A method and system for seamless holographic pattern imprinting on curved substrates

Abstract

This invention relates to a method and system for seamless holographic pattern imprinting on curved substrates, specifically in the field of holographic pattern imprinting on curved surfaces. The method includes: scanning the curved substrate to obtain a curvature curve of the imprinting surface; dividing the curvature curve of the imprinting surface into a curvature range according to a preset allowable curvature fluctuation range; dividing the curved surface into segmented pressure regions and segmented average curvatures based on the curvature range; searching for the corresponding imprinting pressure in a preset curvature pressure database based on the segmented average curvature; controlling corresponding pneumatic adsorption devices to respectively adhere to the areas of the flexible printing plate corresponding to the segmented pressure regions; then controlling a robotic arm to move the flexible printing plate and adhere it to the curved substrate; and applying the corresponding imprinting pressure to the areas of the flexible printing plate corresponding to the segmented pressure regions after the adhesion process. This invention achieves seamless holographic pattern imprinting on curved substrates.

Description

Technical Field

[0001] This invention relates to the field of holographic pattern embossing on curved surfaces, and in particular to a seamless holographic pattern embossing method and system suitable for curved substrates. Background Technology

[0002] Holographic patterns are special patterns created based on the principles of light diffraction and interference. By constructing micron-level microstructures on the surface of a substrate, they achieve a three-dimensional visual effect, dynamic light and shadow changes, or rainbow diffraction luster. These patterns can present a "floating" and "angle-dependent" visual effect without the need for additional light sources. Furthermore, the fabrication process of the microstructures is complex and difficult to precisely replicate, thus combining high-end decorative value with strong anti-counterfeiting properties. They are widely used in the surface treatment of high-end products such as cosmetic bottles, wine bottles, and electronic product casings.

[0003] In the field of planar substrates, holographic pattern molding technology has matured. Through processes such as rigid roller embossing and hot stamping, batch and high-precision pattern transfer can be achieved. For example, rigid roller embossing uses a rigid metal roller with microstructures or patterns engraved on its surface, which rotates and squeezes in conjunction with an elastic pressure roller to transfer the pattern (such as holographic microstructures or printed patterns) from the roller to the surface of planar or near-planar substrates such as paper and plastic film. The process is then completed through ink transfer, drying, or curing.

[0004] Regarding the aforementioned technologies, when applied to curved substrates, there are technical shortcomings: the rigid roller has a rigid structure, and when it comes into contact with the curved substrate, it can only form local line contact, resulting in poor adhesion and uneven pressure distribution. This not only causes local blurring, missing parts or uneven brightness of the holographic pattern, but also makes it impossible to achieve seamless continuity of the pattern, which cannot meet the needs of high-end products, and there is still room for improvement. Summary of the Invention

[0005] To address the issues of defects and lack of seamless continuity in holographic patterns when imprinting on curved substrates, this invention provides a method and system for seamless holographic pattern imprinting suitable for curved substrates.

[0006] In a first aspect, the present invention provides a seamless holographic pattern imprinting method suitable for curved substrates, employing the following technical solution: A method for seamless holographic pattern imprinting suitable for curved substrates includes: Step 1: Perform surface scanning on the curved substrate to be imprinted to obtain the surface curvature curve of the imprinting surface. The surface curvature curve is a mapping curve between the surface position and the curvature. Step 2: Divide the curvature range according to the preset allowable curvature fluctuation range based on the curvature curve of the imprinted surface; Step 3: Divide the surface position according to the curvature range to obtain the segmented pressure region and the segmented average curvature; Step 4: Find the corresponding imprinting pressure in the preset curvature pressure database based on the segmented average curvature; Step 5: Control the corresponding pneumatic adsorption device to pick up the flexible printing plate area corresponding to the segmented pressure area, then control the robotic arm to move the flexible printing plate and the curved substrate to bond, and apply the corresponding printing pressure to the flexible printing plate area corresponding to the segmented pressure area after the bonding process.

[0007] By adopting the above technical solution, the curvature curve of the curved substrate is first obtained by scanning the imprinting surface. Then, the curvature range and corresponding segmented pressure areas are divided. The average curvature of each segment is determined according to the range. Based on the curvature, the corresponding imprinting pressure is matched in the preset curvature pressure database. Finally, the flexible printing plate is adsorbed in sections by a pneumatic adsorption device. The flexible printing plate is then bonded to the substrate by a robotic arm and the corresponding imprinting pressure is applied in sections. This method solves the problems of insufficient adhesion and uneven pressure when imprinting on curved substrates, achieving seamless and continuous patterns and stable and uniform visual effects, meeting the needs of high-end products.

[0008] Optionally, methods prior to surface scanning of the curved substrate to be imprinted include: Step 10: Clean the embossed surface of the curved substrate; Step 11: Control the plasma jet array to perform low-temperature activation treatment on the imprint surface.

[0009] By adopting the above technical solution, the method of cleaning the surface of the curved substrate and then performing low-temperature plasma activation treatment solves the problems of low accuracy in curvature recognition and incomplete holographic pattern imprinting caused by impurities, oil stains and insufficient surface adhesion on the embossing surface of the curved substrate, thus achieving the effect of improving the surface adhesion of the curved substrate.

[0010] Optionally, methods for controlling the movement of the robotic arm to bond the flexible printing plate and the curved substrate include: Step 50: Obtain the real-time gap between the flexible printing plate and the curved substrate; Step 51: When the real-time gap falls within the preset gap range, control the robotic arm to apply the corresponding imprinting pressure to the area of ​​the flexible printing plate corresponding to the segmented pressure area. Step 52: When the real-time gap does not fall within the preset gap range, the real-time gap that does not fall within the preset gap range is defined as an abnormal gap, and the segmented pressure area corresponding to the abnormal gap is defined as an abnormal segmented area. Step 53: Obtain the area of ​​the flexible printing plate that needs to be laminated corresponding to the abnormal segmentation area; Step 54: Locate the corresponding pneumatic adsorption device number based on the area to be bonded; Step 55: Control the robotic arm to push the area to be bonded corresponding to the number of the pneumatic adsorption device, and obtain the reaction force of the robotic arm in the area to be bonded; Step 56: When the reaction force exceeds the preset safety pressure, output a preset alarm signal; Step 57: When the reaction force is less than the safety pressure, continue to push the area to be bonded corresponding to the number of the pneumatic adsorption device until the real-time gap falls within the gap range or the reaction force is greater than the safety pressure.

[0011] By adopting the above technical solution, the real-time gap between the flexible printing plate and the curved substrate is obtained and compared with the preset gap range. When the gap is normal, the corresponding imprinting pressure is applied directly to the corresponding sections. When the gap is abnormal, the abnormal segment area and the corresponding flexible printing plate area to be bonded are identified. Based on the number of the pneumatic adsorption device corresponding to the area to be bonded, a robotic arm pushes the area and monitors the reaction force. Based on the relationship between the reaction force and the preset safety pressure, pushing, alarm, or continuous adjustment operations are performed. This solves the problem of improper pressure application, holographic pattern distortion, or damage to the flexible printing plate caused by abnormal gaps during the bonding process between the curved substrate and the flexible printing plate, achieving the effect of real-time monitoring and adjustment of the bonding gap.

[0012] Optionally, a solution is also included for when the reaction force exceeds a preset safety pressure, the method comprising: Step 560: Perform curvature change analysis based on the surface curvature curve to obtain the abnormal curvature change pattern corresponding to the abnormal segmented region; Step 561: When the abnormal curvature change pattern is a preset concave pattern, the abnormal segmented region corresponding to the curvature change pattern is defined as a concave region. Step 562: Locate the mating areas on both sides based on the mating area corresponding to the concave area; Step 563: Locate the corresponding pneumatic adsorption device numbers on both sides based on the bonding areas on both sides; Step 564: Control the pneumatic adsorption device corresponding to the number of the pneumatic adsorption device to relax the suction between the pneumatic adsorption device and the area to be bonded, and then control the robotic arm to push the bonding areas on both sides corresponding to the numbers of the pneumatic adsorption devices on both sides in a preset inward moving direction, wherein the inward moving direction is the direction of the bonding areas on both sides toward the area to be bonded. Step 565: Obtain the real-time pressure feedback after relaxation on the pneumatic adsorption device corresponding to the pneumatic adsorption device number. Step 566: When the real-time pressure is less than the safe pressure, continue to push the area to be bonded corresponding to the number of the pneumatic adsorption device; Step 567: When the real-time pressure is at a safe pressure, stop pushing the area to be bonded corresponding to the number of the pneumatic adsorption device; Step 568: When the real-time gap does not fall within the gap range, repeat steps 55 to 565 until the real-time gap falls within the gap range.

[0013] By adopting the above technical solution, when the reaction force exceeds the preset safety pressure, the abnormal curvature change law of the abnormal segment area is first analyzed according to the curvature curve of the curved surface. After determining that it is a concave area, the bonding areas on both sides and the corresponding pneumatic adsorption device numbers are found. Then, the adsorption force of the pneumatic adsorption device in the bonding area is relaxed, and the pneumatic adsorption devices in the bonding areas on both sides are pushed to move towards the bonding area. At the same time, the feedback pressure of the pneumatic adsorption device is monitored in real time, and the pushing action is adjusted according to the relationship between the pressure and the safety pressure. If the standard is not met, the adjustment is repeated. This method solves the problem that when the reaction force exceeds the standard during the bonding process, it is impossible to adjust the abnormal gap for the concave area, resulting in the bonding of the concave area not meeting the standard. It achieves the goal of ensuring that the bonding of the concave area falls within the preset gap range while avoiding damage to the flexible printing plate.

[0014] Optionally, the method for controlling the robotic arm to push the two sides of the pneumatic adsorption device corresponding to the two side contact areas in a preset inward moving direction includes: Step 5640: Obtain the device distance between the pneumatic adsorption device corresponding to the pneumatic adsorption device number and the pneumatic adsorption devices corresponding to the pneumatic adsorption device numbers on both sides. Step 5641: When the device distance is 0, control the pneumatic adsorption devices corresponding to the numbers on both sides to relax the suction between the two sides of the contact area, and then move them in the outward moving direction within the contact area on both sides. The outward moving direction is the direction in which the contact area on both sides moves away from the area to be contacted. Control the pneumatic adsorption devices corresponding to the numbers on both sides to hold the contact area on both sides. Repeat steps 564 to 568 until the gap falls into the gap range in real time.

[0015] By adopting the above technical solution, the distance of the collection device is collected. When the device distance is 0 and there is no room for movement, the pneumatic adsorption devices on both sides are controlled to relax the suction force on the two sides of the bonding area, and then move away from the area to be bonded and re-adsorb. The aforementioned steps are repeated to adjust the process. This solves the problem that when the device distance is 0, it is impossible to push the two sides of the bonding area to move inward, resulting in the abnormal gap that cannot be eliminated.

[0016] Optionally, it also includes a verification method for determining whether to control the robotic arm to push the contact areas corresponding to the pneumatic adsorption devices on both sides in a preset inward moving direction when the reaction force is greater than the preset safety pressure. This method includes: Step 5642: Obtain the back image of the flexographic printing plate; Step 5643: Based on the back image of the flexible printing plate, find the preset imprinting border on the imprinting surface corresponding to the curved substrate; Step 5644: When the imprinted border is not present, control the robotic arm to push the two sides of the bonding area corresponding to the numbers of the pneumatic adsorption devices on both sides in the inward moving direction; Step 5645: When the imprinting border exists, perform a horizontal line scan on the imprinting surface to obtain the horizontal length of the imprinting surface on each horizontal line; Step 5646: Match the horizontal length with the preset horizontal length of the printing plate based on the same horizontal line; Step 5647: When the horizontal length does not match the horizontal length of the printing plate, re-acquire the curved substrate to be imprinted.

[0017] By adopting the above technical solution, when the reaction force is greater than the preset safety pressure, the preset imprinting border of the imprinting surface is found based on the image of the back of the flexible printing plate to verify the compatibility. When there is no imprinting border, the two sides of the bonding area are pushed normally. When there is an imprinting border, the length of each horizontal line on the imprinting surface is obtained by scanning the horizontal line and compared with the preset horizontal length of the printing plate. If they do not match, a qualified curved substrate is obtained again. This solves the problem that blindly pushing may cause imprinting failure when the reaction force exceeds the standard due to the mismatch between the curved substrate and the flexible printing plate.

[0018] Optional, also includes: Step 12: Analyze the curvature changes based on the surface curvature curve to obtain the curvature change patterns corresponding to the segmented pressure regions; Step 13: When the curvature change pattern is a preset convex surface pattern, the segmented pressure region corresponding to the curvature change pattern is defined as a convex surface region; Step 14: Filter out the average curvature of the convex region based on the segmented average curvature and the convex region; Step 15: Select the convex area with the largest average curvature based on the average curvature of the convex surface, and define the area of ​​the flexible printing plate corresponding to the convex surface area as the priority imprinting area. Step 16: Determine other imprinting areas based on the preferred imprinting area; Step 17: Determine the imprinting order based on the priority imprinting area and other imprinting areas. The imprinting order is to first imprint the priority imprinting area, and then imprint the other imprinting areas on both sides of the priority imprinting area one by one. Step 18: Control the robotic arm to imprint according to the imprinting sequence.

[0019] By adopting the above technical solution, the convex areas that conform to the convex surface law in the curvature change law and the corresponding average curvature of the convex surface are screened, and the area with the largest average curvature of the convex surface is determined as the priority imprinting area. Other imprinting areas are determined, and the robotic arm is controlled to imprint in the imprinting order of the priority area first, and then imprinting to both sides one by one. This solves the problem of unreasonable imprinting order caused by curvature difference when imprinting on curved substrates, resulting in unsatisfactory imprinting pattern quality.

[0020] Optionally, specific methods for controlling the robotic arm to perform imprinting according to the imprinting sequence include: Step 180: After the robotic arm applies the corresponding imprinting pressure to the priority imprinting area, it finds the corresponding current pneumatic adsorption device number based on the priority imprinting area and controls the pneumatic adsorption device corresponding to the current pneumatic adsorption device number to relax the suction. Step 181: Locate the imprinting areas on both sides based on the priority imprinting area; Step 182: Locate the boundary line between the priority imprinting area and the imprinting areas on both sides; Step 183: Control the pneumatic adsorption device corresponding to the current pneumatic adsorption device number to move to the boundary line of the area within the priority imprinting area, and then control the pneumatic adsorption device corresponding to the current pneumatic adsorption device number to adhere to the priority imprinting area. Step 184: Determine the imprinting direction on both sides based on the preferred imprinting area and the imprinting areas on both sides. The imprinting direction on both sides is the moving imprinting direction within the imprinting areas on both sides from the side closer to the preferred imprinting area to the side farther away from the preferred imprinting area. Step 185: Control the robotic arms corresponding to the two imprinting areas respectively to apply the corresponding imprinting pressure to the two imprinting areas according to their respective imprinting directions.

[0021] By adopting the above technical solution, after imprinting in the priority imprinting area, the corresponding pneumatic adsorption device is controlled to relax the suction force, the boundary line between the priority imprinting area and the imprinting areas on both sides is found, the adsorption device is moved to the boundary line and re-adsorbed and fixed, and the robotic arm is controlled to apply imprinting pressure to the areas on both sides in the direction extending from the priority area to both sides, thus achieving the effect of seamless imprinting between the priority imprinting area and the areas on both sides.

[0022] Optional, also includes: Step 58: When the pneumatic adsorption device is controlled to hold the flexible printing plate, the pneumatic adsorption device is used to adsorb according to the preset strong suction force. Step 59: When the robotic arm moves the flexible printing plate and initially adheres it to the curved substrate, the pneumatic adsorption device is used in conjunction with the robotic arm to adhere the plate according to the preset weak suction level.

[0023] By adopting the above technical solution and using the method of controlling the suction force of the pneumatic adsorption device in stages, the coordinated adaptation of adsorption fixation and bonding adjustment is achieved, which not only ensures the stability of the printing plate transfer process, but also provides support for subsequent precise bonding.

[0024] Secondly, the present invention provides a seamless holographic pattern imprinting system suitable for curved substrates, employing the following technical solution: A seamless holographic pattern embossing system suitable for curved substrates includes: The acquisition module is used to acquire real-time gap, reaction force, real-time pressure, device distance, and back view image; A memory for storing a program for a seamless holographic pattern imprinting method applicable to curved substrates, as described above; The processor loads and executes programs from memory.

[0025] By adopting the above technical solution, the curvature curve of the curved substrate is first obtained by scanning the imprinting surface. Then, the curvature range and corresponding segmented pressure areas are divided. The average curvature of each segment is determined according to the range. Based on the curvature, the corresponding imprinting pressure is matched in the preset curvature pressure database. Finally, the flexible printing plate is adsorbed in sections by a pneumatic adsorption device. The flexible printing plate is then bonded to the substrate by a robotic arm and the corresponding imprinting pressure is applied in sections. This method solves the problems of insufficient adhesion and uneven pressure when imprinting on curved substrates, achieving seamless and continuous patterns and stable and uniform visual effects, meeting the needs of high-end products.

[0026] In summary, the present invention has at least one of the following beneficial technical effects: It solves the problems of insufficient adhesion and uneven pressure when imprinting on curved substrates, achieving seamless and continuous patterns and stable and uniform visual effects, meeting the needs of high-end products. This invention solves the problem that when the reaction force exceeds the standard during the bonding process, it is impossible to adjust the abnormal gap for the concave area, resulting in substandard bonding of the concave area. It achieves the goal of ensuring that the bonding of the concave area falls within the preset gap range while avoiding damage to the flexible printing plate. Attached Figure Description

[0027] Figure 1 This is a flowchart of a seamless holographic pattern imprinting method applicable to curved substrates, as described in an embodiment of this application. Detailed Implementation

[0028] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0029] This invention discloses a method for seamless holographic pattern imprinting suitable for curved substrates. (Refer to...) Figure 1 A method for seamless holographic pattern imprinting suitable for curved substrates includes: Step 1: Perform surface scanning on the curved substrate to be imprinted to obtain the surface curvature curve of the imprinting surface. The surface curvature curve is a mapping curve between the surface position and the curvature.

[0030] Curved substrates refer to substrates with varying curvature on their surfaces. Common examples include cylindrical, spherical, ellipsoidal, or irregularly shaped objects, such as cosmetic bottles, wine bottles, and electronic product casings. These curved substrates are pre-defined by those skilled in the art.

[0031] The embossed surface refers to the surface of a curved substrate that needs to be embossed with a holographic pattern. This embossed surface is obtained from the holographic pattern to be embossed on the curved substrate.

[0032] A surface curvature curve refers to a curve showing the curvature variation at different locations on the embossed surface. The surface curvature curve is generated by projecting a laser line onto the curved substrate using a laser emitter. A matching CCD camera captures the reflected laser spot on the curved surface. Using geometric trigonometric relationships, the three-dimensional coordinates of each point on the substrate surface are calculated based on the offset of the laser spot. This process is then continuously scanned to cover the entire curved surface, fitting the discrete coordinate points into a surface model. Finally, a numerical differential algorithm is used to calculate the curvature at each point, ultimately generating the surface curvature curve.

[0033] Step 2: Divide the curvature range according to the preset allowable curvature fluctuation range based on the curvature curve of the imprinted surface.

[0034] The allowable curvature fluctuation range refers to the numerical range within which the curvature is allowed to vary. This range is set by those skilled in the art based on actual imprinting requirements and the characteristics of the curved substrate.

[0035] A curvature range refers to several relatively uniform curvature variation intervals obtained by dividing the curvature curve of a surface according to the allowable range of curvature fluctuation. This curvature range is formed by traversing all data points on the surface curvature curve, grouping adjacent points whose curvature values ​​fall within the same allowable range of fluctuation into the same curvature range, and recording the start and end positions of each range as well as the corresponding curvature value interval, ultimately forming multiple curvature ranges.

[0036] Step 3: Divide the surface position according to the curvature range to obtain the segmented pressure region and the segmented average curvature.

[0037] The segmented pressure zone refers to the area where different imprint pressures are applied subsequently. This zone is obtained by dividing the curved surface of the imprint surface according to the range of curvature.

[0038] Piecewise average curvature refers to the average curvature of each segmented pressure region. It is obtained by summing the curvature values ​​within each segmented pressure region and then dividing by the number of data points within that region.

[0039] Step 4: Find the corresponding imprinting pressure in the preset curvature pressure database based on the segmented average curvature.

[0040] The curvature pressure database contains a mapping relationship between piecewise average curvature and imprinting pressure. This database was pre-established by researchers in the field through experiments. In these experiments, different pressures were applied to curved substrates with different curvature ranges to conduct imprinting tests, and the pressure values ​​that achieved the best imprinting effect were recorded, thus forming the curvature pressure database.

[0041] Imprint pressure refers to the pressure value used to imprint segmented pressure areas on the imprinting surface. This imprint pressure is obtained by looking up the corresponding imprint pressure in a curvature pressure database based on the average curvature of the segments.

[0042] Step 5: Control the corresponding pneumatic adsorption device to pick up the flexible printing plate area corresponding to the segmented pressure area, then control the robotic arm to move the flexible printing plate and the curved substrate to bond, and apply the corresponding printing pressure to the flexible printing plate area corresponding to the segmented pressure area after the bonding process.

[0043] A flexible printing plate is a type of printing plate that can adapt to changes in the curvature of a curved substrate surface, enabling seamless imprinting of holographic patterns. This flexible printing plate is pre-fabricated by those skilled in the art based on the imprinting surface of the curved substrate.

[0044] The pneumatic adsorption device generates suction to firmly adsorb the flexible printing plate. The robotic arm moves the flexible printing plate according to a preset trajectory and speed, so that it accurately fits the curved substrate. Then, the corresponding printing pressure is applied to the flexible printing plate area corresponding to the segmented pressure area.

[0045] The method prior to surface scanning of the curved substrate to be imprinted includes: Step 10: Clean the embossed surface of the curved substrate.

[0046] Cleaning refers to the physical removal of dust and oil stains from the imprinting surface in sequence. This cleaning method is pre-defined by those skilled in the art.

[0047] Step 11: Control the plasma jet array to perform low-temperature activation treatment on the imprint surface.

[0048] A plasma jet array refers to an array structure composed of multiple plasma jet devices arranged in a specific manner. This array is pre-configured by those skilled in the art.

[0049] Low-temperature activation treatment refers to the treatment of the imprint surface using low-temperature plasma generated by a plasma jet array. This alters the surface properties of the imprint surface, enhancing its adhesion to the flexographic printing plate. This treatment method effectively activates the imprint surface by controlling parameters of the plasma jet array, such as treatment time, gas type, and power.

[0050] The methods for controlling the movement of the robotic arm to bond the flexible printing plate and the curved substrate include: Step 50: Obtain the real-time gap between the flexible printing plate and the curved substrate.

[0051] Real-time gap refers to the real-time distance between the flexographic printing plate and the printing surface of the curved substrate during the bonding process. This real-time gap is obtained in real time by placing high-precision distance sensors at corresponding positions on the flexographic printing plate and the curved substrate.

[0052] Step 51: When the real-time gap falls within the preset gap range, control the robotic arm to apply the corresponding imprinting pressure to the area of ​​the flexible printing plate corresponding to the segmented pressure area.

[0053] The gap range refers to the allowable distance between the flexible printing plate and the curved substrate when they are bonded. This gap range is set by those skilled in the art based on actual imprinting requirements and the characteristics of the curved substrate. The gap must ensure sufficient contact between the flexible printing plate and the curved substrate during imprinting, while also preventing excessive imprinting pressure due to an excessively small gap, which could distort the holographic pattern. When the real-time gap falls within the preset gap range, it indicates that the bonding degree between the flexible printing plate and the curved substrate has met the imprinting requirements. At this point, the robotic arm applies the corresponding imprinting pressure to the areas of the flexible printing plate corresponding to the segmented pressure areas.

[0054] Step 52: When the real-time gap does not fall within the preset gap range, the real-time gap that does not fall within the preset gap range is defined as an abnormal gap, and the segmented pressure area corresponding to the abnormal gap is defined as an abnormal segmented area.

[0055] Abnormal gaps are obtained by comparing real-time gaps with gap ranges in real time. Real-time gaps that do not fall within the gap range are considered abnormal gaps.

[0056] The segmented pressure area is obtained by using a laser emitter to locate and identify the specific area on the imprint surface corresponding to the abnormal gap.

[0057] Step 53: Obtain the area of ​​the flexible printing plate that needs to be bonded to the abnormal segmentation area.

[0058] The area to be bonded refers to the region on the flexible printing plate used to adjust the real-time gap. The area to be bonded is obtained by using a laser emitter to locate and identify the region on the flexible printing plate corresponding to the abnormal segmented area imprinted on the imprinting surface.

[0059] Step 54: Locate the corresponding pneumatic adsorption device number based on the area to be bonded.

[0060] The pneumatic adsorption device number refers to the number of the pneumatic adsorption device that adheres to the area to be bonded on the flexographic printing plate. This number is obtained by those skilled in the art who pre-number the pneumatic adsorption devices used in each area of ​​the flexographic printing plate. Each area on the flexographic printing plate has a one-to-one mapping relationship with a pneumatic adsorption device number, with each area corresponding to a specific pneumatic adsorption device number. Then, a laser emitter is used to locate and identify the specific area of ​​the flexographic printing plate, thereby determining the number of the pneumatic adsorption device.

[0061] Step 55: Control the robotic arm to push the area to be bonded corresponding to the number of the pneumatic adsorption device, and obtain the reaction force of the robotic arm in the area to be bonded.

[0062] The reaction force refers to the reaction force felt by the flexible printing plate tension when the robotic arm pushes the area to be bonded close to the abnormal segmentation area. This reaction force is obtained by monitoring the reaction force sensor.

[0063] Step 56: When the reaction force is greater than the preset safety pressure, output the preset alarm signal.

[0064] The safety pressure refers to the pressure threshold that prevents damage to the flexographic printing plate due to excessive thrust from the robotic arm. The safety pressure is determined in advance by professionals in the field through multiple impression tests based on the material characteristics and thickness parameters of the flexographic printing plate, as well as the required precision of the holographic pattern.

[0065] An alarm signal indicates that the robotic arm is about to damage the flexographic printing plate when pushing the area to be bonded close to an abnormal segment. This signal is pre-set by those skilled in the art and is presented in the form of sound and light, such as a flashing warning light. When the reaction force exceeds the preset safety pressure, it means that the robotic arm is pushing the area to be bonded too forcefully, which may damage the flexographic printing plate. However, if there are still some areas on the abnormal segment that do not fall within the real-time gap between the flexographic printing plate and the abnormal segment, an alarm signal is output to prompt the robotic arm to stop pushing and wait for subsequent adjustments.

[0066] Step 57: When the reaction force is less than the safety pressure, continue to push the area to be bonded corresponding to the number of the pneumatic adsorption device until the real-time gap falls within the gap range or the reaction force is greater than the safety pressure.

[0067] When the reaction force is less than the safety pressure, it means that the area to be fitted can still be pushed closer to the abnormal segment area until the real-time gap between the area to be fitted and the abnormal segment area falls within the gap range, or the reaction force is greater than the safety pressure and cannot be pushed closer, and subsequent adjustment work is required.

[0068] This also includes a solution for when the reaction force exceeds the preset safety pressure, which includes: Step 560: Perform curvature change analysis based on the surface curvature curve to obtain the abnormal curvature change pattern corresponding to the abnormal segmented region.

[0069] The abnormal curvature variation pattern refers to the rising and falling variation pattern of the surface curvature curve in an abnormal segment region. The method for analyzing abnormal curvature variations involves first extracting a subset of curvature data corresponding to the abnormal segment region from the surface curvature curve; then quantifying the rising and falling relationship between adjacent curvature values ​​using first-order difference calculations; combining this with low-order polynomial fitting to obtain a smooth curvature trend curve to eliminate sampling errors; and finally, combining the local difference results with the overall fitting trend to determine whether the curvature in this region exhibits a continuous rising, continuous falling, fluctuating, or stable variation pattern. The variation pattern obtained from the above process is the abnormal curvature variation pattern.

[0070] Step 561: When the abnormal curvature change pattern is a preset concave pattern, the abnormal segmented region corresponding to the curvature change pattern is defined as a concave region.

[0071] The concave surface pattern is characterized by a curvature that first decreases and then increases, exhibiting a concave shape. The corresponding surface region also exhibits a concave shape. This pattern was pre-defined by those skilled in the art.

[0072] When the abnormal curvature change pattern is a preset concave pattern, it means that the abnormal curvature change pattern presents a concave shape, and the corresponding abnormal segment region is also a concave region. Therefore, the abnormal segment region corresponding to the curvature change pattern is defined as a concave region.

[0073] Step 562: Locate the mating areas on both sides based on the mating area corresponding to the concave area.

[0074] The two-sided bonding area refers to the areas on both sides of the area to be bonded on the flexographic printing plate. This area is obtained by using a laser emitter to locate and identify the area to be bonded on the flexographic printing plate corresponding to the concave area, and then finding the areas on both sides of the area to be bonded.

[0075] Step 563: Locate the corresponding pneumatic adsorption device numbers on both sides based on the contact areas on both sides.

[0076] The numbers of the pneumatic adsorption devices on both sides refer to the numbers of the pneumatic adsorption devices that adhere to the bonding areas on both sides of the flexible printing plate. The method for obtaining these numbers is the same as for the pneumatic adsorption device numbers in step 54; a laser emitter is used to locate and identify the bonding areas on both sides of the flexible printing plate, thereby determining the numbers of the pneumatic adsorption devices on both sides. Step 564: Control the pneumatic adsorption device corresponding to the number of the pneumatic adsorption device to relax the suction between the pneumatic adsorption device and the area to be bonded, and then control the robotic arm to push the bonding areas on both sides corresponding to the numbers of the pneumatic adsorption devices on both sides in a preset inward moving direction, which is the direction in which the bonding areas on both sides are facing the area to be bonded.

[0077] The device corresponding to the pneumatic adsorption device number in the area to be bonded is controlled to release its suction force. Then, the robotic arm pushes the bonding areas corresponding to the pneumatic adsorption device numbers on both sides toward the area to be bonded. At the same time, the robotic arm is controlled to push the bonding area corresponding to the pneumatic adsorption device number, thereby bringing the area to be bonded closer to the abnormal segmented area.

[0078] Step 565: Obtain the real-time pressure feedback from the pneumatic adsorption device after relaxation, corresponding to the number of the pneumatic adsorption device.

[0079] Real-time pressure refers to the pressure value reported by the internal pressure sensor of the pneumatic adsorption device after the suction force is released. This real-time pressure is obtained through real-time monitoring by the pressure sensor.

[0080] Step 566: When the real-time pressure is less than the safe pressure, continue to push the area to be bonded corresponding to the number of the pneumatic adsorption device.

[0081] When the real-time pressure is less than the safe pressure, it means that the thrust of the robotic arm pushing the area to be bonded corresponding to the number of the pneumatic adsorption device is within the safe range, and it can continue to push to reduce the real-time gap.

[0082] Step 567: When the real-time pressure is at a safe pressure, stop pushing the area to be bonded corresponding to the number of the pneumatic adsorption device.

[0083] When the real-time pressure is at a safe level, it indicates that continued pushing will damage the flexible printing plate. At this point, the robotic arm should be stopped from pushing the area to be bonded corresponding to the number of the pneumatic adsorption device.

[0084] Step 568: When the real-time gap does not fall within the gap range, repeat steps 55 to 565 until the real-time gap falls within the gap range.

[0085] When the real-time gap does not fall within the gap range, it indicates that the current fitting adjustment has not yet met the requirements, and the operation process of steps 55 to 565 needs to be repeated: continuously push the area to be fitted by the robotic arm, while monitoring the changes in reaction force and real-time pressure, until the real-time gap falls within the preset gap range or the real-time pressure reaches the safe pressure threshold.

[0086] The method for controlling the robotic arm to push the two sides of the pneumatic adsorption device corresponding to the two sides of the contact area in a preset inward moving direction includes: Step 5640: Obtain the device distance between the pneumatic adsorption device number corresponding to the pneumatic adsorption device and the pneumatic adsorption devices numbered on both sides.

[0087] The device distance refers to the straight-line distance on the flexible printing plate mounting plane between the pneumatic adsorption device corresponding to its number and the pneumatic adsorption devices corresponding to their numbers on both sides. This device distance is obtained by installing high-precision displacement sensors on the pneumatic adsorption devices.

[0088] Step 5641: When the device distance is 0, control the pneumatic adsorption devices corresponding to the numbers on both sides to relax the suction between the two sides and the bonding area. Then, move in the bonding area on both sides in the outward direction, which is the direction of the bonding area on both sides away from the area to be bonded. Control the pneumatic adsorption devices corresponding to the numbers on both sides to hold the bonding area on both sides. Repeat steps 564 to 568 until the gap falls into the gap range in real time.

[0089] When the device distance is 0, it indicates that the control robotic arm has reached the point where there is no more room for movement after pushing the two sides of the pneumatic adsorption devices (corresponding to their numbers) in the inward direction. At this time, the control robotic arm first releases the suction force of the two pneumatic adsorption devices on the two sides of the contact area, and then moves the two pneumatic adsorption devices in the outward direction within the contact area. After they are in place, the control robotic arm re-engages the pneumatic adsorption devices to hold the two sides of the contact area, and then resumes the inward pushing operation while simultaneously monitoring the real-time pressure and real-time gap changes until the real-time gap falls within the preset gap range or the real-time pressure reaches the safety threshold.

[0090] This includes a verification method for determining whether to control the robotic arm to push the two sides of the pneumatic adsorption device corresponding to their respective numbers in a preset inward moving direction when the reaction force exceeds the preset safety pressure. This method includes: Step 5642: Obtain the back image of the flexographic printing plate.

[0091] A back-side image refers to an image taken from the back of a flexographic printing plate when it is being pressed against a curved substrate. This back-side image is obtained in real time by mounting a camera on the back of the flexographic printing plate.

[0092] Step 5643: Based on the back image of the flexible printing plate, find the preset imprinting border on the imprinting surface corresponding to the curved substrate.

[0093] An impression border is a reference mark border visible around the impression surface, used to detect whether the flexographic printing plate completely covers the impression surface. This border is pre-set by those skilled in the art and located from an image of the back of the flexographic printing plate.

[0094] Step 5644: When the imprinted border is not present, control the robotic arm to push the two sides of the bonding area corresponding to the numbers of the pneumatic adsorption devices on both sides in the inward moving direction.

[0095] When the imprinting border is absent, it means that the flexible printing plate completely covers the border of the imprinting surface. It can also control the robotic arm to push the two sides of the bonding area corresponding to the pneumatic adsorption device numbers on both sides in the inward moving direction.

[0096] Step 5645: When the imprinting border exists, perform a horizontal line scan on the imprinting surface to obtain the horizontal length of the imprinting surface on each horizontal line.

[0097] The horizontal length refers to the actual length of the imprinted surface on each horizontal line. This horizontal length is obtained by scanning the imprinted surface line by line along the horizontal direction with a laser scanner, recording the coordinates of the intersection points of each scan line and the edge of the imprinted surface, and calculating the distance between adjacent intersection points.

[0098] When an imprint border exists, it means that the flexographic printing plate cannot completely cover the border of the imprint surface. It is necessary to check whether the length of the imprint surface on the same horizontal line is longer than the length of the flexographic printing plate. At this time, the horizontal length of the imprint surface on each horizontal line is scanned.

[0099] Step 5646: Match the horizontal length with the preset horizontal length of the printing plate based on the same horizontal line.

[0100] The horizontal length of the printing plate refers to the actual length of the flexographic printing plate on each horizontal line. The matching method involves comparing the horizontal length of the printing surface on each horizontal line with the corresponding preset horizontal length of the flexographic printing plate, calculating the difference to determine if it exceeds the allowable error range. If the difference is within the allowable range, the horizontal line is considered successfully matched; if the difference exceeds the range, the horizontal line is considered to have a length mismatch problem.

[0101] Step 5647: When the horizontal length does not match the horizontal length of the printing plate, re-acquire the curved substrate to be imprinted.

[0102] When the horizontal length does not match the horizontal length of the printing plate, it indicates that the curved substrate to be printed is not a qualified part, and a new curved substrate should be obtained.

[0103] This also includes: Step 12: Analyze the curvature changes based on the surface curvature curve to obtain the curvature change patterns corresponding to the segmented pressure regions.

[0104] The curvature variation law refers to the rising and falling variation law of the curvature curve of the segmented pressure region. The curvature variation analysis method is as follows: first, extract the curvature data subset corresponding to the segmented pressure region from the surface curvature curve; then, quantify the rising and falling relationship of adjacent curvature values ​​through first-order difference calculation; combine with low-order polynomial fitting to obtain a smooth curvature trend curve to eliminate sampling errors; finally, combine the local difference results with the overall fitting trend to determine whether the curvature of the region shows a continuous rising, continuous falling, fluctuating change, or stable change law. The variation law obtained in the above process is the curvature variation law.

[0105] Step 13: When the curvature change pattern is a preset convex surface pattern, the segmented pressure region corresponding to the curvature change pattern is defined as a convex surface region.

[0106] The convex surface pattern is characterized by a curvature that first increases and then decreases, exhibiting an upward convex shape. The corresponding curved surface region also exhibits an upward convex shape. This pattern is obtained through pre-defined settings by those skilled in the art.

[0107] When the curvature change pattern is a preset convex pattern, it means that the curvature change pattern presents an upward convex shape, and the corresponding segmented pressure area is also a convex area. Therefore, the segmented pressure area corresponding to the curvature change pattern is defined as a convex area.

[0108] Step 14: Filter out the average curvature of the convex region based on the segmented average curvature and the convex region.

[0109] The average curvature of a convex surface refers to the piecewise average curvature of the convex surface region. The average curvature of a convex surface is obtained by selecting the piecewise average curvature of the convex surface region from the piecewise average curvatures corresponding to all segmented pressure regions.

[0110] Step 15: Select the convex area with the largest average curvature based on the average curvature of the convex surface, and define the area of ​​the flexible printing plate corresponding to the convex surface area as the priority printing area.

[0111] Step 16: Determine other imprinting areas based on the priority imprinting area.

[0112] Other printing areas refer to the areas remaining in the flexographic printing plate after excluding the priority printing areas. These other printing areas are identified by locating and recognizing the remaining areas after excluding the priority printing areas.

[0113] Step 17: Determine the imprinting order based on the priority imprinting area and other imprinting areas. The imprinting order is to first imprint the priority imprinting area, and then imprint the other imprinting areas on both sides of the priority imprinting area one by one.

[0114] Step 18: Control the robotic arm to imprint according to the imprinting sequence.

[0115] The specific methods for controlling the robotic arm to perform the imprinting according to the imprinting sequence include: Step 180: After the robotic arm applies the corresponding imprinting pressure to the priority imprinting area, it finds the corresponding current pneumatic adsorption device number based on the priority imprinting area and controls the pneumatic adsorption device corresponding to the current pneumatic adsorption device number to relax the suction.

[0116] Step 181: Locate the imprinting areas on both sides based on the priority imprinting area.

[0117] The two-sided imprinting areas refer to the imprinting areas on either side of the priority imprinting area on the flexographic printing plate. The two-sided imprinting areas are obtained by using a laser emitter to locate and identify the position of the priority imprinting area on the flexographic printing plate, and then finding the adjacent imprinting areas on both sides of that area.

[0118] Step 182: Locate the boundary line between the priority imprinting area and the imprinting areas on both sides.

[0119] The boundary line refers to the dividing line between the preferred printing area and the two adjacent printing areas on the flexographic printing plate. This boundary line is determined by scanning the surface of the flexographic printing plate with a laser emitter, extracting the boundary contours of the preferred printing area and the two adjacent printing areas using an edge detection algorithm, and then determining the position of the boundary line through geometric calculations.

[0120] Step 183: Control the pneumatic adsorption device corresponding to the current pneumatic adsorption device number to move to the boundary line of the area within the priority imprinting area, and then control the pneumatic adsorption device corresponding to the current pneumatic adsorption device number to adhere to the priority imprinting area.

[0121] Control the pneumatic adsorption device corresponding to the current pneumatic adsorption device number to relax the suction force in the priority imprinting area, control the robotic arm to move the pneumatic adsorption device in the priority imprinting area to the boundary line of the area, and then control the pneumatic adsorption device to adhere to the priority imprinting area.

[0122] Step 184: Determine the imprinting direction on both sides based on the priority imprinting area and the imprinting areas on both sides. The imprinting direction on both sides is the moving imprinting direction within the imprinting areas on both sides from the side closer to the priority imprinting area to the side farther away from the priority imprinting area.

[0123] Because the two imprinting areas on both sides contain two regions, the imprinting directions on both sides also contain two moving imprinting directions.

[0124] Step 185: Control the robotic arms corresponding to the two imprinting areas respectively to apply the corresponding imprinting pressure to the two imprinting areas according to their respective imprinting directions.

[0125] This also includes: Step 58: When the pneumatic adsorption device is controlled to hold the flexible printing plate, the pneumatic adsorption device is used to adsorb the plate according to the preset strong suction power.

[0126] Strong suction refers to the maximum rated suction force that a pneumatic adsorption device can generate to hold and fix a flexible printing plate. This suction force is obtained by pre-setting by those skilled in the art.

[0127] Step 59: When the robotic arm moves the flexible printing plate and initially adheres it to the curved substrate, the pneumatic adsorption device is used in conjunction with the robotic arm to adhere the plate according to the preset weak suction level.

[0128] The weak suction power refers to the minimum rated suction force generated by the pneumatic adsorption device used to initially bond the flexible printing plate to the curved substrate with the robotic arm, ensuring that the flexible printing plate does not fall off. This suction power is preset by those skilled in the art and is typically set to 20% to 40% of the strong suction power.

[0129] Based on the same inventive concept, embodiments of the present invention provide a holographic pattern seamless embossing system suitable for curved substrates.

[0130] A seamless holographic pattern embossing system suitable for curved substrates includes: The acquisition module is used to acquire real-time gap, reaction force, real-time pressure, device distance, and back view image; The memory stores a computer program that can be loaded by a processor and executed to provide a seamless holographic pattern imprinting method suitable for curved substrates. The processor loads and executes programs from memory.

[0131] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional modules is used as an example. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working process of the system, device, and unit described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0132] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for seamless holographic pattern imprinting suitable for curved substrates, characterized in that, include: Step 1: Perform surface scanning on the curved substrate to be imprinted to obtain the surface curvature curve of the imprinting surface. The surface curvature curve is a mapping curve between the surface position and the curvature. Step 2: Divide the curvature range according to the preset allowable curvature fluctuation range based on the curvature curve of the imprinted surface; Step 3: Divide the surface position according to the curvature range to obtain the segmented pressure region and the segmented average curvature; Step 4: Find the corresponding imprinting pressure in the preset curvature pressure database based on the segmented average curvature; Step 5: Control the corresponding pneumatic adsorption device to pick up the flexible printing plate area corresponding to the segmented pressure area, then control the robotic arm to move the flexible printing plate and the curved substrate to bond, and apply the corresponding printing pressure to the flexible printing plate area corresponding to the segmented pressure area after the bonding process.

2. The seamless holographic pattern imprinting method for curved substrates according to claim 1, characterized in that, Methods for performing surface scanning on the curved substrate to be imprinted include: Step 10: Clean the embossed surface of the curved substrate; Step 11: Control the plasma jet array to perform low-temperature activation treatment on the imprint surface.

3. The seamless holographic pattern imprinting method for curved substrates according to claim 1, characterized in that, Methods for controlling the movement of a robotic arm to bond flexible printing plates and curved substrates include: Step 50: Obtain the real-time gap between the flexible printing plate and the curved substrate; Step 51: When the real-time gap falls within the preset gap range, control the robotic arm to apply the corresponding imprinting pressure to the area of ​​the flexible printing plate corresponding to the segmented pressure area. Step 52: When the real-time gap does not fall within the preset gap range, the real-time gap that does not fall within the preset gap range is defined as an abnormal gap, and the segmented pressure area corresponding to the abnormal gap is defined as an abnormal segmented area. Step 53: Obtain the area of ​​the flexible printing plate that needs to be laminated corresponding to the abnormal segmentation area; Step 54: Locate the corresponding pneumatic adsorption device number based on the area to be bonded; Step 55: Control the robotic arm to push the area to be bonded corresponding to the number of the pneumatic adsorption device, and obtain the reaction force of the robotic arm in the area to be bonded; Step 56: When the reaction force exceeds the preset safety pressure, output a preset alarm signal; Step 57: When the reaction force is less than the safety pressure, continue to push the area to be bonded corresponding to the number of the pneumatic adsorption device until the real-time gap falls within the gap range or the reaction force is greater than the safety pressure.

4. The seamless holographic pattern imprinting method for curved substrates according to claim 3, characterized in that, It also includes a solution for when the reaction force exceeds the preset safety pressure, the method of which includes: Step 560: Perform curvature change analysis based on the surface curvature curve to obtain the abnormal curvature change pattern corresponding to the abnormal segmented region; Step 561: When the abnormal curvature change pattern is a preset concave pattern, the abnormal segmented region corresponding to the curvature change pattern is defined as a concave region. Step 562: Locate the mating areas on both sides based on the mating area corresponding to the concave area; Step 563: Locate the corresponding pneumatic adsorption device numbers on both sides based on the bonding areas on both sides; Step 564: Control the pneumatic adsorption device corresponding to the number of the pneumatic adsorption device to relax the suction between the pneumatic adsorption device and the area to be bonded, and then control the robotic arm to push the bonding areas on both sides corresponding to the numbers of the pneumatic adsorption devices on both sides in a preset inward moving direction, wherein the inward moving direction is the direction of the bonding areas on both sides toward the area to be bonded. Step 565: Obtain the real-time pressure feedback after relaxation on the pneumatic adsorption device corresponding to the pneumatic adsorption device number. Step 566: When the real-time pressure is less than the safe pressure, continue to push the area to be bonded corresponding to the number of the pneumatic adsorption device; Step 567: When the real-time pressure is at a safe pressure, stop pushing the area to be bonded corresponding to the number of the pneumatic adsorption device; Step 568: When the real-time gap does not fall within the gap range, repeat steps 55 to 565 until the real-time gap falls within the gap range.

5. The seamless holographic pattern imprinting method for curved substrates according to claim 4, characterized in that, The method for controlling the robotic arm to push the two sides of the pneumatic adsorption device corresponding to the numbered areas on both sides in a preset inward moving direction includes: Step 5640: Obtain the device distance between the pneumatic adsorption device corresponding to the pneumatic adsorption device number and the pneumatic adsorption devices corresponding to the pneumatic adsorption device numbers on both sides. Step 5641: When the device distance is 0, control the pneumatic adsorption devices corresponding to the numbers on both sides to relax the suction between the two sides of the contact area, and then move them in the contact area on both sides in an outward moving direction. The outward moving direction is the direction in which the contact area on both sides moves away from the area to be contacted. Control the pneumatic adsorption devices corresponding to the numbers on both sides to hold the contact area on both sides. Repeat steps 564 to 568 until the gap falls into the gap range in real time.

6. The seamless holographic pattern imprinting method for curved substrates according to claim 4, characterized in that, It also includes a verification method for determining whether to control the robotic arm to push the contact areas corresponding to the pneumatic adsorption devices on both sides in a preset inward moving direction when the reaction force exceeds the preset safety pressure. This method includes: Step 5642: Obtain the back image of the flexographic printing plate; Step 5643: Based on the back image of the flexible printing plate, find the preset imprinting border on the imprinting surface corresponding to the curved substrate; Step 5644: When the imprinted border is not present, control the robotic arm to push the two sides of the bonding area corresponding to the numbers of the pneumatic adsorption devices on both sides in the inward moving direction; Step 5645: When the imprinting border exists, perform a horizontal line scan on the imprinting surface to obtain the horizontal length of the imprinting surface on each horizontal line; Step 5646: Match the horizontal length with the preset horizontal length of the printing plate based on the same horizontal line; Step 5647: When the horizontal length does not match the horizontal length of the printing plate, re-acquire the curved substrate to be imprinted.

7. The seamless holographic pattern imprinting method for curved substrates according to claim 1, characterized in that, Also includes: Step 12: Analyze the curvature changes based on the surface curvature curve to obtain the curvature change patterns corresponding to the segmented pressure regions; Step 13: When the curvature change pattern is a preset convex surface pattern, the segmented pressure region corresponding to the curvature change pattern is defined as a convex surface region; Step 14: Filter out the average curvature of the convex region based on the segmented average curvature and the convex region; Step 15: Select the convex area with the largest average curvature based on the average curvature of the convex surface, and define the area of ​​the flexible printing plate corresponding to the convex surface area as the priority imprinting area. Step 16: Determine other imprinting areas based on the preferred imprinting area; Step 17: Determine the imprinting order based on the priority imprinting area and other imprinting areas. The imprinting order is to first imprint the priority imprinting area, and then imprint the other imprinting areas on both sides of the priority imprinting area one by one. Step 18: Control the robotic arm to imprint according to the imprinting sequence.

8. The seamless holographic pattern imprinting method for curved substrates according to claim 7, characterized in that, The specific methods for controlling the robotic arm to perform the imprinting according to the imprinting sequence include: Step 180: After the robotic arm applies the corresponding imprinting pressure to the priority imprinting area, it finds the corresponding current pneumatic adsorption device number based on the priority imprinting area and controls the pneumatic adsorption device corresponding to the current pneumatic adsorption device number to relax the suction. Step 181: Locate the imprinting areas on both sides based on the priority imprinting area; Step 182: Locate the boundary line between the priority imprinting area and the imprinting areas on both sides; Step 183: Control the pneumatic adsorption device corresponding to the current pneumatic adsorption device number to move to the boundary line of the area within the priority imprinting area, and then control the pneumatic adsorption device corresponding to the current pneumatic adsorption device number to adhere to the priority imprinting area. Step 184: Determine the imprinting direction on both sides based on the preferred imprinting area and the imprinting areas on both sides. The imprinting direction on both sides is the moving imprinting direction within the imprinting areas on both sides from the side closer to the preferred imprinting area to the side farther away from the preferred imprinting area. Step 185: Control the robotic arms corresponding to the two imprinting areas respectively to apply the corresponding imprinting pressure to the two imprinting areas according to their respective imprinting directions.

9. A method for seamless holographic pattern imprinting suitable for curved substrates according to claim 1, characterized in that, Also includes: Step 58: When the pneumatic adsorption device is controlled to hold the flexible printing plate, the pneumatic adsorption device is used to adsorb according to the preset strong suction force. Step 59: When the robotic arm moves the flexible printing plate and initially adheres it to the curved substrate, the pneumatic adsorption device is used in conjunction with the robotic arm to adhere the plate according to the preset weak suction level.

10. A seamless holographic pattern embossing system suitable for curved substrates, characterized in that, include: The acquisition module is used to acquire real-time gap, reaction force, real-time pressure, device distance, and back view image; A memory for storing a program of a seamless holographic pattern imprinting method for curved substrates as described in any one of claims 1 to 9; The processor loads and executes programs from memory.

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