Spectral imaging device radiation calibration method and system

Abstract

The application discloses a kind of spectral imaging device radiation calibration method and system, the radiation response model of the pixel of spectral imaging device is constructed, target light changes in spectral dimension and radiation dimension, obtains the spectral radiance data of target light and the response data of the pixel of spectral imaging device under different spectral or / and target light of radiance, according to spectral radiance data, the equivalent radiance value that pixel receives multiple waveband light is obtained, and then according to the equivalent radiance value that pixel receives multiple waveband light and the response data of pixel, radiation response coefficient value is obtained, the radiation response model that the response value of pixel is described with the radiance relationship of the pixel received multiple waveband light is obtained, the radiation calibration of the spectral imaging device that the present application realizes to the coupling of spectral information and spatial information.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of spectral imaging, in particular to a spectral imaging device radiation calibration method and system. BACKGROUND

[0002] Spectral imaging technology can simultaneously obtain the geometry and spectral information of a target. Spectral imaging devices can be divided into interference type, dispersion type and filter type according to the principle of light splitting. The interference type obtains the interference pattern of a target and obtains the spectral information through Fourier transform. The dispersion type uses a prism or a grating for light splitting. The filter type places a filter in front of a detector for light splitting. As a quantitative remote sensing method, the radiation measurement accuracy of spectral imaging technology is crucial, and radiation calibration is the key to ensuring the accuracy of radiation measurement.

[0003] The existing radiation calibration method establishes a one-dimensional linear equation of the radiation response and the signal of each wave band. By changing the brightness of a certain specific light source, an array of spectral imaging device response values changing with the brightness of the light source is obtained, and then the radiation response model is obtained through fitting or other methods. However, for a spatial-spectral coupling type spectral imaging device, the response of each pixel is the result of superposition of multi-band signals, and the spectral information and spatial information are coupled together, so the existing radiation calibration method is not applicable. SUMMARY

[0004] The purpose of the present application is to provide a spectral imaging device radiation calibration method and system, which can realize the radiation calibration of a spectral imaging device coupling spectral information and spatial information.

[0005] To achieve the above purpose, the present application provides the following technical scheme:

[0006] A spectral imaging device radiation calibration method, the spectral imaging device is used for obtaining target light and separating the target light into multiple wave band lights, and a pixel of the spectral imaging device is used for responding to the multiple wave band lights;

[0007] The spectral imaging device radiation calibration method comprises:

[0008] Constructing a radiation response model of the pixel of the spectral imaging device, the radiation response model of the pixel describes the relationship between the response value of the pixel and the radiance of the multiple wave band lights received by the pixel, and the radiation response model comprises a radiation response coefficient;

[0009] Controlling the target light to change in the spectral dimension and the radiance dimension, measuring the spectral radiance of the target light and making the spectral imaging device obtain the target light to obtain the response value of the pixel under the target light with different spectrum or / and radiance, and obtaining multiple sets of spectral radiance data of the target light and response data of the pixel.

[0010] For any set of spectral radiance data, obtain the radiance value of any one of the multiple wavelengths of light in the target light corresponding to this set based on the spectral radiance data of this set.

[0011] The energy contribution ratio of the multiple wavelengths of light causing the pixel to respond is obtained according to the first spectral response function of the pixel. For any set of spectral radiance data, the equivalent radiance value of the multiple wavelengths of light received by the pixel in the target light corresponding to the set is obtained according to the energy contribution ratio of the pixel corresponding to the multiple wavelengths of light and the radiance value of the multiple wavelengths of light in the target light corresponding to the set. The first spectral response function of the pixel describes the response capability of the pixel to light of different wavelengths when light enters the spectral imaging device.

[0012] Based on the equivalent radiance values ​​of the various wavelengths of light received by the pixels from the target light and the response data of the corresponding pixels in each group, a radiation response coefficient value is obtained, and the radiation response model corresponding to the radiation response coefficient value is obtained.

[0013] Optionally, controlling the target light in both the spectral and radiative dimensions includes:

[0014] The target light is formed by mixing the emitted light from multiple light sources, which have different emission spectra. The energy ratio of the emitted light from the multiple light sources is controlled to change, so that the target light varies in the spectral and radiative dimensions.

[0015] Optionally, the target light is formed by mixing the emitted light from the first light source and the second light source, wherein the emission spectra of the first light source and the second light source are different;

[0016] Controlling the target light to vary in the spectral and radiative dimensions, measuring the spectral radiance of the target light under different target light states, and enabling the spectral imaging device to acquire the target light to obtain the response value of the pixel include:

[0017] The emitted light brightness of the first light source is changed successively with a first preset step size, so that the emitted light brightness of the first light source changes successively. At each brightness level of the first light source, the emitted light brightness of the second light source is changed successively with a second preset step size, so that the emitted light brightness of the second light source changes successively. At each brightness level of the second light source, the spectral radiance of the target light is measured and the response value of the pixel of the spectral imaging device is obtained.

[0018] Optionally, obtaining the energy contribution ratio of the multiple wavelength bands of light causing the pixel to respond based on the first spectral response function of the pixel includes:

[0019] For any one of the plurality of waveband lights, integrating the first spectral response function over the wavelength within the waveband range of the waveband light to obtain a first integral value, and integrating the first spectral response function over the wavelength within the waveband range of the plurality of waveband lights to obtain a second integral value, and obtaining the proportion of energy contribution of the waveband light to the pixel according to the ratio of the first integral value to the second integral value.

[0020] Optionally, obtaining the proportion of energy contribution of the plurality of waveband lights to the pixel according to the first spectral response function of the pixel includes:

[0021] obtaining the proportion of energy contribution of any one of the plurality of waveband lights to the pixel according to the first spectral response function of the pixel;

[0022] For any one of the plurality of waveband lights, integrating the first spectral response function over the wavelength within the waveband range of the waveband light to obtain a first integral value, and integrating the first spectral response function over the wavelength within the waveband range of the plurality of waveband lights to obtain a second integral value, and obtaining the proportion of energy contribution of the waveband light to the pixel according to the ratio of the first integral value to the second integral value.

[0023] For any one of the plurality of waveband lights, obtaining the proportion of energy contribution of the waveband light to the pixel according to the first spectral response function of the pixel, and obtaining the radiance value of the waveband light in the target light corresponding to the group according to the radiance value of the waveband light in the target light corresponding to the group.

[0024] obtaining the proportion of energy contribution of any one of the plurality of waveband lights to the pixel according to the first spectral response function of the pixel;

[0025] Optionally, obtaining the proportion of energy contribution of the plurality of waveband lights to the pixel according to the first spectral response function of the pixel includes:

[0026] obtaining the proportion of energy contribution of any one of the plurality of waveband lights to the pixel according to the first spectral response function of the pixel;

[0027] For each of the plurality of waveband lights, according to the total coefficient value and the energy contribution ratio of the current waveband light, a radiometric response coefficient value corresponding to the current waveband light is obtained, the radiometric response coefficient value corresponding to the current waveband light representing a relationship between a response value of the pixel and an apparent luminance of the current waveband light received by the pixel;

[0028] According to the radiometric response coefficient values corresponding to the plurality of waveband lights, the radiometric response model of the pixel is obtained.

[0029] Optionally, according to the equivalent apparent luminance values of the plurality of waveband lights in the target light received by the pixel and the response data of the pixel corresponding to each group, a radiometric response coefficient value is obtained, and obtaining the radiometric response model corresponding to the radiometric response coefficient value comprises:

[0030] According to the equivalent apparent luminance values of the plurality of waveband lights in the target light received by the pixel and the response data of the pixel corresponding to each group, an initial radiometric response model of the pixel is obtained, and a radiometric response coefficient initial value is obtained, the radiometric response coefficient initial value being a radiometric response coefficient value in the initial radiometric response model;

[0031] A target function is established, and iterative operation is performed based on the target function, so that a radiometric response coefficient value satisfying a condition is obtained, so that a radiometric response model of the pixel determined by the radiometric response coefficient value satisfying the condition is obtained, the target function representing that a difference between an actual response value of the pixel and an estimated response value of the pixel is minimized, the estimated response value of the pixel being a predicted response value of the pixel determined according to a current radiometric response coefficient value and the radiometric response model.

[0032] Optionally, the iterative operation based on the target function comprises:

[0033] Derivation of the target function with respect to the radiometric response coefficient is performed to obtain a gradient function of the target function with respect to the radiometric response coefficient;

[0034] In each iteration, the current radiometric response coefficient value is substituted into the gradient function to obtain a gradient value obtained in the current iteration, and the radiometric response coefficient value is further updated along a direction in which a value of the gradient function decreases, so that the next iteration is performed with the updated radiometric response coefficient value;

[0035] The iteration is stopped when an iteration stop condition is met, and a radiometric response coefficient value obtained in the last iteration is the radiometric response coefficient value satisfying the condition.

[0036] Optionally, updating the radiation response coefficient value in a direction in which the value of the gradient function decreases comprises: taking, as the updated radiation response coefficient value, a value obtained by subtracting a preset difference from the current radiation response coefficient value, the preset difference being a product of a learning rate and the gradient value obtained in the current iteration.

[0037] A spectral imaging device radiation calibration system, the spectral imaging device being configured to acquire target light and separate the target light into a plurality of waveband lights, a pixel of the spectral imaging device being configured to generate a response to the plurality of waveband lights;

[0038] The spectral imaging device radiation calibration system comprises:

[0039] A light source device configured to emit the target light;

[0040] A measurement device configured to measure a spectral radiance of the target light;

[0041] A processing device connected to the light source device and the measurement device respectively, and configured to perform the steps of the spectral imaging device radiation calibration method according to any one of the preceding items.

[0042] According to the technical solution, the spectral imaging device radiation calibration method and system provided by the application, the spectral imaging device is configured to acquire target light and separate the target light into a plurality of waveband lights, and a pixel of the spectral imaging device is configured to generate a response to the plurality of waveband lights. The spectral imaging device radiation calibration method comprises the following steps: constructing a radiation response model of the pixel of the spectral imaging device, the radiation response model of the pixel describing a relationship between a response value of the pixel and a radiance of the plurality of waveband lights received by the pixel, and the radiation response model comprising a radiation response coefficient; controlling the target light to vary in a spectral dimension and a radiance dimension, measuring a spectral radiance of the target light and obtaining a response value of the pixel under the target light with different spectra or / and radiance, and obtaining a plurality of sets of spectral radiance data of the target light and response data of the pixel; for any one set of spectral radiance data, obtaining a radiance value of any one waveband light of the plurality of waveband lights in the corresponding target light of the set; obtaining a proportion of energy contribution of the plurality of waveband lights to the response of the pixel according to a first spectral response function of the pixel, and for any one set of spectral radiance data, obtaining an equivalent radiance value of the plurality of waveband lights received by the pixel in the corresponding target light of the set according to the proportion of energy contribution of the plurality of waveband lights to the pixel and according to the radiance value of the plurality of waveband lights in the corresponding target light of the set; further, obtaining the radiation response coefficient value according to the equivalent radiance values of the plurality of waveband lights received by the pixel in the target light and the response data of the pixel of each set, and obtaining the radiation response model corresponding to the radiation response coefficient value.

[0043] The spectral imaging device radiation calibration method and system of the present application change the target light in the spectral dimension and the radiation dimension, obtain the spectral radiance data of the target light and the response data of the pixels of the spectral imaging device under the target light of different spectra or / and radiance, obtain the equivalent radiance value of the pixels receiving the light of multiple wave bands according to the spectral radiance data, and further obtain the radiation response coefficient value of the radiation response model of the pixels according to the equivalent radiance value of the pixels receiving the light of multiple wave bands and the response data of the pixels, and obtain the radiation response model describing the relationship between the response value of the pixels and the radiance of the light of multiple wave bands received by the pixels, so that the radiation calibration of the spectral imaging device coupling the spectral information and the spatial information is realized. BRIEF DESCRIPTION OF DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0045] Figure 1 A flow chart of a spectral imaging device radiation calibration method provided by an embodiment of the present application;

[0046] Figure 2 A method flow chart of controlling the target light to change in the spectral dimension and the radiation dimension in a spectral imaging device radiation calibration method provided by an embodiment of the present application;

[0047] Figure 3 A schematic diagram of a spectral imaging device radiation calibration system provided by an embodiment of the present application;

[0048] Figure 4 The emission spectrum of a halogen lamp under two different brightnesses in an embodiment of the present application;

[0049] Figure 5 The emission spectrum of a plasma lamp under two different brightnesses in an embodiment of the present application;

[0050] Figure 6 The emission spectrum of a halogen lamp and a plasma lamp under four different brightness combinations in an embodiment of the present application;

[0051] Figure 7-1 The spectral response function curve of the R pixel of a spectral imaging device in an embodiment of the present application;

[0052] Figure 7-2 The spectral response function curve of the G pixel of a spectral imaging device in an embodiment of the present application;

[0053] Figure 7-3 Spectral response function curve of B pixel of spectral imaging device of an embodiment of the present application;

[0054] Figure 7-4 Spectral response function curve of NIR pixel of spectral imaging device of an embodiment of the present application;

[0055] Figure 8 Schematic diagram of spectral imaging device provided by an embodiment of the present application;

[0056] Figure 9 Optical lens transmittance curve diagram of spectral imaging device provided by an embodiment of the present application;

[0057] Figure 10 Filter element transmittance curve diagram of spectral imaging device provided by an embodiment of the present application;

[0058] Figure 11 Detector quantum efficiency curve diagram of spectral imaging device provided by an embodiment of the present application;

[0059] Figure 12 Flow chart of spectral imaging device radiation calibration method provided by another embodiment of the present application.

[0060] The reference signs in the attached drawings of the specification include:

[0061] 100-integrating sphere, 101-light source, 102-measuring device, 103-spectral imaging device, 104-processing device, 200-target light, 201-optical lens, 202-filter element, 203-detector. DETAILED DESCRIPTION

[0062] In order to make the personnel in the technical field better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the personnel of ordinary skill in the art without making creative efforts should belong to the scope of protection of the present application.

[0063] The present embodiment provides a spectral imaging device radiation calibration method, the spectral imaging device is used for acquiring target light and separating the target light into multiple waveband lights, and the pixels of the spectral imaging device are used for responding to the multiple waveband lights.

[0064] Reference can be made to Figure 1 , Figure 1A flow chart of a method for radiometric calibration of a spectral imaging device is provided for an embodiment, the method comprising the steps of:

[0065] S11: constructing a radiation response model of a pixel of the spectral imaging device, the radiation response model of the pixel describing a relationship between a response value of the pixel and an irradiance of the plurality of wavebands of light received by the pixel, the radiation response model comprising radiation response coefficients.

[0066] The response generated by a pixel of the spectral imaging device is a result of the superposition of the responses of the pixel to the plurality of wavebands of light, and thus the spectral imaging device is a spectral imaging device that couples spatial information and spectral information. The radiation response model of a pixel describes a relationship between a response value of the pixel and an irradiance of the plurality of wavebands of light received by the pixel.

[0067] S12: controlling the target light to vary in spectral dimension and irradiance dimension, measuring spectral radiance of the target light under different spectra or / and irradiance of the target light, and causing the spectral imaging device to acquire the target light to obtain a response value of the pixel, to obtain a plurality of sets of spectral radiance data of the target light and response data of the pixel.

[0068] The spectral dimension refers to the dimension of spectral variation, and the irradiance dimension refers to the dimension of irradiance variation.

[0069] Measuring the spectral radiance of the target light includes measuring the irradiance of different wavelengths of light in the target light, i.e., the measured spectral radiance data includes irradiance data of different wavelengths of light in the target light.

[0070] The spectral or / and irradiance of the target light is controlled to vary. The spectral radiance of the target light is measured under any spectrum or / and irradiance of the target light to obtain spectral radiance data of the target light under the current state of the target light. The spectral imaging device is caused to acquire the target light under any spectrum or / and irradiance of the target light, the target light is separated into the plurality of wavebands of light, the pixel of the spectral imaging device generates a response to the plurality of wavebands of light, and a response value of the pixel is obtained. Thus, a plurality of sets of spectral radiance data of the target light and response data of the pixel are obtained, and each set of spectral radiance data and response data of the pixel is obtained under any state of the target light.

[0071] S13: for any set of the spectral radiance data, obtaining an irradiance value of any waveband of light of the plurality of wavebands of light in the target light corresponding to the set from the spectral radiance data of the set.

[0072] S14: obtaining, according to the first spectral response function of the pixel, the energy contribution proportion of the multiple waveband lights to the response of the pixel, and obtaining, for any group of the spectral radiance data, the equivalent radiance value of the multiple waveband lights received by the pixel in the corresponding target light of the group according to the energy contribution proportion of the pixel to the multiple waveband lights and the radiance value of the multiple waveband lights in the corresponding target light of the group.

[0073] The first spectral response function of the pixel describes the response capability of the pixel to different wavelengths of light when the light enters the spectral imaging device.

[0074] When the target light enters the spectral imaging device, the target light is separated into multiple waveband lights, and the pixel responds to the multiple waveband lights. The energy contribution proportion of any waveband light to the response of the pixel is related to the response capability of the pixel to the waveband light, and therefore, the energy contribution proportion of any waveband light to the response of the pixel can be obtained according to the first spectral response function of the pixel.

[0075] The radiance of the light received by the pixel, i.e., the radiance of the light that causes the pixel to respond, is related to the radiation transmission process when the light enters the spectral imaging device and is related to the response capability of the pixel to different wavelengths of light when the light enters the spectral imaging device.

[0076] For any group of spectral radiance data, the equivalent radiance value of the multiple waveband lights received by the pixel in the corresponding target light of the group is obtained according to the radiance value of the multiple waveband lights in the corresponding target light of the group and the energy contribution proportion of the pixel to the multiple waveband lights. The equivalent radiance value can also be understood as the radiance value of the multiple waveband lights that causes the pixel to respond under the corresponding target light of the group.

[0077] S15: obtaining, according to the equivalent radiance values of the multiple waveband lights received by the pixel in the target light and the response data of the pixel corresponding to each group, a radiation response coefficient value, and obtaining the radiation response model corresponding to the radiation response coefficient value.

[0078] After the radiation response coefficient value is determined, the radiation response model of the pixel can be obtained.

[0079] The spectral imaging device radiation calibration method of the embodiment realizes the radiation calibration of the spectral imaging device that couples spectral information and spatial information.

[0080] In some embodiments, the control of the target light in the spectral dimension and the radiometric dimension comprises: the target light is formed by mixing the light emitted by a plurality of light sources, the emission spectrum of the plurality of light sources is different, and the energy proportion of the light emitted by the plurality of light sources is controlled to change so that the target light changes in the spectral dimension and the radiometric dimension.

[0081] In the embodiment, the radiation calibration is performed by using a plurality of light sources, the emission spectrum of each light source is different, and the light emitted by each light source is mixed at different energy proportions so that the target light changes in both the spectral dimension and the radiometric dimension, and sufficient target light states can be provided to measure sufficient radiation calibration data. In the embodiment, the type of light source used and the emission spectrum of each light source are not limited, and can be selected according to the radiation calibration requirement in actual application. In some embodiments, a plurality of light sources are arranged in the integrating sphere, the target light is formed by mixing the light emitted by the plurality of light sources, and the target light is output from the integrating sphere. The light emitted by the plurality of light sources is mixed by the integrating sphere to form the target light, which can make the spectrum and brightness of the target light formed by mixing uniform, and help to improve the accuracy of the radiation calibration.

[0082] In some embodiments, the target light is formed by mixing the light emitted by a first light source and a second light source, and the emission spectrum of the first light source and the second light source is different. Accordingly, the control of the target light in the spectral dimension and the radiometric dimension can be performed by the following method: under different target light states, the spectral radiance of the target light is measured, and the target light is acquired by the spectral imaging device to obtain the response value of the pixel, which comprises: the brightness of the light emitted by the first light source is changed by a first preset step by step, the brightness of the light emitted by the first light source is changed by the first preset step by step, under each brightness level of the first light source, the brightness of the light emitted by the second light source is changed by a second preset step by step, the brightness of the light emitted by the second light source is changed by the second preset step by step, and under each brightness level of the second light source, the spectral radiance of the target light is measured, and the response value of the pixel of the spectral imaging device is obtained.

[0083] The brightness of the light emitted by the first light source is changed by a first preset step by step, which can be that the brightness of the light emitted by the first light source is increased or decreased by the first preset step by step. The brightness of the light emitted by the first light source is changed by the first preset step by step. When the first light source is at any brightness level, the brightness of the light emitted by the second light source is changed by a second preset step by step, which can be that the brightness of the light emitted by the second light source is increased or decreased by the second preset step by step. In the embodiment, the first preset step and the second preset step are not limited, and can be set according to the light emission of the light source used and the radiation calibration requirement in actual application.

[0084] For example, refer to Figure 2 , Figure 2A method for controlling the variation of target light in the spectral dimension and the radiation dimension is provided for an embodiment of the spectral imaging device radiation calibration method, and the method flow chart comprises the following processes: simultaneously turning on a first light source and a second light source, first setting the first light source to be the brightest, i.e. the first light source is at the highest brightness level; at this time, the second light source is changed from dark to bright in a second preset step, and the data of the spectral imaging device is acquired when the second light source is at each brightness level, and the spectral radiance data is acquired and saved simultaneously. Then, the brightness of the first light source is reduced by a first preset step, at this time, the second light source is changed from dark to bright in a second preset step, and the data of the spectral imaging device is acquired when the second light source is at each brightness level, and the spectral radiance data is acquired and saved simultaneously. Then, the brightness of the first light source is reduced by a first preset step again, at this time, the second light source is still changed from dark to bright in a second preset step, and the spectral radiance data is acquired and saved simultaneously. This is repeated until the first light source is the dimmest. Finally, all the light sources are turned off, the data of the spectral imaging device under dark background is acquired, and the spectral radiance data is acquired and saved.

[0085] For example, reference can be made to Figure 3 , Figure 3 A schematic diagram of a spectral imaging device radiation calibration system is provided for an embodiment, as shown in the figure, a plurality of light sources 101 are arranged in the integrating sphere 100, and the plurality of light sources 101 include a plurality of light sources emitting different spectra. The target light is output by the integrating sphere 100, the spectral imaging device 103 acquires the target light to obtain the response data of the pixel, and the spectral radiance of the target light is measured by the measuring device 102. The exposure time, gain and other parameters of the spectral imaging device 103 can be set first, the light sources 101 built-in the integrating sphere 100 are preheated for a period of time, and the data acquisition is performed after waiting for the light sources 101 to be stable.

[0086] For example, in a specific example, two light sources, i.e. a first light source and a second light source, are arranged in the integrating sphere 100, the first light source is a halogen lamp, and the second light source is a plasma lamp, and the halogen lamp and the plasma lamp are combined. For example, reference can be made to Figure 4 、 Figure 5 and Figure 6 , Figure 4 The emission spectra of the halogen lamp at two different brightness levels for an embodiment are measured when the halogen lamp is built-in the integrating sphere 100, including the emission spectrum curve at brightness 1 and the emission spectrum curve at brightness 2. Figure 5 The emission spectra of the plasma lamp at two different brightness levels for an embodiment are measured when the plasma lamp is built-in the integrating sphere 100, including the emission spectrum curve at brightness 3 and the emission spectrum curve at brightness 4. Figure 6The emission spectra of the halogen lamp and the plasma lamp in four different combinations of brightness in an embodiment are measured when the halogen lamp and the plasma lamp are placed in the integrating sphere 100, wherein the light source combination 1 is that the halogen lamp is at brightness 1 and the plasma lamp is at brightness 3, the light source combination 2 is that the halogen lamp is at brightness 1 and the plasma lamp is at brightness 4, the light source combination 3 is that the halogen lamp is at brightness 2 and the plasma lamp is at brightness 3, and the light source combination 4 is that the halogen lamp is at brightness 2 and the plasma lamp is at brightness 4. In each of the above spectral diagrams, the abscissa represents the wavelength in nm, and the ordinate represents the radiance in w·m -2 ˙nm -1 ˙sr -1 In order to realize the non-proportional change of the radiance values in different wave bands, different brightness levels are set for the two light sources respectively to combine, so that the radiance values at different central wavelengths can be changed in different proportions.

[0087] In some embodiments, for any set of spectral radiance data, obtaining, according to the spectral radiance data of the set, a radiance value of any one of the multiple wave bands of light in the target light corresponding to the set includes: for any set of the spectral radiance data, for any one of the wave bands, according to the spectral radiance data of the set, summing the radiance data corresponding to each wavelength within the wave band range of the wave band to obtain a sum value, and obtaining, according to a ratio of the sum value to the bandwidth of the wave band, the radiance value of the wave band in the target light corresponding to the set.

[0088] In some embodiments, summing the radiance data corresponding to each wavelength within the wave band range of the wave band according to the spectral radiance data of the set can be integrating the wavelengths within the wave band range of the wave band according to the spectral radiance data of the set, and further, obtaining, according to a ratio of a sum value obtained by the integration to the bandwidth of the wave band, the radiance value of the wave band in the target light. Exemplarily, the measured radiance value of any one of the wave bands in the target light can be calculated according to the following formula:

[0089] ; (1)

[0090] wherein L eq (band i ) represents the radiance value corresponding to the wave band i, [λ1, λ2] represents the wave band range of the wave band i, and L(λ) represents the measured radiance data at the wavelength λ, i.e., the measured radiance data at the wavelength λ.

[0091] In some implementations, obtaining the energy contribution ratio of the multiple wavelength bands of light to the pixel based on the first spectral response function of the pixel includes: for any wavelength band of light, integrating the first spectral response function with respect to wavelength within the wavelength range of the wavelength band of light to obtain a first integral value, and integrating the first spectral response function with respect to wavelength within the wavelength range of the multiple wavelength bands of light to obtain a second integral value, and obtaining the energy contribution ratio of the wavelength band of light to the pixel based on the ratio of the first integral value to the second integral value.

[0092] For example, the energy contribution ratio of any wavelength of light to a pixel can be calculated using the following formula:

[0093] ; (2)

[0094] Where, α ij λ represents the proportion of energy contribution of band i to pixel j. i λ represents the band range of band i. ∑i R represents the wavelength range of the various wavelength bands of light. (j) (λ) represents the first spectral response function of pixel j.

[0095] In some implementations, the energy contribution ratios of the multiple wavelength bands can be normalized. For example, an initial value of the energy contribution ratio of one wavelength band can be used as a reference value, and for any other wavelength band, the ratio of the initial value of the energy contribution ratio of that wavelength band to the reference value can be used as the normalized energy contribution ratio of that wavelength band.

[0096] In one specific example, the spectral imaging device includes R pixels, G pixels, B pixels, and NIR pixels. The spectral imaging device separates incoming light into four wavelength bands with center wavelengths of 450 nm, 555 nm, 660 nm, and 840 nm, respectively. (See reference...) Figures 7-1 to 7-4 , Figure 7-1 This is a spectral response function curve of the R-pixel of a spectral imaging device according to an embodiment. Figure 7-2 This is the spectral response function curve of a G-pixel in a spectral imaging device according to an embodiment. Figure 7-3 This is the spectral response function curve of the B-pixel of a spectral imaging device according to an embodiment. Figure 7-4 This is a spectral response function curve of an NIR pixel in a spectral imaging device according to an embodiment. For any pixel and any spectral band, the energy contribution ratio of that spectral band to the pixel can be obtained by calculating the area ratio enclosed by the curve at that spectral band and the horizontal axis.

[0097] It can be calculated using the following formula:

[0098] ; (3)

[0099] (4)

[0100] wherein, α 4j represents the energy contribution proportion of waveband 4 to pixel j, formula (3) represents the normalized calculation of the energy contribution proportion. Please refer to Table 1 below, which shows the energy contribution proportion values of various wavebands of various pixels obtained by calculation.

[0101] Table 1

[0102]

[0103] In some embodiments, the spectral imaging device comprises an optical lens, a filter element and a detector. Please refer to Figure 8 , Figure 8 Fig. 1 is a schematic diagram of a spectral imaging device according to an embodiment, target light 200 passes through optical lens 201 and filter element 202 in sequence, filter element 202 separates target light 200 into multiple waveband lights, only the light of these specific wavelengths passing through filter element 202 reaches detector 203. The response of each pixel of detector 203 is the result of the superposition of multi-waveband signals, and the images of the object in different wavebands can be obtained by decoupling. This imaging technology has the advantages of low cost, easy miniaturization and multi-waveband simultaneous imaging. Filter element 202 can be a multi-bandpass narrowband filter, and detector 203 can be a color sensor.

[0104] According to the whole-link spectral transmission process, the spectral response function of the whole spectral imaging device is mainly determined by the transmittance of the optical lens, the transmittance of the filter element and the quantum efficiency of the detector. Therefore, the radiation response function of pixel j can be represented as:

[0105] (5)

[0106] wherein, T lens (λ) represents the transmittance function of the optical lens, T filter (λ) represents the transmittance function of the filter element, QE (j) (λ) represents the quantum efficiency function of the detector, and j represents pixel j.

[0107] Exemplarily, taking a single-lens four-waveband spectral imaging device as an example, the data of the four wavebands are shown in Table 2 below, the transmittance of the optical lens is shown in Table 3 below, the transmittance of the filter element is shown in Table 4 below, and the quantum efficiency of the detector is shown in Table 5 below. Figure 9 Figure 10 Figure 11

[0108] Table 2

[0109] ​​​

[0110] In some embodiments, obtaining, according to the first spectral response function of the picture element, the proportion of energy contribution of each of the multiple waveband lights to the response of the picture element includes: obtaining, according to the first spectral response function of the picture element, the proportion of energy contribution of each of the multiple waveband lights to the response of the picture element.

[0111] For any one of the sets of spectral radiance data, obtaining, according to the proportion of energy contribution of the picture element to the multiple waveband lights and according to the radiance value of the multiple waveband lights in the corresponding target light of the set, the equivalent radiance value of the multiple waveband lights received by the picture element in the corresponding target light of the set includes: for each of the multiple waveband lights, obtaining, according to the proportion of energy contribution of the waveband light and according to the radiance value of the waveband light in the corresponding target light of the set, the radiance value of the waveband light received by the picture element in the corresponding target light of the set; and obtaining, according to the radiance values of the multiple waveband lights received by the picture element in the corresponding target light of the set, the equivalent radiance value of the multiple waveband lights received by the picture element in the corresponding target light of the set.

[0112] For each of the multiple waveband lights, the radiance value of the waveband light in the corresponding target light of the set can be multiplied by the proportion of energy contribution of the waveband light to obtain the radiance value of the waveband light received by the picture element in the corresponding target light of the set, i.e., to obtain the equivalent radiance value of the waveband light received by the picture element in the corresponding target light of the set.

[0113] Summing the radiance values of the multiple waveband lights received by the picture element in the corresponding target light of the set can obtain the total radiance value of the multiple waveband lights received by the picture element in the corresponding target light of the set, i.e., to obtain the equivalent radiance value of the multiple waveband lights received by the picture element in the corresponding target light of the set.

[0114] In some embodiments, obtaining the response data of the picture element of the spectral imaging device can include: excluding weak response data and overexposure response data in the response data of the picture element, and retaining valid data in the response data of the picture element.

[0115] In some embodiments, obtaining the response data of the picture element of the spectral imaging device can include: performing dark background elimination on the response data of the picture element.

[0116] In some embodiments, obtaining the response data of the pixels of the spectral imaging device can include flat-field correction of the response data of the pixels. Illustratively, a reference response value can be selected, and the response values of the individual pixels can be normalized according to the reference response value to obtain a flat-field correction coefficient matrix. When the spectral imaging device acquires an arbitrary image, the flat-field correction coefficient matrix can be used to process the obtained image after dark background subtraction, i.e., to complete the flat-field correction. The reference response value can be the response value of a selected reference pixel, and the reference pixel can be the pixel corresponding to the vignetting center. Alternatively, the reference response value can be the average of the response values of the pixels within the vignetting center window, such as the average of the response values of the pixels within a 10*10 pixel area of the vignetting center window.

[0117] In some embodiments, according to the equivalent radiance values of the multiple wavebands of the target light received by the pixels obtained in multiple groups and the response data of the corresponding pixels in each group, the radiation response coefficient values are obtained, and obtaining the radiation response model corresponding to the radiation response coefficient values can include the following processes, including the following steps:

[0118] S151: According to the equivalent radiance values of the multiple wavebands of the target light received by the pixels obtained in multiple groups and the response data of the corresponding pixels in each group, a preset relationship is obtained, the preset relationship describes the relationship between the response value of the pixel and the total radiance of the multiple wavebands received by the pixel, and the preset relationship includes a total coefficient value representing the relationship between the response value of the pixel and the total radiance of the multiple wavebands received by the pixel.

[0119] S152: For any one of the multiple wavebands, according to the total coefficient value and the energy contribution proportion of the waveband, a radiation response coefficient value corresponding to the waveband is obtained, the radiation response coefficient value corresponding to the waveband represents the relationship between the response value of the pixel and the radiance of the waveband received by the pixel.

[0120] S153: According to the radiation response coefficient values corresponding to the multiple wavebands, the radiation response model of the pixel is obtained.

[0121] According to the equivalent radiance values of the multiple wavebands of the target light received by the pixels obtained in multiple groups and the response data of the corresponding pixels in each group, a preset relationship can be obtained by fitting. For any one of the multiple wavebands, the total coefficient value can be multiplied by the energy contribution proportion of the waveband to the pixel to obtain a radiation response coefficient value corresponding to the waveband.

[0122] Illustratively, the preset relationship of pixel j can be represented as: wherein, DN jL represents the response value of pixel j. j a represents the equivalent radiance value of the various wavelengths of light received by pixel j from the target light. j b represents the total coefficient of cell j. j Indicates bias.

[0123] Furthermore, a j Multiplying the total coefficient value by the energy contribution ratio corresponding to each of the various wavelength bands yields the radiative response coefficient value for each wavelength band. For example, for pixel R, multiplying the total coefficient value by the four energy contribution ratio values ​​in the row corresponding to pixel R in Table 1 yields the radiative response coefficient values ​​'a' for each of the four wavelength bands. 11 a 12 a 13 and a 14 Thus, the radiation response model of the R-pixel can be obtained.

[0124] In some implementations, the obtained radiation response coefficient value cannot be directly used as the final value of the radiation response coefficient based on the equivalent radiance values ​​of the various wavelengths of light received by multiple sets of pixels in the target light and the response data of each corresponding set of pixels. The obtained radiation response coefficient value is calculated by radiation response theory. However, the actual radiation response may not be completely consistent with the theoretical radiation response due to slight errors in the transmittance of the optical lens, the transmittance of the filter element, and the quantum efficiency of the detector. Therefore, correction is required.

[0125] In response to this, some implementation methods may refer to... Figure 12 , Figure 12 The flowchart of a radiometric calibration method for a spectral imaging device, provided in another embodiment, describes a method for obtaining a radiometric response coefficient value based on multiple sets of equivalent radiance values ​​of various wavelengths of light received by the pixels from the target light and the response data of each corresponding pixel. Obtaining the radiometric response model corresponding to the radiometric response coefficient value may include the following process:

[0126] S161: Based on the equivalent radiance values ​​of the various wavelengths of light received by the pixel from the target light and the response data of the corresponding pixel in each group, an initial radiation response model of the pixel is obtained, and an initial value of the radiation response coefficient is obtained. The initial value of the radiation response coefficient is the radiation response coefficient value in the initial radiation response model.

[0127] S162: establishing a target function and iteratively operating based on the target function to obtain a radiation response coefficient value satisfying a condition, so as to obtain a radiation response model of the pixel determined by the radiation response coefficient value satisfying the condition, the target function expressing a minimum difference between an actual response value of the pixel and an estimated response value of the pixel, the estimated response value of the pixel being a response value of the pixel predicted according to the radiation response model determined by a current radiation response coefficient value.

[0128] The radiation response coefficient value is obtained, and the determined radiation response model is obtained.

[0129] In the embodiment, the radiation response coefficient initial value is calculated according to the measured equivalent radiance values of the multiple groups of pixels receiving the multiple waveband lights in the target light and the response data of the corresponding pixels in each group, and the significance of the radiation response coefficient initial value is that the radiation response coefficient initial value calculated according to the measured equivalent radiance values of the multiple groups of pixels receiving the multiple waveband lights in the target light and the response data of the corresponding pixels in each group has actual physical significance, can guarantee that the final solution converges to an optimal solution with actual physical significance, and can effectively avoid the problem of obtaining a false local optimal value in the iterative solution process.

[0130] In some embodiments, the initial radiation response model of the pixel is obtained according to the obtained equivalent radiance values of the multiple groups of pixels receiving the multiple waveband lights in the target light and the response data of the corresponding pixels in each group, and the radiation response coefficient initial value is obtained, which can be obtained according to the method described in steps S151 to S153.

[0131] In some embodiments, the iteratively operating based on the target function to obtain a radiation response coefficient value satisfying a condition can include the following process:

[0132] deriving the gradient function of the target function with respect to the radiation response coefficient;

[0133] In each iteration, the current radiation response coefficient value is substituted into the gradient function to obtain a gradient value obtained in the current iteration, the radiation response coefficient value is further updated along a direction in which the value of the gradient function decreases, and the next iteration is performed by using the updated radiation response coefficient value.

[0134] The iteration is stopped when the iteration stopping condition is met, and the radiation response coefficient value obtained in the last iteration is the radiation response coefficient value satisfying the condition.

[0135] If it is the first iteration, the current radiometric response coefficient value refers to a radiometric response coefficient initial value. If it is any iteration after the first iteration, the current radiometric response coefficient value is the radiometric response coefficient value updated in the previous iteration.

[0136] In any iteration, the current radiometric response coefficient value is substituted into the gradient function, and the value of the gradient function is the gradient value obtained in the current iteration. According to the current radiometric response coefficient value, the radiometric response coefficient value is updated in a direction in which the value of the gradient function decreases.

[0137] In the embodiment, the gradient descent method is used to solve the radiometric response coefficient initial value obtained according to the measured equivalent radiance values of the pixels receiving the multiple wave bands of light and the response data of the pixels, so as to obtain an optimal solution of the radiometric response coefficient in accordance with the actual physical meaning.

[0138] In some embodiments, updating the radiometric response coefficient value in a direction in which the value of the gradient function decreases includes: taking a value obtained by subtracting a preset difference amount from the current radiometric response coefficient value as the updated radiometric response coefficient value, the preset difference amount being a product of a learning rate and the gradient value obtained in the current iteration. A suitable learning rate is set for iteration, the amplitude of the update of the radiometric response coefficient value is reduced in the iteration process, and the number of iterations is constantly changed, so as to avoid skipping the optimal solution with the physical meaning.

[0139] In some embodiments, the objective function is expressed to minimize the average value of a plurality of differences, the difference being an absolute value of a difference between an actual response value of a pixel and an estimated response value of the pixel. Exemplarily, the optimization objective function is a residual error function, and the expression of the objective function can be as follows:

[0140] ; (6)

[0141] wherein a represents a radiometric response coefficient, N represents an effective data amount, DN i true represents an actual response value of a pixel of the i th data, DN i pred represents an estimated response value of a pixel of the i th data. Since the objective function is a convex function, the radiometric response coefficient value corresponding to the extreme point is the optimal solution.

[0142] Exemplarily, the radiometric response coefficient vectors A and B are included, and the gradients of the objective function with respect to A and B are respectively solved by the following formula:

[0143] , (7).

[0144] wherein r represents the objective function.

[0145] The radiation response coefficient value can be updated in each iteration according to the following formula:

[0146] , . (8)

[0147] wherein A k+1 represents the updated radiation response coefficient vector in the kth iteration, A k represents the current radiation response coefficient vector in the kth iteration, B k+1 represents the updated radiation response coefficient vector in the kth iteration, B k represents the current radiation response coefficient vector in the kth iteration, and β represents the learning rate.

[0148] Exemplarily, for any one pixel, the radiation response coefficient of the pixel to the waveband i includes a i and b i , i = 1, 2, …, n, n represents n kinds of waveband lights, A represents a vector composed of a n , and B represents a vector composed of b i , …, b n .

[0149] Exemplarily, the following Table 3 can be referred to for the optimal solution of the radiation response coefficient obtained in a specific example.

[0150] Table 3

[0151]

[0152] In some embodiments, the radiation response model of a pixel is represented by a relationship formula in which the radiance of the waveband light received by the pixel is the independent variable, and the response value of the pixel is the dependent variable, and the response value of the pixel and the radiance of any one of the waveband lights are in a linear relationship. In some embodiments, the radiation response model of a pixel can be represented as:

[0153] ;

[0154] wherein DN represents the response value of the pixel, a i represents the radiation response coefficient corresponding to the waveband i, L(λ i ) represents the radiance of the waveband i light received by the pixel, and n represents n kinds of waveband lights.

[0155] The spatial-spectral coupling type spectral imaging process is quantitatively analyzed, the spectral spatial information coupling process of the spectral imaging device is derived according to the radiation transmission theory, and a complete radiation response model thereof is established. The parameters affecting the spectral radiation transmission are determined, including the spectral energy distribution E(λ) of the light source, the reflection spectrum function S x,y(λ), transmittance T of the optical lens lens (λ), transmittance spectrum T of the filter element filter (λ), quantum efficiency function QE(λ) of the detector, characterization coefficient K of the internal gain and aperture of the camera, coordinate position (x, y) of the pixel, and response f of the pixel x,y .

[0156] The radiation response process of the spatial-spectral coupling type spectral imaging device can be expressed by the following formula (9):

[0157] ; (9)

[0158] . (10)

[0159] E(λ) and S x,y (λ) are multiplied to obtain the reflectance spectral radiance of the target, and the modulation of the optical lens and the filter element is sequentially passed to obtain:

[0160] ; (11)

[0161] wherein L(λ) represents the radiance of the target after passing through the optical lens and the filter element, and after discretization, it is represented as:

[0162] ; (12)

[0163] wherein i=1, 2…, n, and n represents the number of through bands of the filter element, i.e. n represents n kinds of band light. Therefore, the relationship between the response of each pixel and the multi-spectral data can be established, as shown in the following formula (13). Wherein a i represents the radiation response coefficient corresponding to the band i, L(λ i ) represents the radiance of the band i light received by the pixel, and DN can be the pixel response value after removing the dark background noise.

[0164] . (13)

[0165] Then in a specific example, for a four-band spectral imaging device, and the spectral imaging device includes R pixels, G pixels, B pixels and NIR pixels, the radiation response model constructed is:

[0166] . (14)

[0167] The radiation response model takes the radiation response coefficient as an unknown quantity, and is a solution to such an over-determined equation set. By changing the target light in the spectral and radiation dimensions, enough target light states can be provided, enough radiation calibration data can be measured, and thus multiple linearly independent equations for solving the radiation response coefficient can be obtained. Based on linear algebra theory, when the number of equations is greater than or equal to the number of unknown quantities (the radiation response coefficient), a stable solution can be obtained.

[0168] In addition, in some embodiments, the meaning of calculating the initial value of the radiation response coefficient according to the measured equivalent radiance value of the pixel receiving the multiple waveband lights and the response data of the pixel is that the selection of the initial value is crucial when the gradient descent method is used to solve the over-determined equation set, because the over-determined equation set has countless optimal solutions, and different initial values can lead to different optimal solutions. Therefore, a set of initial values for iteration is first determined to ensure that the final solution converges to an optimal solution with actual physical meaning, which can effectively avoid the problem of obtaining a wrong local optimal value in the solving process of the over-determined equation set.

[0169] The embodiment also provides a spectral imaging device radiation calibration system, which is used to obtain target light and separate the target light into multiple waveband lights, and a pixel of the spectral imaging device is used to respond to the multiple waveband lights.

[0170] The spectral imaging device radiation calibration system comprises:

[0171] A light source device is configured to emit target light.

[0172] A measurement device is configured to measure the spectral radiance of the target light.

[0173] A processing device is connected to the light source device and the measurement device, respectively, and is configured to perform the steps of the spectral imaging device radiation calibration method according to any one of the above embodiments.

[0174] The spectral imaging device radiation calibration system of the embodiment realizes the radiation calibration of the spectral imaging device that couples spectral information and spatial information.

[0175] Reference can be made to Figure 3 As shown in the figure, a plurality of light sources 101 are arranged in the integrating sphere 100, and the plurality of light sources 101 include multiple light sources emitting light with different spectra. The target light is emitted from the integrating sphere 100. The spectral imaging device 103 obtains the target light to obtain the response data of the pixel, and the measurement device 102 measures the spectral radiance of the target light. The processing device 104 is connected to the integrating sphere 100, the measurement device 102, and the spectral imaging device 103, respectively.

[0176] The radiation response model of the spectral imaging device constructed by the method and system, the radiation calibration method of the multi-light source combination and the radiation response coefficient solving method effectively solve the problem that the spectral and spatial information of the spatial-spectral coupling type spectral imaging device are coupled together for radiation calibration, and improve the radiation calibration precision.

[0177] The method and system are aimed at the spatial-spectral coupling type spectral imaging device, construct a radiation response model describing the complete spectral radiation transmission process according to the radiation transmission theory, propose a laboratory radiation calibration method using multi-light source combination based on the constructed radiation response model, realize the change of the light source in the spectral and radiation two dimensions, and thus obtain the over-determined equation group about the radiation response coefficient. The energy contribution proportion of each waveband is calculated according to the spectral response, and is converted into the initial value of the radiation response coefficient, which can effectively avoid the problem of obtaining the wrong local optimal value in the over-determined equation group solving process, and the gradient descent method is used to calculate the optimal solution of the radiation response coefficient with practical physical meaning, and the precision and stability of the radiation response coefficient solving are improved by combining the theoretical calculation with the calibration data.

[0178] The spectral imaging device radiation calibration method and system provided by the present application are described in detail above. The principles and implementation modes of the present application are described by applying specific examples in this paper, and the above embodiment description is only used to help understand the method of the present application and its core idea. It should be pointed out that, for those skilled in the art, some improvements and modifications can be made to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A method of radiometric calibration of a spectral imaging device, characterized in that, The spectral imaging device is used to acquire target light and separate the target light into multiple waveband lights, and a pixel of the spectral imaging device is used to respond to the multiple waveband lights; The radiation calibration method of the spectral imaging device comprises: constructing a radiation response model of a pixel of the spectral imaging device, the radiation response model of the pixel describing a relationship between a response value of the pixel and an irradiance of the multiple waveband lights received by the pixel, and the radiation response model comprising a radiation response coefficient; controlling the target light to vary in the spectral dimension and the radiation dimension, measuring spectral radiance of the target light and causing the spectral imaging device to acquire the target light to obtain the response value of the pixel under different spectral or / and irradiance of the target light, and obtaining multiple sets of spectral radiance data of the target light and response data of the pixel; for any one set of the spectral radiance data, obtaining an irradiance value of any one waveband light of the multiple waveband lights in the corresponding target light of the set according to the spectral radiance data of the set; obtaining a proportion of energy contribution of the multiple waveband lights to the response of the pixel according to a first spectral response function of the pixel, and for any one set of the spectral radiance data, obtaining an equivalent irradiance value of the multiple waveband lights in the corresponding target light of the set received by the pixel according to the proportion of energy contribution of the multiple waveband lights to the pixel and according to the irradiance value of the multiple waveband lights in the corresponding target light of the set, the first spectral response function of the pixel describing a response capability of the pixel to different wavelengths of light when light enters the spectral imaging device; obtaining a radiation response coefficient value according to the equivalent irradiance values of the multiple waveband lights in the target light received by the pixel and the response data of the pixel corresponding to each set, and obtaining the radiation response model corresponding to the radiation response coefficient value.

2. The method of spectral imaging device radiometric calibration according to claim 1, characterized in that, The controlling the target light to vary in the spectral dimension and the radiation dimension comprises: mixing emission lights of multiple light sources to form the target light, the emission spectrums of the multiple light sources being different, and controlling energy proportions of the emission lights of the multiple light sources to vary so that the target light varies in the spectral dimension and the radiation dimension.

3. The method of spectral imaging device radiometric calibration according to claim 1, characterized in that, mixing emission lights of a first light source and a second light source to form the target light, the emission spectrums of the first light source and the second light source being different; The controlling the target light to vary in the spectral dimension and the radiation dimension, measuring spectral radiance of the target light and causing the spectral imaging device to acquire the target light to obtain the response value of the pixel under different target light states comprises: changing emission light brightness of the first light source in a first preset step by step, changing emission light brightness of the second light source in a second preset step by step under each brightness level of the first light source, and measuring spectral radiance of the target light and obtaining the response value of the pixel of the spectral imaging device under each brightness level of the second light source.

4. The method of spectral imaging device radiometric calibration according to claim 1, characterized in that, The proportion of energy of the multiple wavebands of light that causes the picture element to respond according to the first spectral response function of the picture element includes: For any one waveband of light, integrating the first spectral response function over a wavelength range of the waveband of light to obtain a first integral value, and integrating the first spectral response function over a wavelength range of the multiple wavebands of light to obtain a second integral value, the proportion of energy of the waveband of light to the picture element is obtained according to a ratio of the first integral value to the second integral value.

5. The method of spectral imaging device radiometric calibration according to claim 1, characterized in that, The proportion of energy of the multiple wavebands of light that causes the picture element to respond according to the first spectral response function of the picture element includes: The proportion of energy of the multiple wavebands of light that causes the picture element to respond according to the first spectral response function of the picture element includes: For any one waveband of light, integrating the first spectral response function over a wavelength range of the waveband of light to obtain a first integral value, and integrating the first spectral response function over a wavelength range of the multiple wavebands of light to obtain a second integral value, the proportion of energy of the waveband of light to the picture element is obtained according to a ratio of the first integral value to the second integral value. The proportion of energy of the multiple wavebands of light that causes the picture element to respond according to the first spectral response function of the picture element includes: For any one waveband of light, integrating the first spectral response function over a wavelength range of the waveband of light to obtain a first integral value, and integrating the first spectral response function over a wavelength range of the multiple wavebands of light to obtain a second integral value, the proportion of energy of the waveband of light to the picture element is obtained according to a ratio of the first integral value to the second integral value.

6. The method according to any one of claims 1 to 5, wherein The proportion of energy of the multiple wavebands of light that causes the picture element to respond according to the first spectral response function of the picture element includes: For any one waveband of light, integrating the first spectral response function over a wavelength range of the waveband of light to obtain a first integral value, and integrating the first spectral response function over a wavelength range of the multiple wavebands of light to obtain a second integral value, the proportion of energy of the waveband of light to the picture element is obtained according to a ratio of the first integral value to the second integral value. The proportion of energy of the multiple wavebands of light that causes the picture element to respond according to the first spectral response function of the picture element includes: For any one waveband of light, integrating the first spectral response function over a wavelength range of the waveband of light to obtain a first integral value, and integrating the first spectral response function over a wavelength range of the multiple wavebands of light to obtain a second integral value, the proportion of energy of the waveband of light to the picture element is obtained according to a ratio of the first integral value to the second integral value.

7. The method according to any one of claims 1 to 5, wherein The proportion of energy of the multiple wavebands of light that causes the picture element to respond according to the first spectral response function of the picture element includes: For any one waveband of light, integrating the first spectral response function over a wavelength range of the waveband of light to obtain a first integral value, and integrating the first spectral response function over a wavelength range of the multiple wavebands of light to obtain a second integral value, the proportion of energy of the waveband of light to the picture element is obtained according to a ratio of the first integral value to the second integral value. The proportion of energy of the multiple wavebands of light that causes the picture element to respond according to the first spectral response function of the picture element includes: For any one waveband of light, integrating the first spectral response function over a wavelength range of the waveband of light to obtain a first integral value, and integrating the first spectral response function over a wavelength range of the multiple wavebands of light to obtain a second integral value, the proportion of energy of the waveband of light to the picture element is obtained according to a ratio of the first integral value to the second integral value. According to the equivalent radiance values of the multiple wavebands of the target light received by the pixels and the response data of the corresponding pixels in each group, an initial radiation response model of the pixels is obtained, and an initial value of a radiation response coefficient is obtained, the initial value of the radiation response coefficient being a value of a radiation response coefficient in the initial radiation response model; A target function is established, and iterative operation is performed based on the target function, to obtain a value of the radiation response coefficient that meets a condition, so as to obtain the radiation response model of the pixels determined by the value of the radiation response coefficient that meets the condition, the target function expressing that a difference between an actual response value of the pixels and an estimated response value of the pixels is minimized, the estimated response value of the pixels being a predicted response value of the pixels determined according to the radiation response model with the current value of the radiation response coefficient.

8. The method of spectral imaging device radiometric calibration according to claim 7, characterized in that, The iterative operation based on the target function to obtain the value of the radiation response coefficient that meets the condition includes: deriving the target function with respect to the radiation response coefficient to obtain a gradient function of the target function with respect to the radiation response coefficient; in each iteration, substituting the current value of the radiation response coefficient into the gradient function to obtain a gradient value obtained in the current iteration, and further updating the value of the radiation response coefficient in a direction in which the value of the gradient function decreases, so that the next iteration is performed with the updated value of the radiation response coefficient; stopping the iteration when an iteration stop condition is met, and the value of the radiation response coefficient obtained in the last iteration being the value of the radiation response coefficient that meets the condition.

9. The method of spectral imaging device radiometric calibration according to claim 8, characterized in that, The updating of the value of the radiation response coefficient in the direction in which the value of the gradient function decreases includes: the updated value of the radiation response coefficient being a value obtained by subtracting a preset difference from the current value of the radiation response coefficient, the preset difference being a product of a learning rate and the gradient value obtained in the current iteration.

10. A spectral imaging device radiometric calibration system, characterized by, The spectral imaging device is configured to obtain target light and separate the target light into multiple wavebands of light, and a pixel of the spectral imaging device is configured to respond to the multiple wavebands of light; The spectral imaging device radiation calibration system includes: a light source device configured to emit target light; a measurement device configured to measure the spectral radiance of the target light; a processing device connected to the light source device and the measurement device, respectively, and configured to perform the steps of the spectral imaging device radiation calibration method according to any one of claims 1 to 9.

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