Data correction method and device of micro-nano structure spectral camera

Abstract

The application discloses a kind of data correction method and device of micro-nano structure spectral camera, it is related to spectral imaging technical field.The method includes: the half field angle of spectral camera is symmetrically divided into several angle subzones along the direction of main optical axis, correspondingly different incidence angle range respectively;Original spectral data is preprocessed;The row image element of the same wavelength section in imaging sensor is divided according to angle subzone, and the mapping relationship with incidence angle is established;Each row image element is configured with micro-nano structure optical filter matching its incidence angle range;Select the image element data that incidence angle meets the response range of optical filter, and splice according to row order, generate corrected spectrum and output full-band correction result.Through the construction based on incidence angle mapping, image element partition, matching type micro-nano structure optical filter configuration and angle dominant data splicing strategy, full-band spectral data correction with high consistency, high precision and spatial continuity is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of spectral imaging technology, in particular to a data correction method and device for a micro-nano structure spectral camera. BACKGROUND

[0002] A spectral camera is a camera that can capture different spectral information at the same time. It can provide more abundant and accurate image data than traditional single-band cameras, so it is widely used in remote sensing, medical imaging, agricultural monitoring and other fields. Spectral cameras usually use multiple filters to achieve selective filtering of different wavebands. Micro-nano structure filters (such as photonic crystals, super surfaces, etc.) are widely used in spectral cameras because they are smaller in size and can provide higher spectral resolution. However, the performance of micro-nano structure filters is sensitive to the angle of incident light. In theory, the incident light in the design of the optical path of the spectral camera should be parallel light. However, in actual application, due to the existence of the field of view angle of the camera, the angle of the incident light will change, especially in the case of a large field of view angle, the incident angle of the light deviates greatly from the parallel light assumption. This change in angle will cause the transmittance and spectral selectivity of the micro-nano structure filter to deviate, thereby affecting the imaging effect.

[0003] Although some micro-nano structure filters currently consider angle dependence and are optimized for different incident angle ranges to correct the effects of angle, because the incident angles of light received by each pixel on a CCD or CMOS sensor are different, even if the filter is optimized for a specific incident angle, it cannot provide ideal transmittance in all pixels. Especially in a large field of view angle, a single angle correction cannot meet the needs of different pixels for light of different incident angles, and existing angle correction methods are difficult to fully adapt to the angle changes of all pixels, especially when the field of view angle is large or the imaging resolution is high. Therefore, a new data correction method for a micro-nano structure spectral camera based on a micro-nano structure filter is needed. SUMMARY

[0004] Based on the shortcomings of the prior art described above, the purpose of the present application is to provide a data correction method and device for a micro-nano structure spectral camera to solve the above technical problems.

[0005] To achieve the above purpose, the present application provides the following technical solution: a data correction method for a micro-nano structure spectral camera, comprising:

[0006] symmetrically divide the half field of view angle of the spectral camera along the main optical axis into a preset number of angle sub-regions, each angle sub-region corresponding to a different incident angle range;

[0007] preprocessing the obtained original spectral data;

[0008] The multiple row image elements corresponding to the same wavelength section in the imaging sensor are divided according to angle sub-regions, so that each angle sub-region corresponds to a group of row image elements, and a mapping relationship between the row image elements and the incident angles is established;

[0009] In the multiple row image elements corresponding to each wavelength section, the micro-nano structure filters adapted to different incident angle ranges are respectively arranged, so that the angle response range of the filter arranged in each row image element matches the incident angle range of the corresponding angle sub-region;

[0010] In the multiple row image elements corresponding to each wavelength section, the image element data whose incident angle falls within the angle response range of the arranged micro-nano structure filter is selected;

[0011] The selected image element data is spliced in row order to generate the correction spectrum data of the wavelength section, and the full-wavelength spectrum correction result is output.

[0012] The present application further provides that the angle width of the angle sub-region is satisfies , the angle width is , the half field angle is , the division parameter is .

[0013] The number of each angle sub-region is numbered in integer multiples of the angle width of the angle sub-region with the main optical axis as the center of symmetry; .

[0014] The image element rows corresponding to each wavelength section on the imaging sensor are mapped in the number order of the angle sub-regions, so that the incident angle received by each image element section and the incident angle range of the corresponding angle sub-region are the same;

[0015] The incident angle range is determined by the angle width of the angle sub-region and the half field angle .

[0016] The present application further provides that the preprocessing includes dark background value deduction processing on each image element in the obtained original spectrum data;

[0017] The image element signal intensity is standardized according to the standard whiteboard reflectivity calibration, and the original signal intensity is converted into a relative spectral response value;

[0018] The standardization coefficient used in the standardization processing is determined based on the reference response value under standard light source irradiation.

[0019] The present application further provides that the micro-nano structure filter is a micro-structure device with directional selective response characteristics, the types of the micro-nano structure filter include photonic crystal filter, sub-wavelength structure filter and super surface filter, and have the following characteristics:

[0020] The micro-nano structure filters of different rows arranged in the same waveband have the same structural center wavelength and correspond to different incident angle response windows respectively.

[0021] The micro-nano structure filter has maximum transmittance in the designed incident angle range, and the center wavelength offset is less than a preset allowable deviation value.

[0022] The application further provides that, in the process of selecting the pixel data, only the pixel data whose incident angle falls within the design angle boundary of the micro-nano structure filter arranged in the row of pixels is selected, and the minimum incident angle and the maximum incident angle of the design angle boundary are the same as the incident angle range of the angle subregion mapped by the row of pixels.

[0023] The application further provides that, the selected pixel data is sequentially spliced according to the row arrangement order from the center of the field of view to the edge, so as to ensure that the center wavelengths of the adjacent row overlap regions are aligned.

[0024] The application further provides that, the division parameters of the angle subregion are The division parameters are set according to the required angle resolution and the incident angle response characteristics of the filter, and satisfy: wherein, is the maximum allowable incident angle of the micro-nano structure filter.

[0025] The application further provides that, the imaging sensor is a CMOS sensor or a CCD sensor, and the relationship between the pixel size and the focal length satisfies: wherein, is the size of a single pixel of the sensor, is the focal length, is a preset minimum angle subregion width.

[0026] The application further provides a data correction device of a micro-nano structure spectral camera, and the device comprises:

[0027] A field of view division module: used for symmetrically and equally dividing a half field of view angle of the spectral camera along a main optical axis direction into a preset number of angle subregions, each angle subregion corresponding to a different incident angle range;

[0028] A spectral preprocessing module: used for preprocessing the obtained original spectral data;

[0029] A pixel mapping module: used for dividing a plurality of row pixels corresponding to the same wavelength band in the imaging sensor according to the angle subregions, so that each angle subregion corresponds to a group of row pixels, and a mapping relationship between the row pixels and the incident angles is established;

[0030] The filter configuration module is configured to configure the micro-nano structure filter adapted to different incident angle ranges in the multiple row image elements corresponding to each wavelength segment, so that the angle response range of the filter configured in each row image element matches the incident angle range of the corresponding angle sub-region;

[0031] The image element screening module is configured to select image element data whose incident angle falls within the angle response range of the configured micro-nano structure filter in the multiple row image elements corresponding to each wavelength segment;

[0032] The spectrum splicing module is configured to splice the selected image element data in sequence to generate corrected spectrum data of the wavelength segment, and output the full-wavelength spectrum correction result.

[0033] The present application provides a kind of micro-nano structure spectrum camera data correction method and device, the method is by the half field angle of spectrum camera along the main optical axis direction symmetry equal division is divided into pre-set number of angle sub-region, each angle sub-region corresponds to a different incident angle range;The original spectrum data obtained is preprocessed;The multiple row image elements corresponding to the same wavelength segment in imaging sensor are divided according to angle sub-region, so that each angle sub-region corresponds a group of row image elements, the mapping relationship between row image element and incident angle is established;In the multiple row image elements corresponding to each wavelength segment, the micro-nano structure filter adapted to different incident angle ranges is configured respectively, so that the angle response range of the filter configured in each row image element matches the incident angle range of the corresponding angle sub-region;In the multiple row image elements corresponding to each wavelength segment, the image element data whose incident angle falls within the angle response range of the configured micro-nano structure filter is selected;The selected image element data is spliced in sequence to generate corrected spectrum data of the wavelength segment, and the full-wavelength spectrum correction result is output, the beneficial effects include:

[0034] 1, realize the accurate image element partitioning based on incident angle mapping: by the half field angle along the main optical axis direction equal division is divided into multiple angle sub-region, and establishes with row image element one-to-one mapping relationship, so that each image element corresponds to a definite incident angle range, provides geometric basis for filter response characteristic matching;

[0035] 2, matching filter configuration: configure the micro-nano structure filter with different incident angle response windows on the row image element corresponding to different angle sub-regions, so that the structure center wavelength remains unchanged, and the high transmissivity of different angle regions is maintained, and the overall spectral consistency is improved;

[0036] 3, angle-guided splicing strategy: the effective data in each angle sub-region is spliced according to the arrangement order of row image element in field of view, so that the reconstructed spectrum data is spatially continuous and physically consistent, which helps to build the real scene spectrum map facing full wavelength.

[0037] The above description is only a summary of the technical solutions of the present application. In order to more clearly understand the technical means of the present application, the following specific embodiments of the present application can be implemented according to the content of the description, and in order to make the above and other purposes, characteristics and advantages of the present application more obvious and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor. In the drawings:

[0039] Figure 1 A flow chart of a data correction method of a micro-nano structure spectral camera is shown for an exemplary embodiment of the present application;

[0040] Figure 2 A structural schematic diagram of a data correction device of a micro-nano structure spectral camera is shown for an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0041] The embodiments of the present application will be described below with reference to the drawings and preferred embodiments, and those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in the present specification. The present application can also be implemented or applied by different specific embodiments, and the details in the present specification can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be understood that the preferred embodiments are only for illustrating the present application, but not for limiting the protection scope of the present application.

[0042] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present application in a schematic manner, and only the components related to the present application are shown in the diagrams, but not the number, shape and size of the components when actually implemented. The actual implementation of each component may be a random change, and the component layout pattern may be more complex.

[0043] In the following description, a large number of details are discussed to provide a more thorough explanation of the embodiments of the present application, however, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details, and in other embodiments, the known structures and devices are shown in the form of block diagrams rather than in the form of details, to avoid making the embodiments of the present application difficult to understand. EMBODIMENTS

[0044] A data correction method of a micro-nano structure spectral camera,Figure 1 The application is shown, comprising:

[0045] The half field angle of the spectral camera is symmetrically divided into a preset number of angle sub-zones along the direction of the main optical axis, and each angle sub-zone corresponds to a different incident angle range;

[0046] The obtained original spectral data is preprocessed;

[0047] The plurality of row image elements corresponding to the same wavelength segment in the imaging sensor are divided according to the angle sub-zone, so that each angle sub-zone corresponds to a group of row image elements, and a mapping relationship between the row image element and the incident angle is established;

[0048] In the plurality of row image elements corresponding to each wavelength segment, the micro-nano structure filter adapted to different incident angle ranges is configured, so that the angle response range of the filter configured for each row image element matches the incident angle range of the corresponding angle sub-zone;

[0049] In the plurality of row image elements corresponding to each wavelength segment, the image element data whose incident angle falls within the angle response range of the configured micro-nano structure filter is selected;

[0050] The selected image element data is spliced in row order to generate the corrected spectral data of the wavelength segment, and the full-wavelength spectral correction result is output.

[0051] The application is further provided, wherein the angle width of the angle sub-zone satisfies , is the angle width, is the half field angle, is the division parameter, and the division step comprises:

[0052] The number of each angle sub-zone is numbered in integer multiples of the angle width of the angle sub-zone with the main optical axis as the symmetric center;

[0053] The image element row corresponding to each wavelength segment on the imaging sensor is mapped according to the numbering order of the angle sub-zone, so that the incident angle received by each image element segment is the same as the incident angle range of the corresponding angle sub-zone;

[0054] The incident angle range is determined by the angle width of the angle sub-zone and the half field angle ; specifically, in the embodiment, the half field angle of the spectral camera is symmetrically divided into a preset number of angle sub-zones along the direction of the main optical axis, the division parameter is , and then angle sub-zones are formed, and the angle width of each angle sub-zone satisfies ​Each angular sub-region is arranged sequentially from the center of the field of view to both sides, with the principal optical axis as the center of symmetry, as shown in the example. For multiple row pixels in the imaging sensor corresponding to the same wavelength band, they are divided into several groups along the direction perpendicular to the principal optical axis, with the number of groups equal to the number of angular sub-regions. Each group of pixels corresponds to one angular sub-region. A mapping relationship between row pixels and incident angles is established, so that the range of incident angles received by each group of pixels corresponds to the angular width of its corresponding angular sub-region. The angle range determined by the numbering is consistent. Through this mapping relationship, different incident light angles correspond to row pixels at different field positions, providing a basis for angle response matching of micro-nano structure filters and angle compensation of spectral data. This angle division and mapping method ensures that the incident angle range can be accurately matched during the correction process, thereby improving the consistency of spectral response and correction accuracy.

[0055] The present invention is further configured such that the preprocessing includes subtracting the dark background value from each pixel in the acquired raw spectral data;

[0056] The pixel signal intensity is standardized according to the standard whiteboard reflectance calibration, and the original signal intensity is converted into a relative spectral response value.

[0057] The standardization coefficients used in the standardization process are determined based on reference response values ​​under standard light source illumination. Specifically, in this embodiment, to ensure high spectral consistency and physical validity of the raw spectral data acquired by the micro-nano structure spectral camera, the raw signal of each pixel is preprocessed. This preprocessing step includes dark background subtraction and standardization. The dark background subtraction step is as follows: dark field acquisition is performed under conditions of complete camera shading, and the signal output value of each pixel under conditions of no incident light is recorded as the device's background noise. For any pixel, the raw signal obtained during normal acquisition is denoted as... The dark background value measured under dark field conditions is denoted as The calculation logic for subtracting the dark background value from the pixel is as follows: The effective signal strength after subtracting the dark background value is the pixel data after subtracting the dark background value. The spatial position of a pixel on a two-dimensional imaging array. For wavelength dimension; dark background subtraction can eliminate baseline interference caused by device thermal noise and circuit bias, improving the accuracy of subsequent normalization; using a standard diffuse white board as a reference reflective surface, such as polytetrafluoroethylene (PTFE), under uniform standard light source conditions, the reference response values ​​of the spectral camera at each pixel are acquired wavelength by wavelength. The standardized coefficients are defined based on the reference response values, and the calculation logic for the standardized coefficients is as follows: The standardized coefficient represents the pixel. At wavelength a relative sensitivity correction factor of each wave band to compensate for the non-uniformity of the response of the system optical channel and the filter at different wave bands; a reference reflectance surface calibration value; the pixel data after deducting the dark background value and the normalization coefficient are normalized by wave band to obtain a relative spectral response value, and the calculation logic of the relative spectral response value is as follows: a relative spectral response value; through the above processing, the spectral response error caused by the angle sensitivity of the filter, the optical error of the imaging system, the sensitivity difference of the pixel, and the like can be effectively eliminated, and the different pixels have a unified spectral response reference under different wavelengths.

[0058] The micro-nano structure filter is a micro-structure device with a direction-selective response characteristic, and the types of the micro-nano structure filter include a photonic crystal filter, a sub-wavelength structure filter and a super surface filter, and have the following characteristics:

[0059] The micro-nano structure filters of different rows arranged in the same wave band have the same structural central wavelength and correspond to different incident angle response windows respectively;

[0060] The micro-nano structure filter has a maximum transmittance in the designed incident angle range, and the central wavelength offset is less than a preset allowable deviation value; specifically, in the embodiment, the micro-nano structure filter adopts a periodic nano pattern structure or a super surface configuration to realize selective transmission of the light signal of a specific wavelength and a specific incident angle, thereby having the direction-selective response characteristic; the types of the filter include but are not limited to the photonic crystal filter, the sub-wavelength structure filter and the super surface filter, and each type of filter can realize the required angle-selective transmission characteristic by adjusting the structural parameters, such as the period, the layer thickness, the refractive index gradient or the surface micro-structure geometry; in actual application, for each row of pixel regions of a specific wave band, although the arranged filter has a unified central wavelength design, the angle response ranges of the filter at different incident angles are different, and therefore the incident light of different angle sub-regions is selectively transmitted; the micro-nano structure filters with the same central wavelength but different incident angle response windows are arranged on each row of pixels in the imaging sensor, so that the filters can realize the maximum transmittance in the designed angle range, and ensure that the light signal in a specific angle range accurately enters the corresponding pixel; further, to ensure the accuracy of the spectral correction, the central wavelength offset of the micro-nano structure filter is controlled in the designed incident angle change range, and the offset value does not exceed a preset allowable deviation value; for example, for a filter with a central wavelength of 550 nm, the central wavelength offset in the incident angle change range of 0-60 degrees is 0.5 nm, and the allowable deviation value is 5 nm. , wherein, ​​​The preset allowable deviation value is according to the spectral resolution requirement of the device; the above design ensures that each filter is sensitive to light in a specified waveband and a specific incident angle range, avoids interference between different angles, and improves the reliability of angle correction and the accuracy of spectral restoration.

[0061] The application is further configured to, in the process of selecting the pixel data, only select the pixel data whose incident angle falls within the design angle boundary of the micro-nano structure filter configured for the row of pixels, the minimum incident angle and the maximum incident angle of the design angle boundary being the same as the incident angle range of the angle sub-region mapped by the row of pixels; specifically, in the implementation process, the incident angle of each row of pixels in the imaging sensor is accurately calculated to determine whether the incident angle of the light received by the pixel falls within the design angle boundary of the micro-nano structure filter configured for the pixel; the design angle boundary is composed of the minimum incident angle and the maximum incident angle, and is consistent with the incident angle range of the angle sub-region mapped by the row of pixels, only the pixel data meeting the condition is retained, and the pixel data exceeding the response range of the filter is removed, so as to ensure that the selected data has the best filter transmission performance and spectral response accuracy; the design angle boundary refers to the optical performance boundary of the micro-nano structure filter optimized for a specific incident angle range; through the above screening step, the effective compensation of the incident angle difference at different field positions is realized, and the correction accuracy and consistency of the spectral data are improved.

[0062] The application is further provided that the selected pixel data is sequentially spliced according to the row arrangement order from the center of the field of view to the edge, so as to ensure the center wavelength alignment of the adjacent row overlapping area; specifically, in the embodiment, the selected pixel data is first sequentially collected according to the row arrangement order from the center of the field of view to the edge based on the spatial arrangement of the imaging sensor; in order to ensure the continuity and consistency of the spliced spectral data, the center wavelength alignment algorithm is used for correction in the overlapping area of the adjacent row pixel data; specifically, the center wavelength difference of the adjacent two rows of filters is calculated, and the spectral response is adjusted by using the interpolation or spectral resampling method to keep the center wavelength consistent; in the correction process, the spectral response of the center area of the field of view is taken as the reference to ensure that the response characteristics of the data in other areas are consistent with the center data; the alignment process effectively eliminates the wavelength shift caused by the angle response difference of the filter, ensures that the spliced spectral data seamlessly connects in the space and wavelength dimensions, and improves the continuity and accuracy of the corrected spectrum; on the basis of the above, in order to further improve the spectral splicing accuracy, the embodiment uses the weighted average method for spectral reconstruction; in the overlapping area, the spectral response intensity and signal quality of the pixel are combined, the overlapping area data is fused by weighted average, the splicing result is optimized, and the spectral distortion caused by the field of view edge effect is reduced; the weighting strategy not only ensures the consistency of the data after splicing in the wavelength, but also avoids the error caused by the response difference of different incident angles; in addition, the adaptive error compensation algorithm is introduced in the embodiment, the spectral response of different areas is analyzed in real time, and dynamic compensation is carried out based on the error model, so as to ensure that the spliced spectral data maintains high accuracy and high consistency in the full wavelength range; the error model comprehensively considers the spectral deviation caused by the field of view edge effect, the angle response difference and the performance change of the micro-nano structure filter; it is assumed that the spectral response of the splicing area is affected by the incident angle change, the filter transmittance and the non-uniformity of the sensor response, based on this assumption, the error model is adjusted in real time by dynamic compensation, and the compensation process includes: analyzing the light incident angle difference of the field of view position of each pixel, comparing the spectral response of the overlapping area, and correcting the response deviation of the field of view edge; according to the incident angle of the pixel and the angle response characteristics of the filter, the transmittance change is calculated and the spectral response is adjusted; combined with the spatial distribution and response characteristics of the imaging sensor, the non-uniformity of the pixel response is evaluated and corrected; through the above dynamic compensation measures, it is ensured that the spliced spectral data meets the design requirements in terms of accuracy and consistency, and the overall performance of the micro-nano structure spectral camera is improved.

[0063] The application is further provided that the division parameter of the angle sub-area According to the required angle resolution and the incident angle response characteristics of the filter, and meet: , wherein, is the maximum allowed incident angle of the micro-nano structure filter; specifically, the division parameter of the angle sub-area The maximum permissible incident angle of the micro / nano structure filter is determined based on the required angular resolution and the incident angle response characteristics of the filter. This means that the filter can maintain its designed optical performance and transmittance within the incident angle range; to ensure that the incident angle range corresponding to each angle sub-region does not exceed the filter's allowable incident angle, thereby avoiding a decrease in filter performance due to the incident angle deviating from the design range, parameters are defined. It should meet the following requirements: ,in, This is a rounding function; during implementation, it is first determined based on the half-field angle of the spectral camera. and the maximum permissible angle of incidence of the filter Calculate the minimum partitioning parameter The field of view is divided into equal parts. Each angle sub-region ensures the angle width of each angle sub-region. The incident angle should not exceed the maximum permissible angle of incidence of the filter. This division allows the change in incident light angle within each angular sub-region to be controlled within the effective response range of the filter, ensuring the optical performance of the micro / nano structure filter and the accuracy of spectral data correction, thereby improving the measurement accuracy and consistency of the entire spectral camera device.

[0064] The present invention is further configured such that the imaging sensor is a CMOS sensor or a CCD sensor, and the relationship between the pixel size and the focal length satisfies: ,in, For the sensor's single pixel size, For focal length, The minimum angle sub-region width is preset; specifically, the imaging sensor can be a CMOS sensor or a CCD sensor, and the pixel size... and lens focal length The relationship between them satisfies the following conditions: This relationship ensures that the viewing angle of each pixel does not exceed its corresponding angular sub-region, thereby avoiding aliasing of light information between different angular sub-regions. Specifically, it is the ratio of pixel size to focal length. The spatial sampling angle of the pixel is determined. Meeting the above conditions ensures that the angular resolution of the imaging sensor is at least not lower than the requirement for the smallest angular sub-region division, improving the accuracy of angle mapping and the precision of spectral correction; if Exceed If the pixel viewing angle is too large, the incident angle information of multiple angle sub-regions will be mixed, reducing the correction effect. Therefore, in this embodiment, by reasonably selecting the sensor pixel size and focal length parameters, spatial sampling conditions that match the minimum angle sub-region width are achieved, thereby effectively supporting the subsequent angle response correction method of micro-nano structure filters based on angle sub-region division. Example

[0065] Referring to Figure 2 The data correction device of the exemplary micro-nano structure spectral camera includes:

[0066] A field of view division module is configured to divide a half field of view angle of the spectral camera symmetrically along a main optical axis direction into a preset number of angle sub-zones, each angle sub-zone corresponding to a different incident angle range.

[0067] A spectral preprocessing module is configured to preprocess the acquired original spectral data.

[0068] A pixel mapping module is configured to divide a plurality of row pixels corresponding to the same wavelength segment in the imaging sensor according to the angle sub-zones, so that each angle sub-zone corresponds to a group of row pixels, and a mapping relationship between the row pixels and the incident angles is established.

[0069] A filter configuration module is configured to configure micro-nano structure filters adapted to different incident angle ranges in the plurality of row pixels corresponding to each wavelength segment, so that the angle response range of the filter configured for each row pixel matches the incident angle range of the corresponding angle sub-zone.

[0070] A pixel screening module is configured to select pixel data of the plurality of row pixels corresponding to each wavelength segment, whose incident angle falls within the angle response range of the configured micro-nano structure filter.

[0071] A spectral splicing module is configured to splice the selected pixel data in row order to generate corrected spectral data of the wavelength segment, and output a full-wavelength spectral correction result.

[0072] It should be noted that the data correction device of the micro-nano structure spectral camera provided by the above embodiment and the data correction method of the micro-nano structure spectral camera provided by the above embodiment belong to the same concept, and the specific manner in which each module and unit performs operations has been described in detail in the method embodiment, which will not be repeated here. The data correction device of the micro-nano structure spectral camera provided by the above embodiment can complete the above-described all or part of the functions by different functional modules according to the needs in actual application, i.e., the internal structure of the system is divided into different functional modules to complete the above-described all or part of the functions, and this is not limited herein.

[0073] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A data correction method of a micro / nano structured spectral camera, characterized in that, The method comprises the following steps: symmetrically and equally divide the half field angle of the spectral camera along the main optical axis direction into a preset number of angle sub-zones, each angle sub-zone corresponding to a different incident angle range; preprocessing the obtained original spectral data; dividing the multiple row image elements corresponding to the same wavelength segment in the imaging sensor according to the angle sub-zone, so that each angle sub-zone corresponds to a group of row image elements, and a mapping relationship between the row image elements and the incident angles is established; in the multiple row image elements corresponding to each wavelength segment, a micro-nano structure filter suitable for different incident angle ranges is configured, so that the angle response range of the filter configured for each row image element matches the incident angle range of the corresponding angle sub-zone; in the multiple row image elements corresponding to each wavelength segment, the image element data whose incident angle falls within the angle response range of the configured micro-nano structure filter is selected; the selected image element data is spliced in row order to generate corrected spectral data of the wavelength segment, and a full wavelength spectral correction result is output.

2. The data correction method of a micro-nano structured spectral camera according to claim 1, characterized in that, an angular width of the angular sub-zone satisfies , is an angular width, is a half field angle, is a division parameter, the division step comprising: The numbering of each angle sub-zone is numbered with the main optical axis as the center of symmetry, and the angle sub-zone is numbered by integer times of the angle width of the angle sub-zone . the row image elements corresponding to each wavelength segment on the imaging sensor are mapped in the order of the angle sub-zone numbers, so that the incident angle received by each image element segment is the same as the incident angle range of the corresponding angle sub-zone; The range of incidence angles is determined by the angular width of the angular sub-zone and the half field of view .

3. The data correction method of a micro-nano structured spectral camera according to claim 1, characterized in that, the preprocessing includes dark background value deduction processing of each image element in the obtained original spectral data; the image element signal intensity is standardized according to the standard whiteboard reflectivity calibration, and the original signal intensity is converted into a relative spectral response value; the standardization coefficient used in the standardization processing is determined based on the reference response value under standard light source irradiation.

4. The data correction method of a micro-nano structured spectral camera according to claim 1, characterized in that, The micro-nano structure filter is a micro-structure device with direction-selective response characteristics, and the types of the micro-nano structure filter include photonic crystal filter, sub-wavelength structure filter and super surface filter, and have the following characteristics: The micro-nano structure filters configured in different rows of the same wavelength segment have the same structure center wavelength and correspond to different incident angle response windows, respectively. The micro-nano structure filter has maximum transmittance within its designed incident angle range, and the center wavelength offset is less than a preset allowable deviation value.

5. The data correction method of a micro-nano structured spectral camera according to claim 1, characterized in that, In the process of selecting the image element data, only the image element data whose incident angle falls within the design angle boundary of the micro-nano structure filter configured for the row image element is selected, and the minimum incident angle and the maximum incident angle of the design angle boundary are the same as the incident angle range of the angle sub-zone mapped by the row image element.

6. The data correction method of a micro-nano structured spectral camera according to claim 1, characterized in that, The selected image element data is spliced in turn according to the row arrangement order from the center of the field of view to the edge, so as to align the center wavelengths of the adjacent row overlapping areas.

7. The data correction method of a micro-nano structured spectral camera according to claim 1, characterized in that, The division parameter of the angle sub-area According to the required angle resolution and the incident angle response characteristics of the filter, it is set and meets: Wherein, The maximum allowed incident angle of the micro-nano structure filter.

8. The data correction method of a micro-nano structured spectral camera according to claim 1, wherein, The imaging sensor is a CMOS sensor or a CCD sensor, and the relationship between the pixel size and the focal length satisfies: wherein, is the sensor single pixel size, is the focal length, is a preset minimum angle sub-region width.

9. A data correction device of a micro / nano structured spectral camera, for implementing the data correction method of the micro / nano structured spectral camera according to any one of claims 1-8, characterized in that, The method comprises the following steps: a field division module for symmetrically and equally dividing the half field angle of the spectral camera along the main optical axis direction into a preset number of angle sub-zones, each angle sub-zone corresponding to a different incident angle range; a spectral preprocessing module for preprocessing the obtained original spectral data; an image element mapping module for dividing the multiple row image elements corresponding to the same wavelength segment in the imaging sensor according to the angle sub-zone, so that each angle sub-zone corresponds to a group of row image elements, and a mapping relationship between the row image elements and the incident angles is established; The filter configuration module is configured to configure the micro-nano structure filter adapted to different incident angle ranges in the multiple row image elements corresponding to each wavelength segment, so that the angle response range of the filter configured in each row image element matches the incident angle range of the corresponding angle sub-region; The image element screening module is configured to select image element data whose incident angle falls within the angle response range of the configured micro-nano structure filter in the multiple row image elements corresponding to each wavelength segment; The spectrum splicing module is configured to splice the selected image element data in sequence to generate the corrected spectrum data of the wavelength segment, and output the full-wavelength spectrum correction result.

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