Perovskite film laser cutting positioning method

Abstract

The invention discloses a perovskite thin film laser cutting positioning method, which relates to the technical field of laser cutting positioning, and comprises the following steps: flatly fixing a perovskite thin film sample on a laser cutting platform; scanning the surface of the uncut perovskite thin film by using a spectrometer, recording spectral reflectivity distribution of each region, and generating a spectral feature reference map of the uncut perovskite thin film based on spectral reflectivity data; starting a laser cutter to cut the perovskite thin film, and acquiring spectral reflectivity data of a cut area on the surface of the perovskite thin film and the periphery of the cut area by using a spectrometer; carrying out comparison calculation on the spectral reflectivity data and the spectral feature reference map, identifying the spectral difference between the cutting region and the non-cutting region, and generating a spectral difference map; the offset of the laser cutter is calculated, and the cutting path is dynamically adjusted according to the offset; after cutting is completed, quality detection is conducted, a final perovskite thin film sample and cutting data are output, and after cutting is completed, the surface of the perovskite thin film is scanned again.

Description

Technical Field

[0001] The present invention relates to the technical field of laser cutting positioning, and in particular to a method for laser cutting and positioning of perovskite thin films. Background Art

[0002] As a new type of optoelectronic functional material, perovskite materials have been widely used in the fields of solar cells, photodetectors, and light-emitting diodes due to their excellent optoelectronic properties and low-cost preparation process. Among them, the photoelectric conversion efficiency of perovskite solar cells has rapidly increased from about 3.8% to more than 25% in the past decade, approaching the efficiency limit of crystalline silicon solar cells. As the core functional layer, the preparation quality of perovskite thin films directly determines the performance of the devices. During large-area preparation and device packaging, perovskite thin film cutting is a key step for industrial application. Laser cutting technology has become the mainstream technology due to its high precision, non-contact nature, and adaptability to various materials. However, due to the complex optical properties of perovskite thin films themselves, they are easily affected by factors such as laser energy distribution, uneven thickness of perovskite thin films, and processing path deviation during laser cutting, resulting in unstable cutting quality or even functional failure. These problems seriously limit the large-scale application of perovskite materials and device production.

[0003] Existing perovskite thin film laser cutting technologies usually rely on mechanical positioning and preset paths for operation, but lack the ability of real-time feedback and dynamic adjustment to the changes in the optical properties of perovskite thin films. This traditional method has multiple problems. For example, it is difficult to match the cutting accuracy with the optical properties of perovskite thin films, which easily causes the cutting area to shift; the spectral changes during the cutting process are not monitored in real time, making it difficult to identify the quality problems at the cutting edge; and only microscopic images or geometric parameters are relied on for detection after cutting, making it difficult to efficiently evaluate the performance of perovskite thin films. In the processing of large-area perovskite thin films, the unevenness of the optical properties of perovskite thin films and the complexity of material behavior further exacerbate the difficulty of cutting accuracy control, thereby reducing the utilization rate of perovskite thin films and the yield of devices, and restricting the industrial development of perovskite technology. Summary of the Invention

[0004] In view of the above existing problems, the present invention is proposed.

[0005] Therefore, the present invention provides a method for laser cutting and positioning of perovskite thin films to solve the problem that existing perovskite thin film laser cutting technologies usually rely on mechanical positioning and preset paths for operation, but lack the ability of real-time feedback and dynamic adjustment to the changes in the optical properties of perovskite thin films.

[0006] To solve the above technical problems, the present invention provides the following technical solutions: In a first aspect, the present invention provides a method for laser cutting and positioning of perovskite thin films, which includes fixing a perovskite thin film sample flat on a laser cutting platform; Scanning the surface of the uncut perovskite thin film using a spectrometer, recording the spectral reflectance distribution of each region, and generating a spectral feature reference map of the uncut perovskite thin film based on the spectral reflectance data; Starting the laser cutter to cut the perovskite thin film, and collecting the spectral reflectance data of the cutting area and its surroundings on the surface of the perovskite thin film using a spectrometer; Comparing and calculating the spectral reflectance data with the spectral feature reference map, identifying the spectral differences between the cut area and the uncut area, and generating a spectral difference map; According to the spectral difference map, calculating the offset of the laser cutter, and dynamically adjusting the cutting path according to the offset; After cutting, perform quality inspection, output the final perovskite thin film sample and cutting data. After cutting, scan the surface of the perovskite thin film again to generate the final spectral reflectance data; Comparing the final spectral reflectance data with the spectral reference reflectance value to confirm whether the cutting area completely covers the target path. When there is a cutting deviation, restart the device for supplementary cutting.

[0007] As a preferred embodiment of the method for laser cutting and positioning of perovskite thin films according to the present invention, wherein: the step of fixing the perovskite thin film sample flat on the laser cutting platform is as follows: Using the electrostatic adsorption fixing method, firmly adsorbing the perovskite thin film on the platform; Calculating the electrostatic adsorption force between the perovskite thin film and the surface of the control platform, and judging whether the perovskite thin film is firmly adsorbed; Setting an adsorption force threshold, and when the adsorption force is insufficient, readjusting the potential difference and contact area; Using an optical microscope to verify whether the laser focus is located at the center layer of the perovskite thin film surface; When the distance from the laser focus to the perovskite thin film fixing platform is equal to the thickness of the perovskite thin film it indicates that the laser focus is located on the perovskite thin film surface; When the distance from the laser focus to the perovskite thin film fixing platform is greater than or less than the thickness of the perovskite thin film it indicates that the laser focus is offset, and readjust the focal length parameter.

[0008] As a preferred embodiment of the perovskite thin film laser cutting and positioning method of the present invention, the steps are as follows: scanning the surface of the uncut perovskite thin film using a spectrometer, recording the spectral reflectance distribution of each region, and generating a spectral feature reference map of the uncut perovskite thin film. The specific steps are as follows: Divide the surface of the perovskite thin film into grid regions, and respectively represent the number of divisions of the grid regions on the surface of the perovskite thin film in the horizontal and vertical directions. Each grid region corresponds to a sampling point, and the spectral reflectance of each sampling point represents the spectral reflectance of the sampling point on the surface of the perovskite thin film when the wavelength is . Among them, correspond to the abscissa and ordinate of the sampling point in space; Integrate the spectral reflectance distribution of each sampling point, calculate its normalized spectral reflectance, and the spectral reflectance formula is: ; Among them, represents the normalized spectral reflectance at the sampling point , represents the shortest wavelength, represents the longest wavelength, represents the weight function at the wavelength , represents the integral of the infinitesimal change; Map the normalized spectral reflectance data to a two-dimensional matrix to generate a spectral feature reference map of the uncut perovskite thin film; Store the collected spectral reflectance data and the reference map as a two-dimensional matrix file.

[0009] As a preferred embodiment of the perovskite thin film laser cutting and positioning method of the present invention, the steps are as follows: starting the laser cutter to cut the perovskite thin film, and using a spectrometer to collect the spectral reflectance data of the cutting area and its surrounding area on the surface of the perovskite thin film. The specific steps are as follows: The laser cutter starts the cutting work according to the preset target path, During cutting, continuously collect the spectral reflectance data of the cutting area and its surrounding area through a spectrometer, and record the spectral reflectance curve of each sampling point over time.

[0010] As a preferred embodiment of the perovskite thin film laser cutting and positioning method of the present invention, the steps are as follows: comparing and calculating the spectral reflectance data with the spectral feature reference map, identifying the spectral differences between the cutting area and the uncut area, and generating a spectral difference map. The specific steps are as follows: Calculate the change of spectral reflectance at each sampling point over time to obtain the spectral reflectance change rate, and the expression is: ; where, represents the normalized spectral reflectance change rate of the sampling point at time , represents the spectral reference reflectance value of the sampling point on the surface of the uncut perovskite film, represents at wavelength , the spectral reflectance of a certain sampling point on the surface of the perovskite film at time ; Map the spectral reflectance change rates of all sampling points into a two-dimensional matrix to generate a spectral difference map; Set a change threshold T1. When > T1, it indicates that this area is the cut area; when ≤ T1, it indicates that this area is the uncut area.

[0011] As a preferred solution of the perovskite film laser cutting positioning method described in the present invention, wherein: according to the spectral difference map, calculate the offset of the laser cutter and dynamically adjust the cutting path according to the offset. The specific steps are as follows: Compare the spectral difference map with the target cutting path to determine the offset between the actual position of the cutter and the target path. The calculation formula for the offset is: ; where, represents the offset calculated by the laser cutter at the sampling point coordinates , represents the th sampling point at time normalized spectral reflectance change rate, represents the index variable of the sampling point, represents the total number of sampling points, represents the th sampling point to the vertical distance of the target cutting path; When is a positive number, the laser cutting path is biased towards the uncut area and moves towards the uncut area; When is a negative number, the laser cutting path is biased towards the cut area and adjusts into the cut area; When When it is zero, the laser cutting path is accurately located on the target path and no adjustment is required; According to the offset , dynamically adjust the laser cutting path to make it return to the target path and continue the cutting operation; After cutting is completed, record the spectral reflectance change rate of all sampling points and the cutting path data. Based on these data, generate a spectral reflectance change characteristic diagram of the cutting area.

[0012] As a preferred solution of the perovskite thin film laser cutting and positioning method described in the present invention, wherein: after the cutting is completed, quality inspection is performed, and the final perovskite thin film sample and cutting data are output. After the cutting is completed, the surface of the perovskite thin film is scanned again to generate the final spectral reflectance data. The specific steps are as follows: After the laser cutting is completed, use a spectrometer to perform a full-coverage scan of the surface of the perovskite thin film, collect the spectral reflectance data of each grid area, and obtain the final spectral reflectance data , and after collecting the spectral reflectance data of each grid area, obtain the final spectral reflectance distribution diagram.

[0013] As a preferred solution of the perovskite thin film laser cutting and positioning method described in the present invention, wherein: compare the final spectral reflectance data with the spectral reference reflectance value to confirm whether the cutting area completely covers the target path. When there is a cutting deviation, restart the device for supplementary cutting. The specific steps are as follows: According to the final spectral reflectance data and the spectral reference reflectance value , calculate the deviation value, and then substitute the deviation value into the spectral reflectance formula to obtain the spectral reflectance deviation ; When the spectral reflectance deviation is zero, it means that the cutting area completely covers the target path and the cutting is accurate; When the spectral reflectance deviation is greater than zero, it means that there is a spectral deviation and the cutting is offset; Map the spectral reflectance deviation of all sampling points into a two-dimensional matrix to generate a spectral deviation distribution diagram; Set the deviation threshold T2; When ≤T2, it is considered that the cutting area is within the target path range and the cutting is correct; When >T2, it is identified as a cutting deviation area; For the identified cutting deviation area, calculate the supplementary cutting path based on the spectral deviation distribution diagram to obtain the sampling points in the supplementary cutting path The offset, and the device is started according to the offset for supplementary cutting.

[0014] In a second aspect, the present invention provides a computer device, including a memory and a processor, where the memory stores a computer program, and: when the computer program is executed by the processor, any step of the perovskite thin film laser cutting and positioning method described in the first aspect of the present invention is implemented.

[0015] In a third aspect, the present invention provides a computer-readable storage medium, on which a computer program is stored, and: when the computer program is executed by the processor, any step of the perovskite thin film laser cutting and positioning method described in the first aspect of the present invention is implemented.

[0016] The beneficial effects of the present invention are as follows: by introducing spectral reflectivity data into the cutting and positioning and quality detection processes, and combining a spectrometer and a laser cutter to achieve dynamic feedback and adjustment, the present invention generates a spectral feature reference map of the uncut perovskite thin film, monitors the change of spectral reflectivity during the cutting process of the perovskite thin film in real time, generates a spectral difference map, and dynamically adjusts the laser cutting path accordingly, thereby significantly improving the cutting accuracy and quality. In addition, after cutting is completed, the present invention comprehensively evaluates the cutting quality of the perovskite thin film by using comparative analysis of spectral reflectivity, and performs supplementary cutting operations when necessary to ensure that the cutting area completely covers the target path, overcoming the defect of insufficient cutting quality detection means in the prior art. Therefore, the present invention solves the problems of cutting path deviation, insufficient cutting accuracy, and incomplete quality detection in the existing perovskite thin film laser cutting technology. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 It is a flowchart of the perovskite thin film laser cutting and positioning method in Embodiment 1.

[0019] Figure 2 It is a schematic diagram of the spectral difference map in Embodiment 1. Detailed Embodiments

[0020] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following will make a detailed description of the specific embodiments of the present invention in conjunction with the drawings in the specification.

[0021] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention may be practiced in other ways than those specifically described herein. Those skilled in the art can make similar generalizations without departing from the spirit of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0022] Secondly, as used herein, an "embodiment" or "embodiments" refer to specific features, structures, or characteristics that may be included in at least one implementation of the present invention. The phrase "in an embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0023] Example 1, referring to Figure 1 and Figure 2 , is the first embodiment of the present invention. This embodiment provides a method for laser cutting and positioning of perovskite thin films, including the following steps: S1. Fix the perovskite thin film sample flat on the laser cutting platform; Using the electrostatic adsorption fixation method, a uniform electrostatic field is formed on the surface of the laser cutting platform to firmly adsorb the perovskite thin film on the platform; The advantages of the electrostatic adsorption method are as follows: avoiding physical damage to the edges of the perovskite thin film by mechanical clamps; ensuring the surface flatness of the perovskite thin film and reducing the laser focal length deviation caused by surface unevenness; improving the stability of the perovskite thin film during the cutting process and avoiding vibration or sliding; The method for generating electrostatic adsorption is to control the potential difference on the platform surface to form an adsorption force matching the surface material of the perovskite thin film, calculate the electrostatic adsorption force between the perovskite thin film and the platform surface, and determine whether the perovskite thin film is firmly adsorbed. The electrostatic adsorption force The calculation formula is: ; Where represents the relative permittivity of the perovskite thin film material, represents the vacuum permittivity, represents the contact area between the perovskite thin film and the platform, represents the potential difference, represents the distance between the perovskite thin film and the platform; represents the magnitude of the electrostatic adsorption force, with a positive value range and a unit of Newton. Its magnitude directly determines the fixing strength of the perovskite thin film; Set an adsorption force threshold. When the adsorption force is insufficient, readjust the potential difference and contact area; Use an optical microscope to verify whether the laser focus is located at the center layer of the perovskite thin film surface; When the distance from the laser focus to the perovskite thin film fixing platform is equal to the perovskite thin film thickness , it indicates that the laser focus is on the surface of the perovskite thin film; When the distance from the laser focus to the fixed platform of the perovskite thin film is greater than or less than the perovskite thin film thickness , it indicates that the laser focus is offset. Readjust the focal length parameter, and the adjustment formula is: ; Among them, represents the refractive index of the perovskite thin film material, represents the numerical aperture of the laser.

[0024] S2. Use a spectrometer to scan the surface of the uncut perovskite thin film, record the spectral reflectance distribution of each region, and generate a spectral feature reference map of the uncut perovskite thin film based on the spectral reflectance data; Use a standard white light reflector to calibrate the spectrometer to ensure that the spectrometer can accurately collect the spectral reflectance of different regions on the surface of the perovskite thin film; Set the scanning wavelength range of the spectrometer to 300 nm to 800 nm to cover the absorption and reflection spectral ranges of the perovskite material; Set the sampling interval of the spectrometer to 0.01 mm to ensure sufficient spatial resolution while considering the scanning efficiency; Select the high-sensitivity mode to ensure that the spectral reflectance curve can still be reliably recorded in the case of small optical differences on the surface of the perovskite thin film; The spectral characteristics of the perovskite thin film have obvious reflectance changes in the wavelength range of 300 nm to 800 nm, which covers the key part of its optical bandgap and helps to generate a high-precision spectral feature reference map in the follow-up; Divide the surface of the perovskite thin film into grid regions, and respectively represent the number of divisions of the grid regions on the surface of the perovskite thin film in the horizontal ([[]]END]] direction) and vertical ([[]]END]] direction). Each grid region corresponds to a sampling point, and the spectral reflectance of each sampling point , represents the spectral reflectance of the sampling point on the surface of the perovskite thin film when the wavelength is . Among them, correspond to the abscissa and ordinate of the sampling point in space; Integrate the spectral reflectance distribution of each sampling point to calculate its normalized spectral reflectance. The spectral reflectance formula is: ; Among them, represents the normalized value at the sampling point The spectral reflectance, represents the shortest wavelength, represents the longest wavelength, represents the wavelength of the weight function below, represents the integral of the infinitesimal change; The value range of is [0,1], representing the strength of the normalized spectral reflectance: When is 1, it indicates that the reflectance in this area is relatively high; When is 0, it indicates that the reflectance in this area is relatively low; The wavelength of the weight function below , and the calculation formula is: ; Among them, represents the base of the natural logarithm, represents the central wavelength of the optical band gap, represents the square of the standard deviation of the weight distribution; Map the normalized spectral reflectance data to a two-dimensional matrix to generate a spectral feature reference map of the uncut perovskite film; Store the collected spectral reflectance data and the reference map as a two-dimensional matrix file; The accuracy of the reference map is determined by the scanning resolution and the wavelength resolution. The reference map is a spatial distribution map of the surface optical properties of the perovskite film.

[0025] S3. Start the laser cutter to cut the perovskite film, and use a spectrometer to collect the spectral reflectance data of the cut area and its surroundings on the surface of the perovskite film; The laser cutter starts the cutting work according to the preset target path (such as the cutting path designed by CAD), and at the same time starts to monitor the spectral reflectance data of the cutting area and its surroundings in real time. The laser working parameters (such as power, focal length, cutting speed) need to be adjusted according to the material properties and thickness of the perovskite film to ensure that the laser energy is sufficient to penetrate the perovskite film, while avoiding edge thermal damage caused by excessive heat diffusion; During cutting, continuously collect the spectral reflectance data of the cutting area and its surroundings through a spectrometer. The scanning range of the spectrometer is the uncut area along the cutting path and around the cutting area. The scanning frequency needs to be synchronized with the laser cutting speed. For each sampling point, record its spectral reflectance curve changing with time; Collect spectral reflectance data: Collecting spectral reflectance data of the cutting area and its surroundings through a spectrometer is one of the core creative points of the present invention. Different from the cutting methods relying on mechanical positioning in the prior art, the present invention uses spectral data as the basis for adjusting the cutting path, and has the following beneficial effects: Monitor the cutting quality in real time: During the cutting process, the spectral reflectance data can reflect whether the cutting is completely penetrated, whether there are uncut areas or edge thermal damage. By analyzing the spectral differences between the cut area and the uncut area, the laser path can be dynamically adjusted to avoid cutting deviation; Synchronize the cutting speed and the sampling frequency: The present invention emphasizes that the scanning frequency of the spectrometer needs to be synchronized with the cutting speed to ensure that the spectral reflectance changes at the sampling points can accurately reflect the real-time cutting state. In the traditional technology, cutting and detection are often separated, while the present invention realizes the synchronization of cutting and detection, and this design significantly improves the cutting accuracy and efficiency; The present invention particularly mentions that for each sampling point, the change curve of its spectral reflectance over time is recorded. This design solves the problem in the prior art that the optical property changes during the cutting process cannot be dynamically evaluated. For example, in the edge area of cutting the perovskite thin film, the spectral reflectance change curve can be used to judge whether the cutting is complete, whether the edge is damaged, and whether the path is deviated. This time-resolved spectral data analysis method provides a scientific basis for subsequent path adjustment and quality assessment.

[0026] S4. Compare and calculate the spectral reflectance data with the spectral feature reference map, identify the spectral differences between the cut area and the uncut area, and generate a spectral difference map; Calculate the change of the spectral reflectance of each sampling point over time to obtain the spectral reflectance change rate. The expression is: ; Among them, represents the normalized spectral reflectance change rate of the sampling point at time , represents the spectral reference reflectance value of the sampling point on the surface of the uncut perovskite thin film, represents at wavelength , the spectral reflectance of a certain sampling point on the surface of the perovskite thin film at time ; The calculation formula of the spectral reflectance change rate covers a specific wavelength range in integral form. By comparing with the reference reflectance, the spectral change characteristics of the cut area are extracted. This design can accurately reflect the dynamic spectral changes in the local area during the cutting process; Traditional cutting detection methods usually rely only on single-point detection or fixed-wavelength monitoring, making it difficult to comprehensively reflect the spectral changes in the cutting area. Through the introduction of integral calculation and weight function, the present invention achieves spectral change analysis across the entire wavelength range, avoiding the problem that key information may be missed in single-wavelength detection, thereby enhancing the comprehensiveness and accuracy of cutting quality assessment.

[0027] Map the spectral reflectance change rate of all sampling points into a two-dimensional matrix to generate a spectral difference map for identifying the spectral differences between the cut area and the uncut area; Set a change threshold T1. When > T1, it indicates that the area is a cut area; when ≤ T1, it indicates that the area is an uncut area; Through the comparison of spectral reflectance data with a reference map, calculating the spectral reflectance change rate, and generating a spectral difference map, the present invention realizes the accurate identification of the cut area and the uncut area. These steps not only solve the problem of difficult real-time monitoring of optical property changes in existing laser cutting technology, but also ensure the accurate determination of the cut area through the setting of the threshold T1, thereby improving the reliability of cutting path adjustment and cutting quality assessment, providing an innovative solution for the high-precision processing of perovskite thin films.

[0028] S5. Calculate the offset of the laser cutter according to the spectral difference map and dynamically adjust the cutting path according to the offset; Compare the spectral difference map with the target cutting path to determine the offset between the actual position of the cutter and the target path. The calculation formula for the offset is: ; where, represents the offset calculated by the laser cutter at the sampling point coordinates , represents the th sampling point at time normalized spectral reflectance change rate, represents the index variable of the sampling point, represents the th sampling point to the perpendicular distance of the target cutting path; When is a positive number: the laser cutting path is biased towards the uncut area and moves towards the uncut area; When When is zero: The laser cutting path is exactly located on the target path and no adjustment is required; The calculation of the offset is based on the spectral reflectance change rate and the distance from the sampling point to the target cutting path. By means of weighted average, the deviation of optical characteristics and geometric position is comprehensively considered. This design can dynamically reflect the actual offset degree of the cutting area; Traditional laser cutting technology usually relies on mechanical positioning and is difficult to perceive and adjust path offset in real time during the cutting process. However, the present invention provides a dynamic feedback mechanism by combining spectral data and path geometric offset, which can detect and correct path offset in real time during the cutting process, thus significantly improving the cutting accuracy. In addition, by assigning weights to the spectral data, it is possible to give priority to areas with significant optical changes and avoid misjudgment caused by local non-uniformity of the perovskite thin film.

[0029] According to the offset , dynamically adjust the laser cutting path to make it return to the target path and continue the cutting operation. After adjustment, it is necessary to re-collect spectral data, and cycle through spectral difference calculation and offset adjustment until the cutting path completely coincides with the target path; After cutting is completed, record the spectral reflectance change rate of all sampling points and the cutting path data, and generate a spectral reflectance change characteristic map of the cutting area based on these data; The present invention calculates the offset of the laser cutter by comparing the spectral difference map with the target path, and realizes the dynamic adjustment of the cutting path based on the offset, significantly improving the precision and quality of perovskite thin film cutting. The calculation of the offset comprehensively considers the changes in optical characteristics and geometric position deviations, ensuring the accuracy of the adjustment; the dynamic feedback mechanism enables the cutting process to be optimized in real time, avoiding quality problems caused by path offset in traditional technologies; the spectral characteristic map after cutting provides a scientific basis for quality assessment and process improvement. The design of the present invention has significant innovation and application value in solving the problem of precise cutting of perovskite thin films.

[0030] S6. After cutting is completed, perform quality inspection and output the final perovskite thin film sample and cutting data. After cutting is completed, scan the surface of the perovskite thin film again to generate the final spectral reflectance data; After laser cutting is completed, use a spectrometer to perform a full-coverage scan of the surface of the perovskite thin film, collect the spectral reflectance data of each grid area, and obtain the final spectral reflectance data , and after aggregating the spectral reflectance data of each grid area, obtain the final spectral reflectance distribution map; After cutting is completed, a spectrometer is used to perform a full-coverage scan of the perovskite thin film surface to collect spectral reflectance data for each grid area; the core of this concept is to comprehensively obtain the optical property changes of the perovskite thin film after cutting through high-resolution scanning to ensure the comprehensiveness and accuracy of the detection; In the prior art, the quality inspection of perovskite thin films after cutting usually relies on microscopic images or geometric measurements, which are difficult to comprehensively reflect the changes in optical properties; through the spectrometer scan in this step, the optical anomalies at the cutting edge, the residual spectral features in the uncut area, and the spectral deviation in the thermally damaged area can be accurately captured, thereby providing a comprehensive evaluation of the cutting quality; this method is particularly suitable for materials such as perovskite thin films that are sensitive to optical properties and can effectively solve the problem that traditional detection methods cannot identify microscopic defects; The present invention significantly improves the quality inspection ability of perovskite thin films after cutting by using a spectrometer to perform a full-coverage scan of the perovskite thin film surface after laser cutting to generate a final spectral reflectance distribution map; the spectrometer scan can comprehensively capture the optical property changes during the cutting process, especially the thermal damage in the edge area and the spectral deviation in the uncut residual area; the distribution map intuitively shows the optical state of the cutting area, providing data support for quality evaluation and subsequent encapsulation; compared with traditional geometric detection methods, the present invention solves the problem of difficult identification of microscopic defects through optical detection methods, which is of great significance for the precision processing of optically sensitive materials such as perovskite thin films; in addition, the output of cutting data provides a scientific basis for subsequent process optimization, with significant technical advantages and application value.

[0031] S7. Compare the final spectral reflectance data with the spectral reference reflectance value to confirm whether the cutting area completely covers the target path. When there is a cutting deviation, restart the device for supplementary cutting; According to the final spectral reflectance data and the spectral reference reflectance value , calculate the deviation value, and then substitute the deviation value into the spectral reflectance formula to obtain the spectral reflectance deviation , , the expression is: ; When the spectral reflectance deviation is zero, it means that the cutting area completely covers the target path and the cutting is accurate; When the spectral reflectance deviation is greater than zero, it means that there is a spectral deviation and the cutting is offset; Map the spectral reflectance deviations of all sampling points to a two-dimensional matrix to generate a spectral deviation distribution map for identifying the cutting deviation area; Set a deviation threshold T2; When When ≤ T2, it is considered that the cutting area is within the target path and the cutting is correct; When > T2, it is identified as a cutting deviation area; For the identified cutting deviation area, calculate the supplementary cutting path based on the spectral deviation distribution map, and obtain the offset of the sampling points in the supplementary cutting path According to the offset, start the device for supplementary cutting. The calculation formula for the supplementary cutting path is: ; Where represents the offset of the sampling point in the supplementary cutting path, which is used to adjust the cutting path of the laser cutter at this point, represents the vertical distance from the sampling point to the target cutting path, which is used to measure the spatial position of the cutting deviation, represents the spectral reflectance deviation of the th sampling point, represents the index variable of the sampling point, represents the total number of sampling points; When is a positive real number, start the device to supplement the cutting outside the target path; When is a negative real number, start the device to supplement the cutting inside the target path.

[0032] This embodiment also provides a computer device, which is applicable to the case of the perovskite thin film laser cutting and positioning method, including: a memory and a processor; the memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions to implement the perovskite thin film laser cutting and positioning method as proposed in the above embodiment.

[0033] The computer device can be a terminal. The computer device includes a processor, a memory, a communication interface, a display screen, and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner. The wireless manner can be implemented through WIFI, a carrier network, NFC (Near Field Communication), or other technologies. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer covered on the display screen, or a button, a trackball, or a touchpad set on the computer device housing, or an external keyboard, touchpad, or mouse, etc.

[0034] This embodiment also provides a storage medium, on which a computer program is stored. When the program is executed by a processor, it implements the perovskite thin film laser cutting positioning method proposed in the above embodiment; the storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (abbreviated as SRAM), electrically erasable programmable read-only memory (abbreviated as EEPROM), erasable programmable read-only memory (abbreviated as EPROM), programmable read-only memory (abbreviated as PROM), read-only memory (abbreviated as ROM), magnetic memory, flash memory, magnetic disk or optical disc.

[0035] In summary, the present invention: introduces spectral reflectance data into the cutting positioning and quality detection process, combines a spectrometer and a laser cutter to achieve dynamic feedback and adjustment. The present invention generates a spectral feature reference map of the uncut perovskite thin film, monitors the change of spectral reflectance during the cutting process of the perovskite thin film in real time, generates a spectral difference map and dynamically adjusts the laser cutting path accordingly, thereby significantly improving the cutting accuracy and quality. In addition, after cutting is completed, the present invention comprehensively evaluates the cutting quality of the perovskite thin film by using the comparative analysis of spectral reflectance, and performs supplementary cutting operations when necessary to ensure that the cutting area completely covers the target path, overcoming the defect of insufficient cutting quality detection means in the prior art. Therefore, the present invention solves the problems of cutting path deviation, insufficient cutting accuracy and incomplete quality detection in the existing perovskite thin film laser cutting technology.

[0036] Embodiment 2, referring to Table 1, is the second embodiment of the present invention. To further verify the technical solution of the present invention, experimental simulation data of the perovskite thin film laser cutting positioning method are given.

[0037] The purpose of this embodiment is to verify the advantages of the spectral reflectance distribution map generation technology proposed by the present invention in the quality detection of perovskite thin films after cutting; the test object is the perovskite thin film, and the goal is to detect the change of the spectral reflectance distribution after laser cutting and compare it with the prior art (traditional microscopic geometry detection method); the specific implementation process is as follows: Preparation of test samples Select a perovskite thin film sample with dimensions of 10 cm × 10 cm, a sample thickness of 500 nm, and the surface uniformity is controlled within the range of ±5%; fix the perovskite thin film on the laser cutting platform, set the laser cutting path as a group of continuous straight lines, with an interval of 1 mm and a total of 100 cutting paths; Laser cutting process Use a fiber laser with a wavelength of 1064 nm for cutting, set the power to 5 W, and the cutting speed to 10 mm / s; monitor the laser path in real time and dynamically adjust during the cutting process to ensure the cutting accuracy; after the cutting is completed, the surface of the perovskite thin film will show an obvious distribution of the cut area and the uncut area; Spectral data acquisition After the cutting is completed, use a spectrometer to perform a full-coverage scan of the surface of the perovskite thin film; divide the sample into 1 mm × 1 mm grid areas, with a total of 10,000 sampling points; record the spectral reflectance data at each grid point, the detection wavelength range is 400 nm - 800 nm, and the step size is 5 nm; after the scan is completed, collect the spectral data of all sampling points to generate a spectral reflectance distribution map; Comparison with the prior art Use the traditional microscopic geometry detection method to detect the cut perovskite thin film sample, mainly focusing on the cutting width, edge roughness, and the remaining situation in the uncut area; the microscopic image data is processed by manual analysis; Result recording and analysis Record the performance parameters of the present invention and the prior art in terms of edge detection of the cut area, detection of uncut residues, thermal damage identification, etc., and present them in a quantitative form.

[0038] Specifically as shown in Table 1 below:

[0039] It can be seen from the table data that the performance of the present invention in the quality detection of perovskite thin film cutting is significantly better than the prior art, especially showing obvious advantages in terms of cutting accuracy, detection efficiency, and thermal damage identification: Recognition accuracy of the cut area The recognition accuracy of the cut area of the present invention reaches 98.5%, which is 15.6% higher than 85.2% of the prior art. This advantage benefits from the generation of the spectral reflectance distribution map. By accurately analyzing the spectral characteristics of the cut area and the uncut area, the boundary between the two can be clearly distinguished, while the traditional microscopic geometry detection method only relies on image information and is easily affected by edge irregularities and optical interference.

[0040] Detection rate of residues in the uncut area The detection rate of the uncut area reaches 99.2% in the present invention, which is much higher than 87.4% of the prior art. The high resolution and full-coverage scanning method of spectral data enable even tiny uncut residual areas to be accurately captured, while small-area residues are likely to be missed by traditional methods due to resolution limitations.

[0041] Identification of thermal damage area The identification rate of the thermal damage area is one of the significant advantages of the present invention, reaching 96.8%, while it is only 70.5% in the prior art. During the laser cutting process, thermal damage will cause local changes in the optical properties of the perovskite thin film. Spectral reflectance detection can accurately capture these changes, while microscopic geometry detection is difficult to effectively identify the microscopic features at the edge of thermal damage.

[0042] Detection time and resolution The detection time of the present invention is 5.2 minutes, which is nearly 80% shorter than 25.8 minutes of the prior art. At the same time, the resolution of the spectral reflectance distribution map reaches 1 μm, which is significantly better than 10 μm of the microscopic geometry detection method. This result proves that the spectral scanning method not only improves the detection efficiency but also significantly enhances the data resolution.

[0043] False detection rate and automation level In terms of the false detection rate, the present invention is only 0.6%, which is significantly lower than 9.8% of the prior art. In addition, the data processing process of the present invention realizes 100% automation, while the traditional technology can only reach 30% automation due to relying on manual analysis. This shows that the present invention can effectively reduce human errors and improve the reliability and consistency of detection.

[0044] In summary, the present invention shows significant advantages in the quality detection of perovskite thin film after cutting through the spectral reflectance distribution map technology. It not only improves the accuracy of cutting area identification but also significantly optimizes the detection efficiency and automation level, solves the deficiencies of the prior art in thermal damage identification and uncut residue detection, and reflects its innovation and practical value.

[0045] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A method for positioning laser cutting of perovskite thin films, characterized in that: Including: Flatly fix the perovskite thin film sample on the laser cutting platform. Use a spectrometer to scan the surface of the uncut perovskite thin film, record the spectral reflectance distribution of each area, and generate a spectral feature reference map of the uncut perovskite thin film based on the spectral reflectance data. Start the laser cutter to cut the perovskite thin film, and use a spectrometer to collect the spectral reflectance data of the cutting area and its surroundings on the surface of the perovskite thin film. Compare and calculate the spectral reflectance data with the spectral feature reference map, identify the spectral differences between the cutting area and the uncut area, and generate a spectral difference map. According to the spectral difference map, calculate the offset of the laser cutter, and dynamically adjust the cutting path according to the offset. After cutting, conduct quality inspection, output the final perovskite thin film sample and cutting data. After cutting, scan the surface of the perovskite thin film again to generate the final spectral reflectance data. Compare the final spectral reflectance data with the spectral reference reflectance value to confirm whether the cutting area completely covers the target path. When there is a cutting deviation, restart the device for supplementary cutting.

2. The perovskite thin film laser cutting and positioning method according to claim 1, wherein: The step of flatly fixing the perovskite thin film sample on the laser cutting platform is specifically as follows: Use the electrostatic adsorption fixing method to firmly adsorb the perovskite thin film on the platform. Calculate the electrostatic adsorption force between the perovskite thin film and the surface of the control platform, and judge whether the perovskite thin film is firmly adsorbed. Set an adsorption force threshold. When the adsorption force is insufficient, readjust the potential difference and contact area. Use an optical microscope to verify whether the laser focus is located at the center layer of the perovskite thin film surface. When the distance from the laser focus to the perovskite thin film fixed platform is equal to the thickness of the perovskite thin film it means that the laser focus is located on the surface of the perovskite thin film; When the distance between the laser focus and the perovskite film fixing platform is greater than or less than the thickness of the perovskite film it indicates that the laser focus is offset, and the focal length parameter needs to be readjusted.

3. The perovskite thin film laser cutting and positioning method according to claim 2, wherein: The step of using a spectrometer to scan the surface of the uncut perovskite thin film, record the spectral reflectance distribution of each area, and generate a spectral feature reference map of the uncut perovskite thin film based on the spectral reflectance data is specifically as follows: The surface of the perovskite film is divided into grid regions, and respectively represent the number of divisions of the grid regions on the surface of the perovskite film in the horizontal and vertical directions. Each grid region corresponds to a sampling point, and the spectral reflectance of each sampling point represents that at a wavelength of , the spectral reflectance of the sampling point on the surface of the perovskite film, where correspond to the abscissa and ordinate of the sampling point in space; Integrate the spectral reflectance distribution of each sampling point to calculate its normalized spectral reflectance. The spectral reflectance formula is: ; Among them, represents the spectral reflectance at the sampling point after normalization, represents the shortest wavelength, represents the longest wavelength, represents the wavelength under the weight function, represents the integral of the infinitesimal change amount;​ The normalized spectral reflectance data is mapped to a two-dimensional matrix to generate a spectral feature reference map of the uncut perovskite film; Store the collected spectral reflectance data and reference map as a two-dimensional matrix file.

4. The perovskite thin film laser cutting and positioning method according to claim 3, characterized in that: The step of starting the laser cutter to cut the perovskite thin film and using a spectrometer to collect the spectral reflectance data of the cutting area and its surroundings on the surface of the perovskite thin film is specifically as follows: The laser cutter starts the cutting work according to the preset target path. During cutting, continuously collect the spectral reflectance data of the cutting area and its surroundings through a spectrometer. For each sampling point, record its spectral reflectance curve changing with time.

5. The perovskite thin film laser cutting and positioning method according to claim 4, characterized in that: The step of comparing and calculating the spectral reflectance data with the spectral feature reference map, identifying the spectral differences between the cutting area and the uncut area, and generating a spectral difference map is specifically as follows: Calculate the change of spectral reflectance at each sampling point over time to obtain the spectral reflectance change rate, and the expression is: ; Among them, represents the sampling point The change rate of the normalized spectral reflectance at time ; represents the sampling point The spectral reference reflectance value on the surface of the uncut perovskite thin film represents at wavelength At a certain sampling point on the surface of the perovskite thin film At time The spectral reflectance; Map the spectral reflectance change rates of all sampling points into a two-dimensional matrix to generate a spectral difference map; ​ Set a change threshold T1. When > T1, it indicates that this area is a cut area; when ≤ T1, it indicates that this area is an uncut area.

6. The perovskite thin film laser cutting and positioning method according to claim 5, wherein: The step of calculating the offset of the laser cutter according to the spectral difference map and dynamically adjusting the cutting path according to the offset is specifically as follows: Compare the spectral difference diagram with the target cutting path to determine the offset between the actual position of the cutter and the target path. The calculation formula for the offset is: ; Among them, represents the offset calculated by the laser cutter at the sampling point coordinates ; represents the th sampling point at time the normalized spectral reflectance change rate; represents the index variable of the sampling point, represents the total number of sampling points, represents the th sampling point the perpendicular distance to the target cutting path; When is a positive number, the laser cutting path is biased towards the uncut area and moves towards the uncut area; When is negative, the laser cutting path is biased towards the cut area and adjusted towards the inside of the cut area; When is zero, the laser cutting path is accurately located on the target path without adjustment; According to the offset , dynamically adjust the laser cutting path to return it to the target path and continue the cutting operation; After cutting is completed, record the spectral reflectance change rates of all sampling points and the cutting path data, and generate a spectral reflectance change characteristic diagram of the cutting area.

7. The perovskite thin film laser cutting and positioning method according to claim 6, characterized in that: The step of conducting quality inspection after cutting, outputting the final perovskite thin film sample and cutting data, and scanning the surface of the perovskite thin film again after cutting to generate the final spectral reflectance data is specifically as follows: After the laser cutting is completed, a spectrometer is used to perform a full-coverage scan of the perovskite thin film surface, collect the spectral reflectance data of each grid area, and obtain the final spectral reflectance data , and after collecting the spectral reflectance data of each grid area, the final spectral reflectance distribution map is obtained.

8. The perovskite thin film laser cutting and positioning method according to claim 7, characterized in that: The step of comparing the final spectral reflectance data with the spectral reference reflectance value to confirm whether the cutting area completely covers the target path. When there is a cutting deviation, restart the device for supplementary cutting is specifically as follows: According to the final spectral reflectance data and the spectral reference reflectance value , calculate the deviation value, and then substitute the deviation value into the spectral reflectance formula to obtain the spectral reflectance deviation ; When the spectral reflectance deviation is zero, it indicates that the cutting area completely covers the target path and the cutting is accurate without error; When the spectral reflectance deviation is greater than zero, it indicates the existence of spectral deviation and offset in cutting; Map the spectral reflectance deviations of all sampling points into a two-dimensional matrix to generate a spectral deviation distribution map; Set a deviation threshold T2. When ≤ T2, it is considered that the cutting area is within the target path and the cutting is correct; When > T2, it is recognized as a cutting deviation area; For the identified cutting deviation area, calculate a supplementary cutting path based on the spectral deviation distribution diagram, and obtain the offset of the sampling points in the supplementary cutting path. Start the device for supplementary cutting according to the offset.

9. A computer device, comprising a memory and a processor, the memory storing a computer program, characterized in that: When the processor executes the computer program, the steps of the perovskite thin film laser cutting and positioning method according to any one of claims 1 to 8 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by the processor, the steps of the perovskite thin film laser cutting and positioning method according to any one of claims 1 to 8 are implemented.

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