upper cut-off wavelengths of the detection spectrum range, C1 = 37415 is the first radiation constant, and C2 = 14388 is the first radiation constant.

[0082] It should be noted that the values of L(TT N ) and L(TB M ) can also be calculated by the Planck formula.

[0083] As shown in Figure 2 , the embodiment of the present application further provides an infrared measurement device with variable ambient temperature, which is used to implement the method of any one of the above, and comprises a thermostat, a black body, an infrared measurement system, and an acquisition computer.

[0084] The thermostat is used to provide a constant temperature.

[0085] The black body is placed in the thermostat and is used to release radiation.

[0086] The infrared measurement system is used to acquire the temperature and response data of the black body and the thermostat.

[0087] The acquisition computer is used to receive the temperature and response data of the infrared measurement system.

[0088] In the embodiment, the infrared measurement device with variable ambient temperature and the above method are based on the same inventive concept, and thus can achieve the same beneficial effects, which are described in detail in the above method embodiment and will not be described here.

[0089] In some embodiments of the present application, a temperature sensor is arranged on the lens of the infrared measurement system, and the temperature sensor is used to measure the ambient temperature.

[0090] In the present embodiment, the temperature sensor measures the ambient temperature, which is used to calculate the brightness and temperature of the target to be measured.

[0091] Embodiment

[0092] 1. The following model is established based on the transformed temperature and the infrared radiation temperature.

[0093] h i,j (TT, TB) = a i,j L(TT) + b i,j L(TB) + c i,j

[0094] 2. The minimum is two ambient temperatures, three response points at two blackbody temperatures.

[0095] h i,j (TT1, TB1) = a i,j L(TT1) + b i,j L(TB1) + c i,j

[0096] h i,j (TT2, TB1) = a i,j L(TT2) + b i,j L(TB1) + c i,j

[0097] h i,j (TT2, TB2) = a i,j L(TT2) + b i,j L(TB2) + c i,j

[0098]

[0099] Simplify H i,j = LX i,j , where,

[0100]

[0101] Given the response H at two blackbody temperatures TT1 and TT2 of TB1 and TB2 at two ambient temperatures i,j , the radiometric brightness L(TT) and L(TB) can be calculated by the Planck formula and where λ is the wavelength in μm, λ1 and λ2 are the lower and upper cutoff wavelengths of the detection spectral range. C1 = 37415 is the first radiation constant and C2 = 14388 is the first radiation constant.

[0102] Direct solution can obtain model coefficients X i,j = (a i,j , bi,j i,j T

[0103] X i,j = (L T L) -1 L T H i,j

[0104] The infrared measurement system detects any target to be measured according to the coefficient and response matrix.

[0105] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application, and are not intended to limit the same; although the present application has been described in detail with reference to the foregoing examples, those of ordinary skill in the art will understand that they can still modify the technical solutions recorded in the foregoing examples, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.​​

Claims

1. A method for infrared measurement calibration under varying ambient temperature, characterized in that, include: A blackbody is placed in a constant temperature chamber, and the radiating surface of the blackbody fills the field of view of the infrared measurement system. At different temperatures of the constant temperature chamber and at different temperatures of the blackbody, the response data of each pixel of the infrared measurement system to the constant temperature chamber and the blackbody are collected; wherein, at each temperature of the constant temperature chamber, there are multiple blackbody temperatures; A response matrix is ​​established based on the temperature of the constant temperature chamber, the temperature of the blackbody, and the response data. Calculate the calibration coefficients based on the response matrix; Calculate the temperature and brightness of the target under varying ambient temperatures based on the calibration coefficients. The response data of each pixel of the infrared measurement system to the constant temperature chamber and the blackbody are collected under different temperatures of the constant temperature chamber and different temperatures of the blackbody, including: The temperature of the constant temperature chamber is controlled to a constant temperature, and the response data of each pixel of the infrared measurement system to the constant temperature chamber and the blackbody are collected at different temperatures of the blackbody; wherein, the values ​​of multiple blackbody temperatures are continuously distributed in an arithmetic sequence; The following steps are performed at least once: changing the constant temperature of the constant temperature chamber, and collecting response data of each pixel of the infrared measurement system to the constant temperature chamber and the blackbody at different temperatures of the blackbody; wherein the values ​​of multiple blackbody temperatures and multiple constant temperatures are continuously distributed in an arithmetic sequence. The step of establishing a response matrix based on the temperature of the constant temperature chamber, the temperature of the blackbody, and the response data includes: Establish a parameter matrix based on the temperature of the constant temperature chamber and the temperature of the blackbody; Establish a response matrix based on the response data and the parameter matrix; The response data is as follows: Where h is the response data, i is the x-coordinate of the pixel in the image, j is the y-coordinate of the pixel in the image, and TB M The temperature of the constant temperature chamber is M, and the number of constant temperature chambers is TT. N Let N be the temperature of the blackbody, and N be the number of blackbody temperatures at each of the constant temperatures. The parameter matrix is: in, L For the parameter matrix, TB M The temperature of the constant temperature chamber, M The number of constant temperatures. TT N The temperature of the blackbody. N The number of blackbody temperatures at each of the stated constant temperatures. L ( TT M )for M Radiance at the stated constant temperature L ( TT N )for N Radiance at the blackbody temperature; and The radiance is calculated using Planck's formula: and ,in For wavelength, and To detect the lower and upper cutoff wavelengths of the spectral range, C1=37415 is the first radiation constant and C2=14388 is the second radiation constant; The response matrix is: in, H The response matrix, i The x-coordinate of the pixel in the image. j represents the ordinate of the pixel in the image. TB M The temperature of the constant temperature chamber, M The number of constant temperatures. TT N The temperature of the blackbody. N The number of blackbody temperatures at each of the stated constant temperatures; The calculation of calibration coefficients based on the response matrix includes: in, X For calibration coefficients, a The first calibration coefficient, b This is the second calibration coefficient. c This is the third calibration coefficient. H The response matrix, i The x-coordinate of the pixel in the image. j represents the ordinate of the pixel in the image. L Let be the parameter matrix.

2. The method according to claim 1, characterized in that, The calculation of the temperature and brightness of the target under varying ambient temperatures based on the calibration coefficient includes: The temperature and brightness of the target under varying ambient temperatures are calculated using the following formula based on the calibration coefficients. in, h The response data, a The first calibration coefficient, b This is the second calibration coefficient. c This is the third calibration coefficient. i The x-coordinate of the pixel in the image. j represents the ordinate of the pixel in the image. L ( TT () represents the brightness of the target to be measured. TT The temperature of the target to be measured. L ( TB ( ) represents ambient light. TB The ambient temperature.

3. An infrared measuring device for varying ambient temperature, characterized in that, The method for implementing any one of claims 1-2 includes a constant temperature chamber, a blackbody, an infrared measurement system, and a data acquisition computer; The constant temperature chamber is used to provide a constant temperature. The blackbody is placed in the constant temperature chamber to release radiation; The infrared measurement system is used to collect temperature and response data of the blackbody and the constant temperature chamber; The acquisition computer is used to receive the temperature and response data from the infrared measurement system.

4. The apparatus according to claim 3, characterized in that, A temperature sensor is installed on the lens of the infrared measurement system, and the temperature sensor is used to measure the ambient temperature.

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