Method, system and equipment for adjusting a worktable based on MicroLED transfer state

Abstract

This invention relates to the field of chip transfer technology, specifically to a method, system, and device for adjusting a worktable based on the MicroLED transfer state. The method involves: acquiring the actual size of the working area and dividing it according to preset imaging field requirements and the actual size to obtain area division data; obtaining the intermediate area from the area division data; acquiring imaging data of the intermediate area by longitudinally moving the worktable and using an imaging observation component to obtain an imaging data sequence; analyzing the imaging data sequence according to a preset image sharpness evaluation function to obtain a correspondence; determining the entry into the MicroLED transfer state based on the correspondence; adjusting the worktable according to preset verification conditions and the MicroLED transfer state; dividing the working area based on the intermediate area, pre-calibrating and matching the optimal state, ensuring complete and accurate acquisition through partitioning design, dynamically adjusting and correcting deviations, improving the alignment accuracy between the MicroLED chip and the electrode, and contributing to improved transfer yield.

Description

Technical Field

[0001] This invention relates to the field of chip die transfer technology, and more specifically to a worktable adjustment method, system, and device based on the transfer state of MicroLEDs. Background Technology

[0002] Laser mass transfer is a core process in MicroLED display manufacturing. Its yield is critically dependent on ensuring optimal spacing and precise alignment between each MicroLED chip on the transparent carrier substrate and the electrode positions on the target substrate. However, in actual operation, the transparent carrier substrate and the target substrate are prone to slight tilting, directly causing problems such as chip-electrode spacing deviations from the optimal value and misalignment, severely impacting the transfer effect. Current technologies lack real-time monitoring and dynamic correction capabilities for the relative position and attitude of the two substrates, making it difficult to detect tilting issues in a timely manner; they also lack control mechanisms for the X, Y, and Z-axis displacement and rotation of the laser mass transfer stage, making it impossible to simultaneously correct both spacing discrepancies and misalignment; furthermore, they lack dynamic attitude adjustment strategies adapted to mass transfer scenarios. These deficiencies lead to insufficient chip-electrode alignment accuracy, directly hindering the improvement of laser mass transfer yield and becoming a core technical bottleneck for the industry's large-scale application of this process. Summary of the Invention

[0003] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide a worktable adjustment method, system and device based on the MicroLED transfer state.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0005] This invention provides a stage adjustment method based on MicroLED transfer state, applied to a stage adjustment system based on MicroLED transfer state. The stage adjustment system includes a stage and an imaging observation component. The stage has a working area. The stage adjustment method includes: acquiring the actual size of the working area and dividing the working area according to preset imaging field of view requirements and the actual size to obtain area division data; obtaining an intermediate area from the area division data; moving the stage longitudinally and acquiring imaging data of the intermediate area through the imaging observation component to obtain an imaging data sequence; analyzing the imaging data sequence according to a preset image sharpness evaluation function to obtain a correspondence; determining the entry into the MicroLED transfer state based on the correspondence; and adjusting the stage according to preset verification conditions and the MicroLED transfer state.

[0006] Furthermore, the step of analyzing the imaging data sequence according to a preset image sharpness evaluation function to obtain a correspondence includes: analyzing the imaging data sequence according to the image sharpness evaluation function to obtain sharpness value data; mapping the imaging data sequence to obtain working distance data; and constructing a correspondence based on the sharpness value data and the working distance data.

[0007] Furthermore, the adjustment of the worktable according to the preset verification conditions and MicroLED transfer status includes: performing a status analysis on the MicroLED transfer status; when the MicroLED transfer status is that a transfer is completed in one go, acquiring the current imaging data of the middle area through the imaging observation component to obtain the first imaging data; obtaining the left and right areas from the area division data according to the preset optimal working distance range; and adjusting the worktable according to the verification conditions, the first imaging data, the left and right areas.

[0008] Furthermore, the stage adjustment system based on the MicroLED transfer state further includes multiple electrodes, comprising: analyzing the left and right regions according to a preset difference threshold to obtain a tilt angle; adjusting the stage according to the tilt angle; acquiring imaging data of the left region through an imaging observation component to obtain second imaging data; acquiring imaging data of the right region through an imaging observation component to obtain third imaging data; performing feature analysis on the first, second, and third imaging data according to a preset automatic image recognition algorithm to obtain feature analysis results and offset degree; determining whether the feature analysis results meet the verification condition that the electrode cannot be observed; if the feature analysis results do not meet the verification condition that the electrode cannot be observed, adjusting the stage according to the offset degree, and returning to the process of acquiring imaging data of the middle region through the imaging observation component until the feature analysis results meet the verification condition that the electrode cannot be observed.

[0009] Further, the step of analyzing the left and right regions according to a preset difference threshold to obtain the tilt angle includes: obtaining the working distance of the left region to obtain the left distance; obtaining the working distance of the right region to obtain the right distance; calculating the difference between the left and right distances to obtain the distance difference; determining whether the distance difference is greater than or less than the difference threshold; when the distance difference is greater than or less than the difference threshold, obtaining the horizontal distance between the left and right regions; and approximating the distance difference and horizontal distance using a formula based on the preset tilt angle to obtain the tilt angle.

[0010] Furthermore, the step of obtaining the left and right regions from the region division data according to the preset optimal working distance range includes: analyzing the first imaging data according to the image sharpness evaluation function to obtain a sharpness value; obtaining the working distance from the correspondence based on the sharpness value; determining whether the working distance is within the optimal working distance range; and obtaining the left and right regions from the region division data when the working distance is within the optimal working distance range.

[0011] Furthermore, the stage adjustment system based on the MicroLED transfer state executes the stage adjustment method based on the MicroLED transfer state as described above. The stage adjustment system based on the MicroLED transfer state includes a mass transfer device, an imaging observation component, a mask projection component, and an illumination optical path component. The light emission direction of the mask projection component faces the input end of the mass transfer device; the light emission direction of the imaging observation component faces the input end of the mass transfer device, and the imaging observation component is located above the mass transfer device; the light emission direction of the illumination optical path component faces the input end of the mass transfer device; the light emission directions of the mask projection component, the imaging observation component, and the illumination optical path component share a common optical path.

[0012] Furthermore, the mass transfer device includes multiple MicroLED chip chips, a transparent carrier substrate, a target substrate, a stage, and multiple electrodes. The target substrate is disposed on the stage, and the multiple electrodes are distributed on the target substrate. Multiple MicroLED chip chips are arrayed on the transparent carrier substrate, and each MicroLED chip chip is located above the multiple electrodes. A transfer position is formed between any two adjacent electrodes, and the transfer position is used to carry the MicroLED chip chip. The light emission direction of the mask projection component, the light emission direction of the imaging observation component, and the light emission direction of the illumination optical path component are all directed towards the multiple MicroLED chip chips. The mask projection component is used to provide laser pulse irradiation to the multiple MicroLED chip chips. Under laser pulse irradiation, the multiple MicroLED chip chips are transferred from the transparent carrier substrate to their respective corresponding transfer positions.

[0013] Further, the mask projection assembly includes a laser, a beam attenuation module, a first reflector, a beam expander, a second reflector, a homogenization and shaping module, a mask, a front group of projection lenses, a first beam splitter, and a rear group of projection lenses; the light emission direction of the laser is towards the input end of the beam attenuation module, the light emission direction of the beam attenuation module is towards the input end of the first reflector, the light emission direction of the first reflector is towards the input end of the beam expander, the light emission direction of the beam expander is towards the input end of the second reflector, and the light emission direction of the second reflector is towards the input end of the homogenization and shaping module. The homogenization and shaping module, the beam attenuation module, the beam expander, the beam splitter ... attenuation module, the beam expander, the beam splitter, the beam splitter, the beam expander, the beam splitter, the beam splitter, the beam attenuation module, the beam expander, the beam splitter, the beam splitter, the beam expander, the beam splitter, the beam splitter, the beam expander, the beam splitter, the beam splitter, the beam expander, the beam splitter, the beam splitter, the beam expander, the beam splitter, the beam expander, the beam splitter, the beam splitter, the beam expander, the beam splitter, the beam expander, the beam splitter, the beam expander, the beam splitter, the beam splitter, the beam expander, the The photomask and the front group of the projection lens are coaxially arranged; the light emission direction of the homogenization and shaping module is towards the input end of the photomask, the light emission direction of the photomask is towards the input end of the front group of the projection lens, the light emission direction of the front group of the projection lens is towards the input end of the first beam splitter; the light emission direction of the first beam splitter is towards the input end of the rear group of the projection lens; the light emission direction of the rear group of the projection lens is towards the input end of the mass transfer device; the photomask is provided with an array of rectangular holes, and the multiple rectangular holes allow the laser beam passing through them to be projected onto the mass transfer device in a proportionally reduced manner.

[0014] Furthermore, the stage adjustment device based on the MicroLED transfer state includes: a memory and at least one processor, wherein the memory stores instructions; at least one processor invokes the instructions in the memory to cause the stage adjustment device based on the MicroLED transfer state to perform the various steps of the stage adjustment method based on the MicroLED transfer state as described above.

[0015] In the technical solution of this invention, the working area is first divided according to the actual size of the working area and the imaging field of view requirements. Taking the middle area, which is less affected by posture errors, as the benchmark, the calibration distortion problem in the edge area is effectively avoided, ensuring data reliability. Through pre-calibration, a one-to-one correspondence between the working distance and imaging clarity between the transparent carrier substrate and the target substrate is established. During transfer, the optimal state can be quickly matched without the need for complex real-time calculations. This adapts to the high pulse efficiency requirements of mass transfer. The partition design based on the field of view adaptability requirements ensures both complete image acquisition and accurate feature extraction, while avoiding background noise interference. With the help of a dynamic adjustment mechanism, the substrate spacing and posture deviation are accurately corrected, improving the alignment accuracy of the MicroLED chip and the electrode, and helping to improve the transfer yield. Attached Figure Description

[0016] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0017] Figure 1This is a first flowchart of a worktable adjustment method based on MicroLED transfer state provided in an embodiment of the present invention;

[0018] Figure 2 This is a second flowchart of a worktable adjustment method based on MicroLED transfer state provided in an embodiment of the present invention;

[0019] Figure 3 This is a third flowchart of a worktable adjustment method based on MicroLED transfer state provided in an embodiment of the present invention;

[0020] Figure 4 This is a fourth flowchart of a worktable adjustment method based on MicroLED transfer state provided in an embodiment of the present invention;

[0021] Figure 5 A fifth flowchart of a worktable adjustment method based on MicroLED transfer state provided in an embodiment of the present invention;

[0022] Figure 6 A sixth flowchart of a worktable adjustment method based on MicroLED transfer state provided in an embodiment of the present invention;

[0023] Figure 7 This is a schematic diagram of the worktable adjustment system based on MicroLED transfer state provided in an embodiment of the present invention;

[0024] Figure 8 This is a schematic diagram of the mass transfer device provided in an embodiment of the present invention;

[0025] Figure 9 This is a schematic diagram of the worktable adjustment device based on the MicroLED transfer state provided in an embodiment of the present invention.

[0026] Figure Labels

[0027] 10-Laser; 20-Beam attenuation module; 31-First reflecting mirror; 40-Beam expander module; 32-Second reflecting mirror; 50-Homogenization and shaping module; 60-Mask; 71-Front group of projection lens; 72-Rear group of projection lens; 73-Front group of imaging objective lens; 74-Illumination lens group; 81-First beam splitter; 82-Second beam splitter; 90-Working surface; 91-Transparent carrier substrate; 92-MicroLED chip die; 94-Target substrate; 95-Electrode; 96-Working stage; 100-Camera; 110-Illumination source. Detailed Implementation

[0028] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" or "having" and any variations thereof are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0029] In actual production, laser mass transfer of MicroLED chip dies is performed based on mask projection. Multiple MicroLED chip dies can be transferred with a single laser pulse, resulting in extremely high transfer efficiency. Typically, the relative position of the target substrate 94 and the transparent carrier substrate 91 will only deviate from the normal operating range after many pulse transfers. Therefore, the online monitoring method and process are only used to correct problems in the operation of the mass transfer equipment in a timely manner and will not affect the working efficiency of the mass transfer process.

[0030] A stage adjustment method based on MicroLED transfer state is applied to a stage adjustment system based on MicroLED transfer state. The stage adjustment system includes a transparent carrier substrate, a target substrate, a stage, and an imaging observation component. The target substrate is disposed on the stage, and the transparent carrier substrate is disposed above the target substrate, with a working distance formed between them. A working area is provided on the stage. For ease of understanding, the specific process of this embodiment is described below. Please refer to [link to relevant documentation]. Figure 1 One embodiment of the worktable adjustment method based on the MicroLED transfer state in this invention includes:

[0031] 101. Obtain the actual size of the working area, and divide the working area according to the preset imaging field of view requirements and the actual size to obtain the area division data;

[0032] In this embodiment, the actual size of the working area is first obtained, and then divided into three zones (left, middle, and right) according to the imaging field of view requirements and the actual size (these zones can be separated, connected, or partially overlapped). The middle zone is preferentially selected as the calibration and monitoring benchmark. The area of ​​the middle zone is smaller than the entire working area, and it is less affected by positional errors such as substrate tilt and misalignment. It can more purely reflect the correlation between working distance and imaging clarity, avoiding calibration distortion caused by substrate posture deviation in the edge areas, and providing an accurate benchmark for subsequent correspondence construction. The imaging field of view requirements specifically include the field of view coverage requirements: each zone (especially the middle zone) must completely fall within the imaging field of view to ensure the integrity of the zone image. Complete, without edge cropping or missing information; Resolution requirements: The field of view resolution must match the size of the MicroLED chip and electrode (e.g., be able to clearly distinguish the chip outline and electrode edge) to ensure that the image sharpness evaluation function can extract effective gradient features; Field of view stability requirements: The distortion rate of the imaging field of view must be lower than a preset threshold (e.g., a few per thousand) to avoid distortion of image features within the partition due to field of view deformation, affecting the accuracy of the correspondence between working distance and sharpness; Adaptability requirements: The size of the field of view must match the partition size, neither too small to prevent the partition image from being completely acquired, nor too large to introduce irrelevant background noise, balancing acquisition efficiency and feature extraction accuracy;

[0033] 102. Obtain the intermediate region from the regional division data;

[0034] In this embodiment, the working area is divided into three parts: left, middle, and right. The three parts can be completely separated, connected, or partially overlapped. The specific location of the three parts depends on the actual size of the working area and the requirements of the image processing algorithm for the imaging field of view.

[0035] 103. By moving the worktable longitudinally and acquiring imaging data of the intermediate area through the imaging observation component, an imaging data sequence is obtained;

[0036] In this embodiment, before the mass transfer system works, the imaging effect of the target substrate 94 and the transparent carrier substrate 91 at different working distances should be calibrated. The distance between the target substrate 94 and the transparent carrier substrate 91 can be changed by moving the stage longitudinally, so that the MicroLED target substrate 94 and the transparent carrier substrate 91 are at multiple different discrete distances, and the working area is imaged and photographed respectively to form an imaging data sequence.

[0037] 104. Analyze the imaging data sequence according to the preset image sharpness evaluation function to obtain the corresponding relationship;

[0038] In this embodiment, the correspondence is between the working distance between the transparent carrier substrate and the target substrate and the image sharpness evaluation function value. Since the area of ​​the middle region is smaller than the area of ​​the entire working area, the image sharpness of the middle region is less affected by relative position errors such as tilt and misalignment between the target substrate and the transparent carrier substrate. A one-to-one correspondence between different working distances and the image sharpness evaluation function value is established and stored in the device operating software. The image sharpness evaluation function is used to analyze the image sharpness evaluation function value of the corresponding image in the middle region when the target substrate 94 and the transparent carrier substrate 91 are at different working distances.

[0039] 105. Determine the MicroLED transfer state based on the corresponding relationship;

[0040] In this embodiment, the transfer state refers to confirming, based on the pre-stored correspondence between "resolution value and working distance", that the working distance corresponding to the current imaging resolution of the intermediate region is within the optimal range, and that the relative distance and initial posture of the target substrate and the transparent carrier substrate meet the requirements for stable transfer of MicroLED chip chips. A laser pulse can then be activated to achieve the precise transfer of the chip from the transparent carrier substrate to the target substrate.

[0041] 106. Adjust the worktable according to the preset verification conditions and MicroLED transfer status;

[0042] In this embodiment, the working area is first divided according to the actual size of the working area and the imaging field of view requirements. The middle area, which is less affected by posture errors, is used as the benchmark to effectively avoid calibration distortion in the edge area and ensure data reliability. A one-to-one correspondence between the working distance and imaging clarity between the transparent carrier substrate and the target substrate is established through pre-calibration. The optimal state can be quickly matched during transfer without the need for complex real-time calculations. This adapts to the high pulse efficiency requirements of mass transfer. The partition design based on the field of view adaptability requirements ensures both complete image acquisition and accurate feature extraction while avoiding background noise interference. With the help of a dynamic adjustment mechanism, the substrate spacing and posture deviation are accurately corrected, improving the alignment accuracy of the MicroLED chip and the electrode and helping to improve the transfer yield.

[0043] Please see Figure 2 In the second embodiment of the worktable adjustment method based on the MicroLED transfer state in this invention, step 104 includes:

[0044] 201. Analyze the imaging data sequence according to the image sharpness evaluation function to obtain sharpness value data;

[0045] In this embodiment, the image sharpness evaluation function includes the Tenengrad function, gray-level gradient function, gray-level entropy function, and frequency domain functions. The Tenengrad function is used as an example to explain the basic concepts of image sharpness evaluation functions. The Tenengrad function uses Gaussian smoothing and the Sobel operator with differentiation, which has a good suppression effect on noise in the image and is a high-performance gradient function. Therefore, this embodiment chooses the Tenengrad function to create a new image evaluation function. The Tenengrad function uses the Sobel operator to extract the gradient values ​​in the horizontal and vertical directions of the image respectively. The two-dimensional gradient distribution Y(x,y) of the image can be represented as:

[0046] In the formula, These are the two-dimensional coordinates of the pixels in the image. For the imaging gradient magnitude, Let be the gradient function of the first image; the gradient value in the horizontal direction of the image can be calculated from it. The gradient function for the second image can be used to calculate the gradient value in the vertical direction of the image. , The specific calculation formula belongs to the basic formulas in the field of image processing.

[0047] Based on the two-dimensional gradient distribution of the image, the image sharpness evaluation function value MF can be further obtained:

[0048] m represents the maximum number of pixels in the X direction, and n represents the maximum number of pixels in the Y direction;

[0049] 202. Obtain working distance data by mapping the imaging data sequence;

[0050] 203. A corresponding relationship is constructed based on the resolution value data and the working distance data;

[0051] In this embodiment, the distance between the target substrate 94 and the transparent carrier substrate 91 can be changed by moving the worktable longitudinally, thereby establishing the correspondence between the target substrate 94 and the transparent carrier substrate 91 at different working distances and the clarity of the observed image.

[0052] In this embodiment, the Tenengrad function, which combines Gaussian smoothing and the Sobel operator, is selected. It has excellent noise suppression effect on images and can accurately extract gradient values ​​in the horizontal and vertical directions. The sharpness is calculated by the sum of squared gradients, ensuring the reliability and accuracy of the sharpness data. Based on the longitudinal moving stage, imaging data sequences under multiple discrete working distances are obtained and mapped to the working distance data. Then, a one-to-one correspondence between sharpness values ​​and working distances is established, providing a quantitative basis for judging the transfer status. This correspondence can be directly called without the need for complex real-time calculations. It is suitable for the high pulse efficiency requirements of laser mass transfer, can quickly lock the optimal working distance, reduce the impact of spacing deviation on the transfer, and improve the alignment accuracy of MicroLED chip chips and electrodes, providing key support for improving the transfer yield.

[0053] Please see Figure 3 In the third embodiment of the worktable adjustment method based on the MicroLED transfer state in this invention, step 106 includes:

[0054] 301. Perform state analysis on the MicroLED transfer state;

[0055] 302. When the MicroLED transfer status is "one transfer completed", the current imaging data of the middle area is collected by the imaging observation component to obtain the first imaging data.

[0056] 303. Obtain the left and right regions from the region division data based on the preset optimal working distance range;

[0057] In this embodiment, the left and right regions are precisely retrieved from the region division data based on the optimal working distance range. This ensures that the subsequent posture correction is based on the compliant spacing, avoids adjustment failure due to working distance deviation, improves the effectiveness of correction, adapts to the high-efficiency requirements of laser mass transfer, and provides key support for accurately correcting substrate tilt and improving the alignment accuracy of the grain and electrode.

[0058] 304. Adjust the worktable according to the verification conditions, the first imaging data, the left area, and the right area;

[0059] In this embodiment, the first imaging data (middle area) provides a precise reference, and the attitude information of the left and right areas is combined to make precise adjustments to the worktable according to the verification conditions. The substrate tilt is corrected by the data of the left and right areas, and the effectiveness of the adjustment is controlled by the verification conditions. This comprehensively solves the problem of misalignment between the die and the electrode, improves the alignment accuracy, and the adjustment is triggered only as needed. It does not interfere with the efficient mass transfer process, adapts to different transfer scenarios, reduces the implementation cost, and provides key support for improving the transfer yield.

[0060] In this embodiment, by accurately analyzing the MicroLED transfer state, the operation is triggered only after one transfer is completed, without interfering with the efficient mass transfer process. The first imaging data of the middle area is collected to provide a reliable benchmark. Then, based on the preset optimal working distance range, the left and right areas are retrieved to ensure that subsequent corrections are based on compliant spacing and to avoid adjustment failures. Relying on the benchmark data and the posture information of the left and right areas, the worktable is precisely adjusted according to the verification conditions to effectively correct the substrate tilt. The adjustment is triggered as needed, providing key support for improving the transfer yield.

[0061] Please see Figure 4 The stage adjustment system based on MicroLED transfer state further includes multiple electrodes. In the fourth embodiment of the stage adjustment method based on MicroLED transfer state in this invention, step 304 includes:

[0062] 401. Analyze the left and right regions according to the preset difference threshold to obtain the tilt angle;

[0063] 402. Adjust the worktable according to the tilt angle;

[0064] In this embodiment, by calculating the image clarity of the left and right sides, the working distance between the left and right sides and the target substrate is further mapped. The tilt angle between the carrier substrate and the target substrate is accurately quantified based on the distance difference between the left and right sides and the target substrate. If the tilt angle is greater than the threshold set by the system, it indicates that the tilt angle of the target substrate will affect the MicroLED transfer yield. The system will feed back the tilt angle to the stage and compensate for the tilt angle by adjusting the angle of the stage to ensure that the carrier substrate and the target substrate are kept in a parallel working state, avoiding chip and electrode misalignment caused by posture deviation and improving alignment accuracy. If the tilt angle between the carrier substrate and the target substrate is less than the set threshold, it indicates that the tilt angle is small and will not have an adverse effect on the chip transfer process. In this case, the stage does not need to compensate for the tilt angle.

[0065] 403. Acquire imaging data of the left region using the imaging observation component to obtain the second imaging data;

[0066] 404. Acquire imaging data of the right region using the imaging observation component to obtain the third imaging data;

[0067] 405. Perform feature analysis on the first imaging data, the second imaging data, and the third imaging data according to the preset automatic image recognition algorithm to obtain the feature analysis results and the degree of offset;

[0068] In this embodiment, the feature analysis principle of the automatic image recognition algorithm is to extract key features such as electrode contours and grayscale distribution in the image through techniques such as grayscale thresholding and edge detection (e.g., Sobel operator). The grayscale features of the electrode region differ from those of the region obscured by the die. The algorithm focuses on capturing the image signal corresponding to this difference and matches the extracted features with a preset fully aligned reference template (i.e., an electrode-free feature template when the die completely obscures the electrode). If no electrode features are detected, the alignment is considered satisfactory, and the feature analysis result is no visible electrode. If electrode contours, grayscale anomalies, or other features are detected, misalignment is identified, and the feature analysis result is an observable electrode. Based on... The imaging data from the three regions (first imaging data, second imaging data, and third imaging data) can determine whether the position of each MicroLED chip 92 to be transferred on the transparent carrier substrate 91 is precisely aligned with the electrode position on the target substrate 94. If the MicroLED chip 92 is precisely aligned with the transfer position, the MicroLED chip 92 will completely block the electrode 95 in the imaging image. Otherwise, the image information of the electrode 95 will be visible in the observation image. The feature analysis process is the analysis process of whether the electrode will appear in the image. The degree of misalignment between the MicroLED chip 92 and the transfer position can be determined through the imaging data.

[0069] 406. Determine whether the feature analysis results meet the verification condition that the electrode cannot be observed;

[0070] 407. If the feature analysis results do not meet the verification conditions that the electrode cannot be observed, the stage is adjusted according to the degree of offset, and the process is returned to collect imaging data of the intermediate area through the imaging observation component until the feature analysis results meet the verification conditions that the electrode cannot be observed.

[0071] In this embodiment, assuming that each MicroLED chip die 92 to be transferred on the transparent carrier substrate 91 is precisely aligned with the electrode position on the target substrate 94, the MicroLED chip die 92 will completely cover the electrode 95. If the MicroLED chip die 92 does not completely cover the electrode 95, the degree of offset will be fed back to the control unit, and the stage will be controlled to translate or rotate until the verification condition that the electrode 95 cannot be observed in the imaging data is met.

[0072] In this embodiment, the tilt angle is first quantified based on the distance difference between the left and right regions, and the stage is precisely adjusted to eliminate macroscopic tilt. Then, an automatic image recognition algorithm is used to extract the feature differences between the electrodes and the grains in the three-zone imaging data. The alignment status is accurately determined and the degree of offset is quantified based on complete occlusion. If misalignment exists, the stage is adjusted according to the degree of offset until no electrodes are visible. This solution addresses tilt and misalignment issues in a layered manner, improving alignment accuracy and effectively avoiding transfer failures caused by grain and electrode misalignment. The algorithm's judgment logic is intuitive and does not interfere with the efficient mass transfer process. It can be implemented using existing equipment, providing core support for improving transfer yield.

[0073] Please see Figure 5 In the fifth embodiment of the worktable adjustment method based on the MicroLED transfer state in this invention, step 401 includes:

[0074] 501. Obtain the working distance of the left region to get the left distance;

[0075] 502. Obtain the working distance of the right region to get the right distance;

[0076] In this embodiment, the working distances (left distance and right distance) of the left and right regions are obtained respectively. The two symmetrically distributed regions are used as the core basis for tilt judgment. The difference in their working distances directly maps the tilt state of the substrate. When the substrate is horizontal, the distances of the two regions are the same, and when it is tilted, a difference is generated.

[0077] 503. Calculate the difference between the left and right distances to obtain the distance difference;

[0078] 504. Determine whether the distance difference is greater than or less than the difference threshold;

[0079] In this embodiment, the difference threshold is, for example, zero. Setting the difference threshold to zero conforms to the physical common sense that the distance between symmetrical regions is equal in a horizontal state. The judgment logic is intuitive and easy to understand, and no complex threshold calibration is required. The tilt is only judged when the difference is non-zero, which effectively avoids misjudgment caused by minor noise and improves the reliability of tilt recognition.

[0080] 505. When the distance difference is greater than or less than the difference threshold, obtain the horizontal distance between the left and right regions.

[0081] In this embodiment, the target substrate 94 and the transparent carrier substrate 91 are determined to be tilted based on the working distances corresponding to the left and right regions. Assuming the difference between the working distances corresponding to the left and right regions is Δd13, if Δd13≠0, it indicates that the target substrate 94 and the transparent carrier substrate 91 are tilted.

[0082] 506. The tilt angle can be approximated by using a formula to calculate the distance difference and horizontal distance based on the preset tilt angle.

[0083] In this embodiment, it is assumed that the horizontal distance between the centers of the left and right regions is... The tilt angle between the target substrate 94 and the transparent carrier substrate 91 can be expressed by the formula... The angle is approximately calculated. Then, the tilt angle θ is fed back to the worktable for tilt adjustment.

[0084] In this embodiment, the working distance between the left-symmetrical region and the right-symmetrical region is collected and the difference is calculated. Zero is used as the threshold to determine whether the substrate is tilted. This is consistent with physical common sense and logically intuitive, improving the reliability of tilt recognition. When there is a distance difference, the tilt angle is quantified by an approximate formula by combining the horizontal distance between the centers of the two regions, transforming qualitative tilt into quantitative basis and providing precise guidance for worktable adjustment. The tilt angle is directly fed back to the worktable for rotation correction. The action is highly targeted and can quickly correct the substrate posture, avoiding misalignment of the grains and electrodes caused by tilt. This meets the high-efficiency requirements of laser mass transfer, while improving alignment accuracy, providing key support for improving transfer yield, adapting to different substrate specifications, and reducing the cost of industrialization.

[0085] Please see Figure 6 In the sixth embodiment of the worktable adjustment method based on the MicroLED transfer state in this invention, step 303 includes:

[0086] 601. Analyze the first imaging data according to the image sharpness evaluation function to obtain the sharpness value;

[0087] In this embodiment, the first imaging data comes from the middle area, which is less affected by substrate tilt and misalignment. Its clarity can purely reflect the change in working distance, ensuring that the clarity value can truly map the working distance state.

[0088] 602. Obtain the working distance from the corresponding relationship based on the sharpness value;

[0089] 603. Determine whether the working distance is within the optimal working distance range;

[0090] 604. When the working distance is within the optimal working distance range, the left and right regions are obtained from the region division data.

[0091] In this embodiment, when the working distance is not within the optimal working distance range, feedback is sent to the worktable for longitudinal displacement until it is within the optimal working distance range;

[0092] In this embodiment, the first imaging data is acquired based on the middle region, which is less affected by substrate tilt and misalignment. Its sharpness can purely reflect the change in working distance. Combined with the sharpness value obtained by the image sharpness evaluation function, it can accurately map the actual working distance state. Relying on the pre-stored correspondence between "sharpness value and working distance", the current working distance can be quickly matched without the need for complex real-time calculations. This adapts to the high pulse efficiency requirements of laser mass transfer. By judging whether the working distance is within the optimal range, if the working distance is not within the optimal working distance range, the longitudinal displacement adjustment of the stage is triggered until it is within the optimal working distance range. Then, the left and right regions are corrected to avoid subsequent adjustment failures due to spacing deviations. This lays a solid foundation for the precise alignment of MicroLED chip chips and electrodes and helps improve the transfer yield.

[0093] The above describes the stage 96 adjustment method based on the MicroLED transfer state in the embodiments of the present invention. The following describes the stage 96 adjustment system based on the MicroLED transfer state in the embodiments of the present invention. Please refer to [link / reference]. Figure 7This invention provides an embodiment of a stage 96 adjustment system based on MicroLED transfer state, comprising a mass transfer device and an imaging observation component. The imaging observation component includes a front imaging objective lens group 73 and a camera 100, a mask projection component, and an illumination optical path component. The illumination optical path component includes an illumination lens group 74, an illumination source 110, and a second beam splitter 82. The illumination source 110 is a monochromatic light source, typically a blue, green, or red monochromatic point light source. The light emitted from the illumination source 110 passes through the illumination lens group 74 and the rear projection lens group 72, and is approximately uniformly illuminated at the working surface 90. The light output direction of the mask projection component faces the input end of the mass transfer device; the light output direction of the imaging observation component also faces the input end of the mass transfer device, and the imaging observation component is located above the mass transfer device; the light output direction of the illumination optical path component also faces the input end of the mass transfer device; the light output directions of the mask projection component, the imaging observation component, and the illumination optical path component share a common optical path. The common optical path design reduces the number of optical lenses, lowers manufacturing costs, and allows for a more compact optical path layout in mass transfer equipment, reducing equipment size. The stage 96 adjustment system, based on the MicroLED transfer state, integrates the mass transfer device, imaging observation component, mask projection component, and illumination optical path component. The illumination optical path can use monochromatic point light sources such as blue or green, which, after passing through the illumination lens group 74 and the projection lens group 72, can provide approximately uniform illumination to the working surface 90, laying the foundation for accurate imaging. The core highlight is the common optical path design, which ensures that the light output direction of the three types of components is consistent, reducing the number of optical lenses, lowering manufacturing costs, and making the optical path layout more compact, effectively reducing equipment size. The imaging observation component, located above the mass transfer device, can accurately collect imaging data. Combined with the adjustment logic triggered by the transfer state, it provides reliable support for the precise adjustment of the stage 96 without interfering with the efficient mass transfer process, helping to improve the alignment accuracy of the MicroLED chip die 92 and electrode 95, thus laying a solid hardware foundation for improved transfer yield.

[0094] The mass transfer device includes multiple MicroLED chip dies 92. A mask projection component projects a rectangular hole array pattern on a mask onto the location of the MicroLED chip dies 92 on a transparent carrier substrate 91. The transparent carrier substrate 91 is generally a sapphire glass substrate. LED chip structures can be directly grown on the transparent carrier substrate 91 through vapor deposition or photolithography, and then transferred to a target substrate 94. Each rectangular hole corresponds to one MicroLED chip die 92. In actual operation, the relative distance between the target substrate 94 and the transparent carrier substrate 91 is only tens of micrometers. The imaging observation component can simultaneously record the image information of the MicroLED chip dies 92 and electrodes 95 in a single imaging. A stage 96 and multiple electrodes 95 are included. The target substrate 94 is placed on the stage 96, and the multiple electrodes 95 are distributed on the target substrate 94. Multiple MicroLED chips are arrayed on the transparent carrier substrate. The MicroLED chip dies 92 are located above the electrodes 95. A transfer position is formed between any two adjacent electrodes 95. The transfer position is used to carry the MicroLED chip dies 92. The stage 96 has X, Y, and Z axis displacement and rotation functions to adjust the relative position of the target substrate 94 and the transparent carrier substrate 91. In actual operation, each laser pulse corresponds to a large number of MicroLED chip dies 92 being transferred. The light output direction of the mask projection component, the light output direction of the imaging observation component, and the light output direction of the illumination optical path component are all directed toward the MicroLED chip dies 92. The mask projection component is used to provide laser pulse irradiation to the MicroLED chip dies 92. Under laser pulse irradiation, the MicroLED chip dies 92 are transferred from the transparent carrier substrate 91 to their respective transfer positions.

[0095] The imaging optical path consists of a working surface 90, a rear projection lens group 72, a first beam splitter 81, a second beam splitter 82, a front imaging objective lens group 73, and a camera 100. The front imaging objective lens group 73 and the rear projection lens group 72 together form the imaging lens, which images the real-time working conditions at the working surface 90 onto the sensor of the camera 100. The mask projection assembly includes a laser 10, which typically uses an ultraviolet excimer laser source with a typical wavelength of 248nm or 266nm. Its emitted light spot shape is approximately rectangular, and the length and width directions of the light spot are usually referred to as the major axis and minor axis. After all the above position calibration steps are completed, the laser 10 can be controlled to emit laser pulses for the mass transfer process. Beam attenuation module 20... The energy of the beam emitted from laser 10 entering the subsequent optical path system can be adjusted. The beam expander module 40 can adjust the major and minor axis dimensions of the beam emitted from laser 10 to match the subsequent optical path. The first reflector 31, the beam expander module 40, and the second reflector 32 are only used to change the direction of the optical path to make the optical path layout more compact. In actual laser mass transfer equipment, the number of reflectors, homogenization and shaping module 50, mask 60, front group 71 of projection lens, first beam splitter 81, and rear group 72 of projection lens can be increased or decreased according to the actual structural layout. The homogenization and shaping module 50 can homogenize the major and minor axes of the light spot to generate a large rectangular uniform light spot, which illuminates the mask. On the substrate 60, rectangular holes are arrayed on the mask 60. The front group 71 and the rear group 72 of the projection lens together form a mask projection lens, projecting the pattern on the mask 60 onto the working surface 90 in a proportionally reduced manner. The transparent carrier substrate 91 has a densely arrayed array of MicroLED chip dies 92 to be transferred. Each rectangular hole on the mask 60 corresponds to a laser beam after passing through the projection lens, and each laser beam exactly covers one MicroLED chip die 92. After being irradiated by the laser beam, the MicroLED chip die 92 can detach from the transparent carrier substrate 91 and fall onto the corresponding transfer position on the target substrate 94. The light emission direction of the laser 10 is towards the beam attenuation module 20. At the input end, the light output direction of the beam attenuation module 20 is towards the input end of the first reflector 31, the light output direction of the first reflector 31 is towards the input end of the beam expander 40, the light output direction of the beam expander 40 is towards the input end of the second reflector 32, and the light output direction of the second reflector 32 is towards the input end of the homogenization and shaping module 50. The homogenization and shaping module 50, the mask 60, and the front group 71 of the projection lens are coaxially arranged. The light output direction of the homogenization and shaping module 50 is towards the input end of the mask 60, the light output direction of the mask 60 is towards the input end of the front group 71 of the projection lens, and the light output direction of the front group 71 of the projection lens is towards the input end of the first beam splitter 81.The light output direction of the first beam splitter 81 is towards the input end of the rear group 72 of the projection lens; the light output direction of the rear group 72 of the projection lens is towards the input end of the mass transfer device; the mask 60 is provided with an array of rectangular holes, and the multiple rectangular holes allow the laser beam passing through them to be projected onto the mass transfer device in a proportionally reduced manner. The number of MicroLED chip dies 92 transferred at one time is the same as the number of rectangular holes on the mask 60. After each transfer is completed, the stage 96 will move horizontally once and switch to the adjacent working area for the next transfer. The laser mass transfer device based on the mask projection scheme can transfer multiple MicroLED chip dies 92 from the transparent carrier substrate 91 to the target substrate 94 under a single laser pulse irradiation, with extremely high transfer efficiency. By replacing the mask 60 with different rectangular hole distribution patterns, selective transfer of MicroLED chip dies 92 of different models and specifications can be achieved.

[0096] In this embodiment, the mass transfer device in the system precisely matches the transfer positions of the MicroLED chip dies 92 on the transparent carrier substrate 91 with those on the target substrate 94. Combined with a stage 96 equipped with X, Y, and Z-axis displacement and rotation functions, the relative positions of the substrates can be flexibly adjusted, providing structural support for alignment. The mask projection component uses an ultraviolet excimer laser, which, after beam expansion and homogenization, projects through the array of holes in the mask template 60. A single laser pulse can transfer the MicroLED chip dies 92 with the same number of holes, resulting in extremely high transfer efficiency. By changing the mask template 60 with different hole patterns, selective transfer of dies of different specifications can be achieved, demonstrating strong adaptability. The imaging optical path can simultaneously record images of the dies and electrodes 95, providing data support for precise adjustments. Combined with optimized layout of the optical path reflectors, the structure is more compact. After one transfer, the stage 96 horizontally switches to an adjacent area for continuous and efficient operation. The overall design requires no complex new hardware, balancing high throughput and high compatibility, reducing industrialization costs, and helping to improve transfer yield and the feasibility of large-scale applications.

[0097] Figure 9This is a schematic diagram of the structure of a workbench adjustment device 900 based on MicroLED transfer state provided in an embodiment of the present invention. The workbench adjustment device 900 based on MicroLED transfer state can vary significantly due to different configurations or performance. It may include one or more central processing units (CPUs) 910 (e.g., one or more processors) and a memory 920, and one or more storage media 930 (e.g., one or more mass storage devices) storing application programs 933 or data 932. The memory 920 and storage media 930 can be temporary or persistent storage. The program stored in the storage media 930 may include one or more modules (not shown in the diagram), each module may include a series of instruction operations on the workbench adjustment device 900 based on MicroLED transfer state. Furthermore, the processor 910 may be configured to communicate with the storage media 930 and execute a series of instruction operations in the storage media 930 on the workbench adjustment device 900 based on MicroLED transfer state to implement the steps of the workbench adjustment method based on MicroLED transfer state provided in the above-described method embodiments.

[0098] The workbench adjustment device 900 based on MicroLED transfer state may also include one or more power supplies 940, one or more wired or wireless network interfaces 950, one or more input / output interfaces 960, and one or more operating systems 931, such as Windows Server, MacOSX, Unix, Linux, FreeBSD, etc. Those skilled in the art will understand that... Figure 9 The structure of the worktable adjustment device 900 based on the MicroLED transfer state shown does not constitute a limitation on the worktable adjustment device 900 based on the MicroLED transfer state. It may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0099] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the device or unit described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0100] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0101] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A worktable adjustment method based on a Micro LED transfer state, characterized in that, The application is applied to a workbench adjustment system based on a MicroLED transfer state, the workbench adjustment system based on the MicroLED transfer state comprises a workbench and an imaging observation assembly, the workbench is provided with a work area, and the workbench adjustment method based on the MicroLED transfer state comprises: An actual size of the work area is acquired, and the work area is divided according to a preset imaging field of view requirement and the actual size to obtain region division data; An intermediate region is obtained from the region division data; The workbench is controlled to move longitudinally, and imaging data of the intermediate region is acquired by the imaging observation assembly to obtain an imaging data sequence; The imaging data sequence is analyzed according to a preset image sharpness evaluation function to obtain a corresponding relationship; The imaging data sequence is analyzed according to the image sharpness evaluation function to obtain sharpness value data; Work distance data is obtained by mapping the imaging data sequence; The corresponding relationship is constructed according to the sharpness value data and the work distance data; The MicroLED transfer state is determined according to the corresponding relationship; The workbench is adjusted according to a preset verification condition and the MicroLED transfer state; The workbench is adjusted according to a preset verification condition and the MicroLED transfer state, comprising: The MicroLED transfer state is analyzed; When the MicroLED transfer state is a one-time transfer completion, current imaging data of the intermediate region is acquired by the imaging observation assembly to obtain first imaging data; A left region and a right region are obtained from the region division data according to a preset optimal work distance range; The workbench is adjusted according to the verification condition, the first imaging data, the left region and the right region; The workbench adjustment system based on the MicroLED transfer state further comprises a plurality of electrodes, and the workbench is adjusted according to the verification condition, the first imaging data, the left region and the right region, comprising: The left region and the right region are analyzed according to a preset difference threshold to obtain an inclination angle; The workbench is adjusted according to the inclination angle; Second imaging data of the left region is acquired by the imaging observation assembly; Third imaging data of the right region is acquired by the imaging observation assembly; Feature analysis results and a degree of offset are obtained by performing feature analysis on the first imaging data, the second imaging data and the third imaging data according to a preset image automatic recognition algorithm; It is judged whether the feature analysis results meet a verification condition that electrodes cannot be observed; If the feature analysis results do not meet the verification condition that electrodes cannot be observed, the workbench is adjusted according to the degree of offset, and the imaging data of the intermediate region is acquired by the imaging observation assembly until the feature analysis results meet the verification condition that electrodes cannot be observed. The left region is obtained to obtain a left distance. 2.The Micro LED transfer state-based worktable adjustment method of claim 1, wherein, ​ ​ Obtain the working distance of the right region to obtain the right distance; Calculate the difference value according to the left distance and the right distance to obtain the distance difference value; Determine whether the distance difference value is greater than or less than the difference value threshold; When the distance difference value is greater than or less than the difference value threshold, obtain the horizontal distance between the left region and the right region; According to the preset inclination angle, the distance difference value and the horizontal distance are approximately calculated by the formula to obtain the inclination angle. 3.The Micro LED transfer state-based worktable adjustment method of claim 1, wherein, The left region and the right region are obtained from the region division data according to the preset optimal working distance range, including: According to the image sharpness evaluation function, analyze the first imaging data to obtain the sharpness value; According to the sharpness value, the working distance is obtained from the corresponding relationship; Determine whether the working distance is within the optimal working distance range; When the working distance is within the optimal working distance range, the left region and the right region are obtained from the region division data.

4. A stage adjustment system based on MicroLED transfer status, characterized in that, The workbench adjustment method based on the MicroLED transfer state is executed as claimed in any one of claims 1-3, the workbench adjustment system based on the MicroLED transfer state includes a mass transfer device, an imaging observation assembly, a mask projection assembly, and an illumination light path assembly, the light output direction of the mask projection assembly is towards the input end of the mass transfer device; the light output direction of the imaging observation assembly is towards the input end of the mass transfer device, and the imaging observation assembly is located above the mass transfer device; the light output direction of the illumination light path assembly is towards the input end of the mass transfer device; the light output direction of the mask projection assembly, the light output direction of the imaging observation assembly, and the light output direction of the illumination light path assembly are in the same light path. 5.The MicroLED transfer state based worktable adjustment system of claim 4, wherein, The mass transfer device includes a plurality of MicroLED chip grains, a transparent carrier substrate, a target substrate, a workbench, and a plurality of electrodes, the target substrate is provided on the workbench, and a plurality of electrodes are distributed on the target substrate; a plurality of MicroLED chip grains are arrayed on the transparent carrier substrate, and each of the plurality of MicroLED chip grains is located above the plurality of electrodes, and a transfer site is formed between any two adjacent electrodes, the transfer site is used to carry the MicroLED chip grain; the light output direction of the mask projection assembly, the light output direction of the imaging observation assembly, and the light output direction of the illumination light path assembly are all towards the plurality of MicroLED chip grains, and the mask projection assembly is used to provide laser pulse irradiation to the plurality of MicroLED chip grains, and under the laser pulse irradiation, the plurality of MicroLED chip grains are transferred from the transparent carrier substrate to the corresponding transfer site. 6.The Micro LED transfer state-based worktable adjustment system of claim 4, wherein, The mask projection assembly comprises a laser, a beam attenuation module, a first mirror, a beam expansion module, a second mirror, a homogenization and shaping module, a mask plate, a front group of projection lenses, a first beam splitter and a rear group of projection lenses; the light output direction of the laser is towards the input end of the beam attenuation module, the light output direction of the beam attenuation module is towards the input end of the first mirror, the light output direction of the first mirror is towards the input end of the beam expansion module, the light output direction of the beam expansion module is towards the input end of the second mirror, the light output direction of the second mirror is towards the input end of the homogenization and shaping module, the homogenization and shaping module, the mask plate and the front group of projection lenses are coaxially arranged; the light output direction of the homogenization and shaping module is towards the input end of the mask plate, the light output direction of the mask plate is towards the input end of the front group of projection lenses, and the light output direction of the front group of projection lenses is towards the input end of the first beam splitter; the light output direction of the first beam splitter is towards the input end of the rear group of projection lenses; the light output direction of the rear group of projection lenses is towards the input end of the mass transfer device; a plurality of rectangular holes are arranged in an array on the mask plate, and the plurality of rectangular holes project the laser beam passing therethrough in a manner of equal proportion reduction to form an image on the mass transfer device.

7. A stage adjustment apparatus based on a MicroLED transfer state, characterized by, Comprise: a memory and at least one processor, the memory having instructions stored therein; at least one of the processors invokes the instructions in the memory to cause the MicroLED transfer state-based workbench adjustment device to perform the steps of the MicroLED transfer state-based workbench adjustment method according to any one of claims 1-3.

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