CN114543998A - Temperature field spatiotemporal distribution measurement device based on staring snapshot spectral imaging - Google Patents

Abstract

The invention belongs to the technical field of temperature field spatiotemporal distribution measuring devices, and in particular relates to a temperature field spatiotemporal distribution measuring device based on staring-type snapshot spectral imaging, comprising an optical imaging collection unit, a spectral imaging unit, a signal sampling unit and a computer PC terminal. The optical imaging collection unit is provided with a spectral imaging unit in the direction of the optical path, the spectral imaging unit is electrically connected with a signal sampling unit, and the signal sampling unit is electrically connected with a computer PC terminal. The invention adopts the spectral imaging technology to achieve, the spectral imaging can simultaneously obtain the image information and spectral information of the target to be measured, the image information can realize the spatial distribution measurement of the temperature field, and the spectral information can realize the accurate temperature measurement of each pixel corresponding to the target.

Description

Temperature field spatiotemporal distribution measurement device based on staring snapshot spectral imaging

technical field

The invention belongs to the technical field of temperature field spatiotemporal distribution measuring devices, and in particular relates to a temperature field spatiotemporal distribution measuring device based on staring-type snapshot spectral imaging.

Background technique

The temperature field measurement can not only obtain fuel combustion, explosion information and performance evaluation, but also obtain the health status and stealth performance evaluation of aviation and aerospace engines, which plays a very important role in the fields of people's livelihood security and national defense equipment. However, the measurement of temperature, especially the measurement of time distribution and spatial distribution of temperature field, has always been an unsolved technical problem. At present, temperature measurement methods can be roughly divided into two categories: contact and non-contact. Contact temperature measurement uses sensors such as thermocouples to make good contact with the measured object, and uses temperature-induced changes in the properties of temperature-sensitive materials to achieve temperature measurement. The addition of sensors hardly changes the temperature of the object, but the measured temperature is required not to exceed the sensor can withstand The upper limit of temperature, the upper limit of thermocouple temperature measurement generally does not exceed 2000 ℃, in addition, contact temperature measurement usually limits the temperature measurement in harsh environments such as corrosion and shock. Non-contact infrared temperature measurement, colorimetric temperature measurement and multi-spectral radiation temperature measurement. Infrared temperature measurement adopts the imaging method of thermal imager to realize temperature measurement, which can realize the distribution measurement of temperature field. It is represented by the products of FLIRE Company in the United States. Ultra-high-speed and ultra-high temperature field measurement applications, and infrared temperature measurement requires knowing the spectral emissivity of the measured object, and the spectral emissivity of the measured object is not only related to the material of the measured object, but also related to temperature, so in practical applications Infrared temperature measurement has limited accuracy. Colorimetric thermometry measures the spectral radiation of two wavelengths to achieve temperature measurement. Using the relationship that the emissivity of adjacent wavelengths of the measured object is approximately equal, the influence of the emissivity is eliminated through the ratio of the radiation energy of adjacent wavelengths, and the realization is achieved within a certain temperature range. A higher accuracy temperature measurement can be achieved, but this technique is not suitable for large dynamic range temperature measurement.

Multi-spectral temperature measurement can realize multiple spectral radiation measurements at the same time. According to the measured spectral information combined with Planck's radiation law, the simultaneous measurement of the temperature of the target to be measured and the spectral emissivity can be achieved. It has the advantages of accurate temperature measurement and wide dynamic range of temperature measurement. The most competitive temperature measurement method in the non-contact temperature measurement method. However, the current multispectral measurement technology mostly adopts grating spectrometer and Fourier transform spectrometer, which not only has limited measurement speed, but also cannot realize imaging measurement. Therefore, the application of multispectral thermometry in the measurement of temperature field distribution is limited.

SUMMARY OF THE INVENTION

In view of the above technical problems, the present invention provides a temperature field spatiotemporal distribution measurement device based on staring snapshot spectral imaging with accurate measurement, wide application range and high safety.

In order to solve the above-mentioned technical problems, the technical scheme adopted in the present invention is:

A temperature field spatiotemporal distribution measurement device based on staring snapshot spectral imaging includes an optical imaging collection unit, a spectral imaging unit, a signal sampling unit and a computer PC terminal. The optical imaging collection unit is provided with a spectral imaging unit in the direction of the optical path. The spectral imaging unit is electrically connected with a signal sampling unit, and the signal sampling unit is electrically connected with a computer PC terminal.

The spectral imaging unit includes a spectral imaging coding module and a detector array, and the detector array is arranged in the optical path direction of the spectral imaging coding module.

The light imaging collection unit adopts a reflective telescope structure, a Cassegrain telescope or a Newtonian telescope.

The spectral imaging coding module adopts a silicon-based flat photonic crystal, and the silicon-based flat photonic crystal performs pseudo-random transmittance coding modulation of the target radiation spectrum through a cross hole, a circular hole or a triangular hole flat photonic crystal air hole.

The detector array adopts a CMOS detector array, the wavelength range of the detector array is 400-900 nm, the pixel size of the detector array is 5.6 μm, and the pixels of the detector array are not less than 2048×1024, The frame rate of the detector array is not lower than 100fps.

The spectral resolution of the spectral imaging unit is greater than 5 nm, the number of spectral channels of the spectral imaging unit is N≧100, the number of actual compression measurements of the spectral imaging unit M≦25, and the compression ratio of the spectral imaging unit is N:M ≥4:1, each spectral measurement pixel of the spectral imaging unit is prepared with a 5×5 silicon-based flat photonic crystal.

A measurement method of a temperature field spatiotemporal distribution measurement device based on staring-type snapshot spectral imaging, comprising the following steps:

S1, the radiation light of the target to be measured is converged and imaged on the spectral imaging unit through the optical imaging collection unit;

S2. The spectral imaging unit converts the optical signal into an electrical signal, and the detector array performs pseudo-random imaging detection on the imaging optical signal encoded by the pseudo-random transmittance of the spectral imaging encoding module;

S3. The electrical signal is collected and transmitted to the computer PC through the signal sampling unit;

S4. Complete the spectral data and image data processing in the computer PC terminal, and then further invert to obtain the spatial distribution and time distribution information of the temperature field.

The compressed measurement signal obtained by the spectral imaging unit is restored on the computer PC to obtain the spectral signal of the target to be measured. According to the spectral signal obtained on each spectral measurement pixel, combined with Planck's radiation law, no less than 100 and The correlation equation between spectral emissivity and temperature, and the linear least squares method is used to linearly fit the measured data to obtain the spectral emissivity and temperature of the target to be measured.

The temperature obtained by each of the spectral measurement pixels is two-dimensionally arranged according to the position of the spectral measurement pixels to obtain the spatial distribution measurement of the temperature field, and the temperature field obtained at each moment is restored in the time dimension to grasp the temperature change rule of the target to be measured. , to obtain a time distribution measurement of the temperature field.

The method for sequentially obtaining no less than 100 equations related to spectral emissivity and temperature is: when the light intensity V _(λ) of the target to be measured is detected by the detector array, the transmittance control matrix of the spectral imaging coding module The Q _i(λ) is regulated, and the i-th regulation spectral signal is detected by the detector array, which constitutes the compressed measurement signal _si as

s _i =∫V _(λ) Q _i(λ) η _(λ) dλ i=1,2,…,M

The η _(λ) represents the spectral response conversion coefficient of the detector, and the η _(λ) is determined by the quantum efficiency of the detector array and the integral coefficient of the peripheral circuit of the detector array, obtained by performing wavelength radiation calibration on the detector array;

满足

多次压缩测量信号S_i满足S_i∈R^M×1，所述

所述

代表透过率调控压缩测量矩阵；The compressed measurement signal _si realized by the spectral imaging unit is sampled as a discrete digital quantity Si by the signal sampling unit, the light intensity signal of the target to be measured is discretely _represented by an N-dimensional vector, and the number of corresponding spectral channels is set to N, and

Satisfy

The multiple compression measurement signal S _i satisfies S _i ∈ R ^M×1 , the

said

represents the transmittance regulation compression measurement matrix;

改写为S＝QV＝QΨα＝Aα，所述A＝QΨ代表传感矩阵，是由压缩测量矩阵Q和稀疏矩阵Ψ共同决定的；然后对S＝QV＝QΨα＝Aα的逆问题进行求解：The spectral signal is sparsely represented as I=Ψα, the α is the K-sparse vector after the spectral signal is sparsed, the K-sparse vector contains K non-zero elements, and the K<<N; the Ψ is a sparse matrix; According to the theoretical framework of compressed sensing, the

Rewritten as S=QV=QΨα=Aα, the A=QΨ represents the sensing matrix, which is jointly determined by the compressed measurement matrix Q and the sparse matrix Ψ; then the inverse problem of S=QV=QΨα=Aα is solved:

然后将待测光谱信号从稀疏信号中正确地恢复出来

依据每个光谱测量像元上获得的光谱信号基于普朗克辐射定律进行温度反演，根据普朗克辐射定律，绝对温度T的光谱辐射温度的公式为：By finding the optimal spectrally sparse signal

Then correctly recover the spectral signal to be measured from the sparse signal

According to the spectral signal obtained on each spectral measurement pixel, the temperature is inverted based on Planck's radiation law. According to Planck's radiation law, the formula for the spectral radiation temperature of the absolute temperature T is:

The L(λ, T) is the radiance of the object, the λ is the wavelength, and the T is the absolute temperature; the ε(λ, T) is the spectral emissivity of the object; the C ₁ =3.7415×10 ⁸ W·μm ⁴ ·m ⁻² ; the C ₂ =1.43879×10 ⁴ μm ⁴ ·K;

When C ₂ /λT>>1 in the short waveband, the Wien formula is used to approximate the Planck formula:

The spectral radiation intensity output signal of the i-th channel of the detector array is:

V _i =τ(λ _i )S(λ _i )L(λ _i ,T), the τ(λ _i ) is the spectral transmittance, and S(λ _i ) is the detector sensitivity;

Then the output signal of the i-th channel is expressed as:

The output signal of the ith channel in the short band is expressed as:

The solution of the target true temperature needs to construct the relationship between the radiance temperature T _i and the target absolute temperature T, which is expressed by the formula:

A 100-wavelength spectral emissivity model is established, expressed as: ε(λ, T)=exp(α ₀ +α ₁ λ+α ₂ λ ² +...+α _m λ ^m ), the α ₀ ,α ₁ ,α ₂ ,…,α _m is a constant, a total of 100 equations are obtained at this time, and the linear least squares method is used to linearly fit the measured data to obtain the spectral emissivity and temperature of the target to be measured.

Compared with the prior art, the present invention has the following beneficial effects:

1. The present invention is realized by using spectral imaging technology. Spectral imaging can simultaneously obtain image information and spectral information of the target to be measured, the image information can realize the measurement of the spatial distribution of the temperature field, and the spectral information can realize the accurate measurement of the temperature of each pixel corresponding to the target.

2. The present invention adopts the multi-spectral radiation temperature measurement method to realize temperature measurement, which can realize the spectral emissivity and temperature measurement of the target to be measured at the same time, and does not need to know the spectral emissivity, the temperature measurement is accurate, and the acquisition of a wide range of spectral information can achieve a relatively wide range of spectral information acquisition. Large dynamic range temperature measurement.

3. The present invention adopts the staring snapshot type spectral imaging method, the spectral image information acquisition speed is fast, the real-time continuous temperature measurement of the target to be measured can be realized, and the time-varying law of each temperature field can be obtained on the basis of the measurement of the spatial distribution of the temperature field.

4. The present invention adopts staring-type snapshot spectral imaging to realize temperature distribution measurement, which is a non-contact spectral imaging measurement method. The present invention uses a telephoto imaging lens to image the temperature field on the spectral imaging acquisition module, which is a non-contact telemetry method. It can avoid harsh environmental influences such as explosion, combustion field impact, corrosion, vibration and so on.

Description of drawings

In order to illustrate the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that are required to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only exemplary, and for those of ordinary skill in the art, other implementation drawings can also be derived from the provided drawings without any creative effort.

The structures, proportions, sizes, etc. shown in this specification are only used to cooperate with the contents disclosed in the specification, so as to be understood and read by those who are familiar with the technology, and are not used to limit the conditions for the implementation of the present invention, so there is no technical The substantive meaning, any modification of the structure, the change of the proportional relationship or the adjustment of the size, without affecting the effect that the present invention can produce and the purpose that can be achieved, should still fall within the technical content disclosed in the present invention. within the scope of coverage.

Fig. 1 is the structural representation of the present invention;

FIG. 2 is a schematic diagram of the spectral imaging unit of the present invention.

Among them: 1 is an optical imaging collection unit, 2 is a spectral imaging unit, 3 is a signal sampling unit, 4 is a computer PC terminal, 2-1 is a spectral imaging coding module, and 2-2 is a detector array.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, not All embodiments, these descriptions are only to further illustrate the features and advantages of the present invention, rather than to limit the claims of the present invention; based on the embodiments in this application, those of ordinary skill in the art can obtain without creative work. All other embodiments belong to the scope of protection of the present application.

The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments. The following examples are intended to illustrate the present invention, but not to limit the scope of the present invention.

In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection Connection, or integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood in specific situations.

As shown in FIG. 1 , the radiation light of the target to be measured is collected and imaged on the spectral imaging unit 2 by the optical imaging collection unit 1 . The spectral imaging unit 2 converts the optical signal into an electrical signal, and the electrical signal is collected and transmitted to the computer through the signal sampling unit 3 PC terminal 4, complete data processing in the computer.

In this embodiment, the optical imaging collection unit 1 works in the visible/near-infrared band, and uses a reflective telescope structure to realize non-contact telemetry. The optical imaging collection unit 1 selects a Cassegrain telescope or a Newtonian telescope. The radiant light of the target to be measured is collected and imaged on the spectral imaging unit 2 .

As shown in FIG. 2, a schematic diagram of a spectral imaging unit is shown, and the imaging unit includes a spectral imaging coding module 2-1 and a detector array 2-2. Spectral coding module 2-1 is designed with a silicon-based flat photonic crystal, and uses cross holes, circular holes, triangular holes and other flat photonic crystal air holes to perform pseudo-random transmittance coding modulation of the target radiation spectrum; the detector array 2-2 is selected The CMOS detector array performs pseudo-random imaging detection on the imaging optical signal encoded by the pseudo-random transmittance of the spectral encoding module 2-1.

As shown in FIG. 2, spectral imaging means that the spectral imaging unit 2 provides the target to be measured with two-dimensional spatial information (x, y) and one-dimensional spectral information. The incident light of each imaging unit of the target is incident on the detector array 2-2 through the spectral encoding module 2-1 of the spectral imaging unit 2 in the entire spectral range. When the light intensity V _(λ) of the target to be measured is detected by the detector, it is regulated by the transmittance regulation matrix Q _i(λ) of the coding plate, and the i-th regulation spectral signal is detected by the detector, which constitutes a compression The measurement signal _si can be described as

s _i =∫V _(λ) Q _i(λ) η _(λ) dλ i=1,2,…,M

Among them, η _(λ) represents the spectral response conversion coefficient of the detector, which is mainly determined by the quantum efficiency of the detector and the integral coefficient of the peripheral circuit of the detector, which is usually obtained by calibrating the wavelength radiation of the detector.

满足

多次压缩测量光谱信号S_i满足S_i∈R^M×1。运用这些矩阵，测量过程可以描述为：The compressed measurement signal realized by the spectral imaging unit 2 is sampled by the signal sampling unit 3 as a discrete digital quantity S _i . The light intensity signal of the target to be measured is discretely represented by an N-dimensional vector, and the number of corresponding spectral channels is set to N, and

Satisfy

The multiple-compression measurement spectral signal _Si satisfies Si _∈ R ^M×1 . Using these matrices, the measurement process can be described as:

代表透过率调控压缩测量矩阵。本实施实例中，探测器阵列2-2选用CMOS探测器阵列有效工作波长选择工作在400-900nm，像元尺寸为5.6μm，像素不小于2048×1024，帧频不低于100fps。整个光谱成像单元2光谱分辨率优于5nm，光谱通道数N设置为N≥100，压缩比N:M≥4:1，其中光谱编码模块2-1每个光谱测量像元采用5×5的硅基平板光子晶体制备。光谱信号稀疏表示为I＝Ψα，其中α为光谱信号稀疏后的K-稀疏向量(包含K个非零元素，其中K<<N)，Ψ是稀疏矩阵。根据压缩感知的理论框架，上式可以改写为

Represents the transmittance modulation compression measurement matrix. In this embodiment, the detector array 2-2 selects a CMOS detector array with an effective working wavelength of 400-900 nm, a pixel size of 5.6 μm, a pixel size of not less than 2048×1024, and a frame rate of not less than 100fps. The spectral resolution of the entire spectral imaging unit 2 is better than 5 nm, the number of spectral channels N is set to N≥100, and the compression ratio is N:M≥4:1. Each spectral measurement pixel of the spectral coding module 2-1 uses a 5×5 Preparation of silicon-based flat-plate photonic crystals. The spectral signal is sparsely expressed as I=Ψα, where α is a K-sparse vector (containing K non-zero elements, where K<<N) after the spectral signal is sparsed, and Ψ is a sparse matrix. According to the theoretical framework of compressed sensing, the above formula can be rewritten as

S=QV=QΨα=Aα

In the above formula, A=QΨ represents the sensing matrix, which is jointly determined by the compressed measurement matrix Q and the sparse matrix Ψ. Then solve the inverse problem of the above equation.

然后将待测光谱信号从稀疏信号中正确地恢复出来

By finding the optimal spectrally sparse signal

Then correctly recover the spectral signal to be measured from the sparse signal

According to the spectral signal obtained on each spectral measurement pixel, temperature inversion is performed based on Planck's radiation law. Planck's law describes the distribution of the radiance of an object at different temperatures as a function of wavelength.

According to Planck's law of radiation, the spectral radiation temperature of the absolute temperature T can be expressed by the formula:

where L(λ,T) is the radiance of the object (W·m ^-2 ·μm ^-1 sr ^-1 ), λ is the wavelength (μm), T is the absolute temperature (K); ε(λ,T) is Spectral emissivity of the object; C ₁ =3.7415×10 ⁸ W·μm ⁴ ·m ⁻² ; C ₂ =1.43879×10 ⁴ μm ⁴ ·K.

When C ₂ /λT>>1 in the short waveband, the Wien formula can be used to approximate the Planck formula.

In this embodiment, the detector array 2-2 selects a CMOS detector array with an effective working wavelength of 400-900 nm, the spectral resolution of the entire spectral imaging unit 2 is better than 5 nm, and the number of spectral channels N is set to N≥100. The spectral radiation intensity output signal of the i-th channel is:

V _i =τ(λ _i )S(λ _i )L(λ _i ,T)

where τ(λ _i ) is the spectral transmittance and S(λ _i ) is the detector sensitivity

Then the output signal of the i-th channel is expressed as:

In the short band it is expressed as:

The solution of the target true temperature needs to construct the relationship between the brightness temperature T _i and the target absolute temperature T,

It is represented by the formula as:

A 100-wavelength spectral emissivity model is established, expressed as: ε(λ, T)=exp(α ₀ +α ₁ λ+α ₂ λ ² +…+α _m λ ^m ), where α ₀ ,α ₁ ,α ₂ ,…,α _m is a constant

At this time, a total of 100 equations can be obtained, and the measured data can be linearly fitted and calculated by the linear least squares method to obtain the spectral emissivity and temperature of the target to be measured. The temperature obtained by each spectral pixel is arranged two-dimensionally according to the position of the imaging pixel to complete the measurement of the spatial distribution of the temperature field, and the temperature change law of the target to be measured can be grasped by restoring the temperature field obtained at each moment in the time dimension. , to obtain a time distribution measurement of the temperature field.

Only the preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the above-mentioned embodiments, and within the scope of knowledge possessed by those of ordinary skill in the art, various aspects can also be made without departing from the purpose of the present invention. Various changes should be included within the protection scope of the present invention.

Claims (10)

1. A temperature field spatiotemporal distribution measurement device based on staring-type snapshot spectral imaging, characterized in that: comprising a light imaging collection unit (1), a spectral imaging unit (2), a signal sampling unit (3) and a computer PC terminal (4) , a spectral imaging unit (2) is provided in the optical path direction of the optical imaging collection unit (1), the spectral imaging unit (2) is electrically connected with a signal sampling unit (3), and the signal sampling unit (3) A computer PC terminal (4) is electrically connected. 2. A temperature field spatiotemporal distribution measuring device based on staring snapshot type spectral imaging according to claim 1, wherein the spectral imaging unit (2) comprises a spectral imaging coding module (2-1) and a detection A detector array (2-2), the detector array (2-2) is arranged in the optical path direction of the spectral imaging encoding module (2-1). 3. a kind of temperature field spatiotemporal distribution measuring device based on staring snapshot type spectral imaging according to claim 1, is characterized in that: described light imaging collection unit (1) adopts reflective telescope structure, Cassegrain telescope or Newtonian telescope. 4. A temperature field spatiotemporal distribution measuring device based on staring snapshot type spectral imaging according to claim 2, wherein the spectral imaging coding module (2-1) adopts a silicon-based flat plate photonic crystal, and the The silicon-based flat photonic crystal performs pseudo-random transmittance coding modulation of the target radiation spectrum through the cross hole, the circular hole or the triangular hole flat photonic crystal air hole. 5 . The temperature field spatiotemporal distribution measurement device based on staring-type snapshot spectral imaging according to claim 2 , wherein the detector array ( 2 - 2 ) adopts a CMOS detector array, and the detector The wavelength range of the array (2-2) is 400-900 nm, the pixel size of the detector array (2-2) is 5.6 μm, and the pixels of the detector array (2-2) are not less than 2048×1024, The frame rate of the detector array (2-2) is not lower than 100fps. 6. A temperature field spatiotemporal distribution measuring device based on staring-type snapshot spectral imaging according to claim 1, characterized in that: the spectral imaging unit (2) has a spectral resolution greater than 5 nm, and the spectral imaging unit ( 2) The number of spectral channels is N≥100, the actual compression measurement times M≤25 of the spectral imaging unit (2), the compression ratio of the spectral imaging unit (2) is N:M≥4:1, the spectral imaging unit (2) Each spectral measurement pixel of the imaging unit (2) is prepared by using a 5×5 silicon-based flat plate photonic crystal. 7. The measurement method of a temperature field spatiotemporal distribution measuring device based on staring type snapshot spectral imaging according to any one of claims 1-6, characterized in that: comprising the following steps: S1, the radiation light of the target to be measured is collected and imaged on the spectral imaging unit (2) through the optical imaging collection unit (1); S2. The spectral imaging unit (2) converts the optical signal into an electrical signal, and the detector array (2-2) performs pseudo-random imaging detection on the imaging optical signal encoded by the pseudo-random transmittance of the spectral imaging encoding module (2-1) ; S3, the electrical signal is collected and transmitted to the computer PC terminal (4) through the signal sampling unit (3); S4. Complete the spectral data and image data processing in the computer PC terminal (4), and then further invert to obtain the spatial distribution and time distribution information of the temperature field. 8. The measurement method of a temperature field spatiotemporal distribution measuring device based on staring-type snapshot spectral imaging according to claim 7, characterized in that: the compressed measurement signal obtained by the spectral imaging unit (2) is at a computer PC end (4) Restoring and obtaining the spectral signal of the target to be measured, according to the spectral signal obtained on each spectral measurement pixel, combined with Planck's radiation law, sequentially obtain no less than 100 equations related to spectral emissivity and temperature, using the linear minimum The square method performs linear fitting calculation on the measured data to obtain the spectral emissivity and temperature of the target to be measured. 9 . The method for measuring a temperature field spatiotemporal distribution measuring device based on staring-type snapshot spectral imaging according to claim 8 , wherein the temperature obtained by each of the spectral measurement pixels is measured by the spectral measurement pixel. 10 . The position is arranged in two dimensions to obtain the spatial distribution measurement of the temperature field, and the temperature field obtained at each moment is restored in the time dimension to grasp the temperature change law of the target to be measured, and obtain the time distribution measurement of the temperature field. 10. The method for measuring a temperature field spatiotemporal distribution measuring device based on staring-type snapshot spectral imaging according to claim 9, characterized in that: the sequential acquisition of no less than 100 equations related to spectral emissivity and temperature The method is as follows: when the light intensity V _(λ) of the target to be measured is detected by the detector array (2-2), it is adjusted by the transmittance control matrix Q _i(λ) of the spectral imaging coding module (2-1). regulation, the i-th regulation spectral signal is detected by the detector array (2-2), forming a compressed measurement signal _si as s _i =∫V _(λ) Q _i(λ) η _(λ) dλ i=1,2,…,M The η _(λ) represents the spectral response conversion coefficient of the detector, and the η _(λ) is determined by the quantum efficiency of the detector array (2-2) and the integral coefficient of the peripheral circuit of the detector array (2-2). obtained by performing wavelength radiation calibration on the device array (2-2); The compressed measurement signal _si realized by the spectral imaging unit (2) is sampled as a discrete digital quantity Si by the signal sampling unit (3 ₎ , the light intensity signal of the target to be measured is discretely represented by an N-dimensional vector, and the number of corresponding spectral channels is set as: N, and

Satisfy

The multiple compression measurement signal S _i satisfies S _i ∈ R ^M×1 , the

said

represents the transmittance regulation compression measurement matrix; The spectral signal is sparsely represented as I=Ψα, the α is the K-sparse vector after the spectral signal is sparsed, the K-sparse vector contains K non-zero elements, and the K<<N; the Ψ is a sparse matrix; According to the theoretical framework of compressed sensing, the

Rewritten as S=QV=QΨα=Aα, the A=QΨ represents the sensing matrix, which is jointly determined by the compressed measurement matrix Q and the sparse matrix Ψ; then the inverse problem of S=QV=QΨα=Aα is solved:

By finding the optimal spectrally sparse signal

Then correctly recover the spectral signal to be measured from the sparse signal

According to the spectral signal obtained on each spectral measurement pixel, the temperature is inverted based on Planck's radiation law. According to Planck's radiation law, the formula for the spectral radiation temperature of the absolute temperature T is:

The L(λ, T) is the radiance of the object, the λ is the wavelength, and the T is the absolute temperature; the ε(λ, T) is the spectral emissivity of the object; the C ₁ =3.7415×10 ⁸ W·μm ⁴ ·m ⁻² ; the C ₂ =1.43879×10 ⁴ μm ⁴ ·K; When C ₂ /λT>>1 in the short waveband, the Wien formula is used to approximate the Planck formula:

The spectral radiation intensity output signal of the i-th channel of the detector array (2-2) is: V _i =τ(λ _i )S(λ _i )L(λ _i ,T), the τ(λ _i ) is the spectral transmittance, and S(λ _i ) is the detector sensitivity; Then the output signal of the i-th channel is expressed as:

The output signal of the ith channel in the short band is expressed as:

The solution of the target true temperature needs to construct the relationship between the radiance temperature T _i and the target absolute temperature T, which is expressed by the formula:

A 100-wavelength spectral emissivity model is established, expressed as: ε(λ, T)=exp(α ₀ +α ₁ λ+α ₂ λ ² +...+α _m λ ^m ), the α ₀ ,α ₁ ,α ₂ ,…,α _m is a constant, a total of 100 equations are obtained at this time, and the linear least squares method is used to linearly fit the measured data to obtain the spectral emissivity and temperature of the target to be measured.

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