Optical mask, laser stripping equipment and method for preparing flexible display device

Abstract

The present invention relates to an optical mask plate, a laser stripping device and a method for preparing a flexible display device. An optical mask plate comprises: two first metal plates, the two first metal plates are arranged opposite to each other at intervals in a first direction, and the interval between the two first metal plates in the first direction is adjustable; and two second metal plates, the two second metal plates are arranged opposite to each other at intervals in a second direction, and the interval between the two second metal plates in the second direction is adjustable, and the first direction and the second direction intersect; the two second metal plates are connected to the two first metal plates and surrounded to form a frame structure with a hollow area. The optical mask plate is used for laser stripping, which improves the product yield of the flexible display device. In addition, the optical mask plate has strong applicability and can be applied to the laser stripping of flexible display devices of different sizes, thereby reducing the cost of the laser stripping equipment.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to an optical mask plate, a laser stripping device and a method for preparing a flexible display device. Background Art

[0002] At present, the development of optoelectronic display technology has deeply covered the fields of intelligent equipment, vehicle-mounted display, chemical materials, flexible wearables, aerospace, national defense and military industry. In the development and application of flexible display devices such as OLED and QLED, laser stripping equipment (i.e. LLO equipment) for stripping process has been widely used. The LLO process flow of the entire flexible module is as follows: After the carrier substrate is pre-treated by cleaning, the interface between the flexible substrate formed by the polyimide (i.e. PI) of the flexible display device and the carrier substrate is irradiated with a focused laser beam of a certain energy. The properties of the flexible substrate material at the interface change. The purple laser energy is mainly used to break and eliminate the Si-O bond and van der Waals force at the interface, and the bonding force between the flexible substrate and the carrier substrate is reduced without damaging the flexible display device, so that the flexible display device can be easily separated from the carrier substrate; then separation (Delami), Ash detection and support film (i.e. BP film) attachment and other post-processing processes are carried out.

[0003] Generally speaking, in the development and application fields of flexible display devices, small-sized, medium-sized and large-sized flexible products present different process routes and maturity distinctions. Specifically, for small-sized flexible display device products, such as 5.5 inches, 5.7 inches, and 6.1 inches, the process route mainly adopts the following form: large-sized substrate overall LLO→separation (Delami)→laser cutting→small-sized substrate→binding (Bonding)→BP film attachment. For small-sized flexible display device products, the process route is relatively mature, the technical system is relatively complete, and the overall yield is high. For medium- and large-sized flexible display device products, such as 16.9 inches, 31 inches, and 65 inches, the process route mainly adopts the following form: the entire surface of the flexible substrate is first bonded→the entire surface of the chip is LLO→separation (Delami)→BP film attachment. However, in actual production, it is found that the overall yield of the products obtained by the above-mentioned process of medium- and large-sized flexible display device products is not high. Therefore, the existing technology still needs to be developed. Summary of the invention

[0004] Based on this, it is necessary to provide a laser lift-off device and a method for preparing a flexible display device that can improve the product yield of the flexible display device. Correspondingly, an optical mask is also provided.

[0005] An optical mask, comprising:

[0006] Two first metal plates, the two first metal plates are arranged opposite to each other in a first direction and the distance between the two first metal plates in the first direction is adjustable; and

[0007] Two second metal plates, the two second metal plates are arranged opposite to each other at a distance in a second direction, and the distance between the two second metal plates in the second direction is adjustable;

[0008] wherein the first direction and the second direction intersect;

[0009] The two second metal plates are connected to the two first metal plates and are arranged to form a frame structure with a hollow area.

[0010] In some embodiments, the two first metal plates are arranged in parallel, and the two second metal plates are arranged in parallel; and / or

[0011] The first direction and the second direction are perpendicular to each other.

[0012] In some embodiments, the two first metal plates are respectively located on the same side of the plane formed by the two second metal plates; each of the first metal plates has two overlapping portions respectively overlapping with the two second metal plates.

[0013] In some embodiments, the optical mask further comprises:

[0014] two third metal plates, each of the third metal plates corresponding to each of the second metal plates and arranged opposite to each other in a third direction;

[0015] Wherein, the first direction and the second direction are respectively perpendicular to the third direction;

[0016] The overlapping portion of the first metal plate is located between the second metal plate and the third metal plate.

[0017] In some embodiments, the optical mask further comprises:

[0018] A fixing plate is fixedly connected between the third metal plate and the second metal plate which are spaced apart and arranged opposite to each other, and is located between the respective overlapping portions of the two first metal plates.

[0019] In some of the embodiments, the optical mask further includes four connecting members;

[0020] Among them, each of the first metal plates and each of the second metal plates are provided with a plurality of connecting holes arranged in sequence at intervals along the length extension direction, and each of the connecting members is used to selectively connect a connecting hole in the first metal plate and a connecting hole in the second metal plate, so as to respectively connect the two ends of each of the first metal plates with the two ends of each of the second metal plates to form the frame structure.

[0021] A laser lift-off device, comprising:

[0022] A laser emitting device, wherein the laser emitting device is used to emit laser;

[0023] A laser stripping platform, the laser stripping platform is used to carry the workpiece to be stripped; and

[0024] The optical mask plate described in any of the above items is used to be arranged between the workpiece to be stripped and the laser emitting device, the hollow area of ​​the optical mask plate is used to correspond to the stripping area of ​​the workpiece to be stripped, and the frame structure is used to correspond to the non-stripping area of ​​the workpiece to be stripped.

[0025] In some embodiments, the laser lift-off device further comprises:

[0026] A supporting device, the supporting device is arranged on the laser lift-off platform;

[0027] Among them, the supporting device includes a supporting column and a lifting assembly, the lifting assembly is connected to one end of the supporting column to adjust the height of the supporting column, and the other end of the supporting column has a supporting slot, and the supporting slot is used to cooperate with the optical mask plate to support the optical mask plate.

[0028] In some embodiments, the top of the support column has a support notch, and the support notch is used to cooperate with the end of the first metal plate.

[0029] In some of these embodiments, the laser emitting device includes a laser and a laser beam intercepting module;

[0030] Among them, the laser beam intercepting module is used to intercept the long axis dimension of the laser beam emitted by the laser; the laser beam intercepting module includes a laser sealing box, a first intercepting component and a first movable driving component, the first intercepting component and the first movable driving component are both arranged in the laser sealing box, the laser sealing box is provided with a light emitting slit, and the first movable driving component is connected to the first intercepting component to drive the first intercepting component to move along the length direction of the light emitting slit and cover at least a part of the area of ​​the light emitting slit.

[0031] A method for preparing a flexible display device, using any of the laser lift-off devices described above, the method comprising the following steps:

[0032] Placing a workpiece to be peeled off on the laser peeling platform, wherein the workpiece to be peeled off includes a carrier substrate and a flexible display device disposed on the carrier substrate;

[0033] The optical mask is arranged between the workpiece to be peeled and the laser emitting device, and the spacing between the two first metal plates in the first direction and / or the spacing between the two second metal plates in the second direction are adjusted so that the hollow area of ​​the optical mask corresponds to the peeling area of ​​the flexible display device and the frame structure shields the non-peeling area outside the peeling area of ​​the flexible display device;

[0034] The laser emitting device emits laser light and sequentially scans the interface between the supporting substrate and the flexible display device; and

[0035] The flexible display device is separated from the carrier substrate.

[0036] The size of the frame structure of the optical mask plate is adjustable in the first direction and the second direction, so that the size of the hollow area surrounded by it is adjustable. Therefore, the optical mask plate can be applied to laser lift-off of flexible display devices of different sizes.

[0037] The above-mentioned method for preparing the flexible display device adopts the above-mentioned laser stripping equipment, and by adjusting the spacing between the two first metal plates in the first direction and / or the spacing between the two second metal plates in the second direction, the frame structure of the optical mask plate is used to shield the non-stripping area of ​​the flexible display device, so as to prevent the non-stripping area from being irradiated by laser and causing damage to the electronic components or circuits in the non-stripping area, and the hollow area of ​​the optical mask plate corresponds to the stripping area of ​​the flexible display device, so that the interface between the carrier substrate and the flexible display device is normally subjected to laser scanning, thereby separating the flexible display device from the carrier substrate; thus, the product yield of the flexible display device is improved. In addition, the optical mask plate has strong applicability and can be applied to the laser stripping of flexible display devices of different sizes, thereby reducing the cost of the laser stripping equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic structural diagram of a laser lift-off device according to an embodiment of the present invention;

[0039] Figure 2 for Figure 1 The laser lift-off device shown does not include a laser emitting device and is a schematic structural diagram from another viewing angle;

[0040] Figure 3 for Figure 1A schematic diagram of the structure of an optical mask in a laser lift-off device is shown;

[0041] Figure 4 It is a structural schematic diagram of a flexible display device;

[0042] Figure 5 for Figure 3 A top view of the optical mask shown;

[0043] Figure 6 To contain Figure 3 A top view of a laser lift-off apparatus for an optical mask is shown;

[0044] Figure 7 for Figure 3 A top view of the optical mask in another state;

[0045] Figure 8 To contain Figure 7 A top view of a laser lift-off apparatus for an optical mask is shown;

[0046] Fig. 9 for Figure 1 A schematic structural diagram of a support device on a laser lift-off platform of a laser lift-off device shown;

[0047] Fig.10 for Fig. 9 A schematic structural diagram of the supporting device shown;

[0048] Fig.11 It is a schematic structural diagram of a supporting device on a laser lift-off platform of a laser lift-off device in another embodiment;

[0049] Fig.12 for Figure 1 The schematic diagram of the structure of the laser beam interception module in the laser lift-off equipment shown.

[0050] Description of reference numerals:

[0051] 10: Laser stripping equipment; 100: Laser emitting device;

[0052] 200: Laser lift-off platform; 300: Optical mask;

[0053] 110: laser; 120: laser beam interception module;

[0054] 121: laser sealing box; 1211: light emitting slit;

[0055] 122: a first intercepting component; 123: a first moving driving component;

[0056] 124: a second intercepting component; 125: a second moving driving component;

[0057] 130: laser beam; 310: first metal plate;

[0058] 320: second metal plate; 330: third metal plate;

[0059] 340: fixing plate; 311: connecting hole;

[0060] 01: first direction; 02: second direction;

[0061] 03: third direction; 400: support device;

[0062] 410: support column; 411: support notch;

[0063] 420: lifting rod; 430: lifting drive component;

[0064] 50: flexible display device; 51: peeling area;

[0065] 52: non-stripping area; 60: carrying substrate;

[0066] 511: flexible substrate; 512: display device layer;

[0067] 513: encapsulation layer; 514: barrier layer;

[0068] 515: polarizing layer; 521: circuit board;

[0069] 522: chip; 523: flip chip film;

[0070] 524: Flexible circuit board. DETAILED DESCRIPTION

[0071] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0072] In the description of the present invention, 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", "axial", "radial", "circumferential" and the like 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 invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0073] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0074] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0075] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0076] The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementations.

[0077] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0078] See also Figure 1 The present invention provides a laser lift-off device 10 and an optical mask plate 300 thereof, and a method for preparing a flexible display device 50 using the laser lift-off device 10. The optical mask plate 300 will be described in detail below in conjunction with the laser lift-off device 10 and the method for preparing the flexible display device 50.

[0079] See also Figure 1 and Figure 2 An embodiment of the present invention provides a laser lift-off device 10 , including a laser emitting device 100 , a laser lift-off platform 200 and an optical mask 300 .

[0080] The laser emitting device 100 is used to emit laser.

[0081] The laser stripping platform 200 is used to carry the workpiece to be stripped.

[0082] The optical mask plate 300 is used to be arranged between the workpiece to be peeled and the laser emitting device 100. The hollow area of ​​the optical mask plate 300 is used to correspond to the peeling area of ​​the workpiece to be peeled, and the frame structure of the optical mask plate 300 is arranged corresponding to the non-peeling area of ​​the workpiece to be peeled, so as to shield the non-peeling area of ​​the workpiece to be peeled and prevent the non-peeling area from being irradiated by the laser.

[0083] See also Figure 3 Specifically, the optical mask plate 300 includes two first metal plates 310 and two second metal plates 320. The two first metal plates 310 are arranged opposite to each other in a first direction 01, and the spacing between the two first metal plates 310 in the first direction 01 is adjustable. The two second metal plates 320 are arranged opposite to each other in a second direction 02, and the spacing between the two second metal plates 320 in the second direction 02 is adjustable, and the first direction 01 and the second direction 02 intersect; the two second metal plates 320 are connected to the two first metal plates 310 and are surrounded to form a frame structure with a hollow area.

[0084] Thus, the size of the frame structure of the optical mask plate 300 is adjustable in the first direction 01 and the second direction 02, so that the size of the hollow area surrounded by it is adjustable, and thus the optical mask plate 300 can be applied to laser lift-off of flexible display devices 50 of different sizes.

[0085] The method for preparing the flexible display device 50 using the laser lift-off device 10 of the present invention includes the following steps S10 to S40.

[0086] Step S10: placing the workpiece to be peeled off on the laser peeling platform 200, the workpiece to be peeled off includes a carrier substrate 60 (see Figure 4 ) and a flexible display device 50 (see Figure 4 ).

[0087] Step S20: Place the optical mask plate 300 between the workpiece to be peeled off and the laser emitting device 100, and adjust the spacing between the two first metal plates 310 in the first direction 01 and / or the spacing between the two second metal plates 320 in the second direction 02, so that the hollow area of ​​the optical mask plate 300 corresponds to the peeling area 51 of the flexible display device 50, and the frame structure of the optical mask plate 300 blocks the non-peeling area 52 outside the peeling area 51 of the flexible display device 50.

[0088] Step S30 : the laser emitting device 100 emits laser light and sequentially scans the interface between the supporting substrate 60 and the flexible display device 50 .

[0089] Step S40 : separating the flexible display device 50 from the carrier substrate 60 .

[0090] It is understandable that the separation step of step S40 can be separated by adsorption using an adsorption component, or other separation methods can be used.

[0091] The preparation method of the flexible display device 50 adopts the laser stripping device 10, and uses the frame structure of the optical mask plate 300 to shield the non-stripping area 52 of the flexible display device 50, so as to prevent the non-stripping area 52 from being irradiated by laser and causing damage to the electronic components or circuits in the non-stripping area 52, and the hollow area of ​​the optical mask plate 300 corresponds to the stripping area 51 of the flexible display device 50, so that the interface between the carrier substrate 60 and the flexible display device 50 is normally scanned by laser, so that the flexible display device 50 is separated from the carrier substrate 60; thus, the product yield of the flexible display device 50 is improved. In addition, the optical mask plate 300 has strong applicability and can be applied to the laser stripping of flexible display devices 50 of different sizes, thereby reducing the cost of the laser stripping device 10.

[0092] Understandable, such as Figure 2 As shown, generally, the position of the laser emitting device 100 is kept fixed (that is, the position of the laser beam 130 emitted by the laser emitting device 100 is fixed), and the laser peeling platform 200 is moved along a straight line direction ( Figure 2 The laser stripping platform 200 is moved in the opposite direction of the scanning direction, so that the laser emitting device 100 sequentially scans the interface between the carrier substrate 60 and the flexible display device 50 along the scanning direction.

[0093] See also Figure 4 , wherein the flexible display device 50 includes a peeling area 51 and a non-peeling area 52 outside the peeling area 51. The peeling area 51 is the area corresponding to the flexible substrate 511. Generally, the flexible substrate 511 is a polyimide layer. The peeling area 51 includes an AA area (display area) and a Dummy area (metal wiring area).

[0094] The flexible display device 50 to be peeled is formed on a carrier substrate 60, and when it is placed on the laser peeling platform 200 for laser irradiation, one side of the flexible display device 50 faces downward and the carrier substrate 60 faces upward; the laser beam 130 passes through the carrier substrate 60 and irradiates the interface between the flexible display device 50 and the carrier substrate 60. It can be understood that the flexible display device 50 includes a flexible substrate 511 and a display device layer 512 disposed on the flexible substrate 511.

[0095] In this specific example, the peeling area 51 of the flexible display device 50 to be peeled includes a carrier substrate 60 and a flexible substrate 511, a display device layer 512, an encapsulation layer 513, a barrier layer 514 and a polarizing layer 515 stacked in sequence on the carrier substrate 60. Among them, the display device layer 512 can be an OLED or QLED device layer. The encapsulation layer 513 can be a thin film encapsulation layer. The peeled flexible display device 50 includes a flexible substrate 511, a display device layer 512, an encapsulation layer 513, a barrier layer 514 and a polarizing layer 515 stacked.

[0096] The non-peeling area 52 is located at the periphery of the peeling area 51, and can be specifically arranged around the peeling area 51. The non-peeling area 52 includes a binding area, and the binding area contains a circuit board 521 and a chip 522 (external gate drive IC, chip). By using the frame structure of the optical mask plate 300 to shield the binding area of ​​the flexible display device 50, it is possible to avoid the problem of laser scanning irradiating the binding area during the peeling process and damaging the circuit board 521, chip 522 and other electronic components or circuits in the binding area, thereby improving the yield of the product. In a specific example, the non-peeling area 52 is a binding area.

[0097] In this specific example, the binding area contains a circuit board 521 and a chip 522, and the binding area is bound using a COF process. That is, the chip 521 is first integrated on a flexible circuit board 524 to form a chip-on-film (COP) 523, and then the binding terminals of the flexible circuit board 524 in the chip-on-film 523 are bound to the binding terminals of the circuit board 521. Specifically, the circuit board 521 is a PCB printed circuit board.

[0098] The preparation method of the flexible display device 50 is particularly suitable for the process of first binding and then laser stripping of medium and large-sized flexible display devices 50, avoiding laser irradiation of the binding area in the subsequent laser stripping process, and protecting the circuit board or chip in the binding area.

[0099] The circuit board 521 and the chip 522 of the flexible display device 50 can be distributed on both sides of the long side of the flexible substrate 511 of the flexible display device 50, or can be provided on both sides of the short side. The optical mask plate 300 can be applicable to a flexible display device 50 with COF and PCB on two or four sides, and the width and length of the first metal plate 310 and the second metal plate 320 can be set according to the size of the non-peeling area 52 to be protected. In order to ensure that the optical mask plate 300 effectively protects the non-peeling area 52, the size of the optical mask plate 300 is slightly larger than the corresponding non-peeling area 52. It can be understood that the number of COF and PCB boards contained in the non-peeling area 52 of flexible display devices 50 of different designs is different.

[0100] In a specific example, for a 31-inch flexible display device 50, the size of the peeling area 51 (peeling area 51) of the flexible display device 50 is 697.32mm×405.78mm, the exposed size of the COF and PCB board located on its long side is 49mm, and the exposed size of the COF and PCB board located on its short side is 49mm. Therefore, the length L of the metal sheet used to shield the non-peeling area 52 of the long side in the first metal plate 310 or the second metal plate 320 is: 700mm, the width W is: 50mm~80mm, and the thickness H is 3mm~5mm; the length L of the metal sheet used to shield the non-peeling area 52 of the short side of the substrate is: 410mm, the width W is: 50mm~80mm, and the thickness H is 3mm~5mm. In a specific example, the first metal plate 310 of the optical mask plate 300 is the short side; the second metal plate 320 is the long side.

[0101] like Figure 5 and Figure 6 As shown, the spacing between the two first metal plates 310 of the optical mask plate 300 in the first direction 01 and the spacing between the two second metal plates 320 in the second direction 02 are both adjusted to the maximum size position, for example, suitable for a 31-inch flexible display device 50 .

[0102] like Figure 7 and Figure 8 As shown, the spacing between the two first metal plates 310 of the optical mask plate 300 in the first direction 01 and the spacing between the two second metal plates 320 in the second direction 02 are both adjusted to a position smaller than the maximum size, for example, suitable for a 16-inch flexible display device 50 .

[0103] Please continue reading Figure 3 In some embodiments, two first metal plates 310 are arranged in parallel, and two second metal plates 320 are arranged in parallel. Further, the first direction 01 and the second direction 02 are perpendicular to each other. In other words, the frame structure formed by the optical mask plate 300 is rectangular; further, the hollow area formed is also rectangular.

[0104] Furthermore, the two first metal plates 310 are respectively located on the same side of the plane formed by the two second metal plates 320. Figure 3 In the example, the two first metal plates 310 are both located below the plane formed by the two second metal plates 320; each first metal plate 310 has two overlapping portions respectively overlapping the two second metal plates 320. It can be understood that the overlapping portion is not a fixed area on the second metal plate 320, but refers to an area on the second metal plate 320 that overlaps the second metal plate 320, which changes with the adjustment of the above-mentioned spacing.

[0105] In some embodiments, the optical mask plate 300 further includes four connectors (not shown). Each first metal plate 310 and each second metal plate 320 are sequentially provided with a plurality of connecting holes 311 in the length extension direction, and each connector is used to selectively connect one connecting hole 311 in the first metal plate 310 and one connecting hole 311 in the second metal plate 320, so as to connect the two ends of each first metal plate 310 with the two ends of each second metal plate 320 and form a frame structure. In this way, the four overlaps formed by the two ends of the first metal plate 310 and the two ends of the second metal plate 320 are connected by a connector respectively. In addition, the connector can select different connecting holes 311 as needed to adjust the spacing between the two third metal plates 330 in the second direction 02 and the spacing between the two first metal plates 310 in the first direction 01, so as to meet the needs of flexible display devices 50 of different sizes.

[0106] Further, the connecting member is a screw, and the connecting hole 311 is a screw hole. It is understandable that the position of the connecting hole 311 can be set as required, and the number of the connecting holes 311 can also be set as required, for example, the requirements of the common size of the flexible display device 50 can be considered.

[0107] In one embodiment, the optical mask plate 300 further includes two third metal plates 330, each of which is spaced and arranged opposite to each of the second metal plates 320 in a third direction 03. The first direction 01 and the second direction 02 are respectively perpendicular to the third direction 03. In other words, the plane formed by the intersection of the first direction 01 and the second direction 02 is perpendicular to the third direction 03.

[0108] Furthermore, the orthographic projections of the second metal plate 320 and the third metal plate 330 disposed at intervals on the plane formed by the intersection of the first direction 01 and the second direction 02 overlap with each other.

[0109] Further, the overlapped portion of the first metal plate 310 is located between the second metal plate 320 and the third metal plate 330. Furthermore, the overlapped portion of the first metal plate 310 overlaps the second metal plate 320 and the third metal plate 330 respectively. In other words, one surface of the overlapped portion of the first metal plate 310 overlaps the second metal plate 320, and the other surface overlaps the third metal plate 330 at a relative position.

[0110] In some embodiments, the optical mask plate 300 further includes a fixing plate 340, which is fixedly connected between the third metal plate 330 and the second metal plate 320, which are spaced apart and arranged opposite to each other. The fixing plate 340 is located between the overlapping portions of the two first metal plates 310. In this way, the second metal plate 320, the third metal plate 330 and the fixing plate 340 form an I-shaped plate.

[0111] Furthermore, the thickness of the first metal plate 310 is smaller than the thickness of the fixing plate 340 , so that the first metal plate 310 can move between the third metal plate 330 and the second metal plate 320 , thereby adjusting the above-mentioned distance.

[0112] Furthermore, the distance between the third metal plate 330 and the second metal plate 320 in the third direction 03 is 3 mm to 5 mm. Accordingly, the thickness of the fixing plate 340 in the third direction 03 is the same as the distance between the third metal plate 330 and the second metal plate 320 in the third direction 03.

[0113] It is understood that the third metal plate 330 can be omitted. It is understood that the third metal plate 330 can also be provided with a connection hole 311 corresponding to the second metal plate 320, and the connection hole 311 passes through the second metal plate 320, the first metal plate 310 and the third metal plate 330 at the same time to connect the three. It is understood that in other examples, other metal plates can also be included.

[0114] Furthermore, the materials of the first metal plate 310 , the second metal plate 320 , the third metal plate 330 and / or the fixing plate 340 are independently selected from opaque materials such as stainless steel, magnesium-aluminum alloy or iron-nickel alloy.

[0115] See also Fig. 9 In some embodiments, the laser lift-off device 10 further includes a supporting device 400. The supporting device 400 is disposed on the laser lift-off platform 200 and is used to support the optical mask plate 300 so that there is a gap between the optical mask plate 300 and the workpiece to be lifted off, thereby preventing the optical mask plate 300 from contacting the workpiece to be lifted off and damaging the flexible display device 50.

[0116] See also Fig.10Furthermore, the supporting device 400 includes a supporting column 410 and a lifting assembly (not shown in the figure), the lifting assembly is connected to one end of the supporting column 410 to adjust the height of the supporting column 410, and the other end of the supporting column 410 has a supporting slot 411, and the supporting slot 411 is used to cooperate with the optical mask plate 300 to support the optical mask plate 300.

[0117] Further, the support notch 411 cooperates with the top corner of the optical mask plate 300; in this specific example, the support notch 411 cooperates with the end of the second metal plate 320 located below. Further, there are multiple support devices 400. Accordingly, each support column 410 is used to support each end of the two second metal plates 320, so as to support the optical mask plate 300 at the four top corner positions of the optical mask plate 300.

[0118] Specifically in this example, the support notch 411 is rectangular and is located at a corner of the top of the support column 410. The support notch 411 cooperates with a corner of the second metal plate 320. Furthermore, each support notch 411 of the four support columns 410 cooperates with a corner of the second metal plate 320 facing outward, so as to position and lock the optical mask plate 300. In this way, the support columns 410 are supported at the four corners of the outer frame of the optical mask plate 300, so that the optical mask plate 300 can accurately and stably cover the flexible substrate 511 area of ​​the flexible display device 50.

[0119] In a specific example, the size of the top of the support column 410 is 30mm×30mm, and the cross-sectional size of the support surface in contact with the optical mask plate 300 is 15mm×15mm. The height setting of the support surface of the support column 410 relative to the laser stripping platform 200 takes into account the shielding of the binding area; for example, considering that the thickness of the PCB board is 5mm, the height of the support surface of the support column 410 relative to the laser stripping platform 200 can be set to 8mm-10mm.

[0120] Furthermore, when the support notch 411 cooperates with the optical mask plate 300, the upper surface of the support column 410 is higher than the upper surface of the optical mask plate 300, so that the support column 410 can prevent the device above the optical mask plate 300 (for example, the laser emitting device 100) from further moving toward the optical mask plate 300, thereby squeezing the optical mask plate 300 and protecting the optical mask plate 300. In a specific example, the depth of the support notch 411 on the support column 410 is preferably controlled to be greater than the total thickness of the optical mask plate 300, so that the upper surface of the support column 410 is higher than the upper surface of the optical mask plate 300.

[0121] Furthermore, the lifting assembly includes a lifting rod 420 and a lifting drive component 430. One end of the lifting rod 420 is connected to the support column 410, and the other end is connected to the lifting drive component 430, so that the lifting rod 420 is driven to rise and fall under the action of the lifting drive component 430, and then the supporting column 410 is driven to rise and fall, thereby changing the height position of the optical mask plate 300. Specifically, the lifting drive component 430 can be a servo motor or a driving cylinder.

[0122] Further, the supporting device 400 is disposed on the laser lift-off platform 200 . Specifically, the lifting and lowering driving component 430 is fixedly disposed on the laser lift-off platform 200 .

[0123] Furthermore, according to the requirements of common sizes of the flexible display device 50, a support device 400 can be arranged at a preset position of the laser lift-off platform 200 to meet the requirements of the optical mask plate 300 to adapt to flexible display devices 50 of different sizes, such as Fig.11 As shown. Fig.11 In the specific example shown, the number of the supporting devices 400 is 8, so as to meet the requirement that the optical mask plate 300 can adapt to two flexible display devices 50 of different sizes, thereby achieving good support for the two flexible display devices 50 of different sizes.

[0124] In some embodiments, the workpiece to be peeled is transferred to the laser peeling platform 200 of the laser peeling device 10 after cleaning. The laser scanning parameters are established by the main control software of the laser peeling device 10. When other process parameters are set to constants, the laser energy absorbed at the interface between the PI flexible substrate 511 and the carrier substrate 60 is proportional to the laser energy density value ED. In some examples, the laser energy density ED is set to 130-160 mJ / cm 2 , the laser beam is scanned on the covered area (i.e., the peeling area 51) of the PI flexible substrate 511 of the flexible display device 50. The energy overlap rate (Overlap) is set to 50% to 85%, the scanning frequency is set to 50Hz to 300Hz, the scanning speed (Scan speed) is set to 11.25mm / s to 37.5mm / s, the laser focal plane z value is set to 10.0 to 10.8mm; the number of scans is set to 1. It can be understood that the carrier substrate 60 is generally a glass substrate.

[0125] In a general LLO process, for flexible substrates 511 of different sizes, it is necessary to obtain laser beams 130 with different long-axis sizes, while the short-axis size of the laser beam 130 remains unchanged. Figure 1 and Fig.10As shown, the laser emitting device 100 includes a laser 110 and a laser beam intercepting module 120. The laser beam intercepting module 120 is used to intercept the long axis size of the laser beam 130 emitted by the laser 110, so as to control the opening of the laser beam intercepting module 120, and obtain a laser beam size (Laser beam size) that is the same as the scanning area size. The laser beam size commonly used in the industry is currently 750mm×0.25mm, and the long axis size of the laser beam is 750mm, which usually needs to be intercepted; the short axis size of the laser beam is 0.25mm, which is generally a fixed value.

[0126] Furthermore, if Figure 2 As shown, the long axis direction of the laser beam 130 is the same as the long side direction of the optical mask 300, and the scanning direction of the laser beam 130 is perpendicular to the long axis direction of the laser beam 130 and is the same as the short side direction of the optical mask 300. In other words, the long axis direction of the laser beam 130 is the same as the long axis length of the to-be-stripped area of ​​the workpiece to be stripped.

[0127] Please continue reading Fig.12 Further, the laser beam intercepting module 120 includes a laser sealing box 121, a first intercepting component 122 and a first movable driving component 123. The first intercepting component 122 and the first movable driving component 123 are both arranged in the laser sealing box 121. A light emitting slit 1211 is provided on the laser sealing box 121. The light emitting slit 1211 of the laser sealing box 121 is arranged corresponding to the laser peeling platform 200. The first intercepting component 122 (Laser cutter) is used to block at least part of the light emitting slit 1211. The first movable driving component 123 is connected to the first intercepting component 122 to drive the first intercepting component 122 to move along the length direction of the light emitting slit 1211 and block at least part of the light emitting slit 1211, so as to adjust the effective light emitting length of the light emitting slit 1211 along the length direction, thereby adjusting the major axis size of the laser beam 130.

[0128] Furthermore, the laser beam intercepting module 120 also includes a second intercepting component 124 and a second movable driving component 125, both of which are arranged in the laser sealing box 121, and the second movable driving component 125 is connected to the second intercepting component 124 to drive the second intercepting component 124 to move along the length direction of the light emitting slit 1211. The second intercepting component 124 and the first intercepting component 122 are respectively located at the two ends of the length direction of the light emitting slit 1211 to simultaneously adjust the effective light emitting length of the light slit along the length direction from both ends, thereby adjusting the long axis size of the laser beam 130 to be suitable for flexible display devices 50 of different sizes.

[0129] Specifically, the first moving driving component 123 and / or the second moving driving component 125 are servo motors. In a specific example, the laser beam intercepting module 120 is adjustable in the intercepting range of the long axis size of the laser beam from 0 to 750 mm.

[0130] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0131] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims, and the description and drawings can be used to interpret the content of the claims.

Claims

1. A laser lift-off device, It is characterized in that include: A laser emitting device, wherein the laser emitting device is used to emit laser; A laser stripping platform, wherein the laser stripping platform is used to carry a workpiece to be stripped; and An optical mask plate, comprising two first metal plates and two second metal plates, wherein the two first metal plates are arranged opposite to each other in a first direction and the spacing between the two first metal plates in the first direction is adjustable; The two second metal plates are arranged opposite to each other in a second direction, and the spacing between the two second metal plates in the second direction is adjustable; wherein the first direction and the second direction intersect; the two second metal plates are connected to the two first metal plates and are surrounded to form a frame structure with a hollow area; the optical mask plate is used to be arranged between the workpiece to be stripped and the laser emitting device, the hollow area of ​​the optical mask plate is used to correspond to the stripping area of ​​the workpiece to be stripped, and the frame structure is used to correspond to the non-stripping area of ​​the workpiece to be stripped; The laser emitting device comprises a laser and a laser beam intercepting module; wherein the laser beam intercepting module is used to intercept the long axis dimension of the laser beam emitted by the laser; and the scanning direction of the laser beam is perpendicular to the long axis direction of the laser beam.

2. The laser lift-off device according to claim 1, It is characterized in that The two first metal plates are arranged in parallel, and the two second metal plates are arranged in parallel; and / or The first direction and the second direction are perpendicular to each other.

3. The laser lift-off device according to claim 1, It is characterized in that The two first metal plates are respectively located on the same side of the plane formed by the two second metal plates; each of the first metal plates has two overlapping portions respectively overlapping the two second metal plates.

4. The laser lift-off device according to claim 3, It is characterized in that The optical mask plate further comprises: two third metal plates, each of the third metal plates corresponding to each of the second metal plates and arranged opposite to each other in a third direction; Wherein, the first direction and the second direction are respectively perpendicular to the third direction; The overlapping portion of the first metal plate is located between the second metal plate and the third metal plate.

5. The laser lift-off device according to claim 4, It is characterized in that The optical mask plate further comprises: A fixing plate is fixedly connected between the third metal plate and the second metal plate which are spaced apart and arranged opposite to each other, and is located between the respective overlapping portions of the two first metal plates.

6. The laser lift-off device according to claim 5, It is characterized in that The optical mask plate also includes four connecting members; Among them, each of the first metal plates and each of the second metal plates are provided with a plurality of connecting holes arranged in sequence at intervals along the length extension direction, and each of the connecting members is used to selectively connect a connecting hole in the first metal plate and a connecting hole in the second metal plate, so as to respectively connect the two ends of each of the first metal plates with the two ends of each of the second metal plates to form the frame structure.

7. The laser lift-off device according to any one of claims 1 to 6, It is characterized in that The laser lift-off device also includes: A supporting device, the supporting device is arranged on the laser lift-off platform; Among them, the supporting device includes a supporting column and a lifting assembly, the lifting assembly is connected to one end of the supporting column to adjust the height of the supporting column, and the other end of the supporting column has a supporting slot, and the supporting slot is used to cooperate with the optical mask plate to support the optical mask plate.

8. The laser lift-off device according to any one of claims 1 to 6, It is characterized in that The laser beam intercepting module includes a laser sealing box, a first intercepting component and a first movable driving component. The first intercepting component and the first movable driving component are both arranged in the laser sealing box. A light emitting slit is provided on the laser sealing box. The first movable driving component is connected to the first intercepting component to drive the first intercepting component to move along the length direction of the light emitting slit and cover at least a partial area of ​​the light emitting slit.

9. A method for preparing a flexible display device, It is characterized in that Using the laser lift-off device according to any one of claims 1 to 8, the preparation method comprises the following steps: Placing a workpiece to be peeled off on the laser peeling platform, wherein the workpiece to be peeled off includes a carrier substrate and a flexible display device disposed on the carrier substrate; The optical mask is arranged between the workpiece to be peeled and the laser emitting device, and the spacing between the two first metal plates in the first direction and / or the spacing between the two second metal plates in the second direction are adjusted so that the hollow area of ​​the optical mask corresponds to the peeling area of ​​the flexible display device and the frame structure shields the non-peeling area outside the peeling area of ​​the flexible display device; The laser emitting device emits laser light and sequentially scans the interface between the supporting substrate and the flexible display device; and The flexible display device is separated from the carrier substrate.

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