Laser lift-off device and laser lift-off method for stretchable display panel

Abstract

The present application discloses a laser lift-off device and a laser lift-off method for a stretchable display panel. The laser lift-off device is used for laser lift-off of a flexible substrate formed on one side of a rigid substrate in a stretchable display panel from the rigid substrate. The flexible substrate includes a plurality of island regions arranged in an array and a bridge region connecting two adjacent island regions. The laser lift-off device includes: a laser source; and a lens assembly disposed between the laser source and the rigid substrate. The lens assembly includes a light-transmitting plate and a plurality of convex lenses disposed on the light-transmitting plate corresponding to the bridge regions, wherein the orthographic projections of the convex lenses on the flexible substrate at least partially cover the bridge regions. The laser lift-off device locally adjusts the laser irradiation intensity through the lens assembly, thereby increasing the laser irradiation intensity on the bridge region and reducing the force required to lift the bridge region from the rigid substrate. Thus, the island and bridge regions of the flexible substrate are separated from the rigid substrate under similar forces, thereby avoiding the defect of the bridge region being difficult to separate from the rigid substrate and thus being damaged.

Description

Technical Field

[0001] The present application belongs to the field of stretchable display technology, and in particular relates to a laser lift-off device and a laser lift-off method for a stretchable display panel. Background Art

[0002] As a new form of flexible display application, stretchable display panels have received widespread attention in recent years and have the characteristics of being able to realize display panels in various forms.

[0003] In related technologies, stretchable display panels use an island-bridge structure. Typically, a flexible substrate is formed on a rigid substrate, and then island and bridge regions are fabricated on the flexible substrate. The flexible substrate is then separated from the rigid substrate using a laser lift-off (LLO) process. However, during the LLO process, the island regions are easily separated while the bridge regions are difficult to separate. This can lead to the bridge regions breaking and damaging the stretchable display panel.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Summary of the Invention

[0005] This application aims to at least partially address the technical problem of the bridge region being easily broken during the laser lift-off process of a stretchable display panel, which can lead to damage to the stretchable display panel. To this end, this application provides a laser lift-off device and a laser lift-off method for a stretchable display panel.

[0006] An embodiment of the present application provides a laser lift-off device for laser lift-off of a flexible substrate formed on one side of a rigid substrate in a stretchable display panel from the rigid substrate. The flexible substrate includes a plurality of island regions arranged in an array and a bridge region connecting two adjacent island regions. The laser lift-off device includes:

[0007] a laser source; and,

[0008] A lens assembly is arranged between the laser source and the rigid substrate, and includes a light-transmitting plate and a plurality of convex lenses arranged on the light-transmitting plate corresponding to the bridge area, wherein the orthographic projections of the convex lenses on the flexible substrate at least partially cover the bridge area.

[0009] In some embodiments, an orthographic projection of the focus of the convex lens on the flexible substrate is located in the bridge region and the focus is located outside the bridge region.

[0010] In some embodiments, the laser imaging area formed by focusing the laser beam through the convex lens covers the bridge area, and the symmetry axis of the laser imaging area coincides with the symmetry axis of the bridge area; the laser imaging area and the bridge area are respectively arranged in an axisymmetric manner with the peeling direction of the flexible substrate as the symmetry axis.

[0011] In some embodiments, the flexible substrate further includes an opening area located between the island area and the bridge area, and an orthographic projection of the convex lens on the flexible substrate is at least partially located in the opening area.

[0012] In some embodiments, the orthographic projection of the convex lens on the flexible substrate at least partially covers a connection portion of the island area for connecting the bridge area.

[0013] In some embodiments, the area of ​​the connecting portion accounts for 5% to 10% of the area of ​​the island region.

[0014] In some embodiments, adjacent convex lenses abut against each other.

[0015] In some embodiments, the orthographic projection of the junction between adjacent convex lenses on the flexible substrate is located in the opening area.

[0016] In some embodiments, the orthographic projection of the convex lens on the flexible substrate avoids the island area.

[0017] In some embodiments, the outer contour of the convex lens is circular, elliptical, rectangular or irregular.

[0018] The present application also provides a laser lift-off method for a stretchable display panel, which includes the following steps:

[0019] a substrate preparation step, providing a rigid substrate, and forming a flexible substrate on a first side of the rigid substrate, wherein the flexible substrate includes a plurality of island regions arranged in an array and a bridge region connecting two adjacent island regions;

[0020] a functional area preparation step of forming a pixel island on a side of the island area away from the rigid substrate, and forming a conductive connection bridge on a side of the bridge area away from the rigid substrate;

[0021] a laser lift-off step, providing a lens assembly, wherein the lens assembly is located between a laser source and the second side of the rigid substrate, and laser light emitted by the laser source is irradiated onto the second side of the rigid substrate through the lens assembly to lift the rigid substrate off the flexible substrate;

[0022] The lens assembly includes a light-transmitting plate and a plurality of convex lenses arranged on the light-transmitting plate corresponding to the bridge area, and the orthographic projections of the convex lenses on the flexible substrate cover the bridge area.

[0023] The embodiments of the present application have at least the following beneficial effects:

[0024] The above-mentioned laser peeling equipment is equipped with a lens assembly between the laser source and the rigid substrate. The laser irradiation intensity is locally adjusted through the lens assembly to apply laser irradiation effects of different intensities to different areas on the stretchable display panel, thereby enhancing the laser irradiation intensity received by the bridge area, reducing the force required for peeling the bridge area from the rigid substrate, and reducing the difference in force required for the bridge area and the island area to be separated from the rigid substrate glass. Therefore, the island area and the bridge area of ​​the flexible substrate are separated from the rigid substrate under similar forces, thereby avoiding the defect that the bridge area is not easily separated from the rigid substrate and is damaged. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, a brief introduction will be given below to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0026] Figure 1 A schematic diagram showing the arrangement position of the lens assembly in the laser lift-off device according to an embodiment of the present application is shown;

[0027] Figure 2 A schematic diagram showing the relative positions of an array unit and a flexible substrate in a lens assembly in Example 1 of the present application is shown;

[0028] Figure 3 Shown Figure 2 A top view of the lens assembly in FIG.

[0029] Figure 4 Shown Figure 3 a cross-sectional view of the middle lens assembly;

[0030] Figure 5 A schematic diagram showing the relative positions of an array unit and a flexible substrate in a lens assembly in the second embodiment of the present application is shown;

[0031] Figure 6 Shown Figure 5 A top view of the lens assembly in FIG.

[0032] Figure 7 A schematic diagram showing the relative positions of an array unit and a flexible substrate in a lens assembly in a third embodiment of the present application is shown;

[0033] Figure 8 Shown Figure 7 A top view of the lens assembly in FIG.

[0034] Figure 9 The focusing principle diagram of the lens in the embodiment of the present application is shown;

[0035] Figure 10 Schematic diagram of the structure of the lens in the embodiment of the present application is shown;

[0036] Figure 11 A top view of the flexible substrate in the fourth embodiment of the present application is shown;

[0037] Figure 12 FIG2 shows a top view of the flexible substrate in the fifth embodiment of the present application;

[0038] Figure 13 A top view of the flexible substrate in the sixth embodiment of the present application is shown.

[0039] Reference numerals:

[0040] 100, rigid substrate; 200, flexible substrate; 210, island area; 220, bridge area; 230, opening area; 300, lens assembly; 310, light-transmitting plate; 320, convex lens; 321, focus; 400, laser source; 410, laser imaging area. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0042] In addition, this application may repeat reference numbers and / or reference letters in different examples. This repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, this application provides examples of various specific processes and materials, but those of ordinary skill in the art will recognize the application of other processes and / or the use of other materials.

[0043] The present application is described below with reference to specific embodiments and with reference to the accompanying drawings:

[0044] The present application embodiment provides a laser lift-off device, such as Figures 1 to 7As shown, the laser lift-off device is used for laser lift-off of a flexible substrate 200 formed on one side of a rigid substrate 100 in a stretchable display panel from the rigid substrate 100. The flexible substrate 200 includes a plurality of island regions 210 arranged in an array and a bridge region 220 connecting two adjacent island regions 210. The laser lift-off device includes a laser source 400 and a lens assembly 300. The lens assembly 300 is disposed between the laser source 400 and the rigid substrate 100. The lens assembly 300 includes a light-transmitting plate 310 and a plurality of convex lenses 320 disposed on the light-transmitting plate 310 corresponding to the bridge regions 220. The orthographic projections of the convex lenses 320 on the flexible substrate 200 at least partially cover the bridge regions 220.

[0045] The laser lift-off device provided in the embodiment of the present application is as follows: Figure 1 As shown, a lens assembly 300 is provided between the laser source 400 and the rigid substrate 100. The laser irradiation intensity is locally adjusted through the lens assembly 300 to apply laser irradiation effects of different intensities to different areas on the stretchable display panel, thereby enhancing the laser irradiation intensity received by the bridge area 220, reducing the force required for the bridge area 220 to be peeled off from the rigid substrate 100, and reducing the difference in force required for the bridge area 220 and the island area 210 to be separated from the glass of the rigid substrate 100. Therefore, under similar forces, the island area 210 and the bridge area 220 of the flexible substrate 200 are separated from the rigid substrate 100, thereby avoiding the defect that the bridge area 220 is difficult to separate from the rigid substrate 100 and is damaged.

[0046] In this application, if Figure 2 as well as Figures 11 to 13 As shown, the stretchable display panel includes two structural parts: island area 210 and bridge area 220. Pixel islands, which contain a multi-layer structure including electrodes and light-emitting elements, are formed on island area 210 and are the main part providing the display function. Conductive bridges are formed on bridge area 220 to connect the pixel islands. Bridge area 220 connects the island areas 210 and provides a certain degree of deformation capability, which is the main part providing the stretchability function.

[0047] In the stretchable display panel of the embodiment of the present application, the island area 210 and the bridge area 220 are designed in different ways. For example, in Figure 2 In the embodiment 1 shown, each island region 210 of the stretchable display panel is a same quadrilateral, and adjacent island regions 210 are connected by bridge regions 220. Figure 11 In the fourth embodiment shown, the island regions 210 of the stretchable display panel are circular and elliptical, and adjacent island regions 210 are connected by bridge regions 220. Figure 12 In the fifth embodiment shown, the island regions 210 of the stretchable display panel are quadrilaterals of different sizes arranged at intervals, and adjacent island regions 210 are connected by bridge regions 220. Figure 13In the sixth embodiment shown, the island area 210 of the stretchable display panel is fan-shaped or semicircular, wherein each line represents a multi-layer structure such as electrodes, light-emitting elements, and circuits formed on the island area 210, and the fan-shaped or semicircular island areas 210 are connected by bridge areas 220. The laser lift-off device of the present application can be used for stretchable display panel structures including but not limited to those shown in the above embodiments. In the following description of the present application, Figure 2 The laser lift-off device of the present application is exemplified by taking the stretchable display panel shown as an example.

[0048] During the preparation of a stretchable display panel, a flexible substrate 200 comprising island regions 210 and bridge regions 220 is first formed on a rigid substrate 100. Corresponding functional layers are then stacked on the island regions 210 and bridge regions 220 to form the stretchable display panel. Subsequently, a laser lift-off process is used to separate the stretchable display panel from the rigid substrate 100, specifically separating the island regions 210 and bridge regions 220 of the flexible substrate 200 from the rigid substrate 100. Due to differences in stacking structure, surface area, and peripheral opening distribution on the island regions 210 and bridge regions 220, the laser irradiation energy received by different regions of the flexible substrate 200 and the rigid substrate 100 during the laser lift-off process may be uneven. This means that the island regions 210 and bridge regions 220 receive different laser irradiation energies, resulting in different forces required to separate the stretchable display panel from the rigid substrate 100. In particular, the bridge regions 220 have a smaller surface area than the island regions 210, requiring a higher unit laser energy to separate them from the rigid substrate 100. In the next step, if the same force is used to separate the stretchable display panel from the rigid substrate 100, it is likely that the island regions 210 will separate while the bridge regions 220 will not. Increasing the separation force can easily cause the bridge regions 220 to break, damaging the stretchable display panel. Increasing the laser irradiation intensity overall can easily lead to excessive laser irradiation intensity on the island regions 210, damaging their structure.

[0049] In the laser lift-off device of the present application, a lens assembly 300 is provided between the laser source 400 and the rigid substrate 100, that is, an optical element with the function of adjusting the light intensity is added to the optical path, so that the laser line emitted by the laser source 400 passes through the laser source 400 and the rigid substrate 100 in turn and acts on the island area 210 and the bridge area 220. The intensity of the laser irradiated on the island area 210 and the bridge area 220 is adjusted by the lens assembly 300, and the intensity of the laser irradiated on the bridge area 220 is increased by the focusing effect of the convex lens 320, so as to achieve different intensities of laser irradiation on different areas of the stretchable display panel, and balance the intensity of the laser irradiation on the island area 210 and the bridge area 220. 20 is subjected to the difference of laser irradiation effect, slowing down or eliminating the uneven phenomenon of laser irradiation effect on the stretchable display panel, so as to reduce the magnitude of the force required for separating the bridge area 220 from the rigid substrate 100, and make the magnitude of the force required for separating the bridge area 220 from the rigid substrate 100 and the magnitude of the force required for separating the island area 210 from the rigid substrate 100 the same or similar, so that under the same magnitude of force, the island area 210 and the bridge area 220 can be easily separated from the rigid substrate 100, avoiding the situation that the bridge area 220 is difficult to separate from the rigid substrate 100, causing the bridge area 220 to break and resulting in damage to the stretchable display panel.

[0050] In the laser lift-off device of the present application, the rigid substrate 100 may be a glass substrate. The glass substrate is light-transmissive and does not affect the laser penetrating the glass substrate to act on the flexible substrate 200.

[0051] In the following embodiments of the present application, the flexible substrate 200 of the stretchable display panel can be made of polyimide (PI). In other embodiments of practical applications, the flexible substrate 200 can also be made of other organic materials, such as polymer materials such as polyethylene terephthalate (PET) or polycarbonate (PC).

[0052] In the laser lift-off device of the present application, since the orthographic projection of the convex lenses 320 of the lens assembly 300 on the flexible substrate 200 needs to cover the bridge region 220, the arrangement of the convex lenses 320 of the lens assembly 300 on the light-transmitting plate 310 is similar to the arrangement of the bridge region 220 on the flexible substrate 200. That is, the convex lenses 320 are arranged in an array on the light-transmitting plate 310. In the following embodiments of the present application, one array unit in the lens assembly 300 is used as an example to exemplify the lens assembly 300 and the laser lift-off device of the present application.

[0053] In the laser stripping device of the present application, the lens assembly 300 is an optical element that can locally enhance the intensity of light. The structure of the lens assembly 300 is related to the form of the stretchable display panel. For stretchable display panels of different forms, different lens assemblies 300 are required to match the stretchable display panel. When performing laser stripping on stretchable display panels of different forms, the laser stripping device of the present application only needs to replace the corresponding lens assembly 300, and no other structures need to be adjusted or replaced, and the operation difficulty is relatively low. At the same time, the existing laser stripping equipment can also be modified based on the inventive concept of the present application. The lens assembly 300 can be added to the existing laser stripping equipment. The modification cost of the laser stripping equipment is low, which can greatly reduce the equipment cost.

[0054] As an optional implementation manner, the orthographic projection of the focus 321 of the convex lens 320 on the flexible substrate 200 is located in the bridge area 220 and the focus 321 is located outside the bridge area 220 .

[0055] In this application, if Figure 2 、 Figure 5 as well as Figure 7 As shown, due to the focusing characteristics of convex lens 320, when the laser light emitted by laser source 400 passes through convex lens 320, the laser light is focused toward focal point 321 through the refraction of convex lens 320, so that the orthographic projection of focal point 321 of convex lens 320 on flexible substrate 200 is located at bridge region 220. This ensures that convex lens 320 focuses the laser light onto bridge region 220, thereby increasing the laser energy irradiated onto bridge region 220 and the energy of the laser light acting on the interface between bridge region 220 and rigid substrate 100. The laser light is used to break the chemical bonds at the interface between bridge region 220 and rigid substrate 100, thereby achieving the purpose of peeling bridge region 220 from rigid substrate 100. At the same time, the focal point 321 is located outside bridge region 220 to avoid the laser light being focused onto focal point 321 and located on bridge region 220, which would cause the bridge region 220 located at focal point 321 to be damaged by excessive laser energy.

[0056] As an optional embodiment, the laser imaging area 410 formed by focusing the laser beam through the convex lens 320 covers the bridge area 220, and the symmetry axis of the laser imaging area 410 coincides with the symmetry axis of the bridge area 220; the laser imaging area 410 and the bridge area 220 are respectively arranged in an axially symmetrical manner with the peeling direction of the flexible substrate 200 as the symmetry axis.

[0057] In this application, if Figure 2 、 Figure 5 、 Figure 7 as well as Figure 9As shown, according to the focusing characteristics of the convex lens 320, by adjusting the distance between the lens assembly 300 and the rigid substrate 100, the laser imaging area 410 formed by focusing the laser beam through the convex lens 320 covers the bridge area 220, so that the bridge area 220 can be completely irradiated by the laser, and the laser acts on the interface between the entire bridge area 220 and the rigid substrate 100, to ensure that any part of the bridge area 220 can be easily peeled off from the rigid substrate 100.

[0058] In this application, if Figure 2 、 Figure 5 as well as Figure 7 As shown, for a single bridge area 220, the symmetry axis of the laser imaging area 410 is made to coincide with the symmetry axis of the bridge area 220, so that the laser energy received by each part of the bridge area 220 is relatively balanced, thus avoiding the bridge area 220 being torn and damaged due to uneven local force during peeling. Figure 2 Taking the embodiment shown as an example, the symmetry axis X1 of the laser imaging area 410 of the left and right convex lenses 320 in the figure coincides with the symmetry axis X1 of the left and right bridge areas 220, then the laser energies received by the bridge areas 220 on both sides of the symmetry axis X1 are close, and the energies required for peeling are also relatively close; at the same time, the symmetry axis Y1 of the laser imaging area 410 of the upper and lower convex lenses 320 in the figure coincides with the symmetry axis Y1 of the upper and lower bridge areas 220, then the laser energies received by the bridge areas 220 on both sides of the symmetry axis Y1 are close, and the energies required for peeling are also relatively close.

[0059] In this application, if Figure 2 、 Figure 5 as well as Figure 7 As shown, for the bridge region 220 of an array unit, the laser imaging area 410 and the bridge region 220 are arranged symmetrically about the peeling direction of the flexible substrate 200. This ensures that the laser energy received by the bridge region 220 along the same separation line is relatively even during the peeling process. In this application, the peeling line is defined as the linear separation portion formed by the gradual peeling of the flexible substrate 200 and the rigid substrate 100, perpendicular to the peeling direction.

[0060] In this application, Figure 2For example, four convex lenses 320 are arranged corresponding to the four islands 210. The orthographic projections of the four convex lenses 320 (i.e., the orthographic projections of the convex lenses 320 on the flexible substrate 200) on the flexible substrate 200 cover the bridge areas 220 between the islands 210. Two adjacent convex lenses 320 abut against each other in the opening area 230 between the four islands 210. In addition, the two convex lenses 320 are symmetrically arranged in a first direction (e.g., the horizontal X direction), and their symmetry axis X1 passes through the intersection point O of the diagonals of the four islands 210. In addition, the two convex lenses 320 are symmetrically arranged in the second direction (for example, the vertical Y direction), and their symmetry axis Y1 passes through the diagonal intersection O of the four island areas 210, wherein the diagonal intersection O is the intersection of the diagonals Z1 and Z2 of the four island areas 210. Such a design is conducive to the relative uniformity of laser energy between adjacent island areas 210, and the relative uniformity of laser energy between adjacent bridge areas 220, thereby avoiding premature peeling or tearing of individual island areas 210 or bridge areas 220 due to excessive laser energy.

[0061] In the present application, in order to make the laser energy received by each part of the bridge area 220 basically close while avoiding excessive laser energy received locally, the position of the center of the convex lens 320 relative to the bridge area 220 can be appropriately adjusted so that the laser line focused by the convex lens 320 is more evenly distributed in the bridge area 220.

[0062] In this application, Figure 2 For example, in a symmetrical arrangement of two convex lenses 320 in a first direction (e.g., the horizontal X direction), the spacing X2 between the center points of the two convex lenses 320 is greater than the spacing X3 between the corresponding bridge areas 220. This design facilitates focusing the laser originally irradiated on the opening area 230 onto the bridge area 220, thereby increasing the unit laser energy of the bridge area 220 and reducing the difficulty of peeling the bridge area 220 from the rigid substrate 100. At the same time, the bridge area 220 is shielded from the high energy at the center point of the convex lens 320 (the center point generally has higher focusing power than other areas), thus preventing the bridge area 220 corresponding to the center point from premature peeling or tearing due to excessive laser energy. Similarly, in a symmetrical arrangement of two convex lenses 320 in a second direction (e.g., the horizontal Y direction), the spacing between the center points of the two convex lenses 320 is greater than the spacing between the corresponding bridge areas 220.

[0063] As an optional embodiment, the flexible substrate 200 further includes an opening area 230 located between the island area 210 and the bridge area 220 , and the orthographic projection of the convex lens 320 on the flexible substrate 200 is at least partially located in the opening area 230 .

[0064] In this application, if Figure 2As shown, an opening area 230 is distributed between the island area 210 and the bridge area 220 of the flexible substrate 200. No flexible substrate 200 material is distributed in the opening area 230. In a stretchable display panel, the opening area 230 can provide the stretchable display panel with the deformation space required for stretching.

[0065] When the stretchable display panel formed on the rigid substrate 100 is irradiated from the rigid substrate 100 side by the laser source 400, the laser energy irradiated to the opening area 230 is dissipated and not absorbed by the PI because the opening area 230 is not covered by the PI. On the one hand, this causes a waste of laser energy. On the other hand, the laser energy obtained by the bridge area 220 is small and it is difficult to separate from the rigid substrate. In the laser lift-off setting of the present application, as shown in FIG. Figure 2 As shown, the orthographic projection of the convex lens 320 on the flexible substrate 200 is located in the opening area 230. Preferably, the orthographic projection of the convex lens 320 on the flexible substrate 200 can cover the opening area 230 as much as possible. Through the focusing effect of the convex lens 320, the laser originally irradiated to the opening area 230 is focused onto the flexible substrate 200, especially onto the bridge area 220 of the flexible substrate 200. On the one hand, the utilization rate of the laser energy can be improved; at the same time, in the stretchable display panel, since the surface area of ​​the bridge area 220 is smaller than that of the island area 210, the bridge area 220 requires a higher unit laser energy to be peeled off from the rigid substrate 100. By focusing the laser originally irradiated on the opening area 230 to the bridge area 220, the unit laser energy of the bridge area 220 is increased, thereby reducing the difficulty of peeling the bridge area 220 from the rigid substrate 100.

[0066] As an optional implementation manner, the orthographic projection of the convex lens 320 on the flexible substrate 200 at least partially covers the connection portion of the island area 210 for connecting the bridge area 220 .

[0067] like Figure 5 As shown, in the stretchable display panel, the island area 210 is provided with a connecting portion, which is used to connect to the bridge area 220. During the laser stripping process of the stretchable display panel, there may be a problem that the connection between the island area 210 and the bridge area 220 is difficult to strip. In order to avoid the occurrence of the defect of the connection between the island area 210 and the bridge area 220 being difficult to strip, as shown in FIG. Figure 5 As shown, the orthographic projection of the convex lens 320 on the flexible substrate 200 at least partially covers the connection portion of the island area 210, even if the focusing area of ​​the convex lens 320 is slightly larger than the area of ​​the bridge area 220 and includes a portion of the island area 210. In this way, the laser energy irradiated to the connection portion is increased by the convex lens 320, thereby reducing the difficulty of peeling at the connection between the island area 210 and the bridge area 220.

[0068] As an optional implementation manner, the area of ​​the connection portion accounts for 5% to 10% of the area of ​​the island area 210 .

[0069] In this application, if Figure 5 As shown, the connection portion can occupy 5% to 10% of the area of ​​the island area 210, even if the focusing area of ​​the convex lens 320 includes 5% to 10% of the area of ​​the island area 210, thereby ensuring that the connection between the island area 210 and the bridge area 220 is subjected to sufficient laser energy, ensuring that the connection portion of the island area 210 and the rigid substrate 100 can be smoothly peeled off.

[0070] As an optional implementation, adjacent convex lenses 320 abut against each other.

[0071] In this application, if Figures 2 to 8 As shown, in the lens assembly 300, adjacent convex lenses 320 are abutted against each other, so that the focusing area of ​​the convex lens 320 can be expanded as much as possible, so that the convex lens 320 can fully utilize the laser energy of the opening area 230, and focus the laser originally irradiated to the opening area 230 to the connection part of the bridge area 220 and the island area 210, thereby improving the utilization rate of the laser energy.

[0072] As an optional implementation manner, the orthographic projection of the contact point between adjacent convex lenses 320 on the flexible substrate 200 is located in the opening area 230 .

[0073] In this application, if Figures 2 to 8 As shown, according to the focusing principle of the convex lens 320, the laser irradiated to the edge portion of the convex lens 320 is subjected to the focusing effect of the convex lens 320, changes the irradiation direction, and is focused on the middle portion of the convex lens 320. Therefore, the laser energy in the area corresponding to the edge portion of the convex lens 320 is reduced or even eliminated. Therefore, the orthographic projection of the abutment between adjacent convex lenses 320 on the flexible substrate 200 is located in the opening area 230. That is, most of the edge of the convex lens 320 can be located in the opening area 230, and the laser energy in the opening area 230 corresponding to the edge portion of the convex lens 320 is focused to the bridge area 220 corresponding to the middle portion (focusing area) of the convex lens 320, thereby improving the utilization effect and focusing effect of the laser energy.

[0074] As an optional implementation, the orthographic projection of the convex lens 320 on the flexible substrate 200 avoids the island area 210 .

[0075] In the laser lift-off device of the present application, the island area 210 can be easily peeled off from the rigid substrate 100 after being subjected to the laser energy preset by the laser source 400. In order to avoid the focusing effect of the convex lens 320 affecting the laser energy received by the island area 210, as shown in FIG. Figure 2 and Figure 7As shown, the orthographic projection of the convex lens 320 on the flexible substrate 200 avoids the island area 210, that is, the convex lens 320 of the lens assembly 300 is prevented from changing the laser energy received by the island area 210, thereby ensuring that the island area 210 can receive appropriate laser energy and ensuring the peeling effect of the island area 210 and the rigid substrate 100.

[0076] As an optional implementation, the outer contour of the convex lens 320 is circular, elliptical, rectangular or irregular.

[0077] In this application, if Figures 2 to 13 As shown, the island area 210 of the stretchable display panel has various morphological structures, and the array arrangement of the island area 210 on the flexible substrate 200 can also have various forms. In order to enable the convex lens 320 to better focus the laser on the bridge area 220 while avoiding affecting the laser energy received by the island area 210, the outer contour of the convex lens 320 can be adaptively changed according to the structural characteristics of the stretchable display panel. Figure 2 and Figure 5 As shown, the outer contour of the convex lens 320 can be an ellipse, such as Figure 7 As shown, the outer contour of the convex lens 320 can also be circular.

[0078] In other embodiments, the outer contour of the convex lens 320 may also be a rectangle, or a fan-shaped, star-shaped or other special-shaped outer contour.

[0079] In the present application, the circular convex lens 320 may be cut so that the outer contour of the convex lens 320 meets the design requirements.

[0080] In this application, in order to enable the convex lens 320 with different outer contours to achieve the focusing effect, the laser light around is focused to the middle area (focusing area), and the curvature of different parts of the surface of the convex lens 320 can be adaptively adjusted, or as shown in FIG. Figure 10 As shown, the convex lens 320 corresponding to the same bridge area 220 is formed by cutting and splicing multiple circular convex lenses 320, where the dotted line portion represents the focused light distribution formed by the uncut circular convex lens 320. This allows convex lenses 320 with different outer contours to all have a focusing effect, and the formed focusing area can be made to match the shape of the bridge area 220 as much as possible, focusing the laser energy in the area covered by the convex lens 320 to the bridge area 220 as much as possible, thereby improving the utilization rate of the laser energy and increasing the laser energy acting on the bridge area 220. In this application, the structure of the convex lens 320 corresponding to the bridge area 220 can be adjusted and configured accordingly according to the specific structure of the bridge area 220, and will not be repeated here.

[0081] Based on the same inventive concept, an embodiment of the present application further provides a laser lift-off method for a stretchable display panel, the laser lift-off method for a stretchable display panel comprising the following steps:

[0082] A substrate preparation step includes providing a rigid substrate 100 and forming a flexible substrate 200 on a first side of the rigid substrate 100 . The flexible substrate 200 includes a plurality of island regions 210 arranged in an array and a bridge region 220 connecting two adjacent island regions 210 .

[0083] A functional area preparation step is to form a pixel island on the side of the island area 210 away from the rigid substrate 100 and to form a connection bridge on the side of the bridge area 220 away from the rigid substrate 100;

[0084] In the laser lift-off step, a lens assembly 300 is provided. The lens assembly 300 is located between the laser source 400 and the second side of the rigid substrate 100. The laser light emitted by the laser source 400 is irradiated onto the second side of the rigid substrate 100 through the lens assembly 300 to lift the rigid substrate 100 off from the flexible substrate 200.

[0085] The lens assembly 300 includes a light-transmitting plate 310 and a plurality of convex lenses 320 disposed on the light-transmitting plate 310 corresponding to the bridge area 220 . The orthographic projections of the convex lenses 320 on the flexible substrate 200 cover the bridge area 220 .

[0086] In the laser lift-off method for the stretchable display panel, a lens assembly 300 is provided between the laser source 400 and the rigid substrate 100. The laser irradiation intensity is locally adjusted through the lens assembly 300 to apply laser irradiation effects of different intensities to different areas on the stretchable display panel, thereby enhancing the laser irradiation intensity received by the bridge area 220, reducing the force required to peel the bridge area 220 from the rigid substrate 100, and reducing the difference in force required to separate the bridge area 220 and the island area 210 from the glass of the rigid substrate 100. Therefore, under similar forces, the island area 210 and the bridge area 220 of the flexible substrate 200 are separated from the rigid substrate 100, thereby avoiding the defect that the bridge area 220 is difficult to separate from the rigid substrate 100 and is damaged.

[0087] In the laser stripping method of the stretchable display panel, a corresponding lens assembly 300 is prepared / selected according to the structure of the stretchable display panel, the lens assembly 300 is added to the laser stripping light path, and the distance between the lens assembly 300 and the light source and the rigid substrate 100 can be adjusted respectively, so that the convex lens 320 in the lens assembly 300 focuses the laser onto the bridge area 220, thereby increasing the laser energy received by the bridge area 220, so that the bridge area 220 and the island area 210 can be easily separated from the rigid substrate 100.

[0088] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0089] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise" and "counterclockwise" indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0090] It should be noted that all directional indications in the embodiments of the present application are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0091] In this application, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0092] In addition, the terms "first," "second," and so on, used in this application are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0093] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification.

[0094] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0095] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A laser lift-off device, characterized in that: The laser lift-off device is used for laser lift-off of a flexible substrate formed on one side of a rigid substrate in a stretchable display panel from the rigid substrate, wherein the flexible substrate includes a plurality of island regions arranged in an array and a bridge region connecting two adjacent island regions; The laser lift-off device comprises: Laser source; and, A lens assembly is arranged between the laser source and the rigid substrate, and includes a light-transmitting plate and a plurality of convex lenses arranged on the light-transmitting plate corresponding to the bridge area, wherein the orthographic projections of the convex lenses on the flexible substrate at least partially cover the bridge area.

2. The laser lift-off device according to claim 1, wherein: An orthographic projection of the focus of the convex lens on the flexible substrate is located in the bridge area, and the focus is located outside the bridge area.

3. The laser lift-off device according to claim 2, wherein: The laser beam emitted by the laser source is focused by the convex lens to form a laser imaging area covering the bridge area, and the symmetry axis of the laser imaging area coincides with the symmetry axis of the bridge area; the laser imaging area and the bridge area are respectively arranged axially symmetrically with the peeling direction of the flexible substrate as the symmetry axis.

4. The laser lift-off device according to any one of claims 1 to 3, wherein: The flexible substrate further includes an opening area located between the island area and the bridge area, and the orthographic projection of the convex lens on the flexible substrate is at least partially located in the opening area.

5. The laser lift-off device according to claim 4, wherein: The orthographic projection of the convex lens on the flexible substrate at least partially covers a connection portion of the island area for connecting the bridge area.

6. The laser lift-off device according to claim 5, wherein: The area of ​​the connecting portion accounts for 5% to 10% of the area of ​​the island region.

7. The laser lift-off device according to claim 4, wherein: Adjacent convex lenses abut against each other.

8. The laser lift-off device according to claim 7, wherein: The orthographic projection of the contact point between adjacent convex lenses on the flexible substrate is located in the opening area.

9. The laser lift-off device according to claim 4, wherein: The orthographic projection of the convex lens on the flexible substrate avoids the island area.

10. The laser lift-off device according to claim 4, wherein: The outer contour of the convex lens is circular, elliptical, rectangular or irregular.

11. A laser lift-off method for a stretchable display panel, characterized in that: The laser lift-off method for a stretchable display panel comprises the following steps: a substrate preparation step, providing a rigid substrate, and forming a flexible substrate on a first side of the rigid substrate, wherein the flexible substrate includes a plurality of island regions arranged in an array and a bridge region connecting two adjacent island regions; a functional area preparation step of forming a pixel island on a side of the island area away from the rigid substrate, and forming a conductive connection bridge on a side of the bridge area away from the rigid substrate; a laser lift-off step, providing a lens assembly, wherein the lens assembly is located between a laser source and the second side of the rigid substrate, and laser light emitted by the laser source is irradiated onto the second side of the rigid substrate through the lens assembly to lift the rigid substrate off the flexible substrate; The lens assembly includes a light-transmitting plate and a plurality of convex lenses arranged on the light-transmitting plate corresponding to the bridge area, and the orthographic projections of the convex lenses on the flexible substrate cover the bridge area.

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