Spectral sensor calibration method and device under low illumination conditions

Abstract

This application proposes a method and device for calibrating a spectral sensor under low-light conditions. The method includes: constructing a calibration optical system, which consists of a standard low-light adjustable light source and a converging optical path; providing a motion unit for the spectral sensor to be calibrated; adjusting the wavelength output by the calibration optical system, moving the motion unit at each wavelength, obtaining an imaging unit response map for each position in the imaging array, and splicing the individual imaging unit response maps at the same wavelength into an array calibration image through an algorithm. The array calibration images at different wavelengths are matched with the spectral information of the calibration optical system to generate a data set reflecting the relationship between the spectral sensor response and the calibration spectrum; inverting the data set through an inversion algorithm to obtain the spectral response of the spectral sensor to complete the calibration. This method can perform complete and accurate spectral sensor calibration under low-light conditions by combining spot scanning and image splicing.

Description

Technical Field

[0001] The present application relates to the technical field of spectral sensor calibration, and in particular to a spectral sensor calibration method and device under low illumination conditions. Background Art

[0002] Currently, spectral sensors are widely used in various fields, including environmental monitoring, remote sensing control, biochemical analysis, and agricultural monitoring. Spectral sensors can acquire spectral information of target substances, thereby providing information on their composition and content, making them a valuable tool in various fields. Therefore, spectral imaging research is of great significance.

[0003] In recent years, the popularity of snapshot spectral imaging systems has gradually increased. The most representative are spectral sensors that use a combination of a filter layer and a detector. The filter layer is a filter film array formed by printing broadband materials such as quantum dots and polymers. Based on the principle of spectral multiplexing, the broadband properties of the filter material enable the system to achieve higher light throughput without sacrificing spatial, spectral, and temporal resolution, while also achieving a smaller size and higher integration.

[0004] In related technologies, when calibrating sensors based on broadband material spectral multiplexing filters, an indirect calibration method is generally used. That is, a standard light source is used to illuminate the entire imaging surface of the sensor to obtain the sensor's spectral response image, and then the response of the spectral sensor is calibrated in a data-driven manner.

[0005] However, for some special wavelengths, such as the long-wave infrared and very-long-wave infrared bands, due to limitations in light source technology, only blackbody light sources can be used. However, the spectral density of blackbody light sources is low, resulting in low illumination for a single wavelength band, which is insufficient to illuminate the entire sensor, making complete sensor calibration difficult.

[0006] Therefore, how to completely and accurately calibrate spectral sensors under low illumination conditions has become an urgent problem that needs to be solved. Summary of the Invention

[0007] The present application aims to solve one of the technical problems in the related art at least to a certain extent.

[0008] To this end, the first purpose of this application is to propose a spectral sensor calibration method under low illumination conditions, which can perform complete and accurate spectral sensor calibration under low illumination conditions through spot scanning and image stitching.

[0009] The second object of this application is to provide a spectral sensor calibration device under low illumination conditions;

[0010] The third object of this application is to provide an electronic device;

[0011] A fourth object of the present application is to provide a non-transitory computer-readable storage medium.

[0012] To achieve the above objectives, the first aspect of the present application is to propose a spectral sensor calibration method under low illumination conditions, the method comprising the following steps:

[0013] Build a calibration optical system, wherein the calibration optical system consists of a standard low-illuminance adjustable light source with a known spectrum and a converging light path, wherein the converging light path is used to enhance the illumination brightness of the light spot output by the standard low-illuminance adjustable light source;

[0014] Setting a motion unit for the spectral sensor to be calibrated, and moving the imaging array of the spectral sensor by the motion unit to control the light spot output by the calibration optical system to illuminate each position of the imaging array;

[0015] The wavelength output by the calibration optical system is sequentially adjusted according to a preset sequence, the motion unit is moved at each wavelength, an imaging unit response map at each position in the imaging array is obtained, and the imaging unit response maps at the same wavelength are stitched together into an array calibration image using a stitching algorithm. The array calibration images at different wavelengths are matched with the spectral information of the calibration optical system to generate a data set reflecting the relationship between the spectral sensor response and the calibration spectrum;

[0016] An inversion algorithm is designed, and an inversion calculation is performed on the data set by the inversion algorithm to obtain a spectral response of the spectral sensor, and the spectral response is used to complete the calibration of the spectral sensor.

[0017] Optionally, in one embodiment of the present application, after generating a data set reflecting the relationship between the spectral sensor response and the calibrated spectrum, it also includes: constructing a neural network model based on a codec architecture, and training the neural network model through the data set; deploying the trained neural network model, and performing spectral reconstruction on the data collected by the spectral sensor through the trained neural network model.

[0018] Optionally, in one embodiment of the present application, the converging light path is used to reduce the light spot output by the standard low-illuminance adjustable light source, wherein the illumination brightness of the reduced light spot is greater than or equal to the illumination brightness required to illuminate the area corresponding to the light spot.

[0019] Optionally, in one embodiment of the present application, the motion unit is a translation stage or an adjustable reflector, and setting the motion unit for the spectral sensor to be calibrated includes: setting the spectral sensor on the translation stage to drive the imaging array to move through the translation stage.

[0020] Optionally, in one embodiment of the present application, the stitching algorithm includes a feature point-based image stitching algorithm and a region-based image stitching algorithm.

[0021] To achieve the above objectives, the second aspect of the present application further proposes a spectral sensor calibration device under low illumination conditions, comprising the following modules:

[0022] A construction module for constructing a calibration optical system, wherein the calibration optical system is composed of a standard low-illuminance adjustable light source with a known spectrum and a converging light path, wherein the converging light path is used to enhance the illumination brightness of the light spot output by the standard low-illuminance adjustable light source;

[0023] a setting module, configured to set a motion unit for the spectral sensor to be calibrated, and move the imaging array of the spectral sensor by means of the motion unit, so as to control the light spot output by the calibration optical system to illuminate each position of the imaging array;

[0024] a generation module for sequentially adjusting the wavelength output by the calibration optical system according to a preset sequence, moving the motion unit at each wavelength to obtain an imaging unit response map at each position in the imaging array, and stitching the imaging unit response maps at the same wavelength into an array calibration image using a stitching algorithm, matching the array calibration images at different wavelengths with the spectral information of the calibration optical system, and generating a data set reflecting the relationship between the spectral sensor response and the calibration spectrum;

[0025] The calibration module is used to design an inversion algorithm, perform inversion calculation on the data set through the inversion algorithm to obtain the spectral response of the spectral sensor, and complete the calibration of the spectral sensor using the spectral response.

[0026] To achieve the above-mentioned purpose, the third aspect of the present application further proposes an electronic device, comprising:

[0027] processor;

[0028] a memory for storing instructions executable by the processor;

[0029] The processor is configured to execute the instructions to implement the spectral sensor calibration method under low illumination conditions as described in any one of the first aspects above.

[0030] To achieve the above-mentioned purpose, the fourth aspect embodiment of the present application also proposes a non-temporary computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the spectral sensor calibration method under low-light conditions described in any one of the above-mentioned first aspects.

[0031] The technical solutions provided by the embodiments of this application provide at least the following beneficial effects: The present application first constructs a calibration optical system for sensor calibration under low-light conditions. A motion unit is added to the calibration optical system to move part of the spectral imaging system, ensuring that the light spot after passing through the calibration optical system can scan the entire imaging array. The wavelength of the calibration light source is then changed in a certain sequence. The motion system is moved under each wavelength condition so that the focused light spot scans the entire imaging surface of the sensor. An algorithm is used to stitch the light spots after each shift, obtaining complete array calibration images at different wavelengths, forming a sensor response-calibration spectral dataset. Finally, an inversion algorithm is designed to obtain the sensor's spectral response from the obtained dataset. Thus, the present application obtains a complete spectral response image of the spectral sensor imaging surface through light spot scanning and image stitching, enabling complete spectral sensor calibration under low-light conditions. The constructed system verifies the reliability of the calibration principle. Furthermore, high-precision spectral reconstruction can be achieved under low-light conditions. Consequently, the present application improves the integrity, accuracy, and applicability of spectral sensor calibration under low-light conditions.

[0032] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0034] Figure 1 This is a flow chart of a spectral sensor calibration method under low illumination conditions proposed in an embodiment of the present application;

[0035] Figure 2 A schematic diagram of a specific spectral sensor calibration scenario proposed in an embodiment of the present application;

[0036] Figure 3 A flowchart of spectral reconstruction for a spectral sensor to be calibrated proposed in an embodiment of the present application;

[0037] Figure 4 This is a structural schematic diagram of a spectral sensor calibration device under low illumination conditions proposed in an embodiment of the present application. DETAILED DESCRIPTION

[0038] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0039] A method and apparatus for calibrating a spectral sensor under low illumination conditions proposed in an embodiment of the present application will be described in detail below with reference to the accompanying drawings.

[0040] Figure 1 This is a flow chart of a spectral sensor calibration method under low illumination conditions proposed in an embodiment of the present application, such as Figure 1 As shown, the method includes the following steps:

[0041] Step S101 : constructing a calibration optical system, wherein the calibration optical system is composed of a standard low-illuminance adjustable light source with a known spectrum and a converging light path, wherein the converging light path is used to enhance the illumination brightness of a light spot output by the standard low-illuminance adjustable light source.

[0042] Specifically, a calibration optical system is first built to calibrate the spectral sensor under low-light conditions. This calibration optical system can simulate low-light conditions and includes a known standard light source. Specifically, the calibration optical system consists of a standard low-light tunable light source with a known spectrum and a converging optical path.

[0043] A standard low-light tunable light source cannot provide sufficient illumination to directly illuminate the entire sensor imaging surface in all required wavelengths, thus enabling spectral sensor calibration under low-light conditions. For example, a standard blackbody light source can be used. A converging optical path is used to enhance the brightness of the light spot output by the standard low-light tunable light source. That is, after the light spot output by the standard low-light tunable light source passes through the converging optical path, it can provide sufficient illumination brightness in a local area, illuminating that area.

[0044] In one embodiment of the present application, a converging light path is used to reduce the light spot output by a standard low-light adjustable light source, wherein the illumination brightness of the reduced light spot is greater than or equal to the illumination brightness required to illuminate the area corresponding to the light spot. Specifically, the converging light path of this embodiment uses a method of reducing the light spot to provide sufficient illumination within a certain area. The illumination brightness of the reduced light spot output by the converging light path within its illuminated area is greater than or equal to the illumination brightness required to illuminate the area illuminated by the light spot.

[0045] Therefore, the present application can obtain an illumination spot with sufficient luminous flux through a low-illuminance light source and a converging light path, and the spectrum of the light source is known. The light waves output by the standard low-illuminance adjustable light source can be adjusted to the various bands required for the calibration of the spectral sensor.

[0046] Step S102 : setting a motion unit for the spectral sensor to be calibrated, and moving the imaging array of the spectral sensor by the motion unit to control the light spot output by the calibration optical system to illuminate each position of the imaging array.

[0047] Specifically, a motion unit is added behind the calibration optical system. This motion unit is used to move the spectral sensor. The motion unit adjusts the spectral sensor's position to ensure that the light spot output by the calibration optical system sweeps across the entire imaging array of the spectral sensor. In other words, the motion unit moves the imaging array so that the light spot after passing through the calibration optical system can illuminate every position in the imaging array.

[0048] In one embodiment of the present application, the motion unit is a translation stage or an adjustable reflector, and setting the motion unit for the spectral sensor to be calibrated includes: setting the spectral sensor on the translation stage to drive the imaging array to move through the translation stage.

[0049] For example, if Figure 2 As shown, when the motion unit 30 is a translation stage, the multispectral imaging sensor 40 is placed on the translation stage, and the standard low-light adjustable light source 10 and the converging light path 20 are placed in front of the multispectral imaging sensor 40. The motion unit 30 can drive the multispectral imaging sensor 40 above to move in different directions, and the motion unit 30 can be continuously adjusted so that the light spot output by the converging light path 20 can completely scan the entire area of the imaging array in the multispectral imaging sensor 40.

[0050] Therefore, the present application changes the position where the light spot is irradiated onto the imaging array through the motion unit, ensuring that the illumination response image of each position on the imaging array can be obtained after multiple movements.

[0051] In step S103, the wavelength output by the calibration optical system is adjusted in sequence according to a preset order. The motion unit is moved at each wavelength to obtain an imaging unit response map at each position in the imaging array. The imaging unit response maps at the same wavelength are stitched together into an array calibration image through a stitching algorithm. The array calibration images at different wavelengths are matched with the spectral information of the calibration optical system to generate a data set reflecting the relationship between the spectral sensor response and the calibration spectrum.

[0052] Specifically, the wavelength of the standard low-illuminance adjustable light source is changed in a certain order, and under the condition of each output wavelength, the motion unit is moved so that the focused light spot gradually scans the entire imaging array of the spectral sensor. Since the light spot can only scan a part of the area after each movement, the imaging unit response map under the current irradiation position can be obtained. Therefore, the present application also uses an algorithm to splice the imaging unit response map obtained by the light spot irradiation after each movement of the motion unit to obtain a complete array calibration image of the imaging array under the current wavelength condition. Then switch to the next wavelength and repeat the above movement and splicing operations to obtain a pair of complete array calibration images under different bands. The array calibration image obtained at each wavelength is then matched with the spectral information of the standard low-illuminance adjustable light source at the corresponding wavelength to form a sensor response-calibration spectrum data set.

[0053] Among them, the wavelengths output by the standard low-illuminance adjustable light source are the wavelengths required for calibrating the spectral sensor. The wavelengths of the light waves output by the standard low-illuminance adjustable light source can be adjusted in sequence from small to large for easy switching.

[0054] In one embodiment of the present application, when images of multiple light spots at different positions under the same wavelength are stitched into one image as a data set for camera calibration, stitching algorithms include: feature point-based image stitching algorithm and region-based image stitching algorithm.

[0055] Specifically, various algorithms capable of image stitching can be used. For example, feature point-based image stitching algorithms include, but are not limited to, the Scale-Invariant Feature Transform (SIFT) algorithm, the Speeded Up Robust Features (SURF) algorithm, and the BRISK algorithm. Region-based image stitching algorithms include, but are not limited to, various local adaptive warping algorithms and various optimal seam stitching algorithms.

[0056] Therefore, this application changes the wavelength of the calibration optical system and moves the motion unit to obtain the imaging unit response diagram at each position under all illumination bands, and then splices the images under the same wavelength into one image, which corresponds to the spectral information of the standard low-illuminance adjustable light source, and generates a sensor response-calibration spectral data set that reflects the relationship between the spectral sensor response and the standard light source spectrum.

[0057] Step S104 : designing an inversion algorithm, performing inversion calculation on the data set through the inversion algorithm, obtaining the spectral response of the spectral sensor, and completing the calibration of the spectral sensor using the spectral response.

[0058] Specifically, an inversion algorithm is designed, and the spectral response of the spectral sensor to be calibrated is obtained by applying the inversion algorithm to the data set obtained in the previous step, and then the obtained spectral response of the sensor is calibrated.

[0059] The specific implementation method of completing the calibration of the spectral sensor using the obtained spectral response may refer to the spectral sensor calibration method in the relevant embodiments, for example, calibrating the response of the spectral sensor in a data-driven manner.

[0060] The inversion algorithm designed in this application is based on a known standard light source. Therefore, the inversion algorithms that can be used include least squares and matrix solvers. As an example, assuming that the response of the spectral sensor is proportional to the calibration spectrum, the spectral response of the spectral sensor can be inverted based on the measured data and the spectral information of the standard low-illuminance adjustable light source by performing mathematical operations using the inversion algorithm.

[0061] In summary, the spectral sensor calibration method under low-light conditions in the embodiments of the present application first constructs a calibration optical system for sensor calibration under low-light conditions. A motion unit is added to the calibration optical system to move part of the spectral imaging system, ensuring that the light spot after passing through the calibration optical system can scan the entire imaging array. The wavelength of the calibration light source is then changed in a certain sequence. The motion system is moved under each wavelength condition so that the focused light spot scans the entire imaging surface of the sensor. An algorithm is used to stitch the light spots after each movement to obtain a pair of complete array calibration images at different wavelengths, forming a sensor response-calibration spectral dataset. Finally, an inversion algorithm is designed to obtain the sensor's spectral response from the obtained dataset. Thus, this method, through light spot scanning and image stitching, obtains a complete spectral response image of the spectral sensor imaging surface, enabling complete spectral sensor calibration under low-light conditions. The constructed system can verify the reliability of the calibration principle. Furthermore, high-precision spectral reconstruction can be achieved under low-light conditions. Consequently, this method improves the integrity, accuracy, and applicability of spectral sensor calibration under low-light conditions.

[0062] Based on the above embodiments, the present application can also achieve high-precision spectral reconstruction under low-light conditions. Specifically, in one embodiment of the present application, after generating a dataset reflecting the relationship between the spectral sensor response and the calibration spectrum, the process further includes: constructing a neural network model based on a codec architecture and training the neural network model using the dataset; deploying the trained neural network model, and using the trained neural network model to perform spectral reconstruction on the data collected by the spectral sensor.

[0063] Specifically, in order to more clearly illustrate the specific implementation process of the present application for spectral reconstruction of the spectral sensor to be calibrated, a spectral reconstruction method proposed in this embodiment is exemplified below. Figure 3 A flowchart of a spectrum reconstruction for a spectral sensor to be calibrated is proposed in an embodiment of the present application, such as Figure 3 As shown, the process includes the following steps:

[0064] Step S301: Building a multispectral sensor calibration system under low illumination conditions.

[0065] Step S302: calibrate i groups of camera position response images in different bands, where i is a positive integer determined according to the number of bands required for camera calibration.

[0066] Step S303 : Using an algorithm, images at different sensor positions in each band are stitched together to obtain a data set corresponding to i groups of spectra and images.

[0067] Step S304: Constructing an encoder-decoder architecture neural network. The neural network can be any model using an encoder-decoder architecture, such as an LSTM model and a Transformer model, and the specific model is determined based on actual needs.

[0068] Step S305: Use the concatenated i groups of data sets to train the network.

[0069] Step S306: Deploy the trained network model to reconstruct the data collected by the sensor and restore the hyperspectral data. The model training and deployment methods, as well as the process of using the model for reconstruction, can be referenced to the implementation methods in the relevant embodiments and are not limited in this application.

[0070] In order to implement the above embodiment, the present application also proposes a spectral sensor calibration device under low illumination conditions. Figure 4 This is a structural diagram of a spectral sensor calibration device under low illumination conditions proposed in an embodiment of the present application, such as Figure 4 As shown, the device includes a building module 100 , a setting module 200 , a generating module 300 and a calibration module 400 .

[0071] Among them, the building module 100 is used to build a calibration optical system, wherein the calibration optical system consists of a standard low-illuminance adjustable light source with a known spectrum and a converging light path, which is used to enhance the illumination brightness of the light spot output by the standard low-illuminance adjustable light source.

[0072] The setting module 200 is used to set a motion unit for the spectral sensor to be calibrated, and move the imaging array of the spectral sensor through the motion unit to control the light spot output by the calibration optical system to illuminate each position of the imaging array.

[0073] Generation module 300 is used to sequentially adjust the wavelength output by the calibration optical system in a preset order, move the motion unit at each wavelength, obtain the imaging unit response map at each position in the imaging array, and stitch the individual imaging unit response maps at the same wavelength into an array calibration image through a stitching algorithm. The array calibration images at different wavelengths are matched with the spectral information of the calibration optical system to generate a data set reflecting the relationship between the spectral sensor response and the calibration spectrum.

[0074] The calibration module 400 is used to design an inversion algorithm, perform inversion calculation on the data set through the inversion algorithm, obtain the spectral response of the spectral sensor, and complete the calibration of the spectral sensor using the spectral response.

[0075] Optionally, in one embodiment of the present application, the device further includes: a training module for constructing a neural network model based on a codec architecture and training the neural network model through a data set; a reconstruction module for deploying the trained neural network model and performing spectral reconstruction on the data collected by the spectral sensor through the trained neural network model.

[0076] Optionally, in one embodiment of the present application, the setting module 200 is specifically configured to: set the spectral sensor on a translation stage, so as to drive the imaging array to move via the translation stage.

[0077] It should be noted that the above explanation of the embodiment of the spectral sensor calibration method under low illumination conditions is also applicable to the device of this embodiment and will not be repeated here.

[0078] In summary, the spectral sensor calibration device for low-light conditions in the embodiments of the present application, through spot scanning and image stitching, obtains a complete spectral response image of the spectral sensor imaging surface. This allows for complete spectral sensor calibration under low-light conditions, and the constructed system verifies the reliability of this calibration principle. Furthermore, it can achieve high-precision spectral reconstruction under low-light conditions. Consequently, this device improves the integrity, accuracy, and applicability of spectral sensor calibration under low-light conditions.

[0079] In order to implement the above embodiments, the present application also proposes an electronic device, which includes: a processor; a memory for storing processor-executable instructions; wherein the processor is configured to execute instructions to implement the spectral sensor calibration method under low illumination conditions as described in any one of the above-mentioned first aspect embodiments.

[0080] In order to implement the above embodiments, the present application also proposes a non-temporary computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, it implements the spectral sensor calibration method under low illumination conditions as described in any of the above-mentioned first aspect embodiments.

[0081] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0082] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0083] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present application belong.

[0084] The logic and / or steps represented in a flowchart or otherwise described herein, for example, can be considered a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" is any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (not exhaustive) of computer-readable media include: an electrical connection with one or more wires (electronic devices), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). Furthermore, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing it in another suitable manner if necessary, and then storing it in a computer memory.

[0085] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having logic gate circuits for implementing logical functions on data signals, an application-specific integrated circuit having suitable combinational logic gate circuits, a programmable gate array (PGA), a field-programmable gate array (FPGA), etc.

[0086] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0087] In addition, the functional units in the various embodiments of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into a module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0088] The storage medium mentioned above may be a read-only memory, a magnetic disk, or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application. Persons skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A method for calibrating a spectral sensor under low illumination conditions, characterized in that: The following steps are involved: Build a calibration optical system, wherein the calibration optical system consists of a standard low-illuminance adjustable light source with a known spectrum and a converging light path, wherein the converging light path is used to enhance the illumination brightness of the light spot output by the standard low-illuminance adjustable light source; Setting a motion unit for the spectral sensor to be calibrated, and moving the imaging array of the spectral sensor by the motion unit to control the light spot output by the calibration optical system to illuminate each position of the imaging array; The wavelength output by the calibration optical system is sequentially adjusted according to a preset sequence, the motion unit is moved at each wavelength, an imaging unit response map at each position in the imaging array is obtained, and the imaging unit response maps at the same wavelength are stitched together into an array calibration image using a stitching algorithm. The array calibration images at different wavelengths are matched with the spectral information of the calibration optical system to generate a data set reflecting the relationship between the spectral sensor response and the calibration spectrum; Designing an inversion algorithm, performing inversion calculation on the data set using the inversion algorithm to obtain a spectral response of the spectral sensor, and using the spectral response to complete calibration of the spectral sensor; The converging light path is used to reduce the light spot output by the standard low-illuminance adjustable light source, wherein the illumination brightness of the reduced light spot is greater than or equal to the illumination brightness required to illuminate the area corresponding to the light spot.

2. The method according to claim 1, characterized in that After generating a data set reflecting the relationship between the spectral sensor response and the calibration spectrum, the method further includes: Constructing a neural network model based on a codec architecture, and training the neural network model using the dataset; The trained neural network model is deployed, and spectral reconstruction is performed on the data collected by the spectral sensor using the trained neural network model.

3. The method according to claim 1, characterized in that The motion unit is a displacement stage or an adjustable reflector, and the motion unit is provided for the spectral sensor to be calibrated, including: The spectral sensor is arranged on the translation stage, so as to drive the imaging array to move via the translation stage.

4. The method according to claim 1, wherein The stitching algorithm includes an image stitching algorithm based on feature points and an image stitching algorithm based on regions.

5. A spectral sensor calibration device under low illumination conditions, characterized in that: Includes the following modules: A construction module for constructing a calibration optical system, wherein the calibration optical system is composed of a standard low-illuminance adjustable light source with a known spectrum and a converging light path, wherein the converging light path is used to enhance the illumination brightness of the light spot output by the standard low-illuminance adjustable light source; a setting module, configured to set a motion unit for the spectral sensor to be calibrated, and move the imaging array of the spectral sensor by means of the motion unit, so as to control the light spot output by the calibration optical system to illuminate each position of the imaging array; a generation module for sequentially adjusting the wavelength output by the calibration optical system according to a preset sequence, moving the motion unit at each wavelength to obtain an imaging unit response map at each position in the imaging array, and stitching the imaging unit response maps at the same wavelength into an array calibration image using a stitching algorithm, matching the array calibration images at different wavelengths with the spectral information of the calibration optical system, and generating a data set reflecting the relationship between the spectral sensor response and the calibration spectrum; a calibration module, configured to design an inversion algorithm, perform inversion calculation on the data set using the inversion algorithm to obtain a spectral response of the spectral sensor, and calibrate the spectral sensor using the spectral response; The converging light path is used to reduce the light spot output by the standard low-illuminance adjustable light source, wherein the illumination brightness of the reduced light spot is greater than or equal to the illumination brightness required to illuminate the area corresponding to the light spot.

6. The device according to claim 5, characterized in that Also includes: A training module, configured to construct a neural network model based on a codec architecture and train the neural network model using the dataset; The reconstruction module is used to deploy the trained neural network model and perform spectral reconstruction on the data collected by the spectral sensor through the trained neural network model.

7. The device according to claim 5, characterized in that The motion unit may be a displacement stage, and the setting module is specifically used for: The spectral sensor is arranged on the translation stage, so as to drive the imaging array to move via the translation stage.

8. An electronic device comprising: processor; a memory for storing instructions executable by the processor; The processor is configured to execute the instructions to implement the spectral sensor calibration method under low illumination conditions according to any one of claims 1 to 4.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for calibrating a spectral sensor under low illumination conditions according to any one of claims 1 to 4 is implemented.

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