Display device and manufacturing method thereof

Abstract

The display device includes a display panel, a touch layer, and a flexible printed circuit board. The flexible printed circuit board includes a main flexible printed circuit board and a bridge flexible printed circuit board. The third welding area of ​​the bridge flexible printed circuit board is welded to the first welding area of ​​the main flexible printed circuit board. The fourth welding area of ​​the bridge flexible printed circuit board is welded to the second welding area of ​​the main flexible printed circuit board. Each first touch connecting line of the main flexible printed circuit board has one end electrically connected to the touch chip and the other end electrically connected to the first touch lead line of the touch layer. Each second touch connecting line of the main flexible printed circuit board has one end electrically connected to the pad of the second welding area and the other end electrically connected to the second touch lead line of the touch layer. Each third touch connecting line of the main flexible printed circuit board has one end electrically connected to the pad of the first welding area and the other end electrically connected to the touch chip. Each touch converting line of the bridge flexible printed circuit board has one end electrically connected to the pad of the third welding area and the other end electrically connected to the pad of the fourth welding area.

Description

[Technical field]

[0001] The present disclosure relates to the field of display technology, and more particularly to a display device and a manufacturing method thereof. [Background technology]

[0002] With the development of display technology, display devices with touch technology FMLOC (Flexible Multi-Layer On Cell) structure have appeared on the market, and FMLOC display devices include a display panel, a touch layer on the display panel, and a flexible printed circuit (FPC). The flexible printed circuit is electrically connected to the display panel to realize the transmission of display signals to the display panel and the transmission of touch signals to the touch layer, thereby realizing image display and touch point positioning. Summary of the Invention [Means for solving the problem]

[0003] In one embodiment, a display device is provided. The display device includes a display panel, a touch layer provided on a light output surface of the display panel, and a flexible printed circuit board bonded to the display panel. The touch layer includes a plurality of first touch lead wires and a plurality of second touch lead wires. The flexible printed circuit board includes a main flexible printed circuit board and a bridge flexible printed circuit board.

[0004] The main flexible printed circuit board includes a first substrate, a plurality of pads, a touch chip, a plurality of first touch connecting lines, a plurality of second touch connecting lines, and a plurality of third touch connecting lines. The first substrate has a first welding area, a second welding area, and a bonding area. The bonding area is an area of ​​the first substrate bonded to the display panel. The plurality of pads are provided in the first welding area and the second welding area. The touch chip is provided on the first substrate, and a minimum distance between the touch chip and the first welding area is smaller than a minimum distance between the touch chip and the second welding area. The plurality of first touch connecting lines are provided on the first substrate, and each of the first touch connecting lines has one end electrically connected to the touch chip and the other end electrically connected to the touch layer. Among the plurality of first touch leads The second touch connection lines are provided on the first substrate, and each of the second touch connection lines has one end connected to the second welding area. handle One end is electrically connected to one pad on the touch layer, and the other end is electrically connected to the Among the plurality of second touch leads The third touch connection lines are provided on the first substrate, and each of the third touch connection lines has one end connected to the first welding area. handle One end is electrically connected to the pad, and the other end is electrically connected to the touch chip.

[0005] The bridge flexible printed circuit board includes a second substrate, a plurality of pads, and a plurality of touch conversion lines, the second substrate having a third welding area and a fourth welding area, the plurality of pads being provided in the third welding area and the fourth welding area, one pad of the third welding area and one pad of the first welding area being provided in the fourth welding area, handle One pad of the fourth welding area and one pad of the second welding area are welded together. handle The touch conversion lines are disposed on the second substrate, and one end of each of the touch conversion lines is welded to the third welding area. handle one end electrically connected to a pad in the fourth welding area and the other end electrically connected to a corresponding pad in the fourth welding area; Either oneThe maximum radial size of the pad is 1.0 mm or less.

[0006] In some embodiments, the bridge flexible printed circuit board further includes at least one shield transfer line disposed on the second substrate, each shield transfer line having one end adjacent to the third welding area. handle one end of the fourth welded area is electrically connected to the other pad of the fourth welded area. handle It is electrically connected to one pad.

[0007] In some embodiments, the bridge flexible printed circuit board includes a plurality of the shielding conversion lines. The plurality of the shielding conversion lines includes at least two edge shielding conversion lines located on the outermost sides. Both ends of one edge shield conversion line and both ends of the other edge shield conversion line are connected in sequence. The touch conversion lines are connected to each other to form a ring. The touch conversion lines are all disposed inside the ring.

[0008] In some embodiments, the third weld area and the fourth weld area To teeth, both M row pad is established. , where M≧2. Of the two edge shield conversion lines, The above Both ends of one edge shield conversion line are The third welding area The side of the first pad away from the last pad and on a side of the fourth welding area away from the last row of pads in the first row of pads, electrically connected to the two most distant pads among the first row of pads in the third welding area and the first row of pads in the fourth welding area; The above The other end of the edge shielded conversion line is The third welding area The side of the last pad away from the first pad and on a side of the pads in the last row of the fourth welding region away from the pads in the first row, The pads are electrically connected to the two pads that are furthest apart from each other among the pads in the last row of the third welding region and the pads in the last row of the fourth welding region. The pads in the first row of pads in the third welding area that are electrically connected to the one edge shield conversion line are electrically connected to the pads in the last row of pads in the third welding area that are electrically connected to the other edge shield conversion line; the pads in the first row of pads in the fourth welding area that are electrically connected to the one edge shield conversion line are electrically connected to the pads in the last row of pads in the fourth welding area that are electrically connected to the other edge shield conversion line.

[0009] In some embodiments, the third welding area and the fourth welding area are provided on opposite ends of the second substrate, and an orthogonal projection of the second substrate on the main flexible printed circuit board is not a centrosymmetric figure.

[0010] In some embodiments, the third weld region and The fourth welding area To teeth ,both M row pad is established. , where M≧2. At least 2M pads are distributed between the two outermost conversion lines among the plurality of conversion lines on the second substrate. and the plurality of transducer lines includes the plurality of touch transducer lines and the at least one shield transducer line. .

[0011] In some embodiments And before The first welding area and the second welding area are arranged side by side along a first direction that is substantially parallel to an extension direction of a side of the main flexible printed circuit board that is closer to the display panel.

[0012] In some embodiments, the pads in the third welding area and the pads in the fourth welding area are both arranged in multiple rows; At least one row of pads in the third welding region includes a plurality of pads arranged along the first direction, and at least one row of pads in the fourth welding region includes a plurality of pads arranged along the first direction. The at least one row of pads includes a plurality of pads arranged along the first direction, and at least one conversion line of the plurality of conversion lines on the second substrate passes through an area of ​​the third welding area and the fourth welding area other than an area between the pads in the first row and the pads in the last row, and is electrically connected to a corresponding pad. The plurality of transducer lines includes the plurality of touch transducer lines and the at least one shield transducer line.

[0013] In some embodiments, the pads in two adjacent rows are offset from each other along a second direction, the second direction being substantially perpendicular to the first direction.

[0014] In some embodiments, the second substrate includes a transition wiring region and connection sector regions located on opposite ends of the transition wiring region. The transition wiring region and the connection sector region are located between the third welding region and the fourth welding region. The above Each of the plurality of transducer lines including the plurality of touch transducer lines and the at least one shield transducer lineThe conversion line includes a transition segment and a connection segment located at opposite ends of the transition segment, the transition segment extending along the first direction and disposed in the transition wiring region, and the connection segment disposed in the connection sector region, wherein a minimum width of the connection sector region in the second direction is equal to or greater than a width of the transition wiring region in the second direction, and the second direction is substantially perpendicular to the first direction.

[0015] In some embodiments, the width of the transition wiring region in the second direction is smaller than the maximum width of the third weld region in the second direction; and / or the width of the transition wiring region in the second direction is smaller than the maximum width of the fourth weld region in the second direction. Part , the maximum width in the second direction but , greater than the maximum width in the second direction of the third welded area; and / or of a connection sector area close to the fourth welded area. Part , the maximum width in the second direction but , which is greater than the maximum width of the fourth welded region in the second direction.

[0016] In some embodiments, the outer contour of the pad is generally circular.

[0017] In some embodiments, the diameter of the pad ranges from 0.25mm to 0.35mm.

[0018] In some embodiments, the pad on the second substrate is a via pad. The second substrate has a plurality of vias, each of which corresponds to one via pad. The via pad includes two solder lugs and a conductive connection layer. The two solder lugs are provided on a surface of the second substrate close to the main flexible printed circuit board and a surface of the second substrate away from the main flexible printed circuit board, respectively. A via corresponding to the via pad passes through the second substrate between the two solder lugs of the via pad and the two solder lugs. The conductive connection layer includes: The via padIt covers the sidewalls of the via and has two ends electrically connected to the two solder lugs, respectively.

[0019] In some embodiments, the outer contour of the orthogonal projection of the via pad on the second substrate is substantially circular.

[0020] In some embodiments, the diameter of the outer contour of the via pad is in the range of 0.25 mm to 0.35 mm.

[0021] In some embodiments, the inner contour of the orthogonal projection of the via pad on the second substrate is substantially circular or X-shaped.

[0022] In some embodiments, when the inner contour of the via pad in the orthogonal projection on the second substrate is circular, the diameter of the inner contour is in the range of 0.05 mm to 0.15 mm.When the inner contour of the via pad in the orthogonal projection on the second substrate is X-shaped, the diameter of the circumscribed circle corresponding to the inner contour is in the range of 0.05 mm to 0.2 mm.

[0023] In some embodiments, the main flexible printed circuit board further includes a first metal pattern covering pads on the first substrate, the first metal pattern being arranged to prevent the pads on the first substrate from being oxidized; and / or the bridge flexible printed circuit board further includes a second metal pattern covering pads on the second substrate, the second metal pattern being arranged to prevent the pads on the second substrate from being oxidized.

[0024] In some embodiments, when the main flexible printed circuit board includes a first metal pattern, the material of the first metal pattern includes a combination of one or two of gold and nickel, and when the bridge flexible printed circuit board includes a second metal pattern, the material of the second metal pattern includes a combination of one or two of gold and nickel.

[0025] In some embodiments, the main flexible printed circuit board further includes a first green oil layer and a first resin layer. The first green oil layer covers at least a first region of the first substrate, the first region being a region of the first welding region and the second welding region other than a region where a pad is provided. The first resin layer covers a region of the first substrate other than the first welding region and the second welding region. The bridge flexible printed circuit board further includes a second green oil layer and a second resin layer. The second green oil layer covers at least a second region of the second substrate, the second region being a region of the third welding region and the fourth welding region other than a region where a pad is provided. The second resin layer covers a region of the second substrate other than the third welding region and the fourth welding region.

[0026] In some embodiments, the first substrate has an element region. The main flexible printed circuit board further includes at least one element and a third green oil layer. The at least one element is provided on a side of the first substrate close to the bridge flexible printed circuit board and located in the element region of the first substrate. The at least one element includes the touch chip. The third green oil layer covers an area of ​​the element region other than the area where the at least one element is provided.

[0027] In some embodiments, the main flexible printed circuit board further includes a support provided on a side of the first substrate away from the bridge flexible printed circuit board, and the element region is within the range of an orthogonal projection of the support on the first substrate.

[0028] In some embodiments, there is a gap between a boundary of the orthogonal projection of the support on the first substrate and a boundary of the element region, the gap being 0.5 mm or more.

[0029] In some embodiments, the main flexible printed circuit board further includes a plurality of first bonding pins and a plurality of second bonding pins, the plurality of first bonding pins are provided in the bonding area, and at least one first bonding pin is arranged to electrically connect the first touch connection line to a corresponding first touch lead line in a touch layer of the display device, the plurality of second bonding pins are provided in the bonding area, and at least one second bonding pin is arranged to electrically connect the second touch connection line to a corresponding second touch lead line in the touch layer.

[0030] In some embodiments, the range of the maximum size L1 of the main flexible printed circuit board along the first direction is 55.25 mm≦L1≦55.55 mm. The first direction is approximately parallel to an extension direction of the side edge of the main flexible printed circuit board close to the display panel. The bonding region is strip-shaped and extends along the first direction. The first bonding pins and the second bonding pins are arranged side by side along the first direction. The first bonding pin and the second bonding pin that are furthest apart on the main flexible printed circuit board along the first direction are Distance away L The range of L2 is 53.55 mm≦L2≦53.85 mm. L The range of L3 is 1.2 mm≦L3≦1.6 mm. The second direction is approximately perpendicular to the first direction.

[0031] In some embodiments, the number of first touch leads included in the touch layer is the same as the number of first touch connecting lines included in the main flexible printed circuit board, and the number of second touch leads included in the touch layer is the same as the number of second touch connecting lines and the number of third touch connecting lines included in the main flexible printed circuit board.

[0032] In some embodiments, the main flexible printed circuit board further includes a plurality of data signal control lines provided on the first substrate. The display panel has a display area and a peripheral area located on at least one side of the display area. The display panel includes a plurality of data lines and a driving chip. The driving chip is provided in the peripheral area and is electrically connected to the plurality of data signal control lines and the plurality of data lines. The driving chip is arranged to process signals on the plurality of data signal control lines and output them to the plurality of data lines.

[0033] In some embodiments, the number of data signal control lines included in the main flexible printed circuit board is less than the number of data lines included in the display panel, and the line width of the data signal control lines is wider than the line width of the data lines.

[0034] In some embodiments, the main flexible printed circuit board further includes a first bonding pin and a second bonding pin. The display panel further includes a plurality of first bonding pads and a plurality of second bonding pads. The first bonding pad is: handle one of the first bonding pins; and handle A first bonding pad is electrically connected to the first touch lead. handle one said second bonding pin; and handle Electrically connected to one second touch lead.

[0035] In some embodiments, a thickness of the first bonding pad and a thickness of the second bonding pad are both smaller than the distance between a surface of the touch layer closer to the display panel and a surface of the display panel away from the touch layer.

[0036] In another aspect, a display device is provided. The display device includes a display panel, a touch layer provided on a light exit surface of the display panel, and a flexible printed circuit board bonded to the display panel. The display panel has a display area and a peripheral area located on at least one side of the display area, and a bonding part including a plurality of first bonding pads and a plurality of second bonding pads is provided in the peripheral area. The touch layer includes a plurality of first touch lead wires and a plurality of second touch lead wires, and one first touch lead wire is The corresponding one of the first bonding pads a second touch lead electrically connected to the first bonding pad; The corresponding one of the second bonding pads Electrically connected to one of the second bonding pads.

[0037] The flexible printed circuit board includes a main flexible printed circuit board and a bridge flexible printed circuit board. The main flexible printed circuit board includes a first substrate, a plurality of pads, a touch chip, a plurality of first touch connecting lines, a plurality of second touch connecting lines, and a plurality of third touch connecting lines. The first substrate has a first welding area, a second welding area, and a bonding area. A plurality of first bonding pins and a plurality of second bonding pins are provided in the bonding area. Each first bonding pin is ,handle A first bonding pad is electrically connected to a second bonding pin. ,handle The first bonding pin and the second bonding pad are electrically connected to each other. The pads are provided in the first welding area and the second welding area. The touch chip is provided on the first substrate, and a minimum distance between the touch chip and the first welding area is smaller than a minimum distance between the touch chip and the second welding area. The first touch connection lines are provided on the first substrate, and each of the first touch connection lines has one end electrically connected to the touch chip and the other end electrically connected to the first bonding pin and the first bonding pad via the first bonding pad. handle The second touch connection lines are provided on the first substrate, and each of the second touch connection lines has one end connected to the second welding area. handleThe other end is electrically connected to the second bonding pin and the second bonding pad. handle The third touch connection lines are provided on the first substrate, and each of the third touch connection lines has one end connected to the first welding area. handle One end is electrically connected to the pad, and the other end is electrically connected to the touch chip.

[0038] The bridge flexible printed circuit board includes a second substrate, a plurality of pads, and a plurality of touch conversion lines. The second substrate has a third welding area and a fourth welding area. The plurality of pads are provided in the third welding area and the fourth welding area, and one pad in the third welding area and one pad in the first welding area are provided in the fourth welding area. handle The touch conversion lines are provided on the second substrate, and one end of each of the touch conversion lines is welded to the corresponding pad of the third welding area, and one end of each of the touch conversion lines is welded to the corresponding pad of the fourth welding area. handle one end of the fourth welded area is electrically connected to the other pad of the fourth welded area. handle It is electrically connected to one pad.

[0039] Either one The maximum radial size of the pad is 1.0 mm or less.

[0040] The third welding area and The fourth welding area To teeth both M row pad is established. , where M≧2. At least 2M pads are distributed between two outermost touch conversion lines among the plurality of touch conversion lines.

[0041] The pads in the first welding area, the second welding area, the third welding area, and the fourth welding area are all arranged in a plurality of rows; At least one row of pads of the third welding area includes a plurality of pads, and at least one row of pads of the fourth welding area includes a plurality of pads. At least one row of pads includes a plurality of pads. Two adjacent rows of pads include: Second The electrodes are offset from each other along the direction.The second direction is substantially perpendicular to the extending direction of the side of the main flexible printed circuit board that is closer to the display panel.

[0042] The pads on the bridge flexible printed circuit board are via pads. The second substrate has a plurality of vias, each of which corresponds to one via pad. The via pad includes two solder lugs and a conductive connection layer. The two solder lugs are provided on a surface of the second substrate close to the main flexible printed circuit board and a surface of the second substrate away from the main flexible printed circuit board, respectively. A via corresponding to the via pad penetrates the second substrate between the two solder lugs of the via pad and through the two solder lugs. The conductive connection layer includes: The via pad It covers the sidewalls of the via and has two ends electrically connected to the two solder lugs, respectively.

[0043] In some embodiments, the flexible printed circuit board includes a plurality of data signal control lines. The display panel includes a plurality of data lines and a driver chip. The driver chip is disposed in the peripheral region and electrically connected to the plurality of data signal control lines and the plurality of data lines. The driver chip is disposed to process signals on the plurality of data signal control lines and output them to the plurality of data lines. The number of the data signal control lines is less than the number of the data lines, and the line width of the data signal control lines is wider than the line width of the data lines.

[0044] In some embodiments, the number of first touch leads included in the touch layer is the same as the number of first touch connecting lines included in the main flexible printed circuit board, and the number of second touch leads included in the touch layer is the same as the number of second touch connecting lines and the number of third touch connecting lines included in the main flexible printed circuit board.

[0045] In some embodiments, the range of the maximum size L1 of the main flexible printed circuit board along the first direction is 55.25 mm≦L1≦55.55 mm. The first direction is approximately parallel to an extension direction of the side edge of the main flexible printed circuit board close to the display panel. The bonding region is strip-shaped and extends along the first direction. The first bonding pins and the second bonding pins are arranged side by side along the first direction. The first bonding pin and the second bonding pin that are furthest apart on the main flexible printed circuit board along the first direction are Distance away L The range of L2 is 53.55 mm≦L2≦53.85 mm. L 3. The range is 1.2mm≦L3≦1.6mm 。

[0046] In yet another aspect, a method for manufacturing a display device is provided, the method for manufacturing the display device includes forming a main flexible printed circuit board including a first substrate, a plurality of pads provided in a first welding area and a second welding area of ​​the first substrate, a touch chip provided on the first substrate, a plurality of first touch connecting lines, a plurality of second touch connecting lines, a plurality of third touch connecting lines, a plurality of first bonding pins, and a plurality of second bonding pins, wherein one end of each of the first touch connecting lines is electrically connected to the touch chip and the other end of the first touch connecting line is electrically connected to the touch chip. handle Each of the second touch connection lines is electrically connected to one of the first bonding pins, and one end of each of the second touch connection lines is disposed in the second welding area. handle Electrically connected to one pad and the other end handle Each of the third touch connection lines is electrically connected to one of the second bonding pins, and one end of each of the third touch connection lines is in contact with the first welding area. handle One end is electrically connected to the pad, and the other end is electrically connected to the touch chip;

[0047] forming a bridge flexible printed circuit board including a second substrate, a plurality of pads provided in a third welding area and a fourth welding area of ​​the second substrate, and a plurality of touch conversion lines, wherein one end of each of the touch conversion lines is disposed in the third welding area and a fourth welding area of ​​the second substrate; handle one end of the fourth welded area is electrically connected to the other pad of the fourth welded area. handle Electrically connected to one pad;

[0048] welding a plurality of pads in the first welding area to a plurality of pads in the third welding area in correspondence with each other, and welding a plurality of pads in the second welding area to a plurality of pads in the fourth welding area in correspondence with each other, to obtain a flexible printed circuit board;

[0049] forming a display panel and a touch layer, where the touch layer is located on a light-emitting surface of the display panel, the display panel includes a plurality of first bonding pads and a plurality of second bonding pads, the touch layer includes a plurality of first touch leads and a plurality of second touch leads, each of the first touch leads being connected to a light-emitting surface of the display panel; handle Each of the second touch leads is electrically connected to one of the first bonding pads of the display panel. handle electrically connected to one second bonding pad;

[0050] and bonding a display panel provided with a touch layer to the flexible printed circuit board so as to electrically connect the plurality of first bonding pads to the plurality of first bonding pins in correspondence with each other, and to electrically connect the plurality of second bonding pads to the plurality of second bonding pins in correspondence with each other.

[0051] In some embodiments, forming the main flexible printed circuit board includes forming a first conductive layer on a surface of the first substrate and patterning the first conductive layer to form a plurality of pads in the first welding area and the second welding area, and forming a first metal pattern on a surface of the plurality of pads, the first metal pattern being arranged to prevent the plurality of pads from being oxidized.

[0052] The formation of the bridge flexible printed circuit board includes: Pair forming a second conductive layer on opposing surfaces of a second substrate and patterning the second conductive layer to form a plurality of solder lugs; forming a second metal pattern on the surfaces of the plurality of solder lugs on the opposing surfaces of the second substrate, the second metal pattern being arranged to protect the plurality of solder lugs from oxidation; Each forming a via penetrating through the second substrate between the two solder lugs at the positions of the two solder lugs facing each other along a thickness direction of the second substrate; forming a conductive connection layer on a side wall of the via, where both ends of the conductive connection layer are electrically connected to the two solder lugs, respectively, the conductive connection layer including a conductive layer and a metal layer sequentially stacked, the metal layer being arranged to prevent the conductive layer from being oxidized;

[0053] In some embodiments, the method further comprises: The first substrate The first welding area, the second welding area and element area , and the second substrate The third welding area, the fourth welding area In the region applying green oil; removing the green oil from the first welding region, the second welding region, the third welding region, and the fourth welding region where the pads are provided, so as to expose the pads; and removing the green oil from the element region where the elements are provided, so as to expose each element; The first substrate and the second substrateThe method further includes applying a resin material to an area other than the first welded area, the second welded area, the third welded area, the fourth welded area, and the element area.

[0054] In some embodiments, the step of welding the plurality of pads in the first welding area to the plurality of pads in the third welding area and welding the plurality of pads in the second welding area to the plurality of pads in the fourth welding area to obtain a flexible printed circuit board includes: applying solder paste to the plurality of pads in the first welding area and the second welding area; aligning and attaching the main flexible printed circuit board and the bridge flexible printed circuit board, attaching the plurality of pads in the first welding area to the plurality of pads in the third welding area to the plurality of pads in the third welding area to the plurality of pads in the second welding area to the plurality of pads in the fourth welding area to the plurality of pads in the second welding area; and heating the attached main flexible printed circuit board and the bridge flexible printed circuit board to melt the solder paste.

[0055] In some embodiments, the step of aligning and attaching the main flexible printed circuit board and the bridge flexible printed circuit board includes: No. 1 A first image including an alignment mark and a bridge flexible printed circuit board Second and processing the first and second images to obtain a first image of the main flexible printed circuit board including an alignment mark. The above The coordinates of the first alignment mark and the bridge flexible printed circuit board The above obtaining coordinates of a second alignment mark; and aligning the main flexible printed circuit board and the bridge flexible printed circuit board. The above The coordinates of the first alignment mark and The aboveControlling a robot arm to move the bridge flexible printed circuit board and / or the main flexible printed circuit board according to the coordinates of the second alignment mark; acquiring a third image including the alignment mark of the aligned main flexible printed circuit board and a fourth image including the alignment mark of the aligned bridge flexible printed circuit board; detecting whether the relative position of the aligned main flexible printed circuit board and the bridge flexible printed circuit board is within a preset error range; and detecting whether the relative position of the aligned main flexible printed circuit board and the bridge flexible printed circuit board is within a preset error range. In response to detecting that the main flexible printed circuit board and the bridge flexible printed circuit board are attached to each other by an adhesive layer; In response to detecting that the relative position of the main flexible printed circuit board and the bridge flexible printed circuit board is not within a preset error range, ,continuation ,before The relative positions of the main flexible printed circuit board and the bridge flexible printed circuit board are , until the relative positions of the two are within a preset error range. tone Adjust This includes: [Brief description of the drawings]

[0056] In order to more clearly describe the technical solutions in the embodiments of the present disclosure, the following briefly describes the necessary drawings used in some embodiments of the present disclosure. The drawings in the following description are only drawings of some embodiments of the present disclosure, and it is obvious for a person skilled in the art to obtain other drawings based on these drawings. Furthermore, the drawings in the following description can be regarded as schematic diagrams, and do not limit the actual dimensions of the products, the actual processes of the methods, the actual timing of the signals, etc., according to the embodiments of the present disclosure. [Figure 1] 1 is a structural diagram of a display device according to some embodiments; [Diagram 2] FIG. 2 is an exploded view of a touch display module of a display device according to some embodiments. [Figure 3A] 3 is a cross-sectional view taken along the line II' of the touch display module shown in FIG. 2 when the display panel is an electroluminescence display panel; [Figure 3B]3 is another cross-sectional view taken along the II' direction when the display panel of the touch display module shown in FIG. 2 is an electroluminescence display panel. FIG. [Figure 3C] 3 is a cross-sectional view taken along line II' in the case where the display panel of the touch display module shown in FIG. 2 is a liquid crystal display panel. [Figure 3D] 3 is another cross-sectional view taken along the line II' in the case where the display panel of the touch display module shown in FIG. 2 is a liquid crystal display panel. [Figure 4] 1A to 1C are structural diagrams of bonding between a flexible printed circuit board and a display panel according to some embodiments. [Diagram 5] 1 is a structural diagram of a main flexible printed circuit board according to some embodiments. [Figure 6] 1 is a structural diagram of a bridge flexible printed circuit board according to some embodiments. [Figure 7] 4A to 4C are enlarged views of a portion of a display panel to be bonded to a main flexible printed circuit board in accordance with some embodiments. [Figure 8] FIG. 13 is a structural diagram of the side of the main flexible printed circuit board away from the bridge flexible printed circuit board in some embodiments. [Figure 9] 1 is a structural diagram of a support according to some embodiments. [Figure 10] 10 is a cross-sectional view of the support body in FIG. 9 taken along the line HH'. [Figure 11] FIG. 13 is a structural diagram of another bridge flexible printed circuit board according to some embodiments. [Figure 12] FIG. 13 is a structural diagram of yet another bridge flexible printed circuit board according to some embodiments. [Figure 13] FIG. 2 is a film layer structure diagram of a main flexible printed circuit board or a bridge flexible printed circuit board in some embodiments. [Figure 14] FIG. 2 is another film layer structure diagram of a main flexible printed circuit board or a bridge flexible printed circuit board according to some embodiments. [Figure 15]FIG. 13 is yet another film layer structure diagram of a main flexible printed circuit board or a bridge flexible printed circuit board according to some embodiments. [Figure 16] FIG. 13 is yet another film layer structure diagram of a main flexible printed circuit board or a bridge flexible printed circuit board according to some embodiments. [Figure 17] FIG. 2 is a film layer structure diagram of a bridge flexible printed circuit board according to some embodiments. [Figure 18] FIG. 2 is another film layer structure diagram of a bridge flexible printed circuit board according to some embodiments. [Figure 19] FIG. 13 is a structural diagram of the side of the main flexible printed circuit board close to the bridge flexible printed circuit board in some embodiments. [Figure 20] FIG. 13 is a structural diagram of the side of the main flexible printed circuit board away from the bridge flexible printed circuit board in some embodiments. [Figure 21] FIG. 21 is an enlarged view of the bonding area in FIG. 20 according to some embodiments. [Figure 22] 1 is a structural diagram of a pad shape according to some embodiments. [Diagram 23] 11A-11C are schematic diagrams of alternative pad configurations according to some embodiments. [Figure 24] 11A-11C are schematic diagrams of yet another pad shape according to some embodiments. [Diagram 25] FIG. 2 is a close-up view of a welded area (which may be either a first welded area, a second welded area, a third welded area, or a fourth welded area) according to some embodiments. [Figure 26A] A structural diagram of a bridge flexible printed circuit board when the inner contour shape of the via pad is circular in some embodiments. [Figure 26B] FIG. 1 illustrates a close-up view of a via pad having an X-shaped inner contour, according to some embodiments. [Figure 27] 26B is a cross-sectional view of the via pad in FIG. 26A taken along the line AA'. [Figure 28]11A and 11B are structural diagrams of a bridge flexible printed circuit board in accordance with some embodiments, in which green oil is applied to areas of the third and fourth welding areas other than the areas where pads are provided. [Figure 29A] FIG. 29 is an enlarged view of a third welding region in FIG. 28. [Figure 29B] FIG. 29 is an enlarged view of a fourth welding area in FIG. 28. [Figure 30A] FIG. 29B is an X-ray view of FIG. 29A. [Figure 30B] This is an X-ray diagram of Figure 29B. [Diagram 31] 1 is a flowchart of a method for manufacturing a display device according to some embodiments. [Diagram 32] 1 is a flowchart of another method for manufacturing a display device according to some embodiments. [Diagram 33] 10 is a flowchart of yet another method for manufacturing a display device according to some embodiments. [Diagram 34] 10 is a flowchart of yet another method for manufacturing a display device according to some embodiments. [Diagram 35] 10 is a flowchart of yet another method for manufacturing a display device according to some embodiments. [Diagram 36] 10A-10C are diagrams showing the structure of a main flexible printed circuit board when solder paste is applied to the pads in the first and second welding areas in some embodiments. [Figure 37] 10A-10C are cross-sectional views of some pads with solder paste applied to the pads in the first and second welding areas of the main flexible printed circuit board according to some embodiments. [Figure 38] 13A-13C are schematic diagrams of solder paste thickness at various positions after a main flexible printed circuit board and a bridge flexible printed circuit board are welded together according to some embodiments. [Figure 39] 10 is a flowchart of yet another method for manufacturing a display device according to some embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0057] The following clearly and completely describes the technical solutions of some embodiments of the present disclosure with reference to the drawings, but it is clear that the described embodiments are only some of the embodiments of the present disclosure, and are not all of the embodiments. All other embodiments obtained by those skilled in the art based on some embodiments of the present disclosure all belong to the protection scope of the present disclosure.

[0058] In the present specification and claims, the term "comprise" and other forms thereof, such as the third person singular form "comprises" and the present participle form "comprising" should be interpreted in an open, inclusive sense, i.e., "including but not limited to," unless the context requires otherwise. In the description of this specification, the terms "one embodiment," "some embodiments," "exemplary embodiments," "examples," "specific examples," "some examples," and the like are intended to indicate that a particular feature, structure, material, or characteristic associated with the embodiment or example is included in at least one embodiment or example of the present disclosure. General expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, a particular feature, structure, material, or characteristic described may be included in any one or more embodiments or examples in any suitable manner.

[0059] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to express or imply a relative importance or number of technical features shown. Thus, a feature qualified with "first" or "second" may explicitly or implicitly include one or more of the feature. In the description of the embodiments of the present disclosure, "plurality" means two or more, unless otherwise specified.

[0060] When describing some embodiments, the term "connected" and expressions derived therefrom may be used. For example, when describing some embodiments, the term "connected" may be used to indicate that two or more components have direct physical or electrical contact with each other. The embodiments disclosed herein are not necessarily limited to the contents of this specification.

[0061] "At least one of A, B, and C" has the same meaning as "at least one of A, B, or C," and all of them include A only, B only, C only, a combination of A and B, a combination of A and C, a combination of B and C, and a combination of A, B, and C.

[0062] "A and / or B" includes the three combinations of A only, B only, and a combination of A and B.

[0063] As used herein, "applied to" or "configured to" is intended to be open and inclusive language that does not exclude devices that are adapted or configured to perform additional tasks or steps.

[0064] Additionally, the use of "based on" is meant to be open and inclusive, as a process, step, calculation, or other action performed "based on" one or more of the conditions or values ​​may, in fact, be based on additional conditions or beyond the values.

[0065] As used herein, "about," "approximately," or "approximate" includes the stated value and the average within an acceptable range of deviation of the particular value, where the acceptable range of deviation is determined taking into account the measurement contemplated by one of ordinary skill in the art and the error associated with the measurement of the particular quantity (i.e., limitations of the measurement system).

[0066] Exemplary embodiments are described herein with reference to cross-sectional and / or plan views that are idealized exemplary drawings. In the drawings, thicknesses of layers and regions are exaggerated for clarity. Thus, variations in shape relative to the drawings due to, for example, manufacturing techniques and / or tolerances can be expected. Thus, the exemplary embodiments should not be construed as limited to the shapes of regions illustrated herein, but include deviations in shape due to manufacturing and the like. For example, an etched region shown as a rectangle will typically have curved features. Thus, the regions shown in the drawings are exemplary in nature, and their shapes are not intended to represent the actual shape of a region of a device, and are not intended to limit the scope of the exemplary embodiments.

[0067] 1, the display device 100 is a device or apparatus that visualizes and displays electronic information. In some embodiments, the display device 100 includes at least one touch display panel 3 (also referred to as a touch display screen, touch panel, touch screen, etc.) that can be operated and controlled by clicking a screen with a finger (which may be a stylus or other tool). Exemplarily, the display device 100 can be any product or part having a display function, such as a smartphone, a tablet computer, a television, a display, a notebook computer, and other wearable electronic devices (e.g., a wristwatch).

[0068] Here, the type of the display device 100 is not limited, and may be a liquid crystal display device (abbreviated as LCD) or an electroluminescence display device. When the display device 100 is an electroluminescence display device, the electroluminescence display device may be an organic light-emitting diode (abbreviated as OLED) or a quantum dot light-emitting diode (abbreviated as QLED).

[0069] In some embodiments, as shown in FIG. 1, a display device 100 includes: ,centre The display device includes a frame 1, a cover plate 2, a touch display panel 3, and a flexible printed circuit board 4 connected to the touch display panel 3 by bonding.

[0070] Here, combining Figures 2 and 4, the flexible printed circuit board 4 can be folded along dashed line L toward the rear surface of the touch display panel 3 (i.e., the side away from the display surface of the touch display panel 3), thereby allowing the flexible printed circuit board 4 to be positioned on the rear surface of the touch display panel 3.

[0071] child Here, the touch display panel 3 may be a flexible touch display panel or a rigid touch display panel. When the touch display panel 3 is a flexible touch display panel, the display device 100 is a flexible display device.

[0072] Here, the vertical cross section of the frame 1 is U-shaped. The touch display panel 3, the flexible printed circuit board 4 and other components are all provided within the frame 1. The flexible printed circuit board 4 is provided below the touch display panel 3 (the side away from the display surface of the touch display panel 3). The cover plate 2 is provided on the side of the touch display panel 3 away from the flexible printed circuit board 4. When the display device 100 is a liquid crystal display device, the display device 100 includes a backlight assembly provided between the touch display panel 3 and the flexible printed circuit board 4.

[0073] As shown in FIG. 2, the touch display panel 3 includes a display panel 31 and a touch layer 32 that may be provided on the light-emitting surface of the display panel 31. The touch layer 32 can obtain coordinate information from an external input (e.g., a touch by a user's finger), that is, the touch layer 32 may be a touch panel that senses the user's touch, or a fingerprint sensing panel that obtains fingerprint information of the user's finger. For example, the touch layer 32 can sense the external input by a capacitive method. Of course, the sensing method of the touch layer 32 includes, but is not limited to, the above-mentioned embodiments, and other suitable sensing methods should also be included in the scope of protection of the present disclosure.

[0074] In some embodiments, FIG. , FIG. 3A and FIG. 3B As shown in The display device 100 is an organic electroluminescent display device. In this case, The display device 100 further includes a polarizer 5 located between the cover plate 2 and the touch layer 32. The polarizer 5 is used to reduce reflected light caused by external light reflected by metal structures in the display panel 3. Here, the polarizer 5 and the cover plate 2 are attached by an optical adhesive 6.

[0075] 3A and 3B, the display panel 31 is an organic electroluminescence display panel. In this case, the display panel 31 includes a display substrate 311 and a sealing layer 312 for sealing the display substrate 311.

[0076] Here, the sealing layer 312 may be a sealing thin film or a sealing substrate.

[0077] 3A and 3B, each sub-pixel in the display substrate 311 includes a light-emitting element and a pixel driving circuit disposed on a first base Sub1. The pixel driving circuit includes a plurality of thin film transistors 3111. (FIGS. 3A and 3B show only one thin film transistor electrically connected to a light emitting element.)The thin film transistor 3111 includes an active layer, a source electrode, a drain electrode, a gate electrode, and a gate insulating layer. The source electrode and the drain electrode are respectively in contact with the active layer. The light-emitting element includes an anode 3112, a light-emitting functional layer 3113, and a cathode 3114. The anode 3112 is electrically connected to the source electrode or the drain electrode of the thin film transistor 3111, which is the driving transistor of the plurality of thin film transistors 3111. FIG. 3A and FIG. 3B show as an example that the anode 3112 is electrically connected to the drain electrode of the thin film transistor 3111.

[0078] The display substrate 311 further includes a pixel definition layer 3115 having a plurality of opening regions, and one light emitting element is provided in one opening region.

[0079] In some embodiments, the light-emitting functional layer 3113 includes only a light-emitting layer. In other embodiments, the light-emitting functional layer 3113 further includes at least one of an electron transporting layer (ETL), an electron injection layer (EIL), a hole transporting layer (HTL), and a hole injection layer (HIL) in addition to the light-emitting layer.

[0080] As shown in FIGS. 3A and 3B, the display substrate 311 further includes a planarization layer 3116 provided between the thin film transistor 3111 and the anode 3112 .

[0081] In some embodiments, as shown in Fig. 3A, the touch layer 32 may be directly disposed on the encapsulation layer 312, i.e., no other film layer may be disposed between the touch layer 32 and the encapsulation layer 312. Illustratively, the touch layer 32 may be formed on the encapsulation layer 312 of the display panel 31 in a continuous process, i.e., after the encapsulation layer 312 of the display panel 31 is formed, the touch layer 32 may be directly formed on the encapsulation layer 312 of the display panel 31, so that the thickness of the touch display panel 31 is relatively thin, which is advantageous for making the display device light and thin.

[0082] In some other embodiments, as shown in FIG. 3B, the touch layer 32 can be formed as a separate element and attached onto the sealing layer 312 of the display panel 31 via an adhesive layer 7. Here, when the touch layer 32 is formed as a separate element (for example, a single film layer), the touch layer 32 can be formed as a single element, such as a touch electrode, a touch electrode layer ... 320 It may further include a carrier film 33 for carrying the

[0083] There is no limitation on the material of the carrier film 33. Exemplarily, the carrier film 33 may be at least one of a resin film, a glass substrate, and a composite film.

[0084] There is no limitation on the material of the adhesive layer 7. Exemplarily, the adhesive layer 7 may be at least one of a pressure sensitive adhesive (abbreviation: PSA), an optically clear adhesive (abbreviation: OCA), and an optically clear resin (abbreviation: OCR).

[0085] 3C and 3D, the display panel 31 is a liquid crystal display panel. The liquid crystal display panel includes an array substrate 313 and a counter substrate 314 disposed opposite each other, and a liquid crystal layer 315 disposed between the array substrate 313 and the counter substrate 314.

[0086] Each sub-pixel of the array substrate 313 includes a thin film transistor 3111 and a pixel electrode 3131, both of which are located on one first base Sub1. The pixel electrode 3131 is electrically connected to the source electrode or the drain electrode of the thin film transistor 3111. Figures 3C and 3D show the electrical connection between the pixel electrode 3131 and the drain electrode of the thin film transistor 3111.

[0087] In some embodiments, the array substrate 313 further includes a common electrode 3132 disposed on the first base Sub1. The pixel electrode 3131 and the common electrode 3132 may be disposed in the same layer, in which case the pixel electrode 3131 and the common electrode 3132 are comb-tooth structures including a plurality of strip-shaped sub-electrodes. The pixel electrode 3131 and the common electrode 3132 may be disposed in different layers. In this case, as shown in FIG. 3C and FIG. 3D, a first insulating layer 3133 is disposed between the pixel electrode 3131 and the common electrode 3132. When the common electrode 3132 is disposed between the thin film transistor 3111 and the pixel electrode 3131, a second insulating layer 3134 is disposed between the common electrode 3132 and the thin film transistor 3111, as shown in FIG. 3C and FIG. 3D.

[0088] In some alternative embodiments, the common electrode 3132 is provided on the opposing substrate 314 .

[0089] The opposing substrate 314 includes one second base Sub2.

[0090] 3C and 3D, the LCD panel further includes a color filter layer CF and a black matrix pattern BM. Here, the color filter layer CF includes at least a red photoresist unit disposed in the red sub-pixel, a green photoresist unit disposed in the green sub-pixel, and a blue photoresist unit disposed in the blue sub-pixel. The black matrix pattern BM is used to separate the light emitted from different sub-pixels, and has the function of reducing the reflected light generated after the external ambient light enters the inside of the display panel 31.

[0091] As shown in Figures 3C and 3D, the color filter layer CF and the black matrix pattern BM may be provided on the second base Sub2 of the counter substrate 314, i.e., the counter substrate 314 includes the color filter layer CF and the black matrix pattern BM. In this case, the thin film transistor 3111 and the black matrix pattern BM are provided on different bases, i.e., on the first base Sub1 and the second base Sub2, respectively. Of course, the color filter layer CF and the black matrix pattern BM may be provided on the array substrate 313, i.e., the array substrate 313 includes the color filter layer CF and the black matrix pattern BM. In this case, the liquid crystal display panel adopts Color Filter on Array (COA) technology.

[0092] As shown in Figures 3C and 3D, the liquid crystal display panel further includes an upper polarizer 316 provided on the side of the counter substrate 314 away from the liquid crystal layer 315, and a lower polarizer 317 provided on the side of the array substrate 313 away from the liquid crystal layer 315.

[0093] As shown in FIG. 3C, the touch layer 32 is Counter substrate 314 and the upper polarizer 316 (i.e., On Cell). As shown in FIG. 3D, the touch layer 32 may be Array substrate 313 and Liquid crystal layer 315 Between To Established Here, the position of the touch layer 32 is not limited to these, and for example, the touch layer 32 may be provided on the side of the cover plate 2 closer to the display panel 31.

[0094] In some embodiments, as shown in FIG. 2, the display panel 31 has a display area A1 and a peripheral area A2 located on at least one side of the display area A1. FIG. 2 shows an example in which the peripheral area A2 surrounds the display area A1. Here, the display area A1 is an area that displays an image, and the display area A1 is arranged to accommodate sub-pixels. The peripheral area A2 is an area that does not display an image, and the peripheral area A2 is DriveFor example, a gate electrode driving circuit may be provided in the peripheral region A2.

[0095] Based on this, as shown in Fig. 2, the cover plate 2 may include a light-transmitting region C1 and a light-shielding region C2. The light-transmitting region C1 may at least partially overlap with the display region A1 of the display panel 31. Light emitted from the display panel 31 may pass through the light-transmitting region C1 of the cover plate 2 and be emitted to the outside so as to be seen by the human eye. The light-shielding region C2 may be provided around the light-transmitting region C1 and may at least partially overlap with the peripheral region A2 of the display panel 31.

[0096] In some embodiments, the touch layer 32 includes a touch area B1 and a peripheral area B2 disposed on at least one side of the touch area B1, as shown in Fig. 2. Fig. 2 shows an example in which the peripheral area B2 surrounds the touch area B1, where the touch area B1 is arranged to accommodate a plurality of touch electrodes, and the peripheral area B2 is arranged to accommodate wiring.

[0097] Exemplarily, the peripheral region B2 of the touch layer 32 surrounds the touch region B1. In this case, the touch layer 32 includes a plurality of touch electrodes provided in the touch region B1; and a plurality of first touch leads 321, a plurality of second touch leads 322, a plurality of first through holes 21, and a plurality of second through holes 22 provided in the peripheral region B2. The plurality of first through holes 21 and the plurality of second through holes 22 are concentrated at both ends of the peripheral region B2 close to the flexible printed circuit board 4 of the touch layer 32, respectively.

[0098] Correspondingly, the peripheral area A2 of the display panel 31 surrounds the display area A1. As shown in Figure 7,A bonding portion is provided in the peripheral region A2 of the display panel 31. The bonding portion includes a plurality of first bonding pads 36 (see FIG. 7) and a plurality of second bonding pads 37 (see FIG. 7), and the plurality of first bonding pads 36 and the plurality of second bonding pads 37 are concentrated and distributed at both ends of the peripheral region A2 close to the flexible printed circuit board 4 of the display panel 31.

[0099] In this case, one end of each of the first touch leads 321 is electrically connected to one touch electrode, and the other end is electrically connected to the first bonding pad 36 of the display panel 31 via the first through hole 21. One end of each of the second touch leads 322 is electrically connected to one touch electrode, and the other end is electrically connected to the second bonding pad 37 of the display panel 31 via the second through hole 22.

[0100] The touch electrodes include touch emission electrodes Tx and touch reception electrodes Rx, where the first touch lead 321 may be a lead of the touch emission electrodes Tx and / or a lead of the touch reception electrodes Rx, and the second touch lead 322 may be a lead of the touch emission electrodes Tx and / or a lead of the touch reception electrodes Rx, and the present disclosure Example of the implementation is not limited to this.

[0101] Based on this, in order to reduce interference from external signals to the signals of the touch leads (including the first touch lead 321 and the second touch lead 322), the following is described with reference to FIGS. 2, 4 and 5. 7 , the touch layer 32 further includes at least one first shield wiring 323 provided on a side of the first touch lead 321 away from the second touch lead 322, and at least one second shield wiring 324 provided on a side of the second touch lead 322 away from the first touch lead 321. Each of the first shield wirings 323 is electrically connected to a first bonding pad 36 in the display panel 31 via a first through hole 21. Each of the second shield wirings 324 is electrically connected to a second bonding pad 37 in the display panel 31 via a second through hole 22.

[0102] In addition, in order to reduce signal interference occurring between the leads of the touch emission electrodes Tx and the leads of the touch reception electrodes Rx, when the first touch lead 321 includes the leads of the touch emission electrodes Tx and the leads of the touch reception electrodes Rx, and the second touch lead 322 includes the leads of the touch emission electrodes Tx and the leads of the touch reception electrodes Rx, as shown in FIG. 2, FIG. 4, and FIG. 7 , the touch layer 32 further includes a first shield wiring 323 provided between the lead wire of the touch emission electrode Tx and the lead wire of the touch reception electrode Rx adjacent to each other in the first touch lead 321, and a second shield wiring 324 provided between the lead wire of the touch emission electrode Tx and the lead wire of the touch reception electrode Rx adjacent to each other in the second touch lead 322. Each of the first shield wirings 323 is electrically connected to a first bonding pad 36 in the display panel 31 via a first through hole 21. Each of the second shield wirings 324 is electrically connected to a second bonding pad 37 in the display panel 31 via a second through hole 22.

[0103] In this case, by bonding and connecting the flexible printed circuit board 4 and the touch display panel 3, the first touch lead 321, the second touch lead 322, the first shield wiring 323, and the second shield wiring 324 are all electrically connected to the touch chip 4100. Here, in order to realize a touch function, the first touch lead 321 and the second touch lead 322 are electrically connected to a touch terminal of the touch chip 4100. In order to reduce interference of an external signal with the signal of the touch lead and to reduce signal interference occurring between the lead of the touch emission electrode Tx and the lead of the touch reception electrode Rx, the first shield wiring 323 and the second shield wiring 324 are electrically connected to a ground terminal of the touch chip 4100.

[0104] In order to reduce the area of ​​the flexible printed circuit board 4, thereby reducing the manufacturing cost of the flexible printed circuit board 4 and facilitating the design of wiring in the flexible printed circuit board 4, in some related technologies, the flexible printed circuit board 4 includes a main flexible printed circuit board 43 and a bridge flexible printed circuit board 44. The main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 are connected by a connector. The connector has a large structure and occupies a large area in the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44. In addition, manual insertion and connection is required to connect the connector, which is inefficient, and therefore increases the labor costs for manufacturing the flexible printed circuit board 4 and the costs of the connector.

[0105] As shown in Figures 4, 5 and 6, some embodiments of the present disclosure provide a display device. The display device includes a display panel 31, a touch layer 32 provided on a light-emitting surface of the display panel 31, and a flexible printed circuit board 4 bonded to the display panel 31. The flexible printed circuit board 4 includes a main flexible printed circuit board 43 and a bridge flexible printed circuit board 44.

[0106] 2, the shape of the display panel 31 in plan view may be substantially rectangular. Here, the term "rectangle" includes not only a substantially rectangular shape, but also a shape similar to a rectangle in consideration of process conditions. Based on this, the display panel 31 has long sides and short sides. In some embodiments, the positions where the long sides and short sides of the display panel 31 intersect each other (i.e., corners) are right angles, so that the shape of the display panel 31 in plan view is rectangular. In other embodiments, the corners of the display panel 31 are curved, i.e., the corners are smooth, so that the shape of the display panel 31 in plan view is a rectangle with rounded corners.

[0107] In some embodiments, as shown in FIG. Orthogonal projection on the display panel 31may overlap the display panel 31. Illustratively, the size of the touch layer 32 may be approximately the same as the size of the display panel 31. A and Figure 3 B As shown in FIG. 1, the edges of the touch layer 32 may be aligned with the edges of the display panel 31. Example of the implementation is not limited to this. Example In terms of touch layer 32 Orthogonal projection on the display panel 31 may only partially overlap the display panel 31, for example the touch layer 32 Orthogonal projection on the display panel 31 may at least partially overlap with the display area A1 of the display panel 31.

[0108] Here, when the size of the touch layer 32 is approximately the same as the size of the display panel 31, the touch area B1 corresponds to the display area A1, and the peripheral area B2 corresponds to the peripheral area A2.

[0109] As shown in Figures 4 and 5, The main flexible printed circuit board 43 includes a first substrate 410, a plurality of pads P, a touch chip 4100, a plurality of first touch connection lines 41A, a plurality of second touch connection lines 42A, and a plurality of third touch connection lines 30A.

[0110] The first substrate 410 has a first welding area 410A and a second welding area 410B. A plurality of pads P are provided in the first welding area 410A and the second welding area 410B. The touch tip 4100 is provided on the first substrate 410. The minimum distance between the touch tip 4100 and the first welding area 410A is smaller than the minimum distance between the touch tip 4100 and the second welding area 410B.

[0111] A plurality of first touch connection lines 41A are provided on the first substrate 410. One end of each of the first touch connection lines 41A is electrically connected to the touch chip 4100, and the other end is electrically connected to one first touch lead line 321 in the touch layer 32 of the display device 100. A plurality of second touch connection lines 42A are provided on the first substrate 410. One end of each of the second touch connection lines 42A is electrically connected to one pad P in the second welding region 410B, and the other end is electrically connected to one second touch lead line 322 in the touch layer 32 of the display device 100. A plurality of third touch connection lines 30A are provided on the first substrate 410. One end of each of the third touch connection lines 30A is electrically connected to one pad P in the first welding region 410A, and the other end is electrically connected to the touch chip 4100.

[0112] As shown in Figures 4 and 6, The bridge flexible printed circuit board 44 includes a second substrate 420, a plurality of pads P, and a plurality of touch conversion lines 420C.

[0113] The second substrate 420 has a third welding area 420A and a fourth welding area 420B. A plurality of pads P are provided in the third welding area 420A and the fourth welding area 420B. One pad P in the third welding area 420A is welded to one pad P in the first welding area 410A, and one pad P in the fourth welding area 420B is welded to one pad P in the second welding area 410B.

[0114] A plurality of touch conversion lines 420C are provided on the second substrate 420. One end of each of the touch conversion lines 420C is electrically connected to one pad P of the third welding area 420A, and the other end is electrically connected to one pad P of the fourth welding area 420B.

[0115] It should be noted that the first substrate 410 and the second substrate 420 are both flexible substrates. The flexible substrate may be one or more of polyethylene terephthalate, ethylene terephthalate, polyether ether ketone, polystyrene, polycarbonate, aromatic polyester, polyarylate, polyimide, polyvinyl chloride, polyethylene, and spun fiber, and the embodiments of the present disclosure are not limited thereto.

[0116] As can be seen from the above, the first touch lead 321 in the touch layer 32 is connected to the touch chip 4100 via the first touch connection line 41A. To the second touch lead 322 in the touch layer 32 can be electrically connected to the touch chip 4100 through the second touch connecting line 42A, the touch conversion line 420C, and the third touch connecting line 30A, so as to transmit the touch signal of the touch layer 32 to the touch chip 4100 for display; Device The touch function can be realized.

[0117] Furthermore, since the flexible printed circuit board 4 according to the embodiment of the present disclosure has the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 welded together, the manufacturing efficiency of the flexible printed circuit board 4 can be improved and costs can be reduced.

[0118] 4, 5 and 6, in some embodiments, the bridge flexible printed circuit board 44 further includes at least one shield conversion line 420D provided on the second substrate 420. One end of each shield conversion line 420D is electrically connected to one pad P of the third welding region 420A, and the other end is electrically connected to one pad P of the fourth welding region 420B. At least one shield conversion line 420D is arranged to be grounded.

[0119] For example, as shown in Figures 4, 5 and 6, when the touch layer 32 includes a first shield wiring 323 and a second shield wiring 324, the main flexible printed circuit board 4 further includes at least one first shield connecting line 41B, at least one second shield connecting line 42B, and at least one third shield connecting line 30B.

[0120] At least one first shield connecting line 41B is provided on the first substrate 410. Each first shield connecting line 41B is arranged so that one end is electrically connected to the touch chip 4100 and the other end is electrically connected to one first shield wiring 323 in the touch layer 32 of the display device 100. At least one second shield connecting line 42B is provided on the first substrate 410. Each second shield connecting line 42B is arranged so that one end is electrically connected to one pad P in the second welding region 410B and the other end is electrically connected to one second shield wiring 324 in the touch layer 32 of the display device 100. At least one third shield connecting line 30B is provided on the first substrate 410. Each third shield connecting line 30B is arranged so that one end is electrically connected to one pad P in the first welding region 410A and the other end is electrically connected to the touch chip 4100.

[0121] The touch conversion line 420C is connected to a pad P corresponding to the second touch connection line 42A and the third touch connection line 30A. The shield conversion line 420D is connected to a pad P connected to the second shield connection line 42B and the third shield connection line 30B.

[0122] As can be seen from the above, the first shield wiring 323 in the touch layer 32 can be electrically connected to the touch chip 4100 through the first shield connecting line 41B; the second shield wiring 324 in the touch layer 32 can be electrically connected to the touch chip 4100 through the second shield connecting line 42B, the shield converting line 420D, and the third shield connecting line 30B. ToIn this case, a ground signal may be input to both the first shielding line 323 and the second shielding line 324 in the touch layer 32, thereby reducing interference with the touch signal.

[0123] In this manner, when the first shield wiring 323 is provided on the side of the first touch lead 321 that is away from the second touch lead 322, and the second shield wiring 324 is provided on the side of the second touch lead 322 that is away from the first touch lead 321, it is possible to reduce interference from external signals with signals of the touch leads (including the first touch lead 321 and the second touch lead 322). The first shield wiring 323 is provided between the lead of the touch emission electrode Tx and the lead of the touch reception electrode Rx adjacent to each other in the first touch lead 321, and the second shield wiring 324 When is provided between the lead wire of the touch emission electrode Tx and the lead wire of the touch reception electrode Rx adjacent to each other in the second touch lead 322, it is possible to reduce signal interference occurring between the lead wire of the touch emission electrode Tx and the lead wire of the touch reception electrode Rx.

[0124] Based on this, as shown in Fig. 6, the bridge flexible printed circuit board 44 includes a plurality of shield conversion lines 420D. The plurality of shield conversion lines 420D includes at least two edge shield conversion lines located on the outermost sides. The above 2 edge shielded conversion wires The ends of one edge-shielded conversion line and the ends of the other edge-shielded conversion line are connected in sequence. The touch conversion lines 420C are connected to each other to form a ring. Each of the touch conversion lines 420C is provided inside the ring. In this way, it is possible to reduce interference from other signals (for example, signals of high-frequency signal lines on the main flexible printed circuit board 43) to the signals of the touch conversion lines 420C located inside the ring.

[0125] The size of the welding area (including the first welding area 410A, the second welding area 410B, the third welding area 420A, and the fourth welding area 420B) is not limited. Exemplarily, the size of each welding area is (3.84±0.05) mm×(3.84±0.05) mm, for example, 3.84 mm×3.84 mm. In the same welding area, the distance between the center of the leftmost pad P and the center of the rightmost pad P is 2.49 mm to 2.84 mm, for example, 2.49 mm, 2.54 mm, 2.59 mm, 2.64 mm, 2.69 mm, 2.74 mm, 2.79 mm, 2.84 mm, for example, 2.66 mm.

[0126] The number of pads P on each welding area is not limited. Exemplarily, the number of pads P on each welding area may be in the range of 20 to 50, for example, the number of pads P on each welding area may be in the range of 20, 25, 30, 35, 40, 45, 50, for example, 25.

[0127] Based on this, the number of pads P in the first welding area 410A, the number of pads P in the second welding area 410B, the number of pads P in the third welding area 420A, and the number of pads P in the fourth welding area 420B may be equal or unequal. Exemplarily, referring to Fig. 4 and Fig. 25, the number of pads P in the first welding area 410A, the second welding area 410B, the third welding area 420A, and the fourth welding area 420B is equal to each other, and each is 25.

[0128] In addition, in order to ensure that the two adjacent pads P are not welded to each other, the pad P in the third welding area 420A and the pad P in the fourth welding area 420B are connected by a conversion line (which may include only the touch conversion line 420C, or may include the touch conversion line 420C and the shield conversion line 420D). This prevents the phenomenon of short circuiting from occurring. As shown in FIG. 25, there is a certain interval B between the two adjacent pads P, and the length of the interval B is 1.0 mm or less. Exemplarily, the interval B between the two adjacent pads P may be 0.1 mm, 0.3 mm, 0.8 mm, or 1.0 mm.

[0129] Here, the distance B between two adjacent pads P is the shortest distance between the edges of the two adjacent pads P.

[0130] In some embodiments, the maximum radial size of the pad P is 1.0 mm or less. Exemplarily, the maximum radial size of the pad P may be 0.1 mm, 0.3 mm, 0.8 mm, or 1.0 mm. In this case, the size of the pad P is relatively small, and the area occupied by the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 of the flexible printed circuit board 4 is relatively small, so that the flexible printed circuit board 4 can be further lightened and thinned, and the structure can be further simplified.

[0131] The shape of the outer contour of the pad P is not limited. Illustratively, the shape of the outer contour of the pad P may be circular, square, rectangular, or irregular. It is obvious to those skilled in the art that the shape of the outer contour of the pad P includes, but is not limited to, the shapes mentioned above. Any shapes should be within the scope of protection of the embodiments of the present disclosure, and are not listed here.

[0132] In some embodiments, as shown in Fig. 22, when the outer contour of the pad P approximates a square, the size A of the diagonal of the square is the maximum size in the radial direction of the pad P. In other embodiments, as shown in Fig. 23, when the outer contour of the pad P approximates a rectangle, the size A of the diagonal of the rectangle is the maximum size in the radial direction of the pad P.

[0133] In still other embodiments, as shown in FIG. 24, when the outer contour of the pad P has an irregular shape, the maximum distance A between any two points on the edge of the pad P is the maximum size of the pad P in the radial direction. In still other embodiments, when the outer contour of the pad P approximates a circle, the diameter of the circle is the maximum size of the pad P in the radial direction. In this case, the diameter range of the pad P is 0.25 mm to 0.35 mm. Exemplarily, the diameter of the circular pad P may be 0.25 mm, 0.3 mm, or 0.35 mm.

[0134] In some embodiments, the third welding area 420A and the fourth welding area 420B are provided on opposite ends of the second substrate 420. The orthogonal projection of the second substrate 420 on the main flexible printed circuit board 43 may or may not be a centrosymmetric figure.

[0135] For example, as shown in FIG. 11, the third welding area 420A and the fourth welding area 420B are provided on opposite ends of the second substrate 420, and the orthogonal projection of the second substrate 420 on the main flexible printed circuit board 43 is a centrosymmetric figure.

[0136] 12, the third welding area 420A and the fourth welding area 420B are provided at both opposing ends of the second substrate 420, and the orthogonal projection of the second substrate 420 on the main flexible printed circuit board 43 is not a centrally symmetrical figure. For example, a bump is provided at the center of the side at one end of the second substrate 420 where the third welding area 420A is provided, extending to the side away from the fourth welding area 420B of the third welding area 420A. That is, the side at one end of the orthogonal projection of the second substrate 420 on the main flexible printed circuit board 43 corresponding to the third welding area 420A is configured by sequentially connecting multiple line segments. The side at one end of the orthogonal projection of the second substrate 420 on the main flexible printed circuit board 43 corresponding to the fourth welding area 420B is one line segment. In this case, since the orthogonal projection of the second substrate 420 onto the main flexible printed circuit board 43 is not a centrally symmetric figure, when the bridge flexible printed circuit board 44 and the main flexible printed circuit board 43 are aligned, attached and welded, it is possible to prevent the third welding area 420A and the fourth welding area 420B from being attached in the reversed positions to the first welding area 410A and the second welding area 410B.

[0137] In some embodiments, referring to FIG. 6, third weld area 420A and Fourth welding area 420B To teeth both Pad P on row M is established. , where M≧2. At least 2M pads P are distributed between the two outermost conversion lines among the multiple conversion lines on the second substrate 420 (which may include only the touch conversion line 420C, or may include the touch conversion line 420C and the shield conversion line 420D).

[0138] For example, when M≧2 and each row of pads P in the third welding area 420A or the fourth welding area 420B includes one pad P, there are only 2M pads P between the two outermost conversion lines. For example, when M=2 and each row of pads P in the third welding area 420A or the fourth welding area 420B includes one pad P, there are four pads P distributed between the two outermost conversion lines.

[0139] For example, when M≧2 and each row of pads P in the third welding area 420A or the fourth welding area 420B includes two pads P, the number of pads P distributed between the two outermost conversion lines is greater than 2M. For example, when M=2 and each row of pads P in the third welding area 420A or the fourth welding area 420B includes two pads P, eight pads P are distributed between the two outermost conversion lines.

[0140] 4 and 5, in some embodiments, the main flexible printed circuit board 43 is arranged to be bonded to the display panel 31 of the display device 100. The first welding area 410A and the second welding area 410B are arranged side by side in a first direction X. The first direction X is approximately parallel to the extension direction of the side of the main flexible printed circuit board 43 close to the display panel 31.

[0141] Based on this, and referring to FIGS. 5, 25 and 26A, the pads P in the third welding area 420A and the pads P in the fourth welding area 420B are both arranged in multiple rows. At least one row of pads P of the third welding area includes a plurality of pads P arranged along the first direction X, and at least one row of pads P of the fourth welding area includes a plurality of pads P arranged along the first direction X. At least one row of pads P includes a plurality of pads P arranged along a first direction X. Two adjacent rows of pads P are offset from each other along a second direction Y. The second direction Y is approximately perpendicular to the first direction X. Thus, when the area of ​​the welding area is constant, the distance between two adjacent pads P is relatively large. Therefore, when the pads P in the third welding area 420A and the fourth welding area 420B are connected by a conversion line, OneContact between a pad P and an adjacent pad P can be avoided to avoid short circuit problems.

[0142] In some embodiments, referring to FIG. 6, the second substrate 420 has a transition wiring region T and connection sector regions S located on opposite ends of the transition wiring region T. The transition wiring region and the connection sector region are located between the third weld region and the fourth weld region. The conversion line includes a transition segment M and connection segments N located at opposite ends of the transition segment. The transition segment M extends along a first direction X and is disposed in a transition wiring region T. The connection segment N is disposed in a connection sector region S. A minimum width of the connection sector region S in the second direction Y is equal to or greater than a width of the transition wiring region T in the second direction Y.

[0143] In addition, along the second direction Y, the width of the transition wiring region T is approximately equal to the spacing between the transition segments M of the two outermost transform lines among the multiple transform lines. Along the second direction Y, the width of the connection sector region S is approximately equal to the spacing between the connection segments N of the two outermost transform lines among the multiple transform lines.

[0144] 6, the width in the second direction Y of the connection sector area close to the third welding area 420A gradually increases from the fourth welding area 420B to the third welding area 420A in the first direction X. Similarly, the width in the second direction Y of the connection sector area close to the fourth welding area 420B gradually increases from the third welding area 420A to the fourth welding area 420B in the first direction X.

[0145] In some embodiments, As shown in Figure 6, The width of the transition wiring area in the second direction Y is smaller than the maximum width of the third welding area 420A in the second direction Y; and / or the width of the transition wiring area in the second direction Y is smaller than the maximum width of the fourth welding area 420B in the second direction Y.

[0146] In some embodiments, As shown in Figure 6, of the connection sector area close to the third weld area 420A. Part , maximum width in the second direction Y but , greater than the maximum width in the second direction Y of the third welded area 420A; and / or of the connection sector area close to the fourth welded area 420B Part , maximum width in the second direction Y but , which is greater than the maximum width in the second direction Y of the fourth welding area 420B.

[0147] Thus, the conversion wires may enter the welding area from multiple sides and electrically connect to corresponding pads P. For example, the conversion wires may be connected to the pads P of the first row in the welding area. final The welding area may be entered from an area other than the area between the pads P of the row to electrically connect to the corresponding pad P. This may facilitate wiring and prevent crosstalk of touch signals.

[0148] In some embodiments, As shown in Figure 6, The pads P in the third welding area 420A and the pads P in the fourth welding area 420B are both arranged in multiple rows, At least one row of pads P of the third welding area includes a plurality of pads arranged along a first direction X, and at least one row of pads P of the fourth welding area includes a plurality of pads arranged along a first direction X. The at least one row of pads P includes a plurality of pads arranged along the first direction X. At least one conversion line among the plurality of conversion lines on the second substrate 420 passes through an area of ​​the third welding area 420 and the fourth welding area 420B other than an area between the pads P of the first row and the pads P of the last row, and is electrically connected to a corresponding pad P.

[0149] Exemplarily, two rows of pads P are provided in each of the third welding area 420A and the fourth welding area 420B on the second substrate 420. The first row of pads P in the third welding area 420A and the fourth welding area 420B includes one pad P, and the second row of pads P includes two pads P. In this case, the number of conversion lines on the second substrate 420 is three. Optionally, one of the three conversion lines is connected to the second row of pads P. The side away from pad P of the first row of pad PAlternatively, two rows of pads P are provided in each of the third welding area 420A and the fourth welding area 420B on the second substrate 420. The first row of pads P in the third welding area 420A and the fourth welding area 420B includes two pads P, and the second row of pads P includes one pad P. In this case, the number of conversion lines on the second substrate 420 is three. Optionally, one of the three conversion lines passes through the first row of pads P. The side away from pad P of the second row of pad P Pass through the area.

[0150] Exemplarily, two rows of pads P are provided in each of the third welding area 420A and the fourth welding area 420B on the second substrate 420. Each row of pads P in the third welding area 420A or the fourth welding area 420B includes two pads P. In this case, the number of conversion lines on the second substrate 420 is four. Optionally, two of the four conversion lines are arranged such that one conversion line is arranged in the first row of pads P. The side away from pad P of the second row of pad P Another conversion line passes through the area of ​​the second row of pad P. The side away from pad P of the first row of pad P Pass through the area.

[0151] Exemplarily, three rows of pads P are provided in both the third welding area 420A and the fourth welding area 420B on the second substrate 420. Each row of pads P in the third welding area 420A or the fourth welding area 420B includes three pads P. In this case, the number of conversion lines on the second substrate 420 is nine. Optionally, the first row of pads P in the third welding area 420A and the first row of pads P in the fourth welding area 420B are connected by three conversion lines; two conversion lines are connected to the first row of pads P. The side away from pad P of the third row of pad P The third row of pads P in the third welding area 420A and the third row of pads P in the fourth welding area 420b are connected by three conversion lines, and two conversion lines are connected to the third row of pads P. The side away from pad P of the first row of pad P Pass through the area.

[0152] In some embodiments, referring to FIG. 6, both ends of one of the two outermost conversion lines of the plurality of conversion lines on the second substrate 420 are: The third welding area The side of the first row of pad P away from the last row of pad P and on the side away from the pad P in the last row of the pad P in the first row of the fourth welding area, The other conversion line is electrically connected to the two pads P that are the furthest apart among the first row pads P of the third welding area 420A and the first row pads P of the fourth welding area 420B; The third welding area The side of the last pad P away from the first pad P and on the side of the last row of pads P in the fourth welding area away from the first row of pads P. , and are electrically connected to the two pads P that are furthest apart among the pads P in the last row of the third welding area 420A and the pads P in the last row of the fourth welding area 420B.

[0153] Exemplarily, referring to FIG. 6, a third welded region 420A and a fourth welded region 420B To teeth, both M row pad is established. , where M≧2. The bridge flexible printed circuit board 44 includes a plurality of shield conversion lines 420D. The plurality of shield conversion lines 420D include at least two edge shield conversion lines located on the outermost sides. Of the two edge shield conversion lines, both ends of one edge shield conversion line are The third welding area The side of the first row of pad P away from the last row of pad P and on the side of the pad P in the first row of the fourth welding area away from the pad P in the last row. , electrically connected to the two pads P that are farthest from each other among the pads P in the first row of the third welding area 420A and the pads P in the first row of the fourth welding area 420B; The third welding area The side of the last pad P away from the first pad P and on the side of the pad P in the last row of the fourth welding area away from the pad P in the first row. The pads P are electrically connected to the two pads P that are furthest apart from each other among the pads P in the last row of the third welding area 420A and the pads P in the last row of the fourth welding area 420B.

[0154] Exemplarily, two rows of pads P are provided in each of the third welding area 420A and the fourth welding area 420B on the second substrate 420. Each row of pads P in the third welding area 420A or the fourth welding area 420B includes two pads P. In this case, the number of conversion lines on the second substrate 420 is four. Optionally, two of the four conversion lines are arranged such that one conversion line is arranged in the first row of pads P. The side away from pad P of the second row of pad Pand electrically connects to the two pads P that are the furthest apart among the pads P in the first row of the third welding area 420A and the pads P in the first row of the fourth welding area 420B, and another conversion line connects to the pads P in the second row of the pads P. The side away from pad P of the first row of pad P and electrically connects to the two pads P that are furthest apart among the pads P in the second row of the third welding area 420A and the pads P in the second row of the fourth welding area 420B.

[0155] It should be understood that the multiple conversion lines (which may include only the touch conversion line 420C, or may include the touch conversion line 420C and the shield conversion line 420D) may be located on the same side of the second substrate 420, or on opposing sides of the second substrate 420.

[0156] In some embodiments, as shown in FIG. 27, FIG. 30A, and FIG. 30B, the pad P on the second substrate 420 is a via pad. The second substrate 420 has a plurality of vias 421, and each via 421 corresponds to one via pad. The via pad includes two solder lugs 422 and a conductive connection layer 423. The two solder lugs 422 are provided on a surface of the second substrate 420 close to the main flexible printed circuit board 43 and a surface away from the main flexible printed circuit board 43, respectively. The via 421 corresponding to the via pad penetrates the second substrate 420 between the two solder lugs 422 of the via pad and the two solder lugs 422. The conductive connection layer 423 covers the sidewall of the via 421, and both ends are electrically connected to the two solder lugs 422, respectively. 27, the conductive connection layer 423 may include a conductive film 11 and an oxidation-resistant metal layer (also referred to as a second metal pattern 15) provided on the side of the conductive film 11 away from the second substrate 420.

[0157] In this way, when the pad P of the main flexible printed circuit board 43 and the via pad on the bridge flexible printed circuit board 44 are welded, the solder overflows from the via 421, and thereby the pad P of the main flexible printed circuit board 43 and the via pad on the bridge flexible printed circuit board 44 are welded. Via pad An electrical connection is established between the

[0158] Here, the conversion line of the flexible printed circuit board 44 may be provided on a surface of the second substrate 420 close to the first substrate 410 and / or on a surface away from the first substrate 410. For example, on both the surface of the second substrate 420 close to the first substrate 410 and the surface away from the first substrate 410, the pad P of the third welding region 420A and the pad P of the fourth welding region 420B may be connected by the conversion line. This makes it easier to wire the bridge flexible printed circuit board 44 and the main flexible printed circuit board 43.

[0159] The shape of the outer contour of the orthogonal projection of the via pad on the second substrate 420 is not limited. Illustratively, the shape of the outer contour of the orthogonal projection of the via pad on the second substrate 420 may be a circle, a square, a rectangle, or an irregular shape. It is obvious to those skilled in the art that the shape of the outer contour of the orthogonal projection of the via pad on the second substrate 420 includes, but is not limited to, the shapes mentioned above. Any shapes are within the scope of protection of the embodiments of the present disclosure and are not listed here.

[0160] In some embodiments, as shown in Figures 26A and 26B, the outer contour of the via pad in the orthogonal projection on the second substrate 420 is substantially circular. In this case, the diameter range D1 of the outer contour of the via pad is 0.25 mm to 0.35 mm. Exemplarily, the diameter D1 of the outer contour of the via pad may be 0.25 mm, 0.3 mm, or 0.35 mm.

[0161] Here, the shape of the inner contour of the orthogonal projection of the via pad on the second substrate 420 is not limited. Illustratively, the shape of the inner contour of the orthogonal projection of the via pad on the second substrate 420 may be circular or X-shaped. It is obvious to those skilled in the art that the shape of the inner contour of the orthogonal projection of the via pad on the second substrate 420 includes, but is not limited to, the shapes mentioned above. Any shape should be within the scope of protection of the embodiments of the present disclosure, and will not be listed here.

[0162] If the diameter range of the via 421 on the via pad is too large, the solder cannot completely fill the via 421, and the via pad of the bridge flexible printed circuit board 44 and the main flexible printed circuit board 43 may be damaged. Pad if the diameter range of the via 421 on the via pad is too small, the air cannot be exhausted from the via 421 during welding, and the solder cannot be sufficiently filled in the via 421, resulting in a problem of solder leakage.

[0163] Considering this, in some embodiments, as shown in Figure 26A, the inner contour of the orthogonal projection of the via pad on the second substrate 420 is approximately circular, and the diameter range of the inner contour of the via pad is 0.05mm to 0.15mm. Exemplarily, the diameter of the circular pad may be 0.05mm, 0.1mm, or 0.15mm.

[0164] In some other embodiments, as shown in FIG. 26B, the inner contour of the orthogonal projection of the via pad on the second substrate 420 is substantially X-shaped. In this case, the range of diameter D2 of the circumscribing circle corresponding to the X-shaped inner contour is 0.05 mm to 0.2 mm. Exemplarily, the diameter D2 of the circumscribing circle corresponding to the X-shaped inner contour may be 0.05 mm, 0.1 mm, or 0.2 mm.

[0165] In this way, when the via pads of the bridge flexible printed circuit board 44 and the pads P of the main flexible printed circuit board 43 are welded together, the air can be efficiently discharged through the vias 421 corresponding to the via pads, and the vias 421 can be sufficiently filled with solder, which facilitates visual inspection and prevents solder leakage.

[0166] In some embodiments, the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 are two-layer boards. That is, the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 each have two conductive layers. As shown in FIG. 13 , a conductive film 11 is provided on both the side of the first substrate 410 close to the second substrate 420 and the side of the first substrate 410 remote from the second substrate 420, and the conductive film 11 is connected to the first substrate 410 by an adhesive layer 12. A conductive film 11 is provided on both the side of the second substrate 420 close to the first substrate 410 and the side of the second substrate 420 remote from the first substrate 410, and the conductive film 11 is connected to the second substrate 420 by an adhesive layer 12. .Ma Alternatively, as shown in FIG. 14, the conductive film 11 may be formed directly on the first substrate 410 and the second substrate 420 .

[0167] In some embodiments, in the main flexible printed circuit board 43, the conductive film 11 close to the bridge flexible printed circuit board 44 may form a plurality of pads P and each wiring in the first welding area 410A and the second welding area 410B. Here, referring to FIG. 4, FIG. 19 and FIG. 20, each wiring may include at least one of the first touch connecting line 41A, the second touch connecting line 42A, the third touch connecting line 30A, the first shield connecting line 41B, the second shield connecting line 42B, the third shield connecting line 30B, the ELVDD line, the ELVSS line, the DVDD line and the high frequency signal line 48 (abbreviated as MIPI line). In the main flexible printed circuit board 43, the conductive film 11 away from the bridge flexible printed circuit board 44 may form a bonding pin for bonding with the display panel 31.

[0168] In some embodiments, referring to FIG. 6, FIG. 18 and FIG. 27, in the bridge flexible printed circuit board 44, the conductive film 11 away from the main flexible printed circuit board 43 is 3 Welding Area 4 2 0A and 4 Welding Area 4 218 and 27, in the bridge flexible printed circuit board 44, a main flexible printed circuit board 420B may be formed with a plurality of solder lugs 422, a touch conversion line 420C, and a shield conversion line 420D. 43 The conductive film 11 close to the first 3 Welding Area 4 2 0 A and 4 Welding Area 4 2 0 B A plurality of solder lugs 422 and an electromagnetic interference layer 14 may be formed.

[0169] In some embodiments, the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 are single-layer boards. That is, the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 have only one conductive layer. As shown in FIG. 15, a conductive film 11 is provided on the side of the first substrate 410 close to the second substrate 420 or on the side of the first substrate 410 remote from the second substrate 420, and the conductive film 11 is connected to the first substrate 410 by an adhesive layer 12. Similarly, a conductive film 11 is provided on the side of the second substrate 420 close to the first substrate 410 or on the side of the second substrate 420 remote from the first substrate 410, and the conductive film 11 is connected to the second substrate 420 by an adhesive layer 12. Also, as shown in FIG. 16, the conductive film 11 may be directly formed on the first substrate 410 and the second substrate 420.

[0170] In some embodiments, the conductive film 11 in the main flexible printed circuit board 43 may form a plurality of pads P in the first welding area 410A and the second welding area 410B, each wiring, and a bonding pin bonded to the display panel 31. Here, referring to Fig. 4, Fig. 19 and Fig. 20, each wiring may include at least one of the first touch connecting line 41A, the second touch connecting line 42A, the third touch connecting line 30A, the first shield connecting line 41B, the second shield connecting line 42B, the third shield connecting line 30B, an ELVDD line, an ELVSS line, a DVDD line, and a high-frequency signal line 48 (abbreviated as MIPI line).

[0171] In some embodiments, referring to FIG. 6 and FIG. 15, the conductive film 11 in the bridge flexible printed circuit board 44 is 3 Welding Area 4 2 0A and No. 4 Welding Area 4 2 0B, a plurality of pads P, a touch conversion line 420C, and a shield conversion line 420D may be formed.

[0172] The material of the conductive film 11 is not limited. Exemplarily, the material of the conductive film 11 may be a metal. For example, the material of the conductive film 11 may be copper.

[0173] The material of the adhesive layer 12 is not limited. Ingredients may be at least one of a pressure sensitive adhesive (PSA), an epoxy adhesive, and an acrylic adhesive.

[0174] In some embodiments, the orthogonal projection of the adhesive layer 12 on the first substrate 410 is 0 and The orthogonal projection of the adhesive layer 12 on the second substrate 420 is 0 and The full overlap ensures that the adhesive layer 12 can fully adhere the conductive film 11 to the first substrate 410 or the second substrate 420 .

[0175] 4 and 17, the bridge flexible printed circuit board 44 further includes a protective layer 13 and an electromagnetic interference layer 14. The protective layer 13 and the electromagnetic interference layer 14 are provided on a side of the second substrate 420 close to the main flexible printed circuit board 43, and are provided in order in a direction away from the second substrate 420. In this case, the electromagnetic interference layer 14 can shield the touch conversion line 420C on the bridge flexible printed circuit board 44 from interference from the high frequency signal line 48 on the main flexible printed circuit board 43.

[0176] In addition, the electromagnetic interference layer 14 is provided in an area of ​​the second substrate 420 other than the third welding area 420A and the fourth welding area 420B, thereby avoiding any influence on the welding between the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44.

[0177] The material of the protective layer 13 is not limited. For example, the material of the protective layer 13 is polyimide. Do( Polyimide , abbreviation: PI ) may also be used.

[0178] There is no limitation on the material of the electromagnetic interference layer 14. Illustratively, the material of the electromagnetic interference layer 14 may be a metal, for example, the material of the electromagnetic interference layer 14 may be copper.

[0179] 18, the bridge flexible printed circuit board 44 includes a second substrate 420, a first adhesive layer 121, a second adhesive layer 122, a first conductive film 111, a second conductive film 112, a protective layer 13, and an electromagnetic interference layer 14. Here, the first adhesive layer 121 and the second adhesive layer 122 are provided on both opposing sides of the second substrate 420. The first conductive film 111 is provided on the side of the first adhesive layer 121 that is away from the second substrate 420, and the second conductive film 112 is provided on the side of the second adhesive layer 122 that is away from the second substrate 420. The protective layer 13 is provided on the side of the second conductive film 112 that is away from the second substrate 420. The electromagnetic interference layer 14 is provided on the side of the protective layer 13 that is away from the second substrate 420. The second adhesive layer 122 , the second conductive film 112 , the protective layer 13 , and the electromagnetic interference layer 14 are located on the side of the second substrate 420 closer to the first substrate 410 .

[0180] Here, the thickness of the first substrate 410 and the second substrate 420 may be 25.4 μm, the thickness of the first conductive film 111 and the thickness of the second conductive film 112 may be 14 μm, the thickness of the first adhesive layer 121 and the thickness of the second adhesive layer 122 may be 15 μm, the thickness of the protective layer 13 may be 12.7 μm, and the thickness of the electromagnetic interference layer 14 may be 12 μm.

[0181] Furthermore, when the main flexible printed board 43 and the bridge flexible printed board 44 are welded together using a plurality of pads P, other overlapping areas of the bridge flexible printed board 44 and the main flexible printed board 43 may be bonded with a thermosetting adhesive to increase the connection reliability between the main flexible printed board 43 and the bridge flexible printed board 44. Here, the thickness of the thermosetting adhesive may be 5 μm.

[0182] In some embodiments, As shown in Figure 5, The main flexible printed circuit board 43 further includes a first metal pattern, which is disposed to cover the pads P on the first substrate 410 and prevent the pads P on the first substrate 410 from being oxidized.

[0183] 27, in some embodiments, the bridge flexible printed circuit board 44 further includes a second metal pattern 15. The second metal pattern 15 is disposed to cover the pads P on the second substrate 420 and prevent the pads P on the second substrate 420 from being oxidized.

[0184] The shape of the first metal pattern and the shape of the second metal pattern 15 are as follows: Each corresponds The shape of the first metal pattern and the second metal pattern 15 are substantially the same as that of the pad P. Each corresponds This completely covers the pad P. Each corresponds This has the effect of preventing the pad P from being oxidized. Furthermore, when the pad P of the bridge flexible printed circuit board 44 is a via pad, the second metal pattern 15 further covers the side wall of the via 421 so as to prevent the conductive layer (conductive film 11) in the via 421 from being oxidized.

[0185] The materials of the first metal pattern and the second metal pattern 15 are Each corresponds As long as the pads can be prevented from being oxidized and corroded, there is no limitation. Illustratively, the materials of the first metal pattern and the second metal pattern include a combination of one or two of gold and nickel.

[0186] When the material of the first metal pattern and the second metal pattern 15 is nickel, the thickness of the first metal pattern and the second metal pattern 15 ranges from 2 μm to 4 μm.When the material of the first metal pattern and the second metal pattern 15 is gold, the thickness of the first metal pattern and the second metal pattern 15 is 0.05 μm.

[0187] In some embodiments, the main flexible printed circuit board 43 further includes a first green oil layer and a first resin layer. The first green oil layer covers at least a first region of the first substrate 410, and the first region is a region of the first welding region 410A and the second welding region 410B other than the region where the pad P is provided. The first resin layer covers a region of the first substrate 410 other than the first welding region 410A and the second welding region 410B.

[0188] In some embodiments, the bridge flexible printed circuit board 44 further includes a second green oil layer and a second resin layer. As shown in Fig. 28, Fig. 29A, and Fig. 29B, the second green oil layer covers at least a second region of the second substrate 420. The second region is a region of the third welding region 420A and the fourth welding region 420B other than the region where the pad P is provided. The second resin layer covers the region of the second substrate 420 other than the third welding region 420A and the fourth welding region 420B.

[0189] In addition to applying green oil to the first and second regions, the border of pad P may also be applied with green oil, so as to avoid the solder material from overflowing the area of ​​pad P. It should be understood that when applying green oil to the border of pad P, the green oil may be partially located on pad P, but does not completely cover pad P.

[0190] As shown in Fig. 28, Fig. 29A, and Fig. 29B, Fig. 28 is a schematic diagram of an example in which green oil is applied to a region (second region) other than the region where the pad P is provided in the third welding region 420A and the fourth welding region 420B. Fig. 29A is an enlarged schematic diagram of the third welding region 420A in Fig. 28. Fig. 29B is an enlarged schematic diagram of the fourth welding region 420B in Fig. 28. As is clear from Fig. 29A and Fig. 29B, the green oil layer avoids the regions where the pads P are provided in the third welding region 420A and the fourth welding region 420B.

[0191] 4 and 5, in some embodiments, the first substrate 410 further includes an element region 45. The main flexible printed circuit board 43 further includes at least one element and a third green oil layer. The at least one element is disposed on a side of the first substrate 410 close to the bridge flexible printed circuit board 44, and is located in the element region 45 of the first substrate 410. The third green oil layer covers an area of ​​the element region 45 other than the area where the at least one element is provided.

[0192] There is no limitation on the number of elements. At least one element means that the main flexible printed circuit board 43 includes only one element, or that the main flexible printed circuit board 43 includes two or more elements.

[0193] Here, the element may be at least one of a resistor, a capacitor, and a transistor. Exemplarily, referring to FIG. 4 and FIG. 5, the element may be a first element 4300 including a plurality of resistors, a plurality of capacitors, and a plurality of transistors. The first element 4300 may be electrically connected to the driving chip 4200 of the display panel 3 via a bonding pin on the main flexible printed circuit board 43 and a bonding pad on the display panel 3. Exemplarily, moreover, The element may be a touch chip 4100 with touch functionality that is composed of multiple resistors, multiple capacitors, and multiple transistors.

[0194] Here, the green oil, which is a liquid photo solder resist, is an acrylic oligomer. It can function as a protective layer, the first green oil layer covers the first region, the second green oil layer covers the second region, thereby preventing the occurrence of a short circuit between two adjacent pads P; the third green oil layer covers the region other than the region in which at least one element is provided in the element region 45, thereby preventing the occurrence of a short circuit between two adjacent elements. The "resin" can be one or a combination of two of polyimide (abbreviated as PI) and polyester (abbreviated as PET).

[0195] It is disadvantageous to form a protective layer by applying a resin material because the sizes of the first welding area 410A, the second welding area 410B, the third welding area 420A, the fourth welding area 420B, and the element area 45 are small. In addition, because green oil is relatively expensive, if the areas other than the first welding area 410A and the second welding area 410B on the first substrate 410, and the areas other than the third welding area 420A and the fourth welding area 420B on the second substrate 420 are covered, the manufacturing costs of the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 will be high.

[0196] Based on this, the first region of the first substrate 410 and the region of the element region 45 other than the region in which the element is provided. The first substrate 410 is covered with green oil, and the first and second welding areas 410A and 410B of the first substrate 410 are and element region 45 The other area is covered with resin, and the second area of ​​the second substrate 420 is Area The third welding area 420A and the fourth welding area 420B of the second substrate 420 are covered with green oil. B and above By covering the outer areas, not only can good coating effects be ensured on the surfaces of the first substrate 410 and the second substrate 420, but also the manufacturing costs of the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 can be reduced.

[0197] 5 and 8, the main flexible printed circuit board 43 further includes a support 46. The support 46 is provided on the side of the first substrate 410 away from the bridge flexible printed circuit board 44. The element region 45 is located within the range of the orthogonal projection of the support 46 on the first substrate 410.

[0198] In this case, the support 46 can have the effect of supporting all elements in the element region 45 on the first substrate 410 so that a portion of the element region 45 on the first substrate 410 is not deformed by the weight of the elements, thereby having the effect of protecting the elements in the element region 45.

[0199] In some embodiments, there is a gap between the boundary of the orthogonal projection of the support 46 on the first substrate 410 and the boundary of the element region 45. This gap is 0.5 mm or more. In this case, the support 46 can effectively support all the elements in the element region 45 on the first substrate 410, and the area occupied by the main flexible printed circuit board 43 on the flexible printed circuit board 4 on the side away from the bridge flexible printed circuit board 44 is relatively small. This makes the flexible printed circuit board 4 light and thin, and has a simple structure.

[0200] 9 and 10, in some embodiments, the support 46 includes a metal sheet 460, and a first adhesive layer 461 and a first thin film 462 provided on opposite sides of the metal sheet 460. The first adhesive layer 461 is located on the side of the metal sheet 460 close to the first substrate 410. Based on this, the first adhesive layer 461 is in contact with the surface of the first substrate 410 that is away from the second substrate 420. Combining FIG. 2 and FIG. 4, when the flexible printed circuit board 4 can be folded toward the rear surface of the display panel 31 along the dashed line L so that the flexible printed circuit board 4 is positioned on the rear surface of the display panel 31, the first thin film 462 is in contact with the rear surface of the display panel 31.

[0201] 10, in some embodiments, the orthogonal projection of the first adhesive layer 461 on the first substrate 410 overlaps with the orthogonal projection of the metal sheet 460 on the first substrate 410. That is, the area of ​​the orthogonal projection of the first adhesive layer 461 on the first substrate 410 is equal to the area of ​​the orthogonal projection of the metal sheet 460 on the first substrate 410, and the boundary of the first adhesive layer 461 is aligned with the boundary of the metal sheet 460. In this way, the metal sheet 460 and the first substrate 410 are completely bonded with high connection reliability.

[0202] 9 and 10 , in some embodiments, the orthogonal projection of the first thin film 462 on the first substrate 410 is located within the orthogonal projection of the metal sheet 460 on the first substrate 410. The area of ​​the orthogonal projection of the first thin film 462 on the first substrate 410 is smaller than the area of ​​the orthogonal projection of the metal sheet 460 on the first substrate 410.

[0203] The material of the metal sheet 460 is not limited. Illustratively, the material of the metal sheet 460 is steel. , and At least one of the following: or With them Alloy with silicon For example, the material of the metal sheet 460 is an alloy of silicon and steel. Also, for example, the material of the metal sheet 460 is an alloy of silicon and iron. Also, for example, the material of the metal sheet 460 is steel.

[0204] There is no limitation on the material of the first adhesive layer 461. Exemplarily, the material of the first adhesive layer 461 may be a thermosetting adhesive.

[0205] The material of the first thin film 462 is not limited as long as it can provide a good heat dissipation effect. Illustratively, the first thin film 462 is a heat dissipation graphite film.

[0206] In some embodiments, referring to FIG. 4, FIG. 5 and FIG. 8, the first substrate 410 further includes a bonding area. The bonding area is an area of ​​the first substrate 410 arranged to bond with the display panel 31 of the display device 100. The main flexible printed circuit board 43 further includes a plurality of first bonding pins 4101 and a plurality of second bonding pins 4102. The plurality of first bonding pins 4101 are provided in the bonding area. At least one first bonding pin 4101 is arranged to electrically connect the first touch connection line 41A to a corresponding first touch lead line 321 in the touch layer 32 of the display device 100. The plurality of second bonding pins 4102 are provided in the bonding area, and at least one second bonding pin 4102 is arranged to electrically connect the second touch connection line 42A to a corresponding second touch lead line 322 in the touch layer 32.

[0207] In some embodiments, the bonding regions are sequentially filled from left to right as shown in FIG. arrangement Signal to be Terminals Touch Receipt Electrode Rx signal Terminals , ELVDD+ELVSS signal Terminals , GOA signal Terminals (CLK Signal Terminal , V.G.L. Signal Terminal , V.G.H. Signal Terminal ), data signal control line signal (Data signal) Terminals , GOA signal terminal (CLK signal terminal, VGL signal terminal, VGH signal terminal), ELVSS+ELVDD signal Terminals ,touch injection Electrode Tx signal Terminals Includes.

[0208] In addition, since the current of the ELVDD and ELVSS wiring is large, several pins corresponding to ELVDD or ELVSS on the main flexible printed circuit board 43 are shorted. That is, several ELVDD wirings are connected to each other, or several ELVSS wirings are connected to each other, and finally, they are integrated into one line and electrically connected to the bonding pad of the display panel 3.

[0209] When the main flexible printed circuit board 43 further includes at least one first shield connecting line 41B and at least one second shield connecting line 42B, the at least one first bonding pin 4101 is arranged to electrically connect the first shield connecting line 41B to a corresponding first shield wiring 323 in the touch layer 32; the at least one second bonding pin 4102 is arranged to electrically connect the second shield connecting line 42B to a corresponding second shield wiring 324 in the touch layer 32.

[0210] 4 and 8, in some embodiments, the maximum size L1 of the main flexible printed circuit board 43 is in the range of 55.25 mm≦L1≦55.55 mm along the first direction X. The first direction X is approximately parallel to the extension direction of the side of the main flexible printed circuit board 43 that is closer to the display panel 31.

[0211] In some embodiments, referring to FIG. 4, FIG. 8 and FIG. 21, the bonding region is strip-shaped and extends along a first direction X. A plurality of first bonding pins 4101 and a plurality of second bonding pins 4102 are arranged side by side along the first direction X. The first bonding pins 4101 and the second bonding pins 4102 of the main flexible printed circuit board 43 that are farthest apart along the first direction X are arranged side by side along the first direction X. Distance The range of the distance L2 is 53.55 mm≦L2≦53.85 mm. The range of the maximum size L3 of the bonding region along the second direction Y is 1.2 mm≦L3≦1.6 mm.

[0212] In some embodiments, referring to FIGS. 4, 5 and 8, the main flexible printed circuit board 43 is further provided with a connection portion 47 arranged to be electrically connected to a main board of the display device 100.

[0213] 8, the main flexible printed circuit board 43 has a copper leakage portion A on the side away from the bridge flexible printed circuit board 44. The copper leakage portion A is arranged to be grounded.

[0214] The number of first touch leads 321 included in the touch layer 32 may be the same as or different from the number of first touch connection lines 41A included in the main flexible printed circuit board 43. The number of second touch leads 322 included in the touch layer 32 may be the same as or different from the number of second touch connection lines 42A included in the main flexible printed circuit board 43 and the number of third touch connection lines 30A.

[0215] In some embodiments, the number of the first touch leads 321 included in the touch layer 32 is the same as the number of the first touch connecting lines 41A included in the main flexible printed circuit board 43. The number of the second touch leads 322 included in the touch layer 32 is the same as the number of the second touch connecting lines 42A included in the main flexible printed circuit board 43 and the number of the third touch connecting lines 30A. This arrangement can ensure that the touch chip 4100 can receive multiple different touch signals on the first touch leads 321 and the second touch leads 322, and can prevent crosstalk of touch signals on two adjacent first touch leads 321 or two adjacent second touch leads 322.

[0216] In some other embodiments, due to the size limitation of the peripheral area A2 of the display panel 31, the same touch electrode may be electrically connected to multiple touch leads (the first touch lead 321 or the second touch lead 322) provided in different layers in the peripheral area A2 of the display panel 31, and the multiple touch leads electrically connected to the same touch electrode may be electrically connected to the same touch connection line (the first touch connection line 41A or the second touch connection line 42A). By being provided in this way, the size of the peripheral area A2 of the display panel 31 can be set to be narrower. In addition, it can be ensured that the touch chip 4100 can receive multiple different touch signals on the first touch lead 321 and the second touch lead 322, and further, the occurrence of crosstalk of the touch signals on the two adjacent first touch leads 321 or the two adjacent second touch leads 322 can be prevented.

[0217] When the touch layer 32 includes the first shield wiring 323 and the second shield wiring 324, the main flexible printed circuit board 43 includes the first shield connecting line 41B, the second shield connecting line 42B, and the third shield connecting line 30B correspondingly, and the bridge flexible printed circuit board 44 includes the shield conversion line correspondingly. In this case, the number of the first shield wirings 323 included in the touch layer 32 may be the same as or different from the number of the first shield connecting lines 41B included in the main flexible printed circuit board 43. The number of the second shield wirings 324 included in the touch layer 32 may be the same as or different from the number of the second shield connecting lines 42B and the number of the third shield connecting lines 30B included in the main flexible printed circuit board 43.

[0218] In some embodiments, the number of first shield wirings 323 included in the touch layer 32 is the same as the number of first shield connecting lines 41B included in the main flexible printed circuit board 43; the number of second shield wirings 324 included in the touch layer 32 is the same as the number of second shield connecting lines 42B included in the main flexible printed circuit board 43, and the number of third shield connecting lines 30B.

[0219] In some other embodiments, the number of first shield wirings 323 included in the touch layer 32 is smaller than the number of first shield connecting lines 41B included in the main flexible printed circuit board 43; the number of second shield wirings 324 included in the touch layer 32 is smaller than the number of second shield connecting lines 42B and the number of third shield connecting lines 30B included in the main flexible printed circuit board 43, thereby reducing the area occupied by the first shield connecting lines 41B, the second shield connecting lines 42B and the third shield connecting lines 30B on the main flexible printed circuit board 43, and making the structure of the flexible printed circuit board simpler and the cost lower.

[0220] 4, in some embodiments, the main flexible printed circuit board 43 further includes a plurality of data signal control lines disposed on the first substrate 410. The display panel 31 includes a plurality of data lines Data and a driving chip 4200. The driving chip 4200 is disposed in the peripheral area A2 and is electrically connected to the plurality of data signal control lines and the plurality of data lines Data. The driving chip 4200 is arranged to process signals on the plurality of data signal control lines and output them to the plurality of data lines Data.

[0221] In some embodiments, the sub-pixels in each column in the display panel 31 need to be electrically connected to one data line Data, thereby providing different data signals to the sub-pixels in each column. The wiring (data signal control line) connected to the driving chip 4200 in the flexible printed circuit board 4 only needs to provide driving signals to the driving chip 4200, thereby allowing the driving chip 4200 to output the necessary data signals to the sub-pixels in each column.

[0222] Based on this, in some embodiments, the number of data signal control lines included in the main flexible printed circuit board 43 is less than the number of data lines Data included in the display panel 31. Thus, by gating on the data lines Data, one data signal control line can be used to transmit data signals to multiple data lines Data, thereby reducing the number of channels for transmitting data signals in the driver chip 4200, i.e., the number of data signal control lines. Based on this, the line width of the data signal control line can be made larger than the line width of the data line, thus being advantageous to improving the transmission efficiency of data signals from one data signal control line to multiple data lines Data.

[0223] 5 and 7, the main flexible printed circuit board 43 further includes a first bonding pin 4101 and a second bonding pin 4102; the display panel 31 further includes a plurality of first bonding pads 36 and a plurality of second bonding pads 37. Each of the first bonding pads 36 is electrically connected to one of the first bonding pins 4101 and one of the first touch leads 321. Each of the second bonding pads 37 is electrically connected to one of the second bonding pins 4102 and one of the second touch leads 322.

[0224] Based on this, combining Figures 2 and 4, the flexible printed circuit board 4 may be bonded to the first bonding pad 36 and the second bonding pad 37 on the peripheral area A2 of the display panel 31 by the first bonding pin 4101 and the second bonding pin 4102 (also referred to as golden fingers) on the main flexible printed circuit board 43.

[0225] In some embodiments, the thickness of the first bond pad 36 and the thickness of the second bond pad 37 are both equal to or greater than the thickness of the touch layer. 32 The thickness of the first bonding pad 36 and the second bonding pad 37 is smaller than the distance between the surface of the touch layer 32 on the side closer to the display panel 31 and the surface of the touch layer 32 on the side farther from the display panel 31. In this case, when wiring such as data lines and gate lines in the display panel 31 are formed by sequential etching, the first bonding pad 36 and the second bonding pad 37 can be formed by simultaneous etching. That is, the first bonding pad 36 and the second bonding pad 37 include a plurality of stacked metal layers. The thickness of the stacked metal layers is smaller than the distance between the surface of the touch layer 32 on the side closer to the display panel 31 and the surface of the touch layer 32 on the side farther from the display panel 31. Here, the touch layer 32 may be provided directly on the light emission side of the display panel 31, that is, the touch layer 32 and the display panel 31 may be integrally formed.

[0226] Some embodiments of the present disclosure further provide a display device 100. As shown in Figures 1 and 2, the display device 100 includes a display panel 31, a touch layer 32 provided on a light-emitting surface of the display panel 31, and a flexible printed circuit board 4 bonded to the display panel 31.

[0227] The display panel 31 has a display area A1 and a peripheral area A2 located on at least one side of the display area, and a bonding section including a plurality of first bonding pads 36 (see FIG. 7) and a plurality of second bonding pads 37 (see FIG. 7) is provided in the peripheral area A2. The touch layer 32 includes a plurality of first touch leads 321 and a plurality of second touch leads 322, and one first touch lead 321 is electrically connected to one first bonding pad 36, and one second touch lead 322 is electrically connected to one second bonding pad 37.

[0228] The flexible printed board 4 includes a main flexible printed board 43 and a bridge flexible printed board 44 .The main flexible printed circuit board 43 includes a first substrate 410, a plurality of pads P, a touch chip 4100, a plurality of first touch connection lines 41A, a plurality of second touch connection lines 42A, and a plurality of third touch connection lines 30A. The first substrate 410 has a first welding area 410A, a second welding area 410B, and a bonding area. A plurality of first bonding pins 4101 (see FIG. 5) and a plurality of second bonding pins 4102 (see FIG. 5) are provided in the bonding area. One first bonding pin 4101 is electrically connected to one first bonding pad 36, and one second bonding pin 4102 is electrically connected to one second bonding pad 37. A plurality of pads P are provided in the first welding area 410A and the second welding area 410B. The touch chip 4100 is provided on the first substrate 410, and the minimum distance between the touch chip 4100 and the first welding area 410A is smaller than the minimum distance between the touch chip 4100 and the second welding area 410B. A plurality of first touch connection lines 41A are provided on the first substrate 410, and each of the first touch connection lines 41A is electrically connected to the touch chip 4100 at one end and electrically connected to the first touch lead line 321 via the first bonding pin 4101 and the first bonding pad 36 at the other end. A plurality of second touch connection lines 42A are provided on the first substrate 410, and each of the second touch connection lines 42A is electrically connected to one pad P of the second welding area 410B at one end and electrically connected to the second touch lead line 322 via the second bonding pin 4102 and the second bonding pad 37 at the other end. A plurality of third touch connection lines 30A are provided on the first substrate 410, and each of the third touch connection lines 30A has one end electrically connected to one pad P of the first welding area 410A and the other end electrically connected to the touch chip 4100.

[0229] 5 and 6, the bridge flexible printed circuit board 44 includes a second substrate 420, a plurality of pads P, and a plurality of touch conversion lines 420C. The second substrate 420 has a third welding region 420A and a fourth welding region 420B. The plurality of pads P are provided in the third welding region 420A and the fourth welding region 420B, and one pad P in the third welding region 420A is welded to one pad P in the first welding region 410A, and one pad P in the fourth welding region 420B is welded to one pad P in the second welding region 410B. The plurality of touch conversion lines 420C are provided on the second substrate 420, and each of the touch conversion lines 420C is electrically connected at one end to one pad P in the third welding region 420A and electrically connected at the other end to one pad P in the fourth welding region 420B.

[0230] The maximum radial size of the pad P is 1.0 mm or less.

[0231] The third welding area 420A or the fourth welding area 420B includes M rows of pads P, where M≧2. At least 2M pads P are distributed between the two outermost touch conversion lines 420C among the multiple touch conversion lines 420C.

[0232] The pads P in the first welding area 410A, the second welding area 410B, the third welding area 420A, and the fourth welding area 420B are all arranged in a plurality of rows, and at least one row of pads P includes a plurality of pads P. The pads P in two adjacent rows are offset from each other along the column direction.

[0233] 6 and 27, the pad on the bridge flexible printed circuit board 44 is a via pad. The via pad includes two solder lugs 422 and a conductive connection layer 423. The two solder lugs 422 are provided on a surface of the second substrate 420 close to the main flexible printed circuit board 43 and a surface away from the main flexible printed circuit board 43, respectively. A via 421 corresponding to the via pad penetrates the second substrate 420 between the two solder lugs 422 of the via pad and the two solder lugs 422. The conductive connection layer 423 covers the sidewall of the via 421 and both ends are electrically connected to the two solder lugs 422, respectively.

[0234] The display device according to the embodiments of the present disclosure has the same technical features and beneficial effects as the display device according to the above-mentioned embodiments, and the above-mentioned embodiments can be referred to, so the description thereof will be omitted here.

[0235] In some embodiments, referring to FIG. 4, the flexible printed circuit board 4 includes a plurality of data signal control lines. The display panel 31 includes a plurality of data lines Data and a driver chip 4200. The driver chip 4200 is disposed in the peripheral area A2 and is electrically connected to the plurality of data signal control lines and the plurality of data lines Data. The driver chip 4200 is disposed to process signals on the plurality of data signal control lines and output them to the plurality of data lines Data. The number of data signal control lines is less than the number of data lines Data, and the line width of the data signal control lines is wider than the line width of the data lines Data.

[0236] In some embodiments, the number of first touch leads 321 included in the touch layer 32 is the same as the number of first touch connection lines 41A included in the main flexible printed circuit board 43. The number of second touch leads 322 included in the touch layer 32 is the same as the number of second touch connection lines 42A included in the main flexible printed circuit board 43 and the number of third touch connection lines 30A.

[0237] 4 and 8, in some embodiments, the range of the maximum size L1 of the main flexible printed circuit board 4 along the first direction X is 55.25 mm≦L1≦55.55 mm. The first direction X is approximately parallel to the extension direction of the side of the main flexible printed circuit board 43 close to the display panel 31. Further, referring to FIG. 21, the bonding region is strip-shaped and extends along the first direction X. The first bonding pins 4101 and the second bonding pins 4102 are arranged side by side along the first direction X. The first bonding pins 4101 and the second bonding pins 4102 of the main flexible printed circuit board 43 that are furthest apart along the first direction X are arranged side by side along the first direction X. Distance The range of the distance L2 is 53.55 mm≦L2≦53.85 mm. The range of the maximum size L3 of the bonding region along the second direction Y is 1.2 mm≦L3≦1.6 mm. The second direction Y is approximately perpendicular to the first direction X.

[0238] Other structural features and beneficial effects of the display device according to the embodiments of the present disclosure can be explained with reference to the examples in the above embodiments, and the explanation thereof will be omitted here.

[0239] Some embodiments of the present disclosure further provide a manufacturing method for the display device 100 according to any one of the above-described embodiments. Here, as shown in Fig. 31, the manufacturing method includes S10 to S14.

[0240] In S10, the main flexible printed circuit board 43 is formed.

[0241] The main flexible printed circuit board 43 includes a first substrate 410, a plurality of pads P provided in a first welding region 410A and a second welding region 410B of the first substrate 410, a touch chip 4100 provided on the first substrate 410, a plurality of first touch connection lines 41A, a plurality of second touch connection lines 42A, a plurality of third touch connection lines 30A, a plurality of first bonding pins 4101, and a plurality of second bonding pins 4102. One end of each of the first touch connection lines 41A is electrically connected to the touch chip 4100, and the other end is electrically connected to one of the first bonding pins 4101. One end of each of the second touch connection lines 42A is electrically connected to one of the pads P in the second welding region 410B, and the other end is electrically connected to one of the second bonding pins 4102. Each of the third touch connection lines 30A is electrically connected to one pad P of the first welding area 410A at one end and electrically connected to the touch chip 4100 at the other end.

[0242] In S11, the bridge flexible printed circuit board 44 is formed.

[0243] The bridge flexible printed circuit board 44 includes a second substrate 420, a plurality of pads P provided in a third welding area 420A and a fourth welding area 420B of the second substrate 420, and a plurality of touch conversion lines 420C. One end of each of the touch conversion lines 420C is electrically connected to one pad P in the third welding area 420A, and the other end is electrically connected to one pad P in the fourth welding area 420B.

[0244] In S12, a plurality of pads P in the first welding area 410A are welded to corresponding pads P in the third welding area 420A, and a plurality of pads P in the second welding area 410B are welded to corresponding pads P in the fourth welding area 420B to obtain a flexible printed circuit board 4.

[0245] In S13, a display panel 31 and a touch layer 32 are formed. The touch layer 32 is located on one side of the light-emitting surface of the display panel 31. The display panel 31 includes a plurality of first bonding pads 36 and a plurality of second bonding pads 37. The touch layer 32 includes a plurality of first touch leads 321 and a plurality of second touch leads 322. Each of the first touch leads 321 is electrically connected to one of the first bonding pads 36 of the display panel 31. Each of the second touch leads 322 is electrically connected to one of the second bonding pads 37 of the display panel 31.

[0246] Here, the touch layer 32 may be formed on the display panel 31 by a continuous process, that is, after the display panel 31 is formed, the touch layer 32 may be directly formed above the display panel 31, so that the thickness of the touch display panel 3 is relatively small, which is advantageous for making the display device lighter and thinner.

[0247] In S14, the display panel 31 provided with the touch layer 32 is bonded to the flexible printed circuit board 4 so that the multiple first bonding pads 36 correspond to and electrically connect the multiple first bonding pins 4101, and the multiple second bonding pads 37 correspond to and electrically connect the multiple second bonding pins 4102.

[0248] The beneficial effects of the manufacturing method of the display device 100 according to some embodiments of the present disclosure include the above-mentioned embodiments. Display device 100 The beneficial effects are similar to those of the above, and the description thereof will be omitted here.

[0249] In some embodiments, as shown in FIG. 32, the above-mentioned S10 includes S100 and S101.

[0250] In S100, a first conductive layer is formed on the surface of the first substrate 410 and the first conductive layer is patterned so as to form a plurality of pads P in the first welding area 410A and the second welding area 410B.

[0251] For example, a first conductive layer is formed on the surface of the first substrate 410 by coating or chemical deposition, and the first conductive layer is subjected to a mask exposure, development and etching process to form a plurality of pads P in the first welding area 410A and the second welding area 410B. Here, the first conductive layer may be a copper foil.

[0252] Here, the patterned first conductive layer may further form a plurality of wirings, which may include at least one of the first touch connection line 41A, the second touch connection line 42A, the third touch connection line 30A, the first shield connection line 41B, the second shield connection line 42B, the third shield connection line 30B, the ELVDD line, the ELVSS line, the DVDD line, and the high-frequency signal line 48.

[0253] It should be noted that the first substrate 410 includes two surfaces. Forming a first conductive layer on a surface of the first substrate 410 may mean forming a first conductive layer only on one surface of the first substrate 410, or may mean forming a first conductive layer on both opposing surfaces of the first substrate 410. When the main flexible printed circuit board 4 is a two-layer substrate, the first conductive layer is formed on both surfaces of the first substrate 410. When the main flexible printed circuit board 4 is a single-layer substrate, the first conductive layer is formed on one surface of the first substrate 410.

[0254] In S101, a first metal pattern is formed on the surfaces of the pads P, the first metal pattern being arranged to prevent the pads P from being oxidized.

[0255] Here, the formation of the first metal pattern includes nickel plating or electroless nickel / immersion gold (ENIG) method. Based on this, nickel plating includes electrolytic and chemical methods, namely electrolytic nickel plating and chemical nickel plating. Electrolytic nickel plating is a process in which a direct current is passed through an electrolyte solution consisting of nickel salt (referred to as main salt), conductive salt, pH buffer, and wetting agent to deposit a uniform and dense nickel plating layer on a cathode (the object to be plated), where the electrolyte solution contains metallic nickel as the anode and the cathode as the object to be plated. The plating solution with brightener added produces bright nickel, while the electrolyte solution without brightener added produces black nickel. Chemical plating is also called electroless plating and autocatalytic plating. The specific process is a process in which metal ions in an aqueous solution are reduced by a reducing agent under certain conditions and precipitate on the surface of a solid substrate.

[0256] ENIG is electroless gold plating, which does not require an external power source, and forms a gold plating layer while reducing gold ions on the surface of the first substrate 410 through a chemical reduction reaction using only the plating solution.

[0257] In some embodiments, as shown in FIG. 33, the above-mentioned S11 includes S102 to S105.

[0258] In S102, the third welding area 420A and the fourth welding area 420B Pair A second conductive layer is formed on opposite surfaces of the second substrate 420 and the second conductive layer is patterned to form a plurality of solder lugs 422 .

[0259] For example, a second conductive layer is formed on the surface of the second substrate 420 by coating or chemical deposition, and the second conductive layer is subjected to a mask exposure, development and etching process to form a plurality of pads P in the third welding area 420A and the fourth welding area 420B. Here, the second conductive layer may be a copper foil.

[0260] Here, the patterned second conductive layer may further form a plurality of wirings, which may include one or a combination of two of the touch conversion line 420C and the shield conversion line 420D.

[0261] In S103, a second metal pattern 15 is formed on the surfaces of the plurality of solder lugs 422 on both opposing surfaces of the second substrate 420, the second metal pattern 15 being arranged to prevent the plurality of solder lugs 422 from being oxidized.

[0262] The method for forming the second metal pattern 15 is the same as the method for forming the first metal pattern, and the method for forming the first metal pattern may be referred to, and the description thereof will be omitted here.

[0263] In S104, Each At the positions of two solder lugs 422 facing each other along the thickness direction of second substrate 420, two solder lugs 422 and vias 421 penetrating second substrate 420 between the two solder lugs 422 are formed.

[0264] Here, the vias can be formed by a method such as laser drilling or punch drilling.

[0265] In S105, a conductive connection layer 423 is formed on the sidewall of the via 421. Both ends of the conductive connection layer 423 are electrically connected to the two solder lugs 422, respectively. The conductive connection layer 423 includes a conductive layer and a metal layer, which are sequentially stacked. The metal layer is arranged to prevent the conductive layer from being oxidized.

[0266] Here, the order of steps S102 to S105 is not limited. Illustratively, after forming the vias 421 in the second substrate 420, a second conductive layer is formed on the surfaces of both opposing sides of the second substrate 420, and a conductive connection layer 423 is formed on the side walls of the vias 421. In this case, the third welding area 420A and the fourth welding area 420B each include a plurality of pads P, and a second metal pattern 15 is formed on the surface of the pads P, and a metal layer is formed on the side walls of the vias 421. The order of steps S102 to S105 in some embodiments of the present disclosure includes, but is not limited to, the above-mentioned embodiments, and any other different order is included in the scope of protection of some embodiments of the present disclosure, and the description thereof is omitted here.

[0267] A method for forming the conductive connection layer 423 can be, for example, depositing copper foil on the wall of the via 421. A method for forming a metal layer can be, for example, nickel plating or ENIG treatment on the conductive connection layer 423 on the wall of the via.

[0268] In some embodiments, as shown in FIG. 34, the method for manufacturing the display device 100 further includes S106 and S107.

[0269] In S106, green oil is applied to the first welding area 410A, the second welding area 410B, the third welding area 420A, the fourth welding area 420B and the element area 45; the green oil is removed from the areas of the first welding area 410A, the second welding area 410B, the third welding area 420A and the fourth welding area 420B where the multiple pads P are provided so as to expose the multiple pads P; and the green oil is removed from the areas of the element area 45 where the elements are provided so as to expose each element.

[0270] In S107, a resin material is applied to the areas other than the first welding area 410A, the second welding area 420A, the third welding area 420A, the fourth welding area 420B and the element area 45.

[0271] The "resin material" may be one or a combination of two of a polyimide film and a polyester resin.

[0272] The order of steps S106 and S107 is not limited. Step S106 may be performed first, and then step S107; step S107 may be performed first, and then step S106.

[0273] In some embodiments, as shown in FIG. 35, the above-mentioned S12 includes S110 to S112.

[0274] In S110, solder paste is applied to a plurality of pads P in the first welding area 410A and the second welding area 410B.

[0275] Please refer to FIG. 36, which is a structural diagram of a case where solder paste is applied onto the pad P of the first welding region 410A.

[0276] In S111, the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 are aligned and attached to each other. The pads P in the first welding area 410A are attached to the pads P in the third welding area 420A in correspondence with each other, and the pads P in the second welding area 410B are attached to the pads P in the fourth welding area 420B in correspondence with each other.

[0277] In some embodiments, the "alignment" may be a contour alignment, which is a one-to-one correspondence between the pads P of the first welding area 410A and the pads P of the third welding area 420A; and a one-to-one correspondence between the pads P of the second welding area 410B and the pads P of the fourth welding area 420B.

[0278] In some other examples, the "alignment" may be the alignment of marks, which is to provide marks at corresponding positions of the first welding area 410A and the third welding area 420A, and provide marks at corresponding positions of the second welding area 410B and the fourth welding area 420B, for example, to provide an "X-shape" and align the corresponding marks.

[0279] In S112, the attached main flexible printed circuit board 43 and bridge flexible printed circuit board 44 are heated so as to melt the solder paste.

[0280] The attached main flexible printed circuit board 43 and bridge Flexible Printed Circuit Board 44 The solder paste can be placed in a boiler and heated. In this case, the heating temperature can be the melting point of the solder paste (183° C.). In some embodiments, the heating temperature is 200° C. or higher.

[0281] Based on this, since the pads P in the third welding area 420A and the fourth welding area 420B are via pads, when the solder paste is in a molten state, the vias can be completely filled with the solder paste, as shown in FIG. 37, which is a diagram showing an X-section (cross-sectional view) of FIG. 36, and the via pads are sufficiently filled with solder, i.e., 100% filled with solder.

[0282] As shown in FIG. 37, FIG. 37 shows an enlarged schematic view of six welding points after the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 are welded together.

[0283] As an example, the six welding points are: From top to bottom and From left to right, this may be a first weld point, a second weld point, a third weld point, a fourth weld point, a fifth weld point, and a sixth weld point.

[0284] As can be seen from FIG. 37, a certain amount of solder overflows at the top of the first, second, fourth, and fifth welding points, and the thickness of the overflowed solder at the top of the first, second, fourth, and fifth welding points is not completely the same. The thickness of the overflowed solder at the top of the third and sixth welding points is very small and is almost the same as the thickness of the conductive thin film (copper foil). For example, the thickness of the overflowed solder at the top of the first, second, third, fourth, fifth, and sixth welding points is 0.05 mm or less.

[0285] 37 again, the solder overflow shapes at the top ends of the first, second, third, fourth, fifth and sixth welding points are different. For example, the solder overflow shapes at the top ends of the first, second, fourth and fifth welding points are arc-shaped, while the solder overflow shapes at the top ends of the third and sixth welding points are linear.

[0286] As can be seen by looking again at FIG. 37, the bridge flexible printed circuit board 44 and the main flexible printed circuit board 43 After welding, at the same welding point (see, for example, the third welding point, the fourth welding point, and the fifth welding point), two pads P that are welded together are Different positions of The spacing between the solder pads is different. Illustratively, the solder thickness on the left is greater than the solder thickness on the right.

[0287] Also, as is clear from the first weld point, the second weld point, the third weld point, the fourth weld point, the fifth weld point, and the sixth weld point, the width of the central solder of the two pads P welded together changes from wide to narrow to wide from top to bottom. For example, shapes like ">" and "<" appear on both the left and right sides of the central solder.

[0288] As an example ,figure 38 indicates that there are other structures and wirings around the position of one of the welding points. Also, at the position of the welding point shown in Fig. 38, the thickness A2 of the solder in the via pad is 123.4 µm; the distance A3 between the right solder and the lower surface (surface away from the main flexible printed board 43) of the bridge flexible printed board 44 is 19.9 µm; the distance A1 between the left solder and the lower surface (surface away from the main flexible printed board 43) of the bridge flexible printed board 44 is 34.3 µm; and the distance A4 between the right solder and the upper surface (surface close to the main flexible printed board 43) of the bridge flexible printed board 44 is 53.3 µm.

[0289] In some embodiments, as shown in FIG. 39, the above-mentioned S111 includes S1110 to S1115.

[0290] In S1110, the main flexible printed circuit board 43 No. 1 A first image including an alignment mark and a bridge flexible printed circuit board 44 Second A second image is captured that includes the alignment marks.

[0291] In S1111, the first image and the second image are processed to obtain the coordinates of the first alignment mark of the main flexible printed circuit board 43 and the coordinates of the second alignment mark of the bridge flexible printed circuit board 44.

[0292] Here, the main flexible printed circuit board 43 No. 1 The coordinates of the alignment marks and the bridge flexible printed circuit board 44 Second The coordinates of the alignment marks are three-dimensional spatial coordinates, i.e., the coordinates are expressed as (X, Y, Z).

[0293] In S1112, the robot arm is controlled to move the bridge flexible printed circuit board 44 and / or the main flexible printed circuit board 43 based on the coordinates of the first alignment mark and the coordinates of the second alignment mark so as to align the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44.

[0294] Controlling the robot arm to move the bridge flexible printed circuit board 44 and / or the main flexible printed circuit board 43 may mean controlling the robot arm to move the bridge flexible printed circuit board 44 and the main flexible printed circuit board 43, or may mean controlling the robot arm to move only the main flexible printed circuit board 43, or may mean controlling the robot arm to move only the bridge flexible printed circuit board 44.

[0295] In S1113, a third image including the alignment mark of the aligned main flexible printed circuit board 43 and a fourth image including the alignment mark of the aligned bridge flexible printed circuit board 44 are collected.

[0296] In S1114, it is detected whether or not the relative position between the aligned main flexible printed board 43 and bridge flexible printed board 44 is within a preset error range.

[0297] Here, if the relative positions of the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 are within a preset error range, step S1115 is executed. If the relative positions of the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 are not within the preset error range, the above steps S1110 to S1114 are repeatedly executed until the aligned main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 are finally brought within the preset error range, i.e., completely correspond to each other.

[0298] In S1115, the bridge flexible printed circuit board 44 and the main flexible printed circuit board 43 are attached to each other with an adhesive layer.

[0299] Here, the adhesive layer may be a solid adhesive or a liquid adhesive, and the solid adhesive may be, for example, at least one of a pressure sensitive adhesive (PSA), an epoxy adhesive, and an acrylic adhesive. If the adhesive layer is a liquid adhesive, the bridge flexible printed circuit board 44 and the main flexible printed circuit board 43 can be attached to each other by a dispenser method.

[0300] In addition, in order to prevent the main flexible printed board 43 and the bridge flexible printed board 44 from moving when they are placed in a boiler to be heated after being aligned and attached, the main flexible printed board 43 and the bridge flexible printed board 44 are attached to each other with an adhesive layer before being aligned, thereby avoiding the occurrence of misalignment between the aligned main flexible printed board 43 and the bridge flexible printed board 44.

[0301] In the above-mentioned S1110 to S1113, the method of collecting and processing the first image and the second image, the method of collecting the third image and the fourth image, and the method of detecting whether the aligned main flexible printed board 43 and the bridge flexible printed board 44 are within a preset error range are not limited. Exemplarily, the first image, the second image, the third image, and the fourth image can be captured using a camera, and the first image and the second image can be processed by a processor (for example, the coordinates of the first alignment mark and the coordinates of the second alignment mark can be obtained by computer simulation); and the third image and the fourth image can be processed by the processor to detect whether the aligned main flexible printed board 43 and the bridge flexible printed board 44 are within a preset error range.

[0302] In the embodiment of the present disclosure, when manufacturing the flexible printed circuit board 4, the main flexible printed circuit board 43 and the bridge flexible printed circuit board 44 are welded to each other by a welding method, and a fully automated method is adopted in the process of manufacturing the flexible printed circuit board 4, so that the manufacturing efficiency can be greatly improved, and the structure of the formed flexible printed circuit board 4 is lighter, thinner, and simpler.

[0303] The above are only specific embodiments of the present disclosure, but the scope of protection of the present disclosure is not limited thereto, and any modifications or replacements that can be easily conceived by any person skilled in the art within the technical scope of the present disclosure are all included within the technical scope of the present disclosure. Therefore, the scope of protection of the present disclosure shall be governed by the scope of protection described in the claims.

[0304] This application claims priority from Chinese patent application having application number 202010113081.1 filed on February 24, 2020, and Chinese patent application having application number 202010508043.6 filed on June 5, 2020, the entire contents of which are incorporated herein by reference.

Claims

1. A display device, comprising: A display panel; a touch layer provided on a light exit surface of the display panel, the touch layer including a plurality of first touch leads and a plurality of second touch leads; a flexible printed circuit board bonded to the display panel, the flexible printed circuit board including a main flexible printed circuit board and a bridge flexible printed circuit board; The main flexible printed circuit board is a first substrate having a first welding area, a second welding area, and a bonding area, where the bonding area is an area of ​​the first substrate bonded to the display panel; a plurality of pads disposed in the first welding area and the second welding area; a touch tip provided on the first substrate, where a minimum distance between the touch tip and the first welding area is smaller than a minimum distance between the touch tip and the second welding area; a plurality of first touch connection lines provided on the first substrate, where each first touch connection line has one end electrically connected to the touch chip and another end electrically connected to a corresponding one of the plurality of first touch lead lines in the touch layer; a plurality of second touch connection lines provided on the first substrate, where each second touch connection line has one end electrically connected to a corresponding one of the pads of the second welding area and another end electrically connected to a corresponding one of the plurality of second touch lead lines in the touch layer; a plurality of third touch connection lines provided on the first substrate, where each third touch connection line has one end electrically connected to a corresponding pad of the first welding area and another end electrically connected to the touch chip; The bridge flexible printed circuit board is a second substrate having a third weld area and a fourth weld area; a plurality of pads provided in the third welding area and the fourth welding area, where one pad in the third welding area is welded to a corresponding one pad in the first welding area, and one pad in the fourth welding area is welded to a corresponding one pad in the second welding area; a plurality of touch conversion lines provided on the second substrate, where each touch conversion line has one end electrically connected to a corresponding pad of the third welding area and another end electrically connected to a corresponding pad of the fourth welding area; A display device, wherein the maximum radial size of any one of the pads is 1.0 mm or less.

2. The bridge flexible printed circuit board is 2. The display device of claim 1, further comprising at least one shield conversion line provided on the second substrate, each shield conversion line having one end electrically connected to a corresponding one of the pads in the third welding region and another end electrically connected to a corresponding one of the pads in the fourth welding region.

3. 3. The display device according to claim 2, wherein the bridge flexible printed circuit board includes a plurality of the shield conversion lines, the plurality of the shield conversion lines include at least two edge shield conversion lines located on the outermost sides, and among the two edge shield conversion lines, both ends of one edge shield conversion line and both ends of the other edge shield conversion line are sequentially connected to form a ring, and the plurality of touch conversion lines are all provided inside the ring.

4. the third welding area and the fourth welding area each have M rows of pads, where M>2; Of the two edge shield conversion lines, both ends of one edge shield conversion line are located on a side away from the pads in the last row of pads in the first row of pads in the third welding area and a side away from the pads in the last row of pads in the first row of pads in the fourth welding area, and are electrically connected to the two pads that are the furthest apart among the pads in the first row of pads in the third welding area and the pads in the first row of pads in the fourth welding area; both ends of the other edge shield conversion line are located on a side away from the pads in the first row of pads in the last row of pads in the third welding area and a side away from the pads in the first row of pads in the last row of pads in the fourth welding area, and are electrically connected to the two pads that are the furthest apart among the pads in the last row of pads in the third welding area and the pads in the last row of pads in the fourth welding area, a pad in a first row of pads in the third welding region that is electrically connected to the one edge shield conversion line and a pad in a last row of pads in the third welding region that is electrically connected to the other edge shield conversion line are electrically connected to each other; 4. The display device of claim 3, wherein a pad in a first row of pads in the fourth welding region that is electrically connected to one of the edge shield conversion lines is electrically connected to a pad in a last row of pads in the fourth welding region that is electrically connected to another of the edge shield conversion lines.

5. A display device as described in any one of claims 1 to 4, wherein the third welding area and the fourth welding area are provided on opposite ends of the second substrate, and the orthogonal projection of the second substrate on the main flexible printed circuit board is not a centrally symmetric figure.

6. The display device according to any one of claims 2 to 5, wherein the third welding area and the fourth welding area are both provided with M rows of pads, where M≧2; at least 2M pads are distributed between two outermost conversion lines among the plurality of conversion lines on the second substrate, and the plurality of conversion lines include the plurality of touch conversion lines and the at least one shield conversion line.

7. A display device as described in any one of claims 2 to 6, wherein the first welding area and the second welding area are arranged side by side along a first direction; the first direction is approximately parallel to an extension direction of a side edge of the main flexible printed circuit board that is closer to the display panel.

8. The pads in the third welding area and the pads in the fourth welding area are both arranged in a plurality of rows, and at least one of the rows of pads in the third welding area includes a plurality of pads arranged along the first direction, and at least one of the rows of pads in the fourth welding area includes a plurality of pads arranged along the first direction; 8. The display device of claim 7, wherein at least one of the plurality of conversion lines on the second substrate passes through an area of ​​the third welding area and the fourth welding area other than an area between a first row of pads and a last row of pads to be electrically connected to a corresponding pad, and the plurality of conversion lines include the plurality of touch conversion lines and the at least one shield conversion line.

9. 9. The display device of claim 8, wherein the pads in two adjacent rows are offset from each other along a second direction; the second direction is substantially perpendicular to the first direction.

10. the second substrate has a transition wiring region and a connection sector region located at opposite ends of the transition wiring region, the transition wiring region and the connection sector region being located between the third welding region and the fourth welding region; Each of the plurality of conversion lines including the plurality of touch conversion lines and the at least one shield conversion line includes a transition segment and a connection segment located at opposite ends of the transition segment, the transition segment extending along the first direction and disposed in the transition wiring region, and the connection segment disposed in the connection sector region; A display device as described in any one of claims 7 to 9, wherein the minimum width of the connection sector region in the second direction is greater than or equal to the width of the transition wiring region in the second direction, and the second direction is approximately perpendicular to the first direction.

11. The width of the transition wiring region in the second direction is smaller than the maximum width of the third welding region in the second direction; and / or the width of the transition wiring region in the second direction is smaller than the maximum width of the fourth welding region in the second direction; 11. The display device of claim 10, wherein a portion of the connection sector area close to the third welding area has a maximum width in the second direction that is greater than a maximum width of the third welding area in the second direction; and / or a portion of the connection sector area close to the fourth welding area has a maximum width in the second direction that is greater than a maximum width of the fourth welding area in the second direction.

12. A display device according to any one of the preceding claims, wherein the outer contour of the pad is substantially circular.

13. The display device according to claim 12, wherein the diameter of the pads is in the range of 0.25 mm to 0.35 mm.

14. the pads on the second substrate are via pads; the second substrate has a plurality of vias, each via corresponding to one via pad; The via pad is two solder lugs provided on a surface of the second substrate close to the main flexible printed circuit board and a surface of the second substrate away from the main flexible printed circuit board, respectively, wherein a via corresponding to the via pad penetrates the second substrate between the two solder lugs of the via pad and the two solder lugs; The display device according to any one of claims 1 to 13, further comprising: a conductive connection layer covering a sidewall of the via corresponding to the via pad, the both ends of which are electrically connected to the two solder lugs, respectively.

15. The display device according to claim 14 , wherein an outer contour of the via pad in an orthogonal projection on the second substrate is substantially circular.

16. The display device according to claim 15, wherein the diameter of the outer contour of the via pad is in the range of 0.25 mm to 0.35 mm.

17. The display device according to any one of claims 14 to 16, wherein an inner contour of the via pad in an orthogonal projection on the second substrate is substantially circular or X-shaped.

18. When the inner contour of the via pad in the orthogonal projection on the second substrate is circular, the diameter of the inner contour is in the range of 0.05 mm to 0.15 mm; The display device according to claim 17, wherein when an inner contour of the orthogonal projection of the via pad on the second substrate is X-shaped, a diameter of a circumscribed circle corresponding to the inner contour is in the range of 0.05 mm to 0.2 mm.

19. The main flexible printed circuit board further includes: a first metal pattern arranged to cover pads on the first substrate and to prevent the pads on the first substrate from being oxidized; and / or The bridge flexible printed circuit board further includes: A display device as claimed in any preceding claim, comprising a second metal pattern arranged to cover pads on the second substrate and to prevent the pads on the second substrate from being oxidized.

20. When the main flexible printed circuit board includes a first metal pattern, the material of the first metal pattern includes one or a combination of two of gold and nickel; 20. The display device according to claim 19, wherein when the bridge flexible printed circuit board includes a second metal pattern, a material of the second metal pattern includes one or a combination of two of gold and nickel.

21. The main flexible printed circuit board further includes: a first green oil layer covering at least a first region of the first substrate, wherein the first region is a region of the first welding region and the second welding region other than a region where a pad is provided; a first resin layer covering an area of ​​the first substrate other than the first welding area and an area of ​​the first substrate other than the second welding area; The bridge flexible printed circuit board further includes: a second green oil layer covering at least a second region of the second substrate, wherein the second region is a region of the third welding region and the fourth welding region other than a region where a pad is provided; The display device according to any one of claims 1 to 20, further comprising a second resin layer covering an area of ​​the second substrate other than the third welding area and an area of ​​the second substrate other than the fourth welding area.

22. the first substrate has an element region; The main flexible printed circuit board further includes: At least one element is provided on a side of the first substrate close to the bridge flexible printed circuit board, is located in an element region of the first substrate, and has the touch chip; The display device according to any one of claims 1 to 21, further comprising: a third green oil layer covering an area of ​​the element region other than an area in which the at least one element is provided.

23. The main flexible printed circuit board further includes: The display device according to claim 22 , further comprising a support provided on a side of the first substrate away from the bridge flexible printed circuit board, the element region being within a range of an orthogonal projection of the support on the first substrate.

24. 24. The display device according to claim 23, wherein there is a gap between a boundary of the orthogonal projection of the first substrate of the support and a boundary of the element region, the gap being 0.5 mm or more.

25. The main flexible printed circuit board further includes: a plurality of first bonding pins provided in the bonding region, and at least one first bonding pin is arranged to electrically connect the first touch connection line to a corresponding first touch lead line in a touch layer of the display device; A display device as described in any one of claims 1 to 24, comprising: a plurality of second bonding pins provided in the bonding region, and at least one second bonding pin arranged to electrically connect the second touch connection line to a corresponding second touch lead line in the touch layer.

26. The maximum size L of the main flexible printed circuit board along the first direction １ The range is 55.25 mm≦L １ ≦55.55 mm; the first direction is approximately parallel to an extension direction of a side of the main flexible printed circuit board that is closer to the display panel; The bonding region is strip-shaped and extends along the first direction; the first bonding pins and the second bonding pins are arranged in a line along the first direction; and the range of the distance L2 between the first bonding pin and the second bonding pin that are the furthest apart on the main flexible printed circuit board along the first direction is 53.55 mm≦L ２ ≦53.85 mm, The maximum size L3 of the bonding region in the second direction is in the range of 1.2 mm≦L ３ 26. The display device of claim 25, wherein: ≦1.6 mm; and the second direction is substantially perpendicular to the first direction.

27. The number of first touch leads included in the touch layer is the same as the number of first touch connecting lines included in the main flexible printed circuit board; A display device described in any one of claims 1 to 26, wherein the number of second touch lead wires included in the touch layer is the same as the number of second touch connection wires and the number of third touch connection wires included in the main flexible printed circuit board.

28. the main flexible printed circuit board further includes a plurality of data signal control lines provided on the first substrate, The display panel has a display area and a peripheral area located on at least one side of the display area, A plurality of data lines; a driver chip disposed in the peripheral region and electrically connected to the plurality of data signal control lines and the plurality of data lines, where the driver chip is configured to process signals on the plurality of data signal control lines and output them to the plurality of data lines; The display device according to any one of claims 1 to 27.

29. 29. The display device according to claim 28, wherein the number of data signal control lines included in the main flexible printed circuit board is smaller than the number of data lines included in the display panel, and the line width of the data signal control lines is wider than the line width of the data lines.

30. The main flexible printed circuit board further includes a first bonding pin and a second bonding pin, The display panel further comprises: a plurality of first bonding pads, where one first bonding pad is electrically connected to a corresponding one of the first bonding pins and a corresponding one of the first touch leads; A display device as claimed in any one of claims 1 to 29, comprising: a plurality of second bonding pads, wherein one second bonding pad is electrically connected to a corresponding one of the second bonding pins and a corresponding one of the second touch lead wires.

31. The display device of claim 30 , wherein a thickness of the first bonding pad and a thickness of the second bonding pad are both smaller than the distance between a surface of the touch layer closer to the display panel and a surface of the display panel away from the touch layer.

32. A display device, comprising: a display panel, a touch layer provided on a light exit surface of the display panel, and a flexible printed circuit board bonded to the display panel, the display panel having a display area and a peripheral area located on at least one side of the display area, the peripheral area being provided with a bonding part including a plurality of first bonding pads and a plurality of second bonding pads; The touch layer includes a plurality of first touch leads and a plurality of second touch leads, each of which is electrically connected to a corresponding one of the first bonding pads, and each of which is electrically connected to a corresponding one of the second bonding pads, and The flexible printed circuit board includes a main flexible printed circuit board and a bridge flexible printed circuit board, The main flexible printed circuit board is a first substrate having a first welding area, a second welding area, and a bonding area, a plurality of first bonding pins and a plurality of second bonding pins provided in the bonding area, one first bonding pin electrically connected to a corresponding one first bonding pad, and one second bonding pin electrically connected to a corresponding one second bonding pad; a plurality of pads disposed in the first welding area and the second welding area; a touch tip provided on the first substrate, where a minimum distance between the touch tip and the first welding area is smaller than a minimum distance between the touch tip and the second welding area; a plurality of first touch connecting lines provided on the first substrate, where each first touch connecting line has one end electrically connected to the touch chip and another end electrically connected to a corresponding first touch lead line via the first bonding pin and the first bonding pad; a plurality of second touch connection lines provided on the first substrate, where each second touch connection line has one end electrically connected to a corresponding pad of the second welding area and the other end electrically connected to a corresponding second touch lead line via the second bonding pin and the second bonding pad; a plurality of third touch connection lines provided on the first substrate, where each third touch connection line has one end electrically connected to a corresponding pad of the first welding area and another end electrically connected to the touch chip; The bridge flexible printed circuit board is a second substrate having a third weld area and a fourth weld area; a plurality of pads provided in the third welding area and the fourth welding area, where one pad in the third welding area is welded to a corresponding one pad in the first welding area, and one pad in the fourth welding area is welded to a corresponding one pad in the second welding area; a plurality of touch conversion lines provided on the second substrate, where each touch conversion line has one end electrically connected to a corresponding pad of the third welding area and another end electrically connected to a corresponding pad of the fourth welding area; The maximum radial size of any one pad is 1.0 mm or less; The third welding area and the fourth welding area are each provided with M rows of pads, where M≧2; at least 2M pads are distributed between two outermost touch conversion lines among the plurality of touch conversion lines; the pads in the first welding area, the second welding area, the third welding area, and the fourth welding area are all arranged in a plurality of rows, at least one of the rows of pads in the third welding area includes a plurality of pads, and at least one of the rows of pads in the fourth welding area includes a plurality of pads; two adjacent rows of pads are offset from each other along a second direction, the second direction being approximately perpendicular to an extension direction of a side edge of the main flexible printed circuit board close to the display panel; A display device comprising: a pad on the bridge flexible printed circuit board is a via pad; a second substrate has a plurality of vias, each of which corresponds to one via pad; the via pad includes two solder lugs and a conductive connection layer, the two solder lugs being respectively provided on a surface of the second substrate close to the main flexible printed circuit board and a surface away from the main flexible printed circuit board, and a via corresponding to the via pad penetrates the second substrate between the two solder lugs of the via pad and through the two solder lugs; the conductive connection layer covers a sidewall of the via corresponding to the via pad, and both ends are electrically connected to the two solder lugs respectively.

33. the flexible printed circuit board includes a plurality of data signal control lines; The display panel includes: A plurality of data lines; a driver chip disposed in the peripheral region and electrically connected to the plurality of data signal control lines and the plurality of data lines, where the driver chip is configured to process signals on the plurality of data signal control lines and output the signals to the plurality of data lines; the number of the data signal control lines is smaller than the number of the data lines, and the line width of the data signal control lines is wider than the line width of the data lines; The display device according to claim 32.

34. The display device of claim 32 or claim 33, wherein the number of first touch lead wires included in the touch layer is the same as the number of first touch connection wires included in the main flexible printed circuit board; the number of second touch lead wires included in the touch layer is the same as the number of second touch connection wires and the number of third touch connection wires included in the main flexible printed circuit board.

35. The maximum size L of the main flexible printed circuit board along the first direction １ The range is 55.25 mm≦L １ ≦55.55 mm; the first direction is approximately parallel to an extension direction of a side of the main flexible printed circuit board that is closer to the display panel; The bonding region is strip-shaped and extends along the first direction; the first bonding pins and the second bonding pins are arranged in a line along the first direction; and the range of the distance L2 between the first bonding pin and the second bonding pin that are the furthest apart on the main flexible printed circuit board along the first direction is 53.55 mm≦L ２ ≦53.85 mm, The maximum size L3 of the bonding region in the second direction is in the range of 1.2 mm≦L ３ Display device according to any one of claims 32 to 34, wherein the thickness is ≦1.6 mm.

36. A method for manufacturing a display device, comprising the steps of: forming a main flexible printed circuit board including a first substrate, a plurality of pads provided in a first welding area and a second welding area of ​​the first substrate, a touch chip provided on the first substrate, a plurality of first touch connecting lines, a plurality of second touch connecting lines, a plurality of third touch connecting lines, a plurality of first bonding pins and a plurality of second bonding pins, wherein each of the first touch connecting lines has one end electrically connected to the touch chip and another end electrically connected to a corresponding one of the first bonding pins, each of the second touch connecting lines has one end electrically connected to a corresponding one of the pads in the second welding area and another end electrically connected to a corresponding one of the second bonding pins, and each of the third touch connecting lines has one end electrically connected to a corresponding one of the pads in the first welding area and another end electrically connected to the touch chip; forming a bridge flexible printed circuit board including a second substrate, a plurality of pads provided in a third welding area and a fourth welding area of ​​the second substrate, and a plurality of touch conversion lines, wherein one end of each of the touch conversion lines is electrically connected to a corresponding one of the pads in the third welding area and the other end is electrically connected to a corresponding one of the pads in the fourth welding area; welding a plurality of pads in the first welding area to a plurality of pads in the third welding area in correspondence with each other, and welding a plurality of pads in the second welding area to a plurality of pads in the fourth welding area in correspondence with each other, to obtain a flexible printed circuit board; forming a display panel and a touch layer, where the touch layer is located on a light-emitting surface of the display panel, the display panel includes a plurality of first bonding pads and a plurality of second bonding pads, the touch layer includes a plurality of first touch leads and a plurality of second touch leads, each of the first touch leads being electrically connected to a corresponding one of the first bonding pads of the display panel, and each of the second touch leads being electrically connected to a corresponding one of the second bonding pads of the display panel; and bonding a display panel provided with a touch layer to the flexible printed circuit board so as to correspond and electrically connect the plurality of first bonding pads to the plurality of first bonding pins, and to correspond and electrically connect the plurality of second bonding pads to the plurality of second bonding pins.

37. The above-mentioned forming of the main flexible printed circuit board includes: forming a first conductive layer on a surface of the first substrate and patterning the first conductive layer to form a plurality of pads in the first welding area and the second welding area; forming a first metal pattern on a surface of the plurality of pads, the first metal pattern being arranged to protect the plurality of pads from oxidation; The above-mentioned forming of the bridge flexible printed circuit board is forming a second conductive layer on opposing surfaces of a second substrate and patterning the second conductive layer to form a plurality of mating solder lugs in the third welding area and the fourth welding area; forming a second metal pattern on a surface of the plurality of solder lugs on opposite sides of the second substrate, the second metal pattern being arranged to protect the plurality of solder lugs from oxidation; forming vias at positions of two solder lugs facing each other along a thickness direction of each of the second substrates, the vias penetrating the two solder lugs and the second substrate between the two solder lugs; forming a conductive connection layer on a sidewall of the via, where both ends of the conductive connection layer are electrically connected to the two solder lugs respectively, the conductive connection layer including a conductive layer and a metal layer arranged in a sequentially stacked manner, the metal layer being arranged to prevent the conductive layer from being oxidized; A method for manufacturing the display device according to claim 36.

38. Applying green oil to the first welding area, the second welding area and an element area of ​​the first substrate, and the third welding area and the fourth welding area of ​​the second substrate; removing green oil from the first welding region, the second welding region, the third welding region, and the fourth welding region in which a plurality of pads are provided, so as to expose the plurality of pads, and removing green oil from the element region in which elements are provided, so as to expose each element; 38. The method for manufacturing a display device according to claim 36 or 37, further comprising applying a resin material to areas of the first substrate and the second substrate other than the first welding area, the second welding area, the third welding area, the fourth welding area and the element area.

39. The above-mentioned method of welding the plurality of pads in the first welding region to the plurality of pads in the third welding region and welding the plurality of pads in the second welding region to the plurality of pads in the fourth welding region to obtain a flexible printed circuit board includes the steps of: applying solder paste to a plurality of pads in the first weld area and the second weld area; aligning and attaching the main flexible printed circuit board and the bridge flexible printed circuit board, attaching the plurality of pads in the first welding area to the plurality of pads in the third welding area so as to correspond to each other, and attaching the plurality of pads in the second welding area to the plurality of pads in the fourth welding area so as to correspond to each other; A method for manufacturing a display device according to any one of claims 36 to 38, comprising: heating the main flexible printed circuit board and the bridge flexible printed circuit board that are attached together so as to melt the solder paste.

40. The above-mentioned alignment and bonding of the main flexible printed circuit board and the bridge flexible printed circuit board includes: acquiring a first image including a first alignment mark of the main flexible printed circuit board and a second image including a second alignment mark of the bridge flexible printed circuit board; processing the first image and the second image to obtain coordinates of the first alignment mark of the main flexible printed circuit board and coordinates of the second alignment mark of the bridge flexible printed circuit board; controlling a robot arm to move the bridge flexible printed circuit board and / or the main flexible printed circuit board according to the coordinates of the first alignment mark and the coordinates of the second alignment mark so as to align the main flexible printed circuit board and the bridge flexible printed circuit board; acquiring a third image including the alignment marks of the aligned main flexible printed circuit board and a fourth image including the alignment marks of the aligned bridge flexible printed circuit board; Detecting whether the relative position of the aligned main flexible printed circuit board and the aligned bridge flexible printed circuit board is within a preset error range; in response to detecting that the relative position of the main flexible printed circuit board and the bridge flexible printed circuit board is within a preset error range, attaching the main flexible printed circuit board and the bridge flexible printed circuit board to each other with an adhesive layer; 40. The method for manufacturing a display device of claim 39, further comprising: in response to detecting that the relative position of the main flexible printed circuit board and the bridge flexible printed circuit board is not within a preset error range, subsequently adjusting the relative position of the main flexible printed circuit board and the bridge flexible printed circuit board until the relative position of the two is within the preset error range.

Images