Flexible circuit board and display device

Abstract

The embodiment of the utility model provides a flexible circuit board, and belongs to the technical field of display. The flexible circuit board comprises a board body, a first shielding layer, a reinforcing sheet and a connector, the board body is provided with a first surface and a second surface which are opposite, and the board body is provided with a first end and a second end in the length direction of the board body. The connector is located on the first surface and at the first end, and the connector is connected with the board body. The reinforcing sheet is located on the second surface and at the first end. The orthographic projection of the connector on the first surface and the orthographic projection of the reinforcing sheet on the first surface at least partially coincide. The first shielding layer is located on the second surface, and the first shielding layer is electrically connected with the reinforcing sheet. According to the embodiment of the invention, the problem of poor static and electromagnetic protection capability of the back surface of the connector in the flexible circuit board can be improved.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to the field of display technology, and in particular to a flexible circuit board and a display device. Background Art

[0002] Display devices have a wide range of application scenarios in life, such as mobile phones, tablet computers and other electronic devices. Display devices generally include a display panel and an FPC (Flexible Printed Circuit Board). The FPC is connected to the display panel, and the FPC is located on the back of the display panel.

[0003] In the related art, the FPC includes a board body, a first shielding layer, a reinforcing sheet and a connector. The board body has a first surface and a second surface opposite to each other. The board body has a first end and a second end in the length direction of the board body. The connector is located at the first end and on the first surface, and the connector is connected to the board body. The reinforcing sheet is located on the second surface and at the first end, and the orthographic projection of the connector on the first surface at least partially overlaps with the orthographic projection of the reinforcing sheet on the first surface. The first shielding layer is located on the second surface, and the first shielding layer and the reinforcing sheet are arranged at intervals.

[0004] During the use of the display device, the electrostatic and electromagnetic protection capabilities of the back of the connector are relatively poor. Utility Model Content

[0005] The embodiments of the present disclosure provide a flexible circuit board and a display device, which can improve the problem that the electrostatic and electromagnetic protection capabilities of the back of the connector are poor due to the spacing between the first shielding layer and the reinforcing sheet. The technical solution is as follows:

[0006] On the one hand, a flexible circuit board is provided, which includes a board body, a first shielding layer, a reinforcement sheet and a connector, wherein the board body has a first surface and a second surface relative to each other, and the board body has a first end and a second end in the length direction of the board body; the connector is located on the first surface and at the first end, and the connector is connected to the board body; the reinforcement sheet is located on the second surface and at the first end, and the orthographic projection of the connector on the first surface at least partially overlaps with the orthographic projection of the reinforcement sheet on the first surface; the first shielding layer is located on the second surface, and the first shielding layer is electrically connected to the reinforcement sheet.

[0007] Optionally, the flexible circuit board further includes a conductive adhesive, the reinforcing sheet and the board body are connected via the conductive adhesive, and the reinforcing sheet and the first shielding layer are connected via the conductive adhesive.

[0008] Optionally, an orthographic projection of the first shielding layer on the first surface partially overlaps with an orthographic projection of the reinforcing sheet on the first surface.

[0009] Optionally, a ratio of an area of ​​an overlapped region of an orthographic projection of the first shielding layer on the first surface and an orthographic projection of the reinforcing sheet on the first surface to an area of ​​an orthographic projection of the reinforcing sheet on the first surface is greater than or equal to 10%.

[0010] Optionally, the board body includes a first substrate layer and a first routing layer, the first routing layer is located on a side of the first substrate layer away from the first surface, the board body also has a first opening, the first opening is located on the second surface, the orthographic projection of the first opening on the first surface is located within the orthographic projection of the reinforcement plate on the first surface, and the reinforcement plate is electrically connected to the grounding structure in the first routing layer through the first opening.

[0011] Optionally, an orthographic projection of the first shielding layer on the first surface is located on one side of an orthographic projection of the first opening on the first surface.

[0012] Optionally, an orthographic projection of the first shielding layer on the first surface surrounds an orthographic projection of the first opening on the first surface.

[0013] Optionally, an orthographic projection of the first opening on the first surface is located within an orthographic projection of the first shielding layer on the first surface.

[0014] Optionally, in the width direction of the plate, the ratio of the size of the overlapping area of ​​the orthographic projection of the first shielding layer on the first surface and the orthographic projection of the reinforcing sheet on the first surface to the size of the reinforcing sheet is greater than or equal to 30%.

[0015] Optionally, the first shielding layer and the reinforcing sheet are spaced apart, and the flexible circuit board further includes a transition structure, the transition structure is located on the second surface, and the transition structure connects the reinforcing sheet and the first shielding layer.

[0016] Optionally, the board body also includes a second substrate layer and a second wiring layer, the second substrate layer and the second wiring layer are stacked in sequence on the side of the first substrate layer close to the first surface, and the orthographic projection of the second substrate layer on the first surface does not overlap with the orthographic projection of the reinforcement sheet on the first surface; the flexible circuit board also includes a plurality of components, and the board body also has a plurality of second openings located at the second end, the plurality of components are respectively located in one of the second openings, and the components and the second wiring layer are connected through the second openings.

[0017] Optionally, the board body further has a third opening located at the second end, and the third opening is located on the second surface, and a portion of the first shielding layer is located in the third opening and connected to a grounding structure in the first routing layer.

[0018] On the other hand, a display device is provided, comprising a display panel and any one of the above-mentioned flexible circuit boards, wherein the flexible circuit board is located on the back side of the display panel and is electrically connected to the display panel, and the second surface is located on a side of the first surface away from the display panel.

[0019] The beneficial effects brought about by the technical solution provided by the present disclosure include at least: by electrically connecting the first shielding layer with the reinforcing sheet on the back side of the board body for setting the connector, the electrostatic and electromagnetic protection capabilities of the FPC are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 is a schematic diagram of a cross-sectional structure of an FPC provided in an embodiment of the present disclosure;

[0022] Figure 2 yes Figure 1 A partial enlarged schematic diagram of

[0023] Figure 3 is a schematic diagram of a planar structure of an FPC provided by an embodiment of the present disclosure;

[0024] Figure 4 is a schematic diagram of a cross-sectional structure of another FPC provided in an embodiment of the present disclosure;

[0025] Figure 5 is a schematic diagram of a planar structure of an FPC provided by an embodiment of the present disclosure;

[0026] Figure 6 is a schematic diagram of a cross-sectional structure of another FPC provided in an embodiment of the present disclosure;

[0027] Figure 7 is a schematic diagram of a planar structure of an FPC provided by an embodiment of the present disclosure;

[0028] Figure 8 is a schematic diagram of a cross-sectional structure of another FPC provided in an embodiment of the present disclosure;

[0029] Fig. 9 is a schematic diagram of a planar structure of an FPC provided by an embodiment of the present disclosure;

[0030] Fig.10is a schematic diagram of a cross-sectional structure of another FPC provided in an embodiment of the present disclosure;

[0031] Fig.11 is a schematic diagram of a planar structure of an FPC provided by an embodiment of the present disclosure;

[0032] Fig.12 It is a schematic diagram of a process of manufacturing a flexible circuit board provided by an embodiment of the present disclosure;

[0033] Fig.13 It is a partial schematic diagram of a planar structure of a display device provided by an embodiment of the present disclosure.

[0034] Legend:

[0035] 1. FPC x, first direction y, second direction 10, connection part

[0036] 11, board 11a, first surface 11b, second surface 11c, first opening 11d, second opening 11e, third opening 112, first substrate layer 113, second substrate layer 114, first wiring layer 115, second wiring layer 116, third wiring layer 117, fourth wiring layer 118, first adhesive layer 119, second adhesive layer 120, third adhesive layer 121, first protective layer 122, second protective layer

[0037] 12, first shielding layer 12a, first part 13, reinforcing sheet 14, connector 15, conductive adhesive 16, second shielding layer 17, fourth adhesive layer 18, transfer structure 19, components 20, non-conductive adhesive 21, adhesive layer

[0038] 3. Display Panel DETAILED DESCRIPTION

[0039] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0040] The terms used in the embodiments of the present disclosure are only used to explain the embodiments of the present disclosure, and are not intended to limit the present disclosure. Unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present disclosure should be the usual meanings understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second", "third" and similar words used in the patent application specification and claims of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, similar words such as "one" or "one" do not indicate quantitative restrictions, but indicate that there is at least one. Similar words such as "include" or "comprise" mean that the elements or objects appearing in front of "include" or "comprise" cover the elements or objects listed after "include" or "comprise" and their equivalents, and do not exclude other elements or objects. The directional terms mentioned in the present disclosure, such as "top", "bottom", "up", "down", "left" or "right", etc., are only referenced to the directions of the drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the embodiments of the present disclosure, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present disclosure.

[0041] In the related art, a flexible circuit board includes a board body, a first shielding layer, a reinforcing sheet and a connector, wherein the board body has a first surface and a second surface opposite to each other, and the board body has a first end and a second end opposite to each other in the length direction of the board body. The connector is located at the first end and on the first surface, and the connector is connected to the board body. The reinforcing sheet is located on the second surface and on the first end, and the orthographic projection of the connector on the first surface and the orthographic projection of the reinforcing sheet on the first surface at least partially overlap. The first shielding layer is located on the second surface, and the first shielding layer and the reinforcing sheet are arranged at intervals. Since the first shielding layer and the reinforcing sheet are arranged at intervals, there is no electrical connection between the first shielding layer and the reinforcing sheet. For example, the distance between the edge of the orthographic projection of the first shielding layer on the first surface and the edge of the orthographic projection of the reinforcing sheet on the first surface is about 1 mm. During use, electromagnetic interference and electrostatic damage problems may occur in the gap between the first shielding layer and the reinforcing sheet. As the internal design of electronic products becomes more and more complex, the above-mentioned electromagnetic interference and electrostatic damage problems are more likely to occur in high-end products, resulting in a decrease in the signal stability of the lines near the connector and electrostatic damage to the lines near the connector.

[0042] To this end, the embodiment of the present disclosure electrically connects the first shielding layer to the reinforcing sheet to improve the problem of poor electrostatic and electromagnetic protection capabilities on the back of the connector due to the spacing between the first shielding layer and the reinforcing sheet.

[0043] Figure 1 is a schematic diagram of a cross-sectional structure of an FPC provided in an embodiment of the present disclosure, Figure 2 yes Figure 1 A partial enlarged schematic diagram of Figure 1 and Figure 2 As shown, the FPC 1 includes a board 11, a first shielding layer 12, a reinforcing sheet 13 and a connector 14. The board 11 has a first surface 11a and a second surface 11b opposite to each other, and the board 11 has a first end and a second end in the length direction (first direction x) of the board 11. The connector 14 is located at the first end and on the first surface 11a, and the connector 14 is connected to the board 11. The reinforcing sheet 13 is located on the second surface 11b and at the first end. The first shielding layer 12 is located on the second surface 11b, and the first shielding layer 12 is electrically connected to the reinforcing sheet 13. Figure 3 is a schematic diagram of a planar structure of an FPC provided by an embodiment of the present disclosure, and Figure 1 yes Figure 3 Schematic diagram of the cross-sectional structure along the AA section line. Figure 3 As shown, the orthographic projection of the connector 14 on the first surface 11 a at least partially overlaps with the orthographic projection of the reinforcing sheet 13 on the first surface 11 a .

[0044] By electrically connecting the reinforcing sheet 13 to the first shielding layer 12, if static electricity appears on the back of the connector 14, the static electricity current can be conducted out from the back of the connector 14 along the electrically connected reinforcing sheet 13 and the first shielding layer 12, thereby providing better static electricity protection in the connector 14 area (the back of the connector 14); and because the structure between the electrically connected reinforcing sheet 13 and the first shielding layer 12, and the area of ​​the positive projection of the reinforcing sheet 13 and the first shielding layer 12 on the first surface 11a are larger than the area of ​​the positive projection of the reinforcing sheet 13 and the first shielding layer 12 arranged at intervals on the first surface 11a in the related art, the embodiment of the present disclosure provides better electromagnetic protection in the connector 14 area (the back of the connector 14).

[0045] It should be noted that the first end and the second end of the plate body 11 are as follows Figure 3 In the embodiment shown, the area on the left or right side does not mean Figure 3 The area closest to the left side and the area closest to the right side of the plate body 11 in the illustrated embodiment.

[0046] For example, Figures 1 to 3 As shown, the FPC further includes a conductive adhesive 15, the reinforcing sheet 13 and the board body 11 are connected by the conductive adhesive 15, and the reinforcing sheet 13 and the first shielding layer 12 are connected by the conductive adhesive 15, so as to realize the electrical connection between the reinforcing sheet 13 and the first shielding layer 12. Figures 1 to 3 As shown, the reinforcing sheet 13, the conductive adhesive 15, and the first shielding layer 12 are connected in sequence.

[0047] For example, Figures 1 to 3As shown, the orthographic projection of the first shielding layer 12 on the first surface 11a partially overlaps with the orthographic projection of the reinforcing sheet 13 on the first surface 11a. By extending the first shielding layer 12 to the area where the reinforcing sheet 13 is located, the connection between the reinforcing sheet 13 and the first shielding layer 12 is further ensured to be reliable, thereby ensuring the electrical connection between the first shielding layer 12 and the reinforcing sheet 13 is reliable, and the design process is relatively simple and easy to implement.

[0048] In other possible embodiments, there is a gap between the edge of the orthographic projection of the first shielding layer 12 on the first surface 11a and the orthographic projection of the reinforcing sheet 13 on the first surface 11a. The orthographic projection of the conductive adhesive 15 on the first surface 11a partially overlaps with the orthographic projection of the first shielding layer 12 on the first surface 11a, and the orthographic projection of the conductive adhesive 15 on the first surface 11a partially overlaps with the orthographic projection of the reinforcing sheet 13 on the first surface 11a. That is, the first shielding layer 12 and the reinforcing sheet 13 are spaced apart, but the conductive adhesive 15 is applied outside the area of ​​the reinforcing sheet 13 until it is connected to the first shielding layer 12. This method can also achieve electrical connection between the first shielding layer 12 and the reinforcing sheet 13.

[0049] For example, Figure 3 As shown, the ratio of the area of ​​the overlapped region of the orthographic projection of the first shielding layer 12 on the first surface 11a and the orthographic projection of the reinforcing sheet 13 on the first surface 11a to the area of ​​the orthographic projection of the reinforcing sheet 13 on the first surface is greater than or equal to 10%. The overlapping area is set to be greater than or equal to 10% to ensure that the overlapped portion of the first shielding layer 12 and the reinforcing sheet 13 is large enough, so that the electrostatic and electromagnetic protection capabilities of the back of the connector in the FPC are better.

[0050] Exemplarily, the first shielding layer 12 includes a first portion 12a located at the first end, and the orthographic projection of the first shielding layer 12 on the first surface 11a, and the portion that overlaps with the orthographic projection of the reinforcing sheet 13 on the first surface 11a is the orthographic projection of the first portion 12a on the first surface 11a. The ratio of the size of the first portion 12a in the second direction y to the size of the reinforcing sheet 13 in the second direction y is greater than or equal to 30%, and the second direction y is the width direction of the board body 11. If the ratio of the size of the first portion 12a in the second direction y to the size of the reinforcing sheet 13 in the second direction y is too small, the first portion 12a may be narrow, which may result in a large current in the process of static electricity flowing through the reinforcing sheet 13 and the first shielding layer 12 if there is static electricity on the back of the connector.

[0051] Exemplarily, the connector 14 is a board to board (BTB) connector or a zero insertion force (ZIF) connector. Different types of connectors can be selected in different application scenarios. For example, in display devices, board to board connectors are often used.

[0052] For example, Figure 2 As shown, the board 11 includes a first substrate layer 112 and a first wiring layer 114. The first wiring layer 114 is located on a side of the first substrate layer 112 away from the first surface 11a. The first wiring layer 114 may be provided with a grounding structure and wiring connected to the connector 14.

[0053] Optionally, the board body 11 also includes a first opening located at the first end, and the first opening is located on the second surface, so as to facilitate setting a grounding exposed copper area on the back of the connector, so that the conductive glue is electrically connected to the grounding structure in the first wiring layer through the first opening, further improving the electrostatic and electromagnetic protection capabilities.

[0054] For example, Figure 1 and Figure 2 As shown, the board body 11 also includes a second substrate layer 113 and a second wiring layer 115, and the second substrate layer 113 and the second wiring layer 115 are stacked in sequence on the side of the first substrate layer 112 close to the first surface 11a, and the orthographic projection of the second substrate layer 113 on the first surface 11a does not overlap with the orthographic projection of the reinforcement sheet 13 on the first surface 11a, that is, there is a first substrate layer 112 under the connector, but no second substrate layer 113. The flexible circuit board also includes a plurality of components 19, and the board body 11 also has a plurality of second openings 11d located at the second end, and the plurality of components 19 are respectively located in one of the second openings 11d, and the components 19 and the second wiring layer 115 are connected through the second openings 11d. More substrate layers are arranged at the second end of the FPC, and more wiring layers are arranged accordingly to facilitate the arrangement of components. Multiple wiring layers facilitate wiring and can improve the strength of the second end of the flexible circuit board. Fewer substrate layers and correspondingly fewer wiring layers are arranged at the first end to facilitate bending. Optionally, the plurality of components 19 may include resistors, capacitors, or touch chips.

[0055] For example, Figure 2 As shown, the FPC further includes a second shielding layer 16, which is located on the first surface 11a of the board body 11. That is, the first shielding layer 12 and the second shielding layer 16 are respectively located on two opposite surfaces of the board body 11, which can further improve the electrostatic and electromagnetic protection capabilities of the FPC. For example, Figure 1 and Figure 2 As shown, the second shielding layer 16 includes a plurality of avoidance holes, and the orthographic projections of the plurality of components 19 on the first surface 11 a are located within the orthographic projections of the plurality of avoidance holes on the first surface 11 a . The arrangement of the plurality of avoidance holes facilitates exposure of the plurality of components 19 .

[0056] For example, Figure 2As shown, the FPC also has a back adhesive layer 21, which is located on the side of the first shielding layer 12 away from the board body 11. The back adhesive layer 21 is provided to facilitate fixing the FPC, for example, to stick and fix the FPC to the back of the display panel.

[0057] For example, Figure 3 As shown, the FPC has a connecting portion 10, which facilitates the connection of the FPC with other structures in the display device, such as the display panel.

[0058] by Figures 1 to 3 Taking the illustrated embodiment as an example, the structure of each layer in the plate body 11 is exemplarily described below.

[0059] For example, Figure 2 As shown, the board body 11 further includes a third routing layer 116, a fourth routing layer 117, a first adhesive layer 118, a second adhesive layer 119, a third adhesive layer 120, a first protective layer 121, and a second protective layer 122. The first protective layer 121, the second adhesive layer 119, the first routing layer 114, the first substrate layer 112, the third routing layer 116, the first adhesive layer 118, the fourth routing layer 117, the second substrate layer 113, the second routing layer 115, the third adhesive layer 120, and the second protective layer 122 are stacked in sequence. Among them, the second opening 11d penetrates the third adhesive layer 120 and the second protective layer 122.

[0060] in, Figure 3 The connecting portion 10 shown may be a portion of the first substrate layer 112 and a portion of the first wiring layer 114, wherein the first wiring layer 114 includes a plurality of first conductive sheets (also called gold fingers) for electrical connection with the display panel; or, the connecting portion 10 may be a portion of the second substrate layer 113 and a portion of the fourth wiring layer 117, wherein the fourth wiring layer 117 includes a plurality of first conductive sheets for electrical connection with the display panel.

[0061] In other possible embodiments, more routing layers may be provided, as long as the number of routing layers at the second end is greater than the number of routing layers at the first end.

[0062] In other possible embodiments, routing layers having the same number of layers may be provided at the first end and the second end.

[0063] Optionally, the first substrate layer 112 and the second substrate layer 113 are made of PI (Polyimide), which has good bending performance and can ensure the overall bending performance of the FPC. The first substrate layer 112 and the second substrate layer 113 can also be made of PE (Polyethylene), PET (polyethylene glycolterephthalate), etc.

[0064] Optionally, the first wiring layer 114 , the second wiring layer 115 , the third wiring layer 116 and the fourth wiring layer 117 are made of copper, such as rolled copper or electrolytic copper.

[0065] Alternatively, if Figure 3 As shown, the first substrate layer 112, the first routing layer 114 and the third routing layer 116 located on both sides of the first substrate layer 112 extend from the first end to the second end, and the second substrate layer 113, the second routing layer 115 and the fourth routing layer 117 located on both sides of the second substrate layer 113 are located at the second end, that is, the second routing layer 115 and the fourth routing layer 117 are not located under the connector 14.

[0066] Optionally, the first protective layer 11 and the second protective layer 15 are made of PI, thereby providing protection for the FPC.

[0067] Optionally, the materials of the first adhesive layer 118 , the second adhesive layer 119 and the third adhesive layer 120 may be acrylic hot melt adhesive, polyurethane adhesive, epoxy resin adhesive, etc.

[0068] Optionally, the thickness of the first adhesive layer 118 is greater than the thickness of the second adhesive layer 119, and the thickness of the first adhesive layer 118 is greater than the thickness of the third adhesive layer 120, so as to bond the connected first routing layer 114, the first substrate layer 112, and the third routing layer 116 as a whole, and the connected second routing layer 115, the second substrate layer 113, and the fourth routing layer 117 as a whole.

[0069] Figure 4 is a schematic diagram of a cross-sectional structure of another FPC provided in an embodiment of the present disclosure, Figure 5 Schematic diagram of a planar structure of an FPC provided by an embodiment of the present disclosure. Figures 1 to 3 Compared with the embodiment shown, Figure 4 and Figure 5In the illustrated embodiment, the board 11 further has a first opening 11c located at the first end, and the first opening 11c is located on the second surface 11b, the orthographic projection of the first opening 11c on the first surface 11a is located within the orthographic projection of the reinforcing sheet 13 on the first surface 11a, the reinforcing sheet 13 is electrically connected to the first wiring layer 114, and the portion of the first wiring layer 114 connected to the reinforcing sheet 13 is used for grounding, and this portion of the first wiring layer 114 can also be called a grounding structure. The first opening 11c set on the back of the connector 14 is a grounding exposed copper area, and the setting of the first opening 11c can improve the electrostatic protection capability of the connector 14.

[0070] For example, Figure 4 As shown, the board body 11 also has a third opening 11e located at the second end, and the third opening 11e is located on the second surface 11b, the first shielding layer 12 is located in the third opening 11e and connected to the first wiring layer 114, and the first wiring layer 114 is connected to the first shielding layer 12. The portion of the first wiring layer 114 connected to the first shielding layer 12 is used for grounding. The third opening 11e is provided at the second end, that is, the grounded copper exposed area is provided on the back of the component 19, which can improve the electrostatic protection capability.

[0071] For example, Figure 4 As shown, the first opening 11 c penetrates through 121 and 119 , and the third opening 11 e penetrates through the first protective layer 121 and the second adhesive layer 119 .

[0072] exist Figure 4 and Figure 5 In the illustrated embodiment, the orthographic projection of the first portion 12a on the first surface 11a is located on one side of the orthographic projection of the first opening 11c on the first surface 11a. By extending the first shielding layer 12 to the side of the first opening close to the second end, the first shielding layer 12 and the conductive adhesive are reliably connected, thereby ensuring a reliable electrical connection between the first shielding layer 12 and the reinforcing sheet 13.

[0073] Alternatively, if Figure 4 and Figure 5 As shown, the flexible circuit board also includes a conductive glue 15, which is filled in the first opening 11c. Since the first shielding layer 12 and the reinforcing sheet 13 are connected, the grounded copper exposed area on the back of the connector 14, the conductive glue, the reinforcing sheet, and the first shielding layer are electrically connected.

[0074] Figure 6 is a schematic diagram of a cross-sectional structure of another FPC provided in an embodiment of the present disclosure, Figure 7 Schematic diagram of a planar structure of an FPC provided by an embodiment of the present disclosure. Figures 1 to 3 Compared with the embodiment shown, Figure 6 and Figure 7 In the embodiment shown, the plate body 11 has Figure 4 and Figure 5 In the embodiment shown, the first opening 11c and the third opening 114f are similar. In addition, the orthographic projection of the first portion 12a on the first surface 11a surrounds the orthographic projection of the first opening 11c on the first surface 11a. This design can further increase the overlapping area of ​​the first shielding layer 12 and the reinforcing sheet 13. Figure 5 and Figure 6 The illustrated embodiment further improves the electrostatic and electromagnetic protection capabilities.

[0075] Figure 8 is a schematic diagram of a cross-sectional structure of another FPC provided in an embodiment of the present disclosure, Fig. 9 Schematic diagram of a planar structure of an FPC provided by an embodiment of the present disclosure. Figures 1 to 3 Compared with the embodiment shown, Figure 8 and Fig. 9 In the embodiment shown, the plate body 11 has Figure 4 and Figure 5 In the embodiment shown, there are similar first openings 11c and third openings 11e. In addition, the orthographic projection of the first opening 11c on the first surface 11a is located within the orthographic projection of the first portion 12a on the first surface 11a. This design can further increase the area of ​​the orthographic projection of the first portion 11a on the first surface 11a, that is, this design can further increase the overlapping area of ​​the first shielding layer 12 and the reinforcing sheet 13, compared with Figure 6 and Figure 7 The embodiment shown further improves the electrostatic and electromagnetic protection capabilities. Figure 8 and Fig. 9 In the illustrated embodiment, the grounded exposed copper area on the back side of the connector 14 located in the first opening 11 c is in direct contact with the first shielding layer 12 .

[0076] Above Figures 1 to 9 In the embodiments shown, the electrical connection between the first shielding layer 12 and the reinforcing sheet 13 is achieved by extending the first shielding layer 12 toward the first end until the first shielding layer 12 overlaps the reinforcing sheet 13. In other possible embodiments, the electrical connection between the first shielding layer 12 and the reinforcing sheet 13 may not be achieved in this manner. Fig.10 Other ways of achieving electrical connection between the first shielding layer 12 and the reinforcing sheet 13 are exemplified.

[0077] Fig.10 is a schematic diagram of a cross-sectional structure of another FPC provided in an embodiment of the present disclosure, Fig.11 is a schematic diagram of a planar structure of an FPC provided by an embodiment of the present disclosure, and Fig.10 yes Fig.11 Schematic diagram of the local cross-section structure along the BB section line. Fig.10 and Fig.11As shown, the first shielding layer 12 is spaced apart from the reinforcing sheet 13, and the FPC further includes a transition structure 18, which is located on the second surface 11b, and the transition structure 11b connects the reinforcing sheet 13 and the first shielding layer 12. By providing the transition structure 18, the reinforcing sheet 13 and the first shielding layer 12 are electrically connected, thereby improving the electrostatic and electromagnetic protection capabilities of the FPC.

[0078] Optionally, the transition structure 11 b includes a main body and an extension portion, the main body is located on a side of the first protective layer 121 away from the first surface and connected to the reinforcing sheet 13 , and the extension portion is used to connect to the first protective layer 121 .

[0079] Optionally, the transfer structure 18 is made of a conductive material, such as a metal material such as copper.

[0080] Optionally, the orthographic projection of the transition structure 18 on the first surface 11a may be Fig.10 and Fig.11 The rectangle shown may also be other shapes, which is not limited in the embodiments of the present disclosure.

[0081] Optionally, the reinforcing sheet 13 and the body 11 are connected by non-conductive glue or conductive glue.

[0082] Fig.12 FIG. 1 is a flow chart of a method for manufacturing a flexible circuit board provided by an embodiment of the present disclosure. Fig.12 As shown, the method includes:

[0083] In step S1, a plate body is provided, wherein the plate body has a first surface and a second surface opposite to each other, and the plate body has a first end and a second end in a length direction of the plate body;

[0084] In step S2, a first shielding layer, a reinforcing sheet and a connector are arranged on the board.

[0085] The connector is located on the first surface and at the first end, the connector is connected to the board, the reinforcing sheet is located on the second surface and at the first end, the orthographic projection of the connector on the first surface and the orthographic projection of the reinforcing sheet on the first surface at least partially overlap, the first shielding layer is located on the second surface, and the first shielding layer is electrically connected to the reinforcing sheet.

[0086] Exemplarily, step S2 includes: firstly manufacturing a first shielding layer of a specific shape by die cutting or laser cutting, and then pasting the first shielding layer to the second surface of the board.

[0087] Exemplarily, a conductive adhesive tape or a non-conductive adhesive tape is first attached to the board body 11, and then the reinforcing sheet is attached to achieve connection between the board body and the reinforcing sheet. In other possible embodiments, a liquid conductive adhesive or a non-conductive adhesive is first coated on the board body 11, and then the reinforcing sheet is attached to achieve connection between the board body and the reinforcing sheet.

[0088] Exemplarily, the board and the connector are connected by SMT (Surface Mounted Technology) process.

[0089] Fig.13 FIG. 1 is a partial schematic diagram of a planar structure of a display device provided by an embodiment of the present disclosure. Fig.13 As shown, the display device includes a display panel 3 and any one of the above-mentioned flexible circuit boards 1, the flexible circuit board 1 is located on the back of the display panel 3, and the flexible circuit board 1 is electrically connected to the display panel 3, and the second surface is located on the side of the first surface away from the display panel 3.

[0090] Illustratively, the display device provided in the embodiments of the present disclosure may be any product or component with a display function, such as a mobile phone, a tablet computer, a display, or the like.

[0091] For example, in the display device provided in the embodiment of the present disclosure, the display panel may be: a liquid crystal display panel, an OLED (Organic Light Emitting Diode) display panel, a QLED (Quantum DotLight Emitting Diode) display panel, etc., and the embodiment of the present disclosure does not make any specific limitations here.

[0092] The display device has the same effect as the aforementioned FPC, which will not be described in detail here.

[0093] Exemplarily, the display panel 3 has a side bent toward the back of the display panel, so that a DDIC (Display Driver IC) (not shown) is provided on the portion of the display panel 3 bent toward the back of the display panel. This design can minimize the area of ​​the non-display area B, that is, this design is conducive to a narrow frame design. Here, the back of the display panel 3 refers to the other surface of the display panel 3 opposite to the light emitting surface.

[0094] Exemplarily, one side of the display panel is bent toward the back of the display panel, and the bent portion of the display panel has a packaged circuit board (not shown in the figure). This packaged circuit board integrated with the display panel is called a COP (Chip On Pi, chip on flexible material) circuit board. In other possible embodiments, the packaged circuit board may also be a COG (Chip On Glass, chip on glass) circuit board or a COF (Chip On Film, chip on film) circuit board. The packaged circuit board includes a DDIC.

[0095] Exemplarily, the FPC in the embodiment of the present disclosure is a main flexible printed circuit (MFPC). The display device further includes a central processing unit (not shown in the figure), the connecting portion 10 of the FPC1 is connected to the DDIC, and the first end of the FPC1 can be bent and connected to the central processing unit of the whole machine through a connector. The central processing unit of the whole machine controls the DDIC on the package circuit board through the FPC1, and then controls the display panel 3 to display the picture.

[0096] Exemplarily, the package circuit board has a plurality of second conductive sheets, and the plurality of second conductive sheets correspond one to one with the plurality of first conductive sheets in the connection portion of the FPC. The display device further includes an ACF film (Anisotropic Conductive Film), the ACF film is located between the first conductive sheet and the second conductive sheet, and the ACF film includes a glue layer and a plurality of metal balls (such as gold balls) distributed in the glue layer. The first conductive sheet, the ACF film, and the second conductive sheet are connected in sequence.

[0097] Exemplarily, a back film is further disposed on the back of the display panel 3 to protect the display panel 3 .

[0098] Exemplarily, a grounding layer is provided on the side of the back film away from the display panel, and the grounding layer includes a SCF (SuperClean Foam) layer, also known as a heat dissipation film. The first shielding layer of FPC1 is connected to the SCF layer.

[0099] Exemplarily, the display device further includes a polarizer, and the polarizer is located on a side of the display panel 3 away from the FPC1 , that is, the polarizer is located on the light emitting surface of the display panel.

[0100] Exemplarily, the display device further includes a cover plate, which is located on the light-emitting surface of the display panel. Optionally, the cover plate can be made of transparent materials such as acrylic or glass.

[0101] The above are only optional embodiments of the present disclosure and are not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure should be included in the protection scope of the present disclosure.

Claims

1. A flexible circuit board, It is characterized in that The flexible circuit board comprises a board body, a first shielding layer, a reinforcing sheet and a connector, wherein the board body has a first surface and a second surface opposite to each other, and the board body has a first end and a second end in the length direction of the board body; The connector is located on the first surface and at the first end, and the connector is connected to the board; The reinforcing sheet is located on the second surface and the first end, and the orthographic projection of the connector on the first surface at least partially overlaps with the orthographic projection of the reinforcing sheet on the first surface; The first shielding layer is located on the second surface, and the first shielding layer is electrically connected to the reinforcing sheet.

2. The flexible circuit board according to claim 1, It is characterized in that The flexible circuit board further includes a conductive adhesive, the reinforcing sheet and the board body are connected via the conductive adhesive, and the reinforcing sheet and the first shielding layer are connected via the conductive adhesive.

3. The flexible circuit board according to claim 2, It is characterized in that The orthographic projection of the first shielding layer on the first surface partially overlaps with the orthographic projection of the reinforcing sheet on the first surface.

4. The flexible circuit board according to claim 3, It is characterized in that A ratio of an area of ​​an overlapped region of an orthographic projection of the first shielding layer on the first surface and an orthographic projection of the reinforcing sheet on the first surface to an area of ​​an orthographic projection of the reinforcing sheet on the first surface is greater than or equal to 10%.

5. The flexible circuit board according to claim 4, It is characterized in that The board body includes a first substrate layer and a first routing layer, the first routing layer is located on a side of the first substrate layer away from the first surface, the board body also has a first opening, the first opening is located on the second surface, the orthographic projection of the first opening on the first surface is located within the orthographic projection of the reinforcement sheet on the first surface, and the reinforcement sheet is electrically connected to the grounding structure in the first routing layer through the first opening.

6. The flexible circuit board according to claim 5, It is characterized in that An orthographic projection of the first shielding layer on the first surface is located on one side of an orthographic projection of the first opening on the first surface.

7. The flexible circuit board according to claim 5, It is characterized in that The orthographic projection of the first shielding layer on the first surface surrounds the orthographic projection of the first opening on the first surface.

8. The flexible circuit board according to claim 5, It is characterized in that An orthographic projection of the first opening on the first surface is located within an orthographic projection of the first shielding layer on the first surface.

9. The flexible circuit board according to any one of claims 3 to 8, It is characterized in that In the width direction of the plate body, the ratio of the size of the overlapping area of ​​the orthographic projection of the first shielding layer on the first surface and the orthographic projection of the reinforcing sheet on the first surface to the size of the reinforcing sheet is greater than or equal to 30%.

10. The flexible circuit board according to claim 1, It is characterized in that The first shielding layer and the reinforcing sheet are spaced apart from each other. The flexible circuit board further comprises a transition structure, which is located on the second surface and connects the reinforcing sheet and the first shielding layer.

11. The flexible circuit board according to any one of claims 5 to 8, It is characterized in that The board body further includes a second substrate layer and a second wiring layer, the second substrate layer and the second wiring layer are sequentially stacked on a side of the first substrate layer close to the first surface, and an orthographic projection of the second substrate layer on the first surface does not overlap with an orthographic projection of the reinforcing sheet on the first surface; The flexible circuit board also includes a plurality of components. The board body also has a plurality of second openings located at the second end. The plurality of components are respectively located in one of the second openings. The components and the second wiring layer are connected through the second openings.

12. The flexible circuit board according to any one of claims 5 to 8, It is characterized in that The board body further has a third opening located at the second end, and the third opening is located on the second surface. A portion of the first shielding layer is located in the third opening and is connected to a grounding structure in the first wiring layer.

13. A display device, It is characterized in that The display device includes a display panel and a flexible circuit board as described in any one of claims 1 to 12, wherein the flexible circuit board is located on the back side of the display panel and is electrically connected to the display panel, and the second surface is located on a side of the first surface away from the display panel.

Images