A spectral imaging method and device based on a scanning galvanometer

Abstract

The present invention relates to the technical field of spectral acquisition, and specifically relates to a spectral imaging method and device based on a scanning galvanometer. Among them, a spectral imaging method based on a scanning galvanometer includes the following steps: S1: Initialize the spectral imaging device; S2: Uniformly irradiate the surface of the target object with a light source; S3: Straighten the light beam reflected from the surface of the target object; S4: Control the light beam to scan along the X-axis direction and the Y-axis direction through a scanning galvanometer group provided in the spectral imaging device; S5: Collect spectral data of the target object through a spectrometer provided in the spectral imaging device. The present invention has a high degree of automation, reduces the dependence on high-performance control equipment, and only needs to control the light beam to scan along the X-axis direction and the Y-axis direction through the scanning galvanometer group provided in the spectral imaging device to achieve spectral data acquisition in the push-broom imaging mode, combining performance and economy, with high acquisition efficiency and good detection performance.

Description

Technical Field

[0001] The present invention relates to the technical field of spectral acquisition, and particularly relates to a spectral imaging method and device based on a scanning galvanometer. Background Art

[0002] A spectrometer is an instrument that analyzes the composition and structure of substances by measuring the absorption, reflection, or emission characteristics of substances for light of different wavelengths. In the prior art, systems based on push-broom line-scanning spectrometers are widely used. Such spectrometers perform line scanning of the detector in the target area, collect spectral data row by row, and then obtain a complete spectral image through stitching. They have high spectral resolution and accuracy, and are suitable for large-scale and high-resolution spectral imaging. However, the structure of such spectrometers is relatively complex, requiring precise mechanical motion systems and high-quality detectors, resulting in high overall costs. At the same time, they are relatively cumbersome to use. For example, a method and device for adjusting an imaging spectrometer disclosed in a Chinese patent (Publication No.: CN111896108B) show a method for adjusting an imaging spectrometer, which can simplify the debugging steps of the spectrometer to a certain extent, but there are still relatively complex operation steps and it is not very convenient to use. At the same time, push-broom line-scanning spectrometers also have the defect of high difficulty in optimizing surface detection, and have not fully solved the contradiction between spatial resolution and spectral resolution, resulting in unsatisfactory effects in some dynamic or real-time applications. In application scenarios for flexible scanning imaging, precise positioning, and efficient data collection for specific areas, existing push-broom scanning spectrometers still have certain limitations, with low acquisition efficiency and poor detection performance. Summary of the Invention

[0003] The technical problem to be solved by the present invention: Existing spectral acquisition methods have many operation steps, are not convenient for debugging, and still have certain limitations in application scenarios for flexible scanning imaging, precise positioning, and efficient data collection for specific areas, with low acquisition efficiency and poor detection performance.

[0004] To solve the above technical problem, the first aspect of the present invention adopts the following technical solution: A spectral imaging method based on a scanning galvanometer, comprising the following steps:

[0005] S1: Initialize the spectral imaging device;

[0006] S2: Place a reference plate and a target object, and uniformly irradiate the surface of the target object with a light source;

[0007] S3: Straighten the light beam reflected from the surface of the target object to obtain a highly directional and parallel light beam;

[0008] S4: Control the light beam to scan along the X-axis direction and the Y-axis direction through the scanning galvanometer group provided in the spectral imaging device to locate and collect the light beam reflected by the target object;

[0009] S5: Focus the light beam and collect the spectral data of the target object generated by the spectrometer provided in the spectral imaging device.

[0010] When the present invention works, it can realize a series of operations such as uniform illumination of the light source, straightening of the light beam, scanning of the light beam along the X-axis direction and the Y-axis direction, focusing of the light beam, and collection and generation of spectral data. It has a high degree of automation, reduces the dependence on high-performance control equipment, and only needs to control the light beam to scan along the X-axis direction and the Y-axis direction through the scanning galvanometer group provided in the spectral imaging device to realize the collection of spectral data in the push-broom imaging mode. It combines performance and economy, has a high collection efficiency and good detection performance.

[0011] Preferably, in the step S1, the following steps are further included:

[0012] A1: Initialize the spectral imaging device and reset the scanning galvanometer group;

[0013] A2: Place the reference plate, irradiate the reference plate with the light source, the scanning galvanometer group acts, and collect the reference plate signal by the spectrometer;

[0014] A3: Adjust the spectrometer control parameters and adjust the maximum value of the reference plate signal intensity to a preset reference value;

[0015] A4: Turn off the light source and block the light, and collect the dark background signal;

[0016] A5: Place the white field, irradiate the white field with the light source, the scanning galvanometer group acts, and collect the white field signal by the spectrometer.

[0017] Preferably, in the step S5, when focusing the light beam and collecting the spectral data of the target object generated by the spectrometer provided in the spectral imaging device, the following steps are adopted:

[0018] B1: Focus the light beam and collect the spectral data of the target object generated by the spectrometer provided in the spectral imaging device to obtain the target object signal and the reference plate signal;

[0019] B2: Perform dark field correction on the collected white field signal, reference plate signal, and target object signal. After obtaining the dark field corrected white field signal, reference plate signal, and target object signal, perform white field correction on the dark field corrected target object signal;

[0020] B3: Perform illumination change with time correction on the white field corrected target object signal and the dark field corrected reference plate signal to obtain the corrected target object signal and the corrected reference plate signal;

[0021] B4: Obtain the reflectivity of the target object by calculating the ratio of the corrected target object signal to the corrected reference plate signal.

[0022] When the present invention works, it can realize a series of operations such as the adaptive adjustment of the reference plate signal, the calibration of the dark background signal and the white field signal, the acquisition of the target object signal, and the calculation of the reflectivity of the target object. At the same time, it measures and compensates for the background noise through black field correction, calibrates the uniformity of the optical signal distribution through white field correction, and dynamically compensates for the errors caused by factors such as equipment aging and environmental temperature changes through the correction of the change of illuminance over time, which can further improve the accuracy of the spectral data, ensure the integrity and consistency of the data during the acquisition process, provide higher flexibility and acquisition efficiency, and are applicable to various working scenarios.

[0023] Preferably, in step B2, after performing black field correction on the collected white field signal, reference plate signal, and target object signal to obtain the black field corrected white field signal, reference plate signal, and target object signal, when performing white field correction on the black field corrected target object signal, the following steps are adopted:

[0024] C1: When performing black field correction on the collected white field signal, reference plate signal, and target object signal to obtain the black field corrected white field signal, reference plate signal, and target object signal, the following formulas are adopted:

[0025] ;

[0026] ;

[0027] ;

[0028] Where: is the white field signal after black field correction;

[0029] is the white field signal before black field correction;

[0030] is the reference plate signal after black field correction;

[0031] is the reference plate signal before black field correction;

[0032] is the target object signal after black field correction;

[0033] is the target object signal before black field correction;

[0034] is the dark background signal;

[0035] is the wavelength dimension;

[0036] is the X-axis coordinate of the target point;

[0037] is the Y-axis coordinate of the target point;

[0038] is the scanning period;

[0039] C2: When performing white-field correction on the target object signal after black-field correction, the following formula is used:

[0040] ;

[0041] Where: is the target object signal after white-field correction;

[0042] In the step B3, when performing illumination change with time correction on the target object signal after white-field correction and the reference plate signal after black-field correction to obtain the corrected target object signal and the corrected reference plate signal, the following formula is used:

[0043] ;

[0044] ;

[0045] Where: is the corrected target object signal;

[0046] is the corrected reference plate signal;

[0047] In the step B4, when obtaining the reflectivity of the target object by calculating the ratio of the corrected target object signal to the corrected reference plate signal, the following formula is used:

[0048] ;

[0049] Where: is the reflectivity of the target object.

[0050] Preferably, in the step S4, when controlling the beam to scan along the X-axis direction and the Y-axis direction through the scanning galvanometer group provided in the spectral imaging device to position and collect the beam reflected by the target object, the following steps are adopted: perform local scanning to obtain a local area matrix, determine the position coordinates of the target area, calculate the angle group for controlling the beam to scan along the X-axis direction and the Y-axis direction, and control the beam to scan row by row and reciprocally along the X-axis direction and the Y-axis direction according to the calculated angle group.

[0051] When the present invention works, global scanning and local scanning can be achieved only by controlling the scanning galvanometer group provided in the spectral imaging device, which greatly reduces the dependence on a precise mechanical motion system and a high-quality detector. It can flexibly scan and image a specific area, facilitating precise positioning, with good detection performance and high scanning flexibility. At the same time, it can avoid the problem of spectral data redundancy caused by global scanning in a specific scenario, improving the time utilization efficiency. Meanwhile, according to the calculated angle group, the control beam scans back and forth row by row along the X-axis direction and the Y-axis direction, which can optimize the scanning path, avoid repeated scanning or missing areas, and further improve the acquisition efficiency of spectral data.

[0052] As a preference, in the step S5, when focusing the beam and collecting the spectral data of the target object through the spectrometer provided in the spectral imaging device, the following steps are adopted: focusing the beam, and collecting the spectral data of the target object through the spectrometer provided in the spectral imaging device to obtain the target object signal and the reference plate signal, and setting the target object signal as , where is the angle for the scanning galvanometer group to control the beam to scan along the X-axis direction, is the angle for the scanning galvanometer group to control the beam to scan along the Y-axis direction.

[0053] To solve the above technical problems, the second aspect of the present invention adopts the following technical solution: A spectral imaging device based on a scanning galvanometer, applying a spectral imaging method based on a scanning galvanometer as described above, includes:

[0054] A light source for uniformly irradiating the surface of the target object;

[0055] An object plane for placing the target object and the corresponding reference plate;

[0056] A semi-transmissive and semi-reflective beam splitter for reflecting the light source beam to vertically irradiate the surface of the target object and allowing the beam reflected by the target object to pass through;

[0057] A collimating lens group for collimating the beam reflected by the target object to keep it parallel;

[0058] A scanning galvanometer group for controlling the beam to scan along the X-axis direction and the Y-axis direction;

[0059] A focusing lens group for focusing the scanned beam onto the beam receiving end of the spectrometer;

[0060] A spectrometer for collecting the spectral signal of the beam and converting it into digital data;

[0061] A main control module for deploying a synchronous control algorithm for overall control, optimizing the scanning path when the scanning galvanometer group performs global or local scanning, and saving data;

[0062] The light source, object plane, semi-transparent and semi-reflective beam splitter, collimating lens group, scanning galvanometer group, focusing lens group and spectrometer are optically connected. The scanning galvanometer group includes an X-direction scanning galvanometer for controlling the beam to scan along the X-axis direction and a Y-direction scanning galvanometer for controlling the beam to scan along the Y-axis direction. Both the scanning galvanometer group and the spectrometer are connected to the main control module for data. Under the synchronous control of the main control module, the scanning galvanometer group and the spectrometer perform two-dimensional coverage scanning acquisition.

[0063] When the present invention works, it can achieve a series of operations such as uniform illumination of the light source, collimation of the light beam, scanning of the light beam along the X-axis and Y-axis directions, focusing of the light beam, and acquisition and generation of spectral data. It has a high degree of automation. Through the optimized control of the continuous deflection characteristics of the scanning galvanometer group, rapid scanning of the target area can be realized. The scanning galvanometer group and the spectrometer perform two-dimensional coverage scanning acquisition under the synchronous control of the main control module, ensuring data integrity and consistency during the scanning process, providing higher flexibility and efficiency for the application scenario, with high acquisition efficiency and good detection performance.

[0064] Preferably, the light source is installed at the starting position of the system optical path. The semi-transparent and semi-reflective beam splitter is arranged obliquely. The center of the semi-transparent and semi-reflective beam splitter is flush with the center of the light source and aligned with the optical axis center of the object plane and the optical axis center of the collimating lens group. The optical axis of the collimating lens group coincides with the optical axis of the light incident end of the scanning galvanometer group, and the optical axis of the focusing lens group coincides with the optical axis of the light output end of the scanning galvanometer group.

[0065] Preferably, a plurality of image points in the imaging part of the spectrometer are set to correspond one by one to a plurality of object points provided on the object plane.

[0066] Preferably, the X-direction scanning galvanometer and the Y-direction scanning galvanometer are optically connected and are respectively arranged at the light incident end and the light output end or the light output end and the light incident end of the scanning galvanometer group.

[0067] The beneficial technical effects of the present invention include:

[0068] 1. The present invention can achieve a series of operations such as uniform illumination of the light source, collimation of the light beam, scanning of the light beam along the X-axis and Y-axis directions, focusing of the light beam, and acquisition and generation of spectral data. It has a high degree of automation and reduces the dependence on high-performance control equipment. By only controlling the light beam to scan along the X-axis and Y-axis directions through the scanning galvanometer group provided in the spectral imaging device, spectral data acquisition in the push-broom imaging mode can be realized, combining performance and economy, with high acquisition efficiency and good detection performance.

[0069] 2. The present invention can achieve a series of operations such as the adaptive adjustment of the reference board signal, the calibration of the dark background signal and the white field signal, the acquisition of the target object signal, and the calculation of the reflectivity of the target object. At the same time, it measures and compensates for background noise through black field correction, calibrates the uniformity of the optical signal distribution through white field correction, and dynamically compensates for errors caused by factors such as equipment aging and environmental temperature changes through illumination change correction over time, which can further improve the accuracy of spectral data, ensure data integrity and consistency during the acquisition process, provide higher flexibility and acquisition efficiency, and is applicable to various working scenarios.

[0070] 3. The present invention can achieve global scanning and local scanning only by controlling the scanning galvanometer group provided in the spectral imaging device, greatly reducing the dependence on a precise mechanical motion system and a high-quality detector. It can achieve flexible scanning imaging of a specific area, facilitating precise positioning, with good detection performance and high scanning flexibility. At the same time, it can avoid the problem of spectral data redundancy caused by global scanning in specific scenarios, improving the time utilization efficiency. At the same time, according to the calculated angle group, it controls the beam to scan back and forth row by row along the X-axis direction and the Y-axis direction, which can optimize the scanning path, avoid repeated scanning or missed areas, and can further improve the acquisition efficiency of spectral data.

[0071] 4. The present invention can achieve a series of operations such as uniform illumination of the light source, straightening of the beam, scanning of the beam along the X-axis direction and the Y-axis direction, focusing of the beam, and acquisition and generation of spectral data. It has a high degree of automation. Through optimized control of the continuous deflection characteristics of the scanning galvanometer group, it can achieve rapid scanning of the target area. Using the scanning galvanometer group and the spectrometer to perform two-dimensional coverage scanning acquisition under the synchronous control of the main control module ensures data integrity and consistency during the scanning process, provides higher flexibility and efficiency for the application scenario, has a high acquisition efficiency, and good detection performance.

[0072] Other features and advantages of the present invention will be disclosed in detail in the following specific embodiments and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] The following further describes the present invention with reference to the drawings:

[0074] Figure 1 It is a flowchart of the working process of a spectral imaging method based on a scanning galvanometer;

[0075] Figure 2 It is a flowchart of the working process of step S1 in a spectral imaging method based on a scanning galvanometer;

[0076] Figure 3 It is a flowchart of the working process of step S5 in a spectral imaging method based on a scanning galvanometer;

[0077] Figure 4 It is a schematic structural diagram of a spectral imaging device based on a scanning galvanometer. Specific implementation mode

[0078] The technical solutions of the embodiments of the present invention will be explained and described below with reference to the accompanying drawings of the embodiments of the present invention. However, the following embodiments are only the preferred embodiments of the present invention, not all of them. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work all fall within the protection scope of the present invention.

[0079] In the following description, terms such as "inner", "outer", "upper", "lower", "left", "right", etc. indicating orientation or position relationship are only for the convenience of describing the embodiments and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the present invention.

[0080] Embodiment 1:

[0081] Please refer to Figure 1 , this embodiment discloses a spectral imaging method based on a scanning galvanometer, including the following steps:

[0082] S1: Initialize the spectral imaging device;

[0083] S2: Place the reference plate and the target object, and evenly irradiate the surface of the target object with the light source 1. Preferably, the wavelength range and light intensity of the light source 1 can also be optimized according to the spectral range of the spectrometer 8, so that it completely covers the spectral range of the spectrometer 8 and can also avoid interference from other factors;

[0084] S3: Straighten the light beam reflected from the surface of the target object to obtain a highly directional and parallel light beam;

[0085] S4: Control the light beam to scan along the X-axis direction and the Y-axis direction through the scanning galvanometer group provided in the spectral imaging device to position and collect the light beam reflected by the target object;

[0086] S5: Focus the light beam, and collect and generate the spectral data of the target object through the spectrometer 8 provided in the spectral imaging device.

[0087] When this embodiment works, it can realize a series of operations such as uniform irradiation of the light source 1, straightening of the light beam, scanning of the light beam along the X-axis direction and the Y-axis direction, focusing of the light beam, and collection and generation of spectral data. It has a high degree of automation and reduces the dependence on high-performance control equipment. Only by controlling the light beam to scan along the X-axis direction and the Y-axis direction through the scanning galvanometer group provided in the spectral imaging device, the spectral data acquisition in the push-broom imaging mode can be realized, with both performance and economy, high acquisition efficiency, and good detection performance.

[0088] Please refer to Figure 2 , in this embodiment, in step S1, the following steps are further included:

[0089] A1: Initialize the spectral imaging device and reset the scanning galvanometer group;

[0090] A2: Place the reference plate, irradiate the reference plate with light source 1, the scanning galvanometer group acts, and the spectrometer 8 collects the reference plate signal;

[0091] A3: Adjust the control parameters of the spectrometer 8, adjust the maximum value of the reference plate signal intensity to a preset reference value. In specific implementation, the preset reference value can be set to 80% to 90% of the saturation value, keep the data validity, and improve the acquisition accuracy;

[0092] A4: Turn off light source 1 and block the light, and collect the dark background signal;

[0093] A5: Place the white field, irradiate the white field with light source 1, the scanning galvanometer group acts, and the spectrometer 8 collects the white field signal.

[0094] Please refer to Figure 3 , preferably, in step S5, when focusing the light beam and collecting the spectral data of the target object through the spectrometer 8 provided in the spectral imaging device, the following steps are adopted:

[0095] B1: Focus the light beam and collect the spectral data of the target object through the spectrometer 8 provided in the spectral imaging device to obtain the target object signal and the reference plate signal;

[0096] B2: Perform black field correction on the collected white field signal, reference plate signal, and target object signal. After obtaining the black field corrected white field signal, reference plate signal, and target object signal, perform white field correction on the black field corrected target object signal;

[0097] B3: Perform illumination change with time correction on the white field corrected target object signal and the black field corrected reference plate signal to obtain the corrected target object signal and the corrected reference plate signal;

[0098] B4: Obtain the reflectivity of the target object by calculating the ratio of the corrected target object signal to the corrected reference plate signal.

[0099] When this example is working, it can achieve a series of operations such as the adaptive adjustment of the reference board signal, the calibration of the dark background signal and the white field signal, the acquisition of the target object signal, and the calculation of the reflectivity of the target object. At the same time, it measures and compensates for the background noise through black field correction, calibrates the uniformity of the optical signal distribution through white field correction, and dynamically compensates for the errors caused by factors such as equipment aging and environmental temperature changes through the correction of illuminance change over time, which can further improve the accuracy of spectral data, ensure the integrity and consistency of the data during the acquisition process, provide higher flexibility and acquisition efficiency, and is applicable to various working scenarios.

[0100] As a further improvement of this embodiment, in step B2, after performing black field correction on the collected white field signal, reference board signal, and target object signal to obtain the white field signal, reference board signal, and target object signal after black field correction, when performing white field correction on the target object signal after black field correction, the following steps are adopted:

[0101] C1: When performing black field correction on the collected white field signal, reference board signal, and target object signal to obtain the white field signal, reference board signal, and target object signal after black field correction, the following formulas are used:

[0102] ;

[0103] ;

[0104] ;

[0105] Where: is the white field signal after black field correction;

[0106] is the white field signal before black field correction;

[0107] is the reference board signal after black field correction;

[0108] is the reference board signal before black field correction;

[0109] is the target object signal after black field correction;

[0110] is the target object signal before black field correction;

[0111] is the dark background signal;

[0112] is the wavelength dimension;

[0113] is the X-axis coordinate of the target point;

[0114] is the Y-axis coordinate of the target point;

[0115] is the scanning period;

[0116] C2: When performing white-field correction on the target object signal after black-field correction, the following formula is used:

[0117] ;

[0118] Where: is the target object signal after white-field correction;

[0119] In the step B3, when performing illumination change correction over time on the target object signal after white-field correction and the reference plate signal after black-field correction to obtain the corrected target object signal and the corrected reference plate signal, the following formula is used:

[0120] ;

[0121] ;

[0122] Where: is the corrected target object signal;

[0123] is the corrected reference plate signal;

[0124] In the step B4, when obtaining the reflectivity of the target object by calculating the ratio of the corrected target object signal to the corrected reference plate signal, the following formula is used:

[0125] ;

[0126] Where: is the reflectivity of the target object.

[0127] In specific implementation, in step S4, when controlling the light beam to scan along the X-axis direction and the Y-axis direction through the scanning galvanometer group provided in the spectral imaging device to locate and collect the light beam reflected by the target object, the following steps are adopted. By performing global scanning through the method of reciprocating line-by-line scanning and serpentine scanning according to the target area, it is possible to avoid repeated scanning or missing areas, effectively reduce the ineffective movement of the scanning galvanometer group, reduce the system operation power consumption and mechanical wear, extend the service life of the device, and improve the stability of the overall scanning process and the consistency of data acquisition.

[0128] Embodiment 2:

[0129] Please refer to Figure 1, this embodiment provides a spectral imaging method based on a scanning galvanometer. The same parts as other embodiments will not be described in detail. The following will elaborate on the differences.

[0130] In this embodiment, in step S4, when controlling the light beam to scan along the X-axis and Y-axis directions through the scanning galvanometer group provided in the spectral imaging device to locate and collect the light beam reflected by the target object, the following steps are adopted for local scanning to obtain the local area matrix, determine the position coordinates of the target area, calculate the angle group for controlling the light beam to scan along the X-axis and Y-axis directions by the scanning galvanometer group, and control the light beam to scan row by row and reciprocally along the X-axis and Y-axis directions according to the calculated angle group.

[0131] When this embodiment works, global scanning and local scanning can be achieved only by controlling the scanning galvanometer group provided in the spectral imaging device, greatly reducing the dependence on a precise mechanical motion system and a high-quality detector. It can flexibly scan and image a specific area, facilitating precise positioning, having good detection performance and high scanning flexibility. At the same time, it can avoid the spectral data redundancy problem caused by global scanning in a specific scenario, improving the time utilization efficiency. Meanwhile, controlling the light beam to scan row by row and reciprocally along the X-axis and Y-axis directions according to the calculated angle group can optimize the scanning path, avoid repeated scanning or missing areas, and further improve the acquisition efficiency of spectral data.

[0132] Preferably, in step S5, when focusing the light beam and collecting the spectral data of the target object through the spectrometer 8 provided in the spectral imaging device, the following steps are adopted: focusing the light beam and collecting the spectral data of the target object through the spectrometer 8 provided in the spectral imaging device to obtain the target object signal and the reference plate signal, and setting the target object signal as , where is the angle for controlling the light beam to scan along the X-axis direction by the scanning galvanometer group, is the angle for controlling the light beam to scan along the Y-axis direction by the scanning galvanometer group, and each group of corresponds to a target point in the target area , and precise acquisition of any target point can be achieved through linkage.

[0133] As a further improvement of this embodiment, when performing local scanning, in step C1, when performing black field correction on the target object signal, the following formula is used:

[0134] ;

[0135] Where: is the target object signal after black field correction;

[0136] In step C2, when performing white-field correction on the target object signal after black-field correction, the following formula is used:

[0137] ;

[0138] where: is the target object signal after white-field correction;

[0139] In step B3, when performing illumination change correction over time on the target object signal after white-field correction and the reference plate signal after black-field correction to obtain the corrected target object signal and the corrected reference plate signal, the following formula is used:

[0140] ;

[0141] where: is the corrected target object signal;

[0142] In step B4, when obtaining the reflectivity of the target object by calculating the ratio of the corrected target object signal to the corrected reference plate signal, the following formula is used:

[0143] ;

[0144] where: is the reflectivity of the target object.

[0145] Preferably, during local scanning, where the local area is input as matrix data, the matrix can be obtained using the physical size-pixel correspondence, or the local area matrix can be obtained using an image combined with a deep learning algorithm. For example, the scanned area is set to 1 and the non-scanned area is set to 0, etc.

[0146] During scanning, obtain the set of angle groups corresponding to the set of regional coordinates, sort them according to the value size, fix one of the angles in, and when scanning from small to large to the boundary according to the other angle after fixing one angle, after changing one angle, scan from large to small according to the other angle, and scan in this cycle to complete the acquisition work, which can optimize the scanning path, reduce the ineffective movement of the scanning galvanometer group, and reduce the system operation power consumption and mechanical wear.

[0147] Example 3:

[0148] This example provides a spectral imaging method based on a scanning galvanometer. The same parts as other examples will not be elaborated, and the differences will be described in detail below.

[0149] In this embodiment, during the scanning operation, in order to be applicable to a drive system with relatively low precision, real-time correction is also required when the scanning galvanometer group operates to complete more accurate spectral acquisition work. In step S4, local scanning is performed to obtain a local area matrix, the position coordinates of the target area are determined, and when calculating the angle group for controlling the beam of the scanning galvanometer group to scan along the X-axis direction and the Y-axis direction, the following calculation formulas are used:

[0150] ;

[0151] where: e is the distance between galvanometers in the scanning galvanometer group, and d is the distance from the axis of the galvanometer in the scanning galvanometer group to the origin of the plane coordinates of the target area;

[0152] In step S4, when controlling the beam to scan row by row along the X-axis direction and the Y-axis direction according to the calculated angle group, the following steps are adopted:

[0153] E1: Perform local scanning to obtain a local area matrix, determine the position coordinates of the target area, calculate the distance from the position coordinates of the target area to the center of the optical axis, and determine the reciprocating scanning direction and the step scanning direction;

[0154] E2: Drive the beam controlled by the scanning galvanometer group to move to the starting position of scanning the target area along the reciprocating scanning direction and the step scanning direction;

[0155] E3: Drive the beam controlled by the scanning galvanometer group to scan to the edge position of the target area along the step scanning direction, and then drive the beam controlled by the scanning galvanometer group to scan to the edge position of the target area along the reciprocating scanning direction to obtain L-shaped spectral data;

[0156] E4: Drive the beam controlled by the scanning galvanometer group to return scan along the reciprocating scanning direction within a unit time to obtain error-corrected spectral data in the reciprocating scanning direction, and obtain the repeatability error in the reciprocating scanning direction by comparing the error-corrected spectral data;

[0157] E5: Drive the beam controlled by the scanning galvanometer group to return scan along the step scanning direction within a unit time to obtain error-corrected spectral data in the step scanning direction, and obtain the repeatability error in the step scanning direction by comparing the error-corrected spectral data;

[0158] E6: Obtain the repeatability error in the reciprocating scanning direction and the repeatability error in the step scanning direction, set a redundant acquisition area, and control the beam to scan row by row along the X-axis direction and the Y-axis direction according to the calculated angle group to obtain spectral data with a comb-shaped edge shape.

[0159] Embodiment 4:

[0160] Please refer to Figure 4, this embodiment provides a spectral imaging device based on a scanning galvanometer, applying a spectral imaging method based on a scanning galvanometer in the above-mentioned embodiment, including:

[0161] A light source 1 for uniformly irradiating the surface of a target object;

[0162] An object plane 2 for placing the target object and a corresponding reference plate;

[0163] A semi-transmissive and semi-reflective beam splitter 3 for reflecting the beam of the light source 1 so that it is perpendicularly irradiated on the surface of the target object, and at the same time allowing the beam reflected by the target object to pass through;

[0164] A collimating lens group 4 for collimating the beam reflected by the target object so that it remains parallel;

[0165] A scanning galvanometer group for controlling the beam to scan along the X-axis direction and the Y-axis direction;

[0166] A focusing lens group 7 for focusing the scanned beam onto the beam receiving end of the spectrometer 8;

[0167] A spectrometer 8 for collecting the spectral signal of the beam and converting it into digital data;

[0168] A main control module 9 for deploying a synchronous control algorithm for overall control, optimizing the scanning path when the scanning galvanometer group scans globally or locally, and saving data;

[0169] The light source 1, the object plane 2, the semi-transmissive and semi-reflective beam splitter 3, the collimating lens group 4, the scanning galvanometer group, the focusing lens group 7 and the spectrometer 8 are optically connected. The scanning galvanometer group includes an X-direction scanning galvanometer 5 for controlling the beam to scan along the X-axis direction and a Y-direction scanning galvanometer 6 for controlling the beam to scan along the Y-axis direction. Both the scanning galvanometer group and the spectrometer 8 are data-connected to the main control module 9, and the scanning galvanometer group and the spectrometer 8 perform two-dimensional coverage scanning acquisition under the synchronous control of the main control module 9.

[0170] When this embodiment works, it can achieve a series of operations such as uniform irradiation of the light source 1, collimation of the beam, scanning of the beam along the X-axis direction and the Y-axis direction, focusing of the beam, and acquisition and generation of spectral data. It has a high degree of automation. Through the optimized control of the continuous deflection characteristics of the scanning galvanometer group, rapid scanning of the target area can be achieved. The scanning galvanometer group and the spectrometer 8 perform two-dimensional coverage scanning acquisition under the synchronous control of the main control module 9, ensuring the data integrity and consistency during the scanning process, providing higher flexibility and efficiency for the application scenario, with high acquisition efficiency and good detection performance.

[0171] Preferably, the light source 1 is installed at the starting position of the optical path of the system. The semi-transmissive and semi-reflective beam splitter 3 is arranged obliquely. The center of the semi-transmissive and semi-reflective beam splitter 3 is flush with the center of the light source 1 and aligned with the optical axis center of the object plane 2 and the optical axis center of the collimating lens group 4. The optical axis of the collimating lens group 4 coincides with the optical axis of the light incident end of the scanning galvanometer group, and the optical axis of the focusing lens group 7 coincides with the optical axis of the light exiting end of the scanning galvanometer group.

[0172] In specific implementation, several image points in the imaging part of the spectrometer 8 are set to correspond one by one to several object points provided on the object plane 2 to achieve correct spectral data acquisition.

[0173] Preferably, the X-direction scanning galvanometer 5 and the Y-direction scanning galvanometer 6 are optically connected and are respectively arranged at the light incident end and the light exiting end or the light exiting end and the light incident end of the scanning galvanometer group. In specific implementation, the scanning galvanometer group further includes an X-direction swing device and a Y-direction swing device. The X-direction scanning galvanometer 5 is installed on the swing part of the X-direction swing device, and the Y-direction scanning galvanometer 6 is installed on the swing part of the Y-direction swing device. Both the X-direction swing device and the Y-direction swing device are data-connected to the main control module 9 to precisely control the angles of the X-direction scanning galvanometer 5 and the Y-direction scanning galvanometer 6.

[0174] As a further improvement of this embodiment, the spectrometer 8 is set as a fiber optic spectrometer 8. Inside the spectrometer 8, there are a collimating lens, a grating spectroscopic system, a focusing lens, and a linear array CCD imaging system to convert the collected spectral signal into digital data and complete the precise measurement of the spectral information of specific points. The main control module 9 includes a main control board and at least one computing power chip.

[0175] Preferably, it further includes an installation housing. The light source 1, the semi-transmissive and semi-reflective beam splitter 3, the object plane 2, the collimating lens group 4, the scanning galvanometer group, the focusing lens group 7, the spectrometer 8, and the main control module 9 are all installed on the installation housing to protect each component and maintain the relative positions of each component.

[0176] The beneficial technical effects of this embodiment include: The present invention can achieve a series of operations such as uniform illumination of the light source, collimation of the light beam, scanning of the light beam along the X-axis direction and the Y-axis direction, focusing of the light beam, and acquisition and generation of spectral data. It has a high degree of automation and reduces the dependence on high-performance control equipment. Only by controlling the light beam to scan along the X-axis direction and the Y-axis direction through the scanning galvanometer group provided in the spectral imaging device, the spectral data acquisition in the push-broom imaging mode can be realized, combining performance and economy, with high acquisition efficiency and good detection performance.

[0177] As described above, it is only the specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that the present invention includes but is not limited to the content described in the drawings and the above specific implementation mode. Any modification that does not deviate from the functional and structural principles of the present invention will be included in the scope of the claims.

Claims

1. A spectral imaging method based on a scanning galvanometer, characterized in that Including the following steps: S1: Initialize the spectral imaging device; In the step S1, the following steps are further included: A1: Initialize the spectral imaging device and reset the scanning galvanometer group; A2: Place the reference plate, irradiate the reference plate with the light source (1), operate the scanning galvanometer group, and collect the reference plate signal by the spectrometer (8); A3: Adjust the control parameters of the spectrometer (8) to adjust the maximum value of the reference plate signal intensity to a preset reference value; A4: Turn off the light source (1) and block the light, and collect the dark background signal; A5: Place the white field, irradiate the white field with the light source (1), operate the scanning galvanometer group, and collect the white field signal by the spectrometer (8); S2: Place the reference plate and the target object, and uniformly irradiate the surface of the target object with the light source (1); S3: Straighten the light beam reflected from the surface of the target object to obtain a highly directional and parallel light beam; S4: Control the light beam to scan along the X-axis direction and the Y-axis direction through the scanning galvanometer group provided in the spectral imaging device to locate and collect the light beam reflected by the target object; In the step S4, when controlling the light beam to scan along the X-axis direction and the Y-axis direction through the scanning galvanometer group provided in the spectral imaging device to locate and collect the light beam reflected by the target object, the following steps are adopted for local scanning to obtain a local area matrix, determine the position coordinates of the target area, calculate the angle group for controlling the light beam to scan along the X-axis direction and the Y-axis direction by the scanning galvanometer group, and control the light beam to scan row by row and reciprocally along the X-axis direction and the Y-axis direction according to the calculated angle group; In the step S4, when performing local scanning to obtain a local area matrix, determine the position coordinates of the target area, and calculate the angle group for controlling the light beam to scan along the X-axis direction and the Y-axis direction by the scanning galvanometer group, the following calculation formula is adopted: ； Wherein: is the angle for the scanning galvanometer group to control the beam to scan along the X-axis direction, is the angle for the scanning galvanometer group to control the beam to scan along the Y-axis direction, is the X-axis coordinate of the target point, is the Y-axis coordinate of the target point, e is the distance between galvanometers in the scanning galvanometer group, and d is the distance from the axis of the galvanometer in the scanning galvanometer group to the origin of the plane coordinates of the target area; In the step S4, when controlling the light beam to scan row by row and reciprocally along the X-axis direction and the Y-axis direction according to the calculated angle group, the following steps are adopted: E1: Perform local scanning to obtain a local area matrix, determine the position coordinates of the target area, calculate the distance from the position coordinates of the target area to the optical axis center, and determine the reciprocating scanning direction and the step scanning direction; E2: Drive the scanning galvanometer group to control the light beam to move to the scanning starting position of the target area along the reciprocating scanning direction and the step scanning direction; E3: After driving the scanning galvanometer group to control the light beam to scan to the edge position of the target area along the step scanning direction, drive the scanning galvanometer group to control the light beam to scan to the edge position of the target area along the reciprocating scanning direction to obtain L-shaped spectral data; E4: Drive the scanning galvanometer group to control the light beam to perform a return scan along the reciprocating scanning direction within a unit time to obtain error-corrected spectral data in the reciprocating scanning direction, and obtain the repeatability error in the reciprocating scanning direction by comparing the error-corrected spectral data; E5: Drive the scanning galvanometer group to control the light beam to perform a return scan along the step scanning direction within a unit time to obtain error-corrected spectral data in the step scanning direction, and obtain the repeatability error in the step scanning direction by comparing the error-corrected spectral data; E6: Obtain the repeatability error in the reciprocating scanning direction and the repeatability error in the step scanning direction, set the redundant acquisition area, and control the beam to reciprocate line by line along the X-axis direction and the Y-axis direction according to the calculated angle group to obtain spectral data with a comb-shaped edge shape; S5: Focus the beam and collect and generate spectral data of the target object through the spectrometer (8) provided in the spectral imaging device; In the step S5, when focusing the beam and collecting and generating spectral data of the target object through the spectrometer (8) provided in the spectral imaging device, the following steps are adopted. After performing black field correction, white field correction, and illumination change correction over time on the target object signal based on the collected white field signal and dark background signal, and performing black field correction and illumination change correction over time on the reference plate signal, calculate and output the reflectivity of the target object.

2. The spectral imaging method based on a scanning galvanometer according to claim 1, wherein: In the step S5, when focusing the beam and collecting and generating spectral data of the target object through the spectrometer (8) provided in the spectral imaging device, the following steps are adopted: B1: Focus the beam and collect and generate spectral data of the target object through the spectrometer (8) provided in the spectral imaging device to obtain the target object signal and the reference plate signal; B2: Perform black field correction on the collected white field signal, reference plate signal, and target object signal to obtain the black field-corrected white field signal, reference plate signal, and target object signal, and then perform white field correction on the black field-corrected target object signal; B3: Perform illumination change correction over time on the white field-corrected target object signal and the black field-corrected reference plate signal to obtain the corrected target object signal and the corrected reference plate signal; B4: Obtain the reflectivity of the target object by calculating the ratio of the corrected target object signal to the corrected reference plate signal.

3. The spectral imaging method based on a scanning galvanometer according to claim 2, characterized in that: In the step B2, when performing black field correction on the collected white field signal, reference plate signal, and target object signal to obtain the black field-corrected white field signal, reference plate signal, and target object signal, and then performing white field correction on the black field-corrected target object signal, the following steps are adopted: C1: When performing black field correction on the collected white field signal, reference plate signal, and target object signal to obtain the black field-corrected white field signal, reference plate signal, and target object signal, the following formula is used: ； ； ； Wherein: is the white field signal after black field correction; is the white field signal before black field correction; is the reference board signal after black field correction; is the reference board signal before black field correction; is the target object signal after black field correction; is the target object signal before black field correction; is the dark background signal; is the wavelength dimension; is the scan cycle; C2: When performing white field correction on the black field-corrected target object signal, the following formula is used: ； Wherein: is the target object signal after white field correction; In the step B3, when performing illumination change correction over time on the white field-corrected target object signal and the black field-corrected reference plate signal to obtain the corrected target object signal and the corrected reference plate signal, the following formula is used: ； ； Wherein: is the target object signal after correction; is the corrected reference board signal; In the step B4, when obtaining the reflectivity of the target object by calculating the ratio of the corrected target object signal to the corrected reference plate signal, the following formula is used: ； Wherein: is the reflectivity of the target object.

4. A spectral imaging method based on a scanning galvanometer according to claim 1, characterized in that: In the step S5, when focusing the light beam and collecting the spectral data of the target object through the spectrometer (8) provided in the spectral imaging device, the following steps are adopted: focusing the light beam, collecting the spectral data of the target object through the spectrometer (8) provided in the spectral imaging device, obtaining the target object signal and the reference plate signal, and setting the target object signal as , where is the wavelength dimension, is the scanning period.

5. A spectral imaging device based on a scanning galvanometer, applying a spectral imaging method based on a scanning galvanometer according to any one of claims 1 to 4, characterized in that, Including: A light source (1) for uniformly irradiating the surface of the target object; An object plane (2) for placing the target object and the corresponding reference plate; A semi-transmissive and semi-reflective beam splitter (3) for reflecting the beam of the light source (1) so that it perpendicularly irradiates the surface of the target object and allowing the beam reflected by the target object to pass through; A collimating lens group (4) for collimating the light beam reflected by the target object to keep it parallel; A scanning galvanometer group for controlling the light beam to scan along the X-axis direction and the Y-axis direction; A focusing lens group (7) for focusing the scanned light beam onto the light beam receiving end of the spectrometer (8); A spectrometer (8) for collecting the spectral signal of the light beam and converting it into digital data; A main control module (9) for deploying a synchronous control algorithm for overall control, optimizing the scanning path during global or local scanning of the scanning galvanometer group, and saving data; The light source (1), the object plane (2), the semi-transparent and semi-reflective beam splitter (3), the collimating lens group (4), the scanning galvanometer group, the focusing lens group (7) and the spectrometer (8) are optically connected. The scanning galvanometer group includes an X-direction scanning galvanometer (5) for controlling the light beam to scan along the X-axis direction and a Y-direction scanning galvanometer (6) for controlling the light beam to scan along the Y-axis direction. Both the scanning galvanometer group and the spectrometer (8) are data-connected to the main control module (9), and the scanning galvanometer group and the spectrometer (8) perform two-dimensional coverage scanning acquisition under the synchronous control of the main control module (9).

6. The spectral imaging device based on a scanning galvanometer according to claim 5, characterized in that: The light source (1) is installed at the starting position of the system optical path. The semi-transparent and semi-reflective beam splitter (3) is arranged obliquely. The center of the semi-transparent and semi-reflective beam splitter (3) is flush with the center of the light source (1) and aligned with the optical axis center of the object plane (2) and the optical axis center of the collimating lens group (4). The optical axis of the collimating lens group (4) coincides with the optical axis of the light incident end of the scanning galvanometer group. The optical axis of the focusing lens group (7) coincides with the optical axis of the light output end of the scanning galvanometer group.

7. The spectral imaging device based on a scanning galvanometer according to claim 5, wherein: A number of image points in the imaging part of the spectrometer (8) are set to correspond one-to-one to a number of object points provided on the object plane (2).

8. The spectral imaging device based on a scanning galvanometer according to claim 5, wherein: The X-direction scanning galvanometer (5) and the Y-direction scanning galvanometer (6) are optically connected and are respectively arranged at the light incident end and the light output end or the light output end and the light incident end of the scanning galvanometer group.

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