WO2016123811A1

WO2016123811A1 - Capacitive touch screen and combination of same with flexible circuit board

Info

Publication number: WO2016123811A1
Application number: PCT/CN2015/072454
Authority: WO
Inventors: 陈鑫; 余晓军; 魏鹏; 邹翔; 周瑜; 刘自鸿
Original assignee: 深圳市柔宇科技有限公司
Priority date: 2015-02-06
Filing date: 2015-02-06
Publication date: 2016-08-11
Also published as: CN105493015B; CN105493015A

Abstract

A capacitive touch screen (10), which can be connected to a flexible circuit board (FPC), wherein the FPC (30) comprises a plurality of first pins (32) which are disposed at intervals side by side. The capacitive touch screen (10) comprises a base material (12) and a lead area (24) provided on the base material (12), wherein the lead area (24) comprises a plurality of second pins (26) which are arranged at intervals side by side, the width of each second pin (26) is greater than that of each first pin (32), and a gap between adjacent second pins (26) is smaller than a gap between adjacent first pins (32). Since the gap between adjacent first pins (32) is relatively large, when small metal balls contained in ACF on the first pins (32) are connected, a short-circuit of the adjacent first pins (32) is unlikely to form. Additionally, since the width of the second pins (26) is greater than that of each first pin (32), even when the capacitive touch screen (10) slightly deviates relative to the FPC (30), a short-circuit between the pins is unlikely to occur. Also provided is a combination of the capacitive touch screen (10) and the FPC (30).

Description

Capacitive touch screen and its combination with flexible circuit board

Technical field

The present invention relates to touch screens, and more particularly to capacitive touch screens and combinations thereof with flexible circuit boards.

Background technique

Single-layer touch screens have become a trend more and more because of the current demand for reduced touch screens and reduced cost. The single-layer touch screen refers to the simultaneous formation of conductive patterns for driving and sensing on the substrate, and the driving and sensing interactions are not required in the pattern area by bridging or jumping. Since the performance of the single-layer touch screen is similar to that of the conventional single-layer bridge or double-layer structure, it has been rapidly developed and is now capable of stable mass production.

Single-layer touch screens are used to connect flexible circuit boards (FPCs) with many pins. For example, a single-ended output screen with a size of about 5 inches has more than two hundred pins. Thus, one design can have a pitch value of 0.27 mm, a pin width of 0.12 mm, and a gap between pins of 0.15 mm. At the same time, the FPC is the same as this design, so that it is fully aligned during bonding. Even if there is some offset, because of the wide spacing and short circuit, this design will affect the contact resistance.

In the case where the distance between the touch screen and the pins of the FPC needs to be made smaller, the FPC pin and the touch screen are hot pressed to make an anisotropic conductive film (ACF) attached to the lead. When the electrical connection pin and the touch screen are connected, the small metal balls of a few um to ten um in diameter included in the ACF are easily connected to form a short circuit of the adjacent pins. At the same time, due to the large number of pins, the touch screen and the FPC are slightly offset, and a short circuit is easily formed. In addition, the size of the flexible substrate is severely deformed, resulting in a perfect match between the FPC pin and the on-screen pin size, increasing the risk of short circuit.

Summary of the invention

Embodiments of the present invention provide a capacitive touch screen that can solve the above technical problems and its combination with a flexible circuit board.

A capacitive touch screen is connectable to a flexible circuit board (FPC), the FPC comprising a plurality of first pins arranged side by side. The capacitive touch screen includes a substrate and a lead region disposed on the substrate, the lead region includes a plurality of second pins disposed side by side, each second pin having a width greater than a width of each of the first leads, adjacent The pitch of the second pin is smaller than the pitch of the adjacent first pins.

A combination of a capacitive touch screen and a flexible circuit board (FPC), the FPC comprising a plurality of first pins arranged side by side, the capacitive touch screen comprising a substrate and a lead region disposed on the substrate, the lead region comprising The second pin is set side by side. The width of each second pin is greater than the width of each first pin, the spacing of adjacent second pins is smaller than the spacing of adjacent first pins, and each second pin is electrically connected to a corresponding first pin. .

In the technical solution of the present invention, the width of each of the second pins is greater than the width of each of the first pins, and the pitch of the adjacent second pins is smaller than the spacing of the adjacent first pins, and therefore, the first pin The small metal balls included in the ACF are also difficult to form a short circuit adjacent to the first pin. In addition, since the width of the second pin is larger than the width of each of the first pins, even if the touch screen and the FPC are slightly offset, the second pin is not easily short-circuited due to the shorting of the first pin. In this way, the bonding yield between the touch screen and the FPC is improved, and the production cost is also reduced.

DRAWINGS

The following figures are used to describe various embodiments of the invention in detail in conjunction with the specific embodiments. It should be understood that the various elements of the present invention are not to be construed as a

1 is a plan view showing a capacitive touch screen and an FPC in a separated state according to a preferred embodiment of the present invention.

2 is a schematic side view showing the capacitive touch screen of FIG. 1 fabricated by laser.

3 is a partially enlarged plan view of the capacitive touch screen of FIG. 1.

4 is a schematic view of the capacitive touch screen of FIG. 1 and the respective pins of the FPC in a state in which they are not in contact with each other.

Figure 5 is a schematic view of the pins of Figure 4 in contact with each other.

detailed description

The present invention will be further described in detail below with reference to a plurality of embodiments and the accompanying drawings. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Please refer to FIG. 1 , which shows a plan view of the capacitive touch screen 10 and the FPC 30 in a separated state before being mutually bonded. The FPC 30 has a first pin 32 and the capacitive touch screen 10 has a second lead for connecting with the first pin 32. The detailed structure of the foot 26, the first and

second pins

32, 26 is as follows. 2 and 3, which show a side view and a partially enlarged plan view of the capacitive touch screen 10, respectively. The capacitive touch screen 10 includes a substrate 12 and a conductive layer 14 disposed on the substrate 12.

The substrate 12 can be made of a transparent material, such as glass or polyethylene terephthalate (PET), to facilitate the production of touch-enabled display screen modules or other applications requiring transparency. When the capacitive touch screen 10 is required to have flexibility, the optional PET is used to fabricate the substrate 12, which has the advantages of good light transmission and flexibility, and is easy to manufacture. In the present embodiment, the substrate 12 made of PET has a thickness of about 0.015 to 0.2 millimeters (mm), preferably 0.1 mm, and the substrate within this thickness has good flexibility. Of course, the substrate 12 can also be made of a non-transparent material, such as a metal, without the need for other transparent properties.

The conductive layer 14 may be a transparent conductive film including a metal of a nanometer dimension, such as a film comprising a single metal, an alloy, a metal compound or a combination thereof in any combination of nanometer dimensions, for example, a film including nanowires, including nano metal particles. The film, the film including the nano metal mesh, may of course be a graphene film, a carbon nanotube film, an organic conductive polymer film, an Indium Tin Oxide (ITO) film or any combination thereof. In this embodiment, the conductive layer 14 is a transparent conductive nano-silver film, which is a film comprising a polymer matrix having nano-silver filaments, and the nano-silver filaments are uniformly distributed in the film to make the film transparent. And conductive features. The nanosilver film can be attached to the substrate 12 by coating, silk printing or spraying.

Preferably, the capacitive touch screen 10 further includes a protective layer 16 on the side of the substrate 12 facing away from the conductive layer 14, and the protective layer 16 may be fixed to the substrate 12 by a scratch-resistant material such as a polycarbonate material or the like.

The conductive layer 14 is formed thereon by laser light 11 to form a sensing region 22 located therebetween and a lead region 24 at the edge. Specifically, adjusting the parameters of the laser light 11 allows the laser light 11 to change the transparent conductive properties of the nanosilver film into a transparent and non-conductive manner without removing it. The laser parameters include pulse width, pulse flux, pulse energy, spot size, pulse repetition rate, etc. After rotating the appropriate parameters, the nano-silver in the irradiated portion will change from conductive to non-conductive, and at the same time, illuminated. The transparency of the portion hardly changes, and the exposed portion of the nanosilver film is hardly peeled off. Of course, in other embodiments, lead region 24 may also be formed from conductive layer 14 by a yellow light process or silk screen.

The sensing region 22 has a pattern 26 for sensing a touch, and a row line and a column line (not labeled) drawn from the pattern 26, wherein the row line and the column line are both disposed on one side of the sensing region 22. The lead region 24 has a plurality of the second pins 26 formed by the laser 11 illumination lines, and the second pins 26 are connected to the corresponding row lines and column lines so that the row lines and the column lines pass through the lead regions 24. Two pins 26 with The first pin 32 of the FPC is connected to an external circuit.

Please refer to FIG. 4 and FIG. 5 , which are schematic diagrams of the capacitive touch screen and the

respective pins

26 and 32 of the FPC when they are not in contact with each other and in contact with each other. The width B2 of the second pin 26 of the capacitive touch screen is greater than the width B1 of the first pin 32 of the FPC, and the pitch A2 of the adjacent second pin 26 is smaller than the pitch A1 of the adjacent first pin 32. Thus, when each of the first pins 32 is electrically connected to the corresponding second pin 26, the small metal balls included in the ACF on the first pin 32 are connected due to the large spacing of the adjacent first pins 32. It is also difficult to form a short circuit between adjacent first pins 32. In addition, since the width of the second pin 26 is larger than the width of each of the first pins 32, even if the touch screen and the FPC are slightly offset, the second pins 26 are not easily short-circuited by the first pins 32. A short circuit has occurred. As such, the bonding yield between the touch screen 10 and the FPC 30 is improved, and the production cost is also reduced.

Preferably, each of the first pins 32 is located between the corresponding one of the second pins 26 to reduce the risk of short circuit.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. Within the scope.

Claims

A capacitive touch screen is connectable to a flexible circuit board (FPC), the FPC includes a plurality of first pins arranged side by side, wherein the capacitive touch screen comprises a substrate and a lead region disposed on the substrate The lead region includes a plurality of second pins arranged side by side, each second pin has a width greater than a width of each of the first pins, and a spacing between adjacent second pins is smaller than a spacing between adjacent first pins.
The capacitive touch screen of claim 1 , wherein the capacitive touch screen further comprises a conductive layer disposed on the substrate, the plurality of first leads being formed by the conductive layer by laser.
The capacitive touch screen of claim 1 , wherein the capacitive touch screen further comprises a conductive layer disposed on the substrate, the plurality of first leads being formed by the conductive layer by a yellow light process or silk screen.
The capacitive touch panel according to claim 2 or 3, wherein the conductive layer comprises a metal film having a nanometer dimension, a carbon nanotube film, a graphene film, an organic conductive polymer film, an ITO film, or any combination.
The capacitive touch screen of claim 2 or 3, wherein the conductive layer comprises a nanosilver film.
A combination of a capacitive touch screen and a flexible circuit board (FPC), the FPC comprising a plurality of first pins arranged side by side, the capacitive touch screen comprising a substrate and a lead region disposed on the substrate, the lead region comprising a second pin arranged side by side, wherein the width of each second pin is greater than the width of each first pin, and the spacing of adjacent second pins is smaller than the spacing of adjacent first pins, each The two pins are electrically connected to the corresponding one of the first pins.
The combination of claim 6 wherein each of the first pins is intermediate the corresponding one of the second pins.
The combination of claim 6 wherein the capacitive touch screen further comprises a conductive layer disposed on the substrate, the plurality of first leads being formed by the conductive layer by laser.
The capacitive touch screen of claim 6 further comprising a conductive layer disposed on the substrate, the plurality of first leads being formed by the conductive layer by a yellow light process or silk screen.
The combination according to claim 8 or 9, wherein the conductive layer comprises one of a metal thin film having a nanometer dimension, a carbon nanotube film, a graphene film, an organic conductive polymer film, ITO, or any combination thereof.
The combination of claim 8 or claim 9 wherein the conductive layer comprises a nanosilver film.