A capacitive touch screen FPC structure

Abstract

The present invention relates to the field of capacitive touch screens, and in particular to a capacitive touch screen FPC structure, which is arranged on one side of the electrode lead-out line of the touch screen, one end of the FPC is connected to the electrode lead-out line by hot pressing and is installed on the cover plate bottom frame on one side of the electrode lead-out line of the touch screen; the FPC includes a substrate and a wiring arranged on the substrate; the substrate is divided into a binding part and a bending part; the binding part is attached to the cover plate bottom frame on one side of the electrode lead-out line of the touch screen; the bending part is connected to the side of the binding part away from the cover plate bottom frame; the bending part is provided with horizontally arranged through holes; one end of the wiring is arranged on the binding part and connected to the electrode lead-out line of the touch screen; the other end of the wiring passes through the middle area of ​​two adjacent through holes and extends to the side away from the binding part. The present invention reduces the frame width on one side of the electrode lead-out line of the touch screen to achieve a narrow frame design of the "chin" of the touch screen.

Description

Technical Field

[0001] The present invention relates to the field of capacitive touch screens, and in particular to a capacitive touch screen FPC structure. Background Art

[0002] A development trend in touch screen structure is the square narrow frame. In the usual design, the touch screen has three very narrow frames and one wider frame. The wider frame is because the lead wires of the two layers of electrodes of the touch screen are all led out from this side frame, and the lead wires are connected to the FPC circuit through hot pressing and binding; the root of the FPC is fixed by sticking tape on the cover plate on the side of the touch screen electrode lead wire, which increases the width of the frame on this side and limits the improvement of the screen-to-body ratio of the touch screen; it is very common on smartphones, and this is the reason why the "chin" of almost every mobile phone is wider than the "forehead". Summary of the invention

[0003] The purpose of the present invention is to provide a capacitive touch screen FPC structure, which reduces the frame width on one side of the touch screen electrode lead-out line to achieve a narrow frame design of the touch screen "chin".

[0004] In order to solve the above technical problems, the technical solution of the present invention is: a capacitive touch screen FPC structure is arranged on one side of the electrode lead wire of the touch screen, one end of the FPC is connected to the electrode lead wire by hot pressing and is installed on the cover plate bottom frame on one side of the electrode lead wire of the touch screen; the FPC includes a substrate and a wiring arranged on the substrate; the substrate is divided into a binding part and a bending part; the binding part is attached to the cover plate bottom frame on one side of the electrode lead wire of the touch screen; the bending part is connected to the side of the binding part away from the cover plate bottom frame; the bending part is provided with horizontally arranged through holes; one end of the wiring is arranged on the binding part and connected to the electrode lead wire of the touch screen; the other end of the wiring passes through the middle area of ​​two adjacent through holes and extends to the side away from the binding part.

[0005] According to the above scheme, the through holes are arranged at equal intervals.

[0006] According to the above solution, the width of the middle area between adjacent through holes is half of the horizontal width of the through holes.

[0007] According to the above scheme, when each two routing lines are grouped together and located between two adjacent through holes, the sum of the center distance between the two routing lines in each group of routing lines and the routing width of the two routing lines is less than the spacing between adjacent through holes; the middle area of ​​adjacent through holes is used to carry the routing lines.

[0008] According to the above solution, the through hole is rectangular.

[0009] According to the above solution, the longitudinal length of the through hole is greater than the horizontal width of the through hole.

[0010] According to the above scheme, the horizontal width of the through hole is 0.8mm and the longitudinal length is 2mm-3mm.

[0011] According to the above scheme, the routing width is no more than 30um, and the center distance between two routings is no more than 50um.

[0012] According to the above scheme, when two traces are grouped together and pass through the middle area of ​​two adjacent through holes, the spacing between two adjacent groups of traces shall not be less than 1.2 mm.

[0013] The present invention has the following beneficial effects: the present invention eliminates the adhesive area formed by the adhesive tape in the prior art, and adjusts the design of the bending area, performs a window processing on the bending part, and sets a through hole. The purpose of the window is to reduce the stress generated when the FPC is bent, and prevent the FPC from falling off when it is bound to the sensor, thereby preventing the circuit from being open. Compared with the prior art, the present invention meets the demand for preventing the circuit from being open, while eliminating the position occupied by the adhesive area, and reducing the width of the frame on one side of the touch screen electrode lead-out line, that is, the bottom frame of the cover plate, so as to realize the narrow frame design of the "chin" of the touch screen. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the FPC structure in an embodiment of the present invention;

[0015] Figure 2 This is a schematic diagram of the combination of the FPC and the cover plate in this embodiment;

[0016] Figure 3 It is a schematic diagram of the FPC structure in the prior art;

[0017] Figure 4 It is a schematic diagram of the combination of FPC and cover plate in the prior art.

[0018] Figure numerals: 1, substrate; 101, binding part; 102, bending part; 102a, through hole; 103, original part; 104, adhesive part; 2, wiring; 3, touch screen; 4, cover plate; 401, cover plate bottom frame. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the FPC structure in the prior art is first described below.

[0020] See also Figure 3 and Figure 4In the prior art, the FPC of the touch screen 3 is provided with a binding portion 101 of the cover bottom frame 401 attached to one side of the electrode lead-out line of the touch screen. The binding portion 101 refers to the area that is bound and connected to the sensor. The metal circuit bound to the sensor and the substrate that carries the metal circuit are provided in the binding portion 101 area. In the conventional design of the FPC of the touch screen 3, an adhesive portion 104 is formed in the root area of ​​the binding portion 101. The adhesive portion 104 is affixed with double-sided tape on the side that contacts the cover plate 4 to ensure that this part of the FPC can be firmly attached to the cover plate 4 of the touch screen 3. When the touch screen 3 is assembled, even if the FPC is bent 180 degrees, the stress generated by the bending will not cause poor contact between the FPC and the sensor, or even fall off in more serious cases. The adhesive portion 104 prevents the FPC from bending and generating stress during installation, causing the FPC to detach from the sensor. The bending portion 102 of the FPC bending area is a narrow area between the binding portion 101 and the original portion 103, and is bent from here when the whole machine is assembled. Figure 4 As shown, the adhesive portion 104 on the FPC is completely attached to the bottom frame of the cover plate 4, that is, the cover plate bottom frame 401. The width of the double-sided adhesive in the adhesive portion 104 needs to be at least 1 mm, and the process alignment accuracy must be reserved, which at least increases the width of the frame of the binding area on the side of the electrode lead wire of the touch screen 3, that is, the cover plate bottom frame 401 on the side of the touch screen electrode lead wire by 1.5 mm.

[0021] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] See also Figure 1 and Figure 2 , Figure 2 In the figure, the arrow X direction indicates the horizontal width direction, and the arrow Y direction indicates the longitudinal length direction. The present invention is a capacitive touch screen FPC structure, which is arranged on one side of the electrode lead wire of the touch screen 3, and one end of the FPC is connected to the electrode lead wire by hot pressing and installed on the cover bottom frame 401 on one side of the touch screen electrode lead wire; the FPC includes a substrate 1 and a wiring 2 arranged on the substrate 1;

[0023] The substrate 1 is divided into a binding portion 101 and a bending portion 102; the binding portion 101 is attached to the cover bottom frame 401 on one side of the touch screen electrode lead-out line, and the root of the binding portion 101 is flush with the bottom edge of the cover frame 4; the bending portion 102 is connected to the side of the binding portion 101 away from the cover bottom frame 401, that is, the bending portion 102 is connected to the root of the binding portion 101.

[0024] The traces 2 are a plurality of metal lines arranged longitudinally, one end of which is arranged at the same layer of the binding part 101 and connected to the electrode lead wires of the touch screen 3; the other end of the traces 2 passes through the bending part 102 and extends to the original part 103 where the FPC main circuit is arranged.

[0025] The bending portion 102 is provided with rectangular through holes 102a arranged horizontally and arranged at equal intervals. The longitudinal length of the through holes 102a is greater than the horizontal width of the through holes 102a, and the spacing width between adjacent through holes 102a is half of the horizontal width of the through holes 102a. The routing lines 2 located in the bending portion 102 are arranged as a group for every two routing lines 2. A window treatment is performed between every two groups of routing lines 2 located in the bending portion 102, that is, the above-mentioned through holes 102a are provided. Each group of routing lines 2 passes through the middle area of ​​two adjacent through holes 102a and extends to the side away from the binding portion 101. When every two routing lines 2 are arranged as a group between two adjacent through holes 102a, the sum of the center distance between the two routing lines 2 in each group of routing lines 2 and the width of the routing lines 2 of the two routing lines 2 is less than the spacing between the middle areas of the adjacent through holes 102a. After the window treatment is performed in the bending portion 102 area, the stress generated when the FPC is bent will be greatly reduced, and there will be no risk of pulling the FPC off the sensor.

[0026] In this embodiment, the horizontal width of the through hole 102a is 0.8mm, the vertical length is 2mm-3mm, the width of the line 2 is not more than 30um, the center distance between adjacent pairs of lines 2 is not more than 50um, and when each pair of lines 2 passes through the middle area of ​​two adjacent through holes 102a as a group, the distance between adjacent groups of lines 2 is more than 1.2mm. In this embodiment, through this technical solution, the position of the adhesive part 104 is reduced, so that the border of the binding area of ​​the touch screen 3, that is, the cover bottom frame 401 on the side of the touch screen electrode lead wire, is reduced. Figure 4 4a in is adjusted to Figure 2 In 4b, the cover bottom frame 401 can save 11.5mm-3mm of space, and this size is related to the specific product size.

[0027] Compared with the conventional design, the present invention eliminates the design of the double-sided adhesive portion 104. In order to avoid pulling the sensor when the FPC is bent due to the lack of the adhesive portion 104, the present invention performs a window treatment on the FPC bending portion 102 to reduce the stress generated when the FPC is bent, prevent the FPC from falling off when bound to the sensor, and thus prevent the circuit from being open. The present invention meets the need to prevent the circuit from being open while eliminating the position occupied by the adhesive area, reducing the frame width on one side of the electrode lead-out line of the touch screen 3, so as to achieve a narrow frame design of the "chin" of the touch screen 3.

[0028] The parts not involved in the present invention are the same as the prior art or are implemented by using the prior art.

[0029] The above contents are further detailed descriptions of the present invention in combination with specific implementation methods, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A capacitive touch screen FPC structure, which is arranged on one side of the electrode lead wire of the touch screen, one end of the FPC is connected to the electrode lead wire by hot pressing and is installed on the cover plate bottom frame on one side of the electrode lead wire of the touch screen; characterized in that: The FPC includes a substrate and a wiring arranged on the substrate; The substrate is divided into a binding part and a bending part; the binding part is attached to the cover plate bottom frame on one side of the touch screen electrode lead-out line; the bending part is connected to the side of the binding part away from the cover plate bottom frame; The bending portion is provided with horizontally arranged through holes; One end of the wiring is arranged at the binding part and connected to the electrode lead wire of the touch screen; the other end of the wiring passes through the middle area of ​​two adjacent through holes and extends to a side away from the binding part; The through holes are arranged at equal intervals; The routing lines at the bending portion are arranged in groups of two. When each group of routing lines is located between two adjacent through holes, the sum of the center distance between the two routing lines in each group of routing lines and the routing width of the two routing lines is less than the spacing between the middle areas of the adjacent through holes.

2. The capacitive touch screen FPC structure according to claim 1, characterized in that: The width of the middle area of ​​adjacent through holes is half of the horizontal width of the through holes.

3. The capacitive touch screen FPC structure according to claim 1, characterized in that: The through hole is rectangular.

4. The capacitive touch screen FPC structure according to claim 3, characterized in that: The longitudinal length of the through hole is greater than the horizontal width of the through hole.

5. The capacitive touch screen FPC structure according to claim 4, characterized in that: The through hole has a horizontal width of 0.8 mm and a longitudinal length of 2 mm to 3 mm.

6. The capacitive touch screen FPC structure according to claim 1, characterized in that: The trace width is no more than 30um, and the center distance between two traces is no more than 50um.

7. The capacitive touch screen FPC structure according to claim 1, characterized in that: When two traces are grouped together and pass through the middle area of ​​two adjacent through holes, the spacing between two adjacent groups of traces shall not be less than 1.2 mm.

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