Preparation method of LED display screen mask

Abstract

The invention discloses a preparation method of an LED display screen mask, and relates to the technical field of LED display screen mask preparation, and the preparation method comprises the following steps: blending polycarbonate resin and macromolecular color masterbatch according to a preset proportion, and then preparing a body pre-colored PC sheet through a co-extrusion process; carrying out uniaxial pre-stress directional stretching treatment on the obtained body pre-colored PC sheet to obtain a stretched sheet with enhanced dimensional stability; a stamping die with the cutter point angle being 86.2 degrees and a Teflon-diamond-like carbon composite coating arranged on the surface of a cutter edge is adopted, and multi-stage temperature control gradient stamping is conducted on the stretched sheet; in the multi-stage temperature control gradient stamping process, a single-piece mask is obtained through repeated jump stamping forming, sixty thousands of, two hundred and seventy-two micropores are formed in the single-piece mask, the micropores are square, and the side length of the micropores and the distance between every two adjacent micropores are controlled within the tolerance range of + / -0.02 mm; and the micro-vibration auxiliary demolding mechanism and the hanging mode pressure self-balancing device are synchronously started in the stamping process.

Description

Technical Field

[0001] This invention relates to the field of LED display screen mask manufacturing technology, and in particular to a method for manufacturing an LED display screen mask. Background Technology

[0002] LED display screen mask manufacturing technology refers to the complete set of processes used to manufacture precision optical structural components (i.e., "masks") that cover LED chips and serve to shield, prevent glare, mix light, and provide protection. These masks are typically thin sheet structures with micro-holes that correspond one-to-one with the LED chips, and their performance directly affects the display screen's contrast ratio, color consistency, viewing angle, and outdoor reliability.

[0003] Traditional LED masks are injection molded and then painted. Due to uneven paint thickness, batch differences in raw materials, and environmental factors, there are obvious color differences between different masks on the same display screen or between the mask and the PCB / lamp board. This manifests as white edges, black edges, or inconsistent overall color tone, which seriously affects the display effect. Furthermore, due to the low dimensional accuracy of injection molded parts and the ease with which the edges are deformed, physical gaps are unavoidable when multiple masks are spliced ​​together. When the LEDs are lit, these gaps will form obvious white lines, black lines, light leakage, or uneven brightness, and may even cause screen splitting at different viewing angles, which seriously damages the integrity of the image and the viewing experience. Summary of the Invention

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

[0005] Therefore, this invention provides a method for preparing LED display screen masks to solve the problem that traditional masks are made by injection molding and then spraying oil on the surface for coloring. Due to uneven oil spraying thickness, batch differences in raw materials, and environmental factors, there are obvious color differences between different masks on the same display screen or between the mask and the PCB / lamp board, which manifest as white edges, black edges, or inconsistent overall color tone, seriously affecting the display effect.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: In a first aspect, the present invention provides a method for preparing an LED display screen mask, comprising: Pre-colored PC sheets are prepared by blending polycarbonate resin and polymer masterbatch in a preset ratio and then co-extruding them. The obtained pre-colored PC sheet was subjected to uniaxial prestressed directional stretching treatment to obtain a stretched sheet with enhanced dimensional stability. A stamping die with a blade angle of 86.2 degrees and a Teflon-diamond-like composite coating on the blade surface is used to perform multi-stage temperature-controlled gradient stamping on the stretched sheet. In the multi-stage temperature-controlled gradient stamping process, a single-piece mask is obtained through multiple skip-stamping processes. The single-piece mask has 6,272 micro-holes, which are square in shape. The side length of the micro-holes and the spacing between adjacent micro-holes are controlled within a tolerance range of ±0.02 mm. During the stamping process, the micro-vibration assisted demolding mechanism and the hanging pattern pressure self-balancing device are activated simultaneously to keep the mold in a dynamic pressure release state, thereby obtaining a mask structure with no edge collapse or folding. A machine vision system is used to detect the position of micro-holes in the stamped face mask in real time, and the detection results are fed back to the stamping positioning system to correct subsequent stamping actions, ensuring stable micro-hole position accuracy. The mask units, after being corrected for positional accuracy, are spliced ​​together. The flexibility of the materials enables a seamless fit at the splicing interface, eliminating light leakage and optical discontinuities at the seams.

[0007] In a preferred embodiment of the method for preparing the LED display screen mask of the present invention, the specific steps of preparing a pre-colored PC sheet by co-extrusion of polycarbonate resin and polymer masterbatch in a preset ratio are as follows: Blue masterbatch, red masterbatch, and black masterbatch are mixed with polycarbonate resin in a high-speed mixer at a mass percentage ratio of 60%, 20%, and 15%, respectively. The mixture is then fed into a twin-screw co-extrusion unit and extruded through a die in a molten state to form a continuous sheet with a thickness of 0.8 mm to 1.2 mm. After cooling and setting, the sheet is wound up to obtain a pre-colored PC sheet with uniform color that is optically matched to LED light boards and PCB boards.

[0008] As a preferred embodiment of the method for preparing the LED display screen mask according to the present invention, the step of performing uniaxial prestressed directional tensile treatment on the obtained pre-colored PC sheet specifically includes: The pre-colored PC sheet after winding is fed into a constant temperature stretching equipment. It is stretched unidirectionally at a stretch ratio of 1.05 to 1.15 times along the machine direction at a temperature of 135°C to 145°C. Then it is rapidly cooled by cooling rollers to fix the molecular chain orientation, thereby improving the dimensional stability of the material in the subsequent stamping process and suppressing springback deformation.

[0009] As a preferred embodiment of the method for preparing the LED display screen mask according to the present invention, the stamping die with a blade angle of 86.2 degrees and a Teflon-diamond-like composite coating on the blade surface specifically includes: The cutting edge of the stamping die is precision ground to an angle of 86.2 degrees, and a bottom layer of Teflon coating and a top layer of diamond-like carbon film are deposited sequentially on its surface to form a composite coating structure. The composite coating structure reduces material adhesion resistance and keeps the cutting edge sharp for a long time, avoiding burrs or collapse at the hole edge due to residual adhesive during the punching process.

[0010] As a preferred embodiment of the method for preparing the LED display mask according to the present invention, the step of obtaining a single mask through multiple skip-punching during a multi-level temperature-controlled gradient stamping process specifically includes: The stretched PC sheet is placed in a punching die with 224, 448 or 112 cavities. Select 14, 28 or 56 skip-stroke cycles according to the target mask size. Control the mold temperature in segments within the range of 80℃ to 100℃ during each stamping to gradually release the internal stress of the material during each stamping. The final product is a 250 mm × 125 mm mask base with 6,272 square micropores precisely arranged on it.

[0011] As a preferred embodiment of the method for manufacturing the LED display screen cover according to the present invention, wherein: the simultaneous activation of the micro-vibration assisted demolding mechanism and the hanging mold pressure self-balancing device during the stamping process specifically includes: A high-frequency micro-amplitude vibration unit with a frequency of 200 Hz to 500 Hz and an amplitude of 0.02 mm to 0.05 mm is installed between the press slide and the die. At the same time, the die is installed on a floating die holder so that the stamping reaction force is released through the elastic buffer of the holder, avoiding local overpressure that could cause the mask edge to warp or break.

[0012] In a preferred embodiment of the method for manufacturing the LED display mask according to the present invention, the step of using a machine vision system to detect the position of the micro-holes in the stamped mask in real time and feeding the detection results back to the stamping positioning system to correct subsequent stamping actions specifically includes: A high-resolution industrial camera and image processing unit are set up downstream of the stamping station. After each jump punch, the center coordinates of the microholes in the current mask area are identified, and the deviation between the actual position and the theoretical design position is calculated. The deviation value is dynamically adjusted by the servo control system to adjust the displacement of the XY axis positioning platform for the next stamping, thereby achieving closed-loop compensation.

[0013] As a preferred embodiment of the method for preparing the LED display mask according to the present invention, the step of splicing the mask units after positional accuracy correction, and achieving seamless bonding of the splicing interface by relying on material flexibility, specifically includes: After all the stamping and testing is completed, the mask unit is cut along the module boundary and directly attached to the surface of the LED light board. Adjacent masks naturally fit together in the physical contact area due to the thermoplasticity and elastic deformation capability of polycarbonate material, without the need for additional sealant or mechanical fasteners. The seam width is less than 0.01 mm, and no visible white lines, black edges or brightness differences are produced when the LED is lit.

[0014] As a preferred embodiment of the preparation method of the LED display mask of the present invention, in the process of blending the polymer masterbatch and polycarbonate resin, an anti-ultraviolet stabilizer with a mass fraction of 0.3% to 0.8% and a heat stabilizer with a mass fraction of 0.2% to 0.5% are also added to improve the weather resistance and color stability of the obtained mask in the long-term outdoor use environment.

[0015] In a preferred embodiment of the preparation method of the LED display mask of the present invention, the UV stabilizer is a hindered amine light stabilizer and the heat stabilizer is an organophosphate compound. The two are uniformly dispersed in the polycarbonate matrix during the co-extrusion melt stage, so that after the mask is continuously aged for 1000 hours at 85°C and 85% relative humidity, the color difference is less than 1.5 and there is no obvious yellowing or deterioration of mechanical properties.

[0016] The beneficial effects of this invention are as follows: By organically integrating technologies such as co-extrusion pre-coloring of polymer masterbatch and polycarbonate resin, uniaxial prestressed directional stretching, multi-stage temperature-controlled gradient stamping and Teflon-diamond-like composite coating mold coordination, micro-vibration assisted demolding and pressure self-balancing, machine vision online feedback compensation, and flexible seamless splicing, this invention achieves simultaneous breakthroughs in three aspects of LED display mask: material body color consistency, micro-hole forming precision, and splicing optical continuity. It effectively solves the problems of color batch differences, brittle fracture, and white lines / black edges and viewing angle splitting caused by light leakage from splicing seams in traditional injection-molded masks, and improves the optical uniformity, assembly efficiency, and weather resistance reliability of the display screen for long-term outdoor use. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart illustrating the preparation method of an LED display screen cover. Detailed Implementation

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0020] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0021] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0022] Reference Figure 1 As one embodiment of the present invention, this embodiment provides a method for preparing an LED display screen mask, comprising: S1. Polycarbonate resin and polymer masterbatch are blended in a preset ratio and then co-extruded to obtain pre-colored PC sheets.

[0023] Furthermore, blue masterbatch, red masterbatch, and black masterbatch are mixed with polycarbonate resin in a high-speed mixer at a mass percentage ratio of 60%, 20%, and 15%, respectively. The mixture is then fed into a twin-screw co-extrusion unit and extruded through a die in a molten state to form a continuous sheet with a thickness of 0.8 mm to 1.2 mm. After cooling and setting, the sheet is wound up to obtain a pre-colored PC sheet with uniform color that is optically matched to LED light boards and PCB boards.

[0024] During the blending process of polymer masterbatch and polycarbonate resin, 0.3% to 0.8% by mass of UV stabilizer and 0.2% to 0.5% by mass of heat stabilizer are added to improve the weather resistance and color stability of the resulting mask under long-term outdoor use. The UV stabilizer is a hindered amine light stabilizer and the heat stabilizer is an organophosphate compound. The two are uniformly dispersed in the polycarbonate matrix during the co-extrusion melt stage, so that after the mask is continuously aged for 1000 hours at 85°C and 85% relative humidity, the color difference is less than 1.5 and there is no obvious yellowing or deterioration of mechanical properties.

[0025] It should be noted that the co-extrusion pre-coloring process used in this step allows the color to be directly integrated into the material itself, rather than being sprayed on the surface or dyed later. This fundamentally avoids visual inconsistencies caused by coating peeling or batch color differences. At the same time, by precisely controlling the color masterbatch ratio and adding specific weather-resistant additives, the mask is ensured to maintain stable optical performance during long-term outdoor use, meeting the stringent requirements of high-reliability LED displays for color consistency and environmental tolerance.

[0026] S2. The obtained pre-colored PC sheet is subjected to uniaxial prestressed directional stretching treatment to obtain a stretched sheet with enhanced dimensional stability.

[0027] Furthermore, the pre-colored PC sheet after winding is fed into a constant temperature stretching equipment, where it is stretched unidirectionally at a stretch ratio of 1.05 to 1.15 times along the machine direction at a temperature of 135°C to 145°C. Then, it is rapidly cooled by cooling rollers to fix the molecular chain orientation, thereby improving the dimensional stability of the material in the subsequent stamping process and suppressing springback deformation.

[0028] It should be noted that uniaxial prestressed directional stretching treatment not only effectively reduces the elastic rebound of PC sheets in subsequent stamping, but also significantly improves the mechanical isotropy and dimensional stability of the material by inducing the molecular chains to align in an orderly manner along the stretching direction, providing a structural basis for achieving micron-level hole position accuracy and overall flatness of large-size masks.

[0029] S3. A stamping die with a blade angle of 86.2 degrees and a Teflon-diamond-like composite coating on the blade surface is used to perform multi-stage temperature-controlled gradient stamping on the stretched sheet.

[0030] Furthermore, the cutting edge of the stamping die is precision ground to an 86.2-degree angle, and a bottom layer of Teflon coating and a top layer of diamond-like carbon film are deposited sequentially on its surface to form a composite coating structure. The composite coating structure reduces material adhesion resistance and keeps the cutting edge sharp for a long time, avoiding burrs or collapse at the hole edge due to residual adhesive during punching.

[0031] It should be noted that the 86.2-degree cutting edge angle, combined with the design of the Teflon-diamond-like composite coating, balances the cutting sharpness and the smoothness of demolding: too small an angle can easily lead to chipping of the cutting edge, while too large an angle will increase the shearing resistance; the composite coating utilizes the low surface energy of Teflon to reduce adhesion, and relies on the high hardness of diamond-like carbon to maintain the cutting edge life, thereby ensuring that the edges of the microholes are smooth and burr-free during high-speed continuous stamping.

[0032] S4. In the multi-stage temperature-controlled gradient stamping process, a single-piece mask is obtained through multiple skip-stamping processes. Six thousand two hundred and seventy-two micro-holes are formed on the single-piece mask. The micro-holes are square in shape, and the side length of the micro-holes and the spacing between adjacent micro-holes are controlled within the tolerance range of ±0.02 mm.

[0033] Furthermore, the stretched PC sheet is placed in a punching die with 224, 448, or 112 cavities. Select 14, 28 or 56 skip-stroke cycles according to the target mask size. Control the mold temperature in segments within the range of 80℃ to 100℃ during each stamping to gradually release the internal stress of the material during each stamping. The final product is a 250 mm × 125 mm mask base with 6,272 square micropores precisely arranged on it.

[0034] It should be noted that the coordinated control of multi-level temperature control and the number of punches is the key to achieving the precision forming of high-density micro-hole arrays. Segmented temperature control avoids local heat accumulation that causes material softening and deformation, while multiple punches gradually release internal stress to prevent hole position displacement or hole shape distortion caused by one-time punching, ultimately ensuring that more than 6,000 micro-holes maintain a high degree of positional consistency on a large-area mask.

[0035] S5. During the stamping process, the micro-vibration-assisted demolding mechanism and the hanging mold pressure self-balancing device are activated simultaneously to keep the mold in a dynamic pressure release state, thereby obtaining a mask structure with no edge collapse or folding.

[0036] Furthermore, a high-frequency micro-amplitude vibration unit is installed between the press slide and the die, with a frequency of 200 Hz to 500 Hz and an amplitude of 0.02 mm to 0.05 mm. At the same time, the die is installed on a floating die holder, so that the stamping reaction force is released through the elastic buffer of the holder, avoiding local overpressure that could cause the mask edge to warp or break.

[0037] It should be noted that the micro-vibration assisted demolding and the hanging mold pressure self-balancing device together constitute a dynamic force control system, which realizes material peeling and reaction force buffering simultaneously during stamping, effectively eliminating edge collapse, warping or micro-cracks caused by stress concentration in traditional rigid molds, and is especially suitable for the molding of large-area thin-walled structures of high-toughness PC materials.

[0038] S6. Use a machine vision system to detect the position of the micro-holes in the stamped mask in real time, and feed the detection results back to the stamping positioning system to correct subsequent stamping actions and ensure stable micro-hole position accuracy.

[0039] Furthermore, a high-resolution industrial camera and image processing unit are set up downstream of the stamping station. After each punching cycle, the coordinates of the micro-hole center in the current mask area are identified, and the deviation between the actual position and the theoretical design position is calculated. The deviation value is dynamically adjusted by the servo control system to adjust the displacement of the XY axis positioning platform for the next stamping, thereby achieving closed-loop compensation.

[0040] It should be noted that the closed-loop linkage between machine vision and servo positioning system upgrades traditional offline sampling inspection to online full inspection + real-time correction, so that the micro-hole position error is compensated before it accumulates. This not only ensures that the hole position tolerance of a single mask is ≤±0.02mm, but also ensures that the hole array is continuously aligned when multiple masks are spliced, providing a geometric basis for the optical uniformity of the entire screen.

[0041] S7. The mask units, after being corrected for positional accuracy, are spliced ​​together. The splicing interface is seamlessly fitted by relying on the flexibility of the material, eliminating light leakage and optical discontinuity at the splicing seams.

[0042] Furthermore, after all the stamping and testing is completed, the mask unit is cut along the module boundary and directly attached to the surface of the LED light board. Adjacent masks naturally fit together in the physical contact area due to the thermoplasticity and elastic deformation capability of polycarbonate material, without the need for additional sealant or mechanical fasteners. The seam width is less than 0.01 mm, and no visible white lines, black edges or brightness differences are produced when the LED is lit.

[0043] It should be noted that this invention abandons the traditional mechanical splicing method that relies on adhesives or clips, and instead utilizes the moderate flexibility of PC material at room temperature and the intermolecular forces at the interface to achieve physical contact and adaptive bonding. The width of the splicing seam is controlled within the range that is indistinguishable to the human eye, fundamentally eliminating light leakage paths and differences in optical refraction, and achieving a truly seamless display.

[0044] In summary, this invention organically integrates various technologies such as co-extrusion pre-coloring of polymer masterbatch and polycarbonate resin, uniaxial prestressed directional stretching, multi-stage temperature-controlled gradient stamping and Teflon-diamond-like composite coating mold coordination, micro-vibration assisted demolding and pressure self-balancing, machine vision online feedback compensation, and flexible seamless splicing. This achieves simultaneous breakthroughs in three aspects for LED display screen masks: material body color consistency, micropore forming precision, and splicing optical continuity. It effectively solves the problems of color batch differences, brittle fracture, and white lines / black edges and viewing angle splitting caused by light leakage at the splicing seams in traditional injection-molded masks, improving the optical uniformity, assembly efficiency, and weather resistance reliability of the display screen for long-term outdoor use.

[0045] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for preparing an LED display screen mask, characterized in that: include: Pre-colored PC sheets are prepared by blending polycarbonate resin and polymer masterbatch in a preset ratio and then co-extruding them. The obtained pre-colored PC sheet was subjected to uniaxial prestressed directional stretching treatment to obtain a stretched sheet with enhanced dimensional stability. A stamping die with a blade angle of 86.2 degrees and a Teflon-diamond-like composite coating on the blade surface is used to perform multi-stage temperature-controlled gradient stamping on the stretched sheet. In the multi-stage temperature-controlled gradient stamping process, a single-piece mask is obtained through multiple skip-stamping processes. The single-piece mask has 6,272 micro-holes, which are square in shape. The side length of the micro-holes and the spacing between adjacent micro-holes are controlled within a tolerance range of ±0.02 mm. During the stamping process, the micro-vibration assisted demolding mechanism and the hanging pattern pressure self-balancing device are activated simultaneously to keep the mold in a dynamic pressure release state, thereby obtaining a mask structure with no edge collapse or folding. A machine vision system is used to detect the position of micro-holes in the stamped face mask in real time, and the detection results are fed back to the stamping positioning system to correct subsequent stamping actions, ensuring stable micro-hole position accuracy. The mask units, after being corrected for positional accuracy, are spliced ​​together. The flexibility of the materials enables a seamless fit at the splicing interface, eliminating light leakage and optical discontinuities at the seams.

2. The method for preparing the LED display screen mask as described in claim 1, characterized in that: The specific steps for preparing pre-colored PC sheets by blending polycarbonate resin and polymer masterbatch in a preset ratio and then co-extruding them are as follows: Blue masterbatch, red masterbatch, and black masterbatch are mixed with polycarbonate resin in a high-speed mixer at a mass percentage ratio of 60%, 20%, and 15%, respectively. The mixture is then fed into a twin-screw co-extrusion unit and extruded through a die in a molten state to form a continuous sheet with a thickness of 0.8 mm to 1.2 mm. After cooling and setting, the sheet is wound up to obtain a pre-colored PC sheet with uniform color that is optically matched to LED light boards and PCB boards.

3. The method for preparing the LED display screen mask as described in claim 2, characterized in that: The uniaxial prestressed directional stretching treatment of the obtained pre-colored PC sheet specifically includes: The pre-colored PC sheet after winding is fed into a constant temperature stretching equipment. It is stretched unidirectionally at a stretch ratio of 1.05 to 1.15 times along the machine direction at a temperature of 135°C to 145°C. Then it is rapidly cooled by cooling rollers to fix the molecular chain orientation, thereby improving the dimensional stability of the material in the subsequent stamping process and suppressing springback deformation.

4. The method for preparing the LED display screen mask as described in claim 3, characterized in that: The stamping die employing a cutting edge angle of 86.2 degrees and a Teflon-diamond-like composite coating on the cutting edge surface specifically includes: The cutting edge of the stamping die is precision ground to an angle of 86.2 degrees, and a bottom layer of Teflon coating and a top layer of diamond-like carbon film are deposited sequentially on its surface to form a composite coating structure. The composite coating structure reduces material adhesion resistance and keeps the cutting edge sharp for a long time, avoiding burrs or collapse at the hole edge due to residual adhesive during the punching process.

5. The method for preparing the LED display screen mask as described in claim 4, characterized in that: The process of obtaining a single-piece mask through multiple skip-stroke forming during multi-level temperature-controlled gradient stamping specifically includes: The stretched PC sheet is placed in a punching die with 224, 448 or 112 cavities. Select 14, 28 or 56 skip-stroke cycles according to the target mask size. Control the mold temperature in segments within the range of 80℃ to 100℃ during each stamping to gradually release the internal stress of the material during each stamping. The final product is a 250 mm × 125 mm mask base with 6,272 square micropores precisely arranged on it.

6. The method for preparing the LED display screen mask as described in claim 5, characterized in that: The simultaneous activation of the micro-vibration-assisted demolding mechanism and the hanging mold pressure self-balancing device during the stamping process specifically includes: A high-frequency micro-amplitude vibration unit with a frequency of 200 Hz to 500 Hz and an amplitude of 0.02 mm to 0.05 mm is installed between the press slide and the die. At the same time, the die is installed on a floating die holder so that the stamping reaction force is released through the elastic buffer of the holder, avoiding local overpressure that could cause the mask edge to warp or break.

7. The method for preparing the LED display screen mask as described in claim 6, characterized in that: The process of using a machine vision system to detect the position of micro-holes in the stamped mask in real time and feeding the detection results back to the stamping positioning system to correct subsequent stamping actions specifically includes: A high-resolution industrial camera and image processing unit are set up downstream of the stamping station. After each jump punch, the center coordinates of the microholes in the current mask area are identified, and the deviation between the actual position and the theoretical design position is calculated. The deviation value is dynamically adjusted by the servo control system to adjust the displacement of the XY axis positioning platform for the next stamping, thereby achieving closed-loop compensation.

8. The method for preparing the LED display screen mask as described in claim 7, characterized in that: The process of splicing together the mask units after positional accuracy correction, relying on material flexibility to achieve seamless bonding of the splicing interface, specifically includes: After all the stamping and testing is completed, the mask unit is cut along the module boundary and directly attached to the surface of the LED light board. Adjacent masks naturally fit together in the physical contact area due to the thermoplasticity and elastic deformation capability of polycarbonate material, without the need for additional sealant or mechanical fasteners. The seam width is less than 0.01 mm, and no visible white lines, black edges or brightness differences are produced when the LED is lit.

9. The method for preparing the LED display screen mask as described in claim 8, characterized in that: During the blending process of the polymer masterbatch and polycarbonate resin, 0.3% to 0.8% by mass of UV stabilizer and 0.2% to 0.5% by mass of heat stabilizer are also added to improve the weather resistance and color stability of the resulting mask in long-term outdoor use.

10. The method for preparing the LED display screen mask as described in claim 9, characterized in that: The UV stabilizer is a hindered amine light stabilizer, and the heat stabilizer is an organophosphate compound. Both are uniformly dispersed in the polycarbonate matrix during the co-extrusion melt stage. After the mask is continuously aged for 1000 hours at 85°C and 85% relative humidity, the color difference is less than 1.5, and there is no obvious yellowing or deterioration of mechanical properties.

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