CN202677362U - Capacitive touch screen - Google Patents
Capacitive touch screen Download PDFInfo
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- CN202677362U CN202677362U CN 201220332218 CN201220332218U CN202677362U CN 202677362 U CN202677362 U CN 202677362U CN 201220332218 CN201220332218 CN 201220332218 CN 201220332218 U CN201220332218 U CN 201220332218U CN 202677362 U CN202677362 U CN 202677362U
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Abstract
The utility model relates to a capacitive touch screen. The capacitive touch screen comprises panel glass, which comprises a touch control area and a wiring area arranged at the edge of the touch control area. The capacitive touch screen also comprises a sensing layer, a ground layer and a driving layer which are sequentially stacked on the touch control area, a first circuit led out from the sensing layer, and a second circuit led out from the driving layer, wherein the first circuit and the second circuit are arranged in the wiring area of the panel glass through overlapping; two capacitors are respectively formed between the driving layer and the ground as well as between the sensing layer and the ground by the ground layer; the change generated by the two capacitors is led out by ground connection, so that the capacitance formed by the sensing layer and the driving layer can be prevented, and the work of the capacitive touch screen is not influenced by the first circuit and the second circuit which are stacked in the wiring area; furthermore, the first circuit and the second circuit are arranged in an overlapped way, so that the wiring space is greatly reduced, the size of the wiring area is reduced, and a frame of the capacitive touch screen is smaller; and therefore, the capacitive touch screen is suitable for the design with a large window and lightweight.
Description
Technical field
The utility model relates to the touch screen technology field, particularly relates to a kind of capacitance touch screen.
Background technology
At present, smart mobile phone is more and more universal, and the display screen of smart mobile phone is toward large-sized trend development.The display screen of mobile phone is large, correspondingly requires the size of mobile phone also increasing.Yet after the size of mobile phone increased to a certain degree, the size of mobile phone was to the portable of mobile phone and handlingly just produce a very large impact.In order to alleviate smart mobile phone giant-screen and portability and handling contradiction, mobile-phone manufacturers and mobile phone touch screen manufacturer have proposed a narrow frame design of new concept-capacitance touch screen.Yet in the wiring zone of existing capacitance touch screen narrow limit design, driving layer can not overlapping cross wire with the circuit of inductive layer.Thereby required wiring space is larger, thereby so that the frame size of capacitance touch screen is larger, can not effectively reduce the physical dimension of mobile phone, is unfavorable for that smart mobile phone is toward large form and lightening future development.
The utility model content
Based on this, being necessary provides a kind of frame less capacitance touch screen for the larger problem of the frame of existing capacitance touch screen.
A kind of capacitance touch screen, comprise face glass, described face glass comprises the Touch Zone and is positioned at the wiring region at edge, described Touch Zone, described capacitance touch screen also comprises inductive layer, ground plane and the driving layer that stacks gradually on described Touch Zone, and first circuit of drawing from described inductive layer and drive second circuit that layer is drawn from described, described the first circuit and the second circuit arranged superposed are in described wiring region.
Therein among embodiment, also comprise being arranged at describedly driving the first adhesive-layer between layer and the ground plane, be arranged at the second adhesive-layer between described ground plane and the inductive layer and be arranged at the 3rd adhesive-layer between described inductive layer and the face glass.
Therein among embodiment, described driving layer, ground plane and inductive layer comprise transparent basement membrane and are laminated in described transparent epilamellar indium tin oxide layer, nano metal layer or carbon nanotube layer, wherein, the transparent basement membrane of the transparent basement membrane of the transparent basement membrane of described driving layer, ground plane and inductive layer all is positioned at the side away from described face glass.
Among embodiment, be provided with circuit on the surface of the indium tin oxide layer of described ground plane, nano metal layer or carbon nanotube layer therein.
Among embodiment, described transparent basement membrane is the polyethylene terephthalate layer therein.
Among embodiment, the described thickness that drives layer, ground plane and inductive layer is 0.05 ~ 0.188 millimeter therein, and the thickness of described face glass is 0.3 ~ 2.0mm, and the thickness of described the first adhesive-layer, the second adhesive-layer and the 3rd adhesive-layer is 0.05 ~ 0.175mm.
Above-mentioned capacitance touch screen is at inductive layer and drive between the layer ground plane is set, and first circuit of drawing from inductive layer and from driving the second circuit arranged superposed that layer draws in the wiring region of face glass.Ground plane forms two electric capacity with the earth so that drive layer respectively with inductive layer, the variation that these two electric capacity produce all is grounded layer and derives, thereby inductive layer and the electric capacity that drives layer formation have been stoped, thereby first circuit and the second circuit arranged superposed can not affect the work of capacitance touch screen, and the first circuit and the second circuit arranged superposed, greatly reduced wiring space, need not to arrange large wiring region to satisfy the wiring demand, therefore the wiring region of face glass is less, so that the frame of capacitance touch screen is less, be conducive to smart mobile phone, the devices such as panel computer are toward large form future development.
Description of drawings
Fig. 1 is the structural representation of the capacitance touch screen of an embodiment;
Fig. 2 is the structural representation of face glass shown in Figure 1;
Fig. 3 is the wire structures schematic diagram of capacitance touch screen shown in Figure 1;
Fig. 4 is the working state schematic representation of capacitance touch screen shown in Figure 1;
Fig. 5 is preparation method's process flow diagram of the capacitance touch screen of an embodiment;
Fig. 6 is the process flow diagram of preparation method's another way of capacitance touch screen shown in Figure 5.
Embodiment
The larger problem of frame for solving existing capacitance touch screen provides a kind of frame less capacitance touch screen.Below further set forth by embodiment and accompanying drawing.
See also Fig. 1, the capacitance touch screen 100 of an embodiment comprises the driving layer 110, the first adhesive-layer 120, ground plane 130, the second adhesive-layer 140, inductive layer 150, the 3rd adhesive-layer 160 and the face glass 170 that stack gradually.
The surface etch of conductive layer has drive pattern, is provided with driver circuit on the drive pattern as the channel electrode lead-in wire that drives layer 110.Driver circuit can be silver electrode lead wires, copper electrode silver line or aluminium contact conductor etc.Draw the second circuit (not shown) from driving layer 110, an end of the second circuit is connected with driver circuit, and the other end stretches out and drives layer 110.
The first adhesive-layer 120 is used for connecting driving layer 110 and ground plane 130.The material of the first adhesive-layer 120 is preferably the OCA optical cement.The OCA optical cement is optically transparent double faced adhesive tape, to guarantee the light transmission of capacitance touch screen 100.And the OCA optical cement does not contain acid, and ito thin film is had no effect.Be appreciated that in other embodiments, the first adhesive-layer 120 also can be the good UV glue-line of light transmission.The viscosity of comprehensive the first adhesive-layer 120 and light transmission, the thickness of the first adhesive-layer 120 are preferably 0.05 ~ 0.175 millimeter.
The second adhesive-layer 140 is used for connecting ground plane 130 and inductive layer 150.The material of the second adhesive-layer 140 is the OCA optical cement.The thickness of the second adhesive-layer 150 is 0.05 ~ 0.175 millimeter.
Be etched with the induction figure on the surface of conductive layer.Be provided with induction line on the induction figure as the channel electrode lead-in wire of inductive layer 150.Induction line can be silver electrode lead wires, copper electrode silver line or aluminium contact conductor etc.Draw the first circuit (not shown) from inductive layer 150.One end of the first circuit is connected with induction line, and the other end stretches out inductive layer 150.
The 3rd adhesive-layer 160 is used for connecting inductive layer 150 and face glass 170.The material of the 3rd adhesive-layer 160 is the OCA optical cement.The thickness of the 3rd adhesive-layer 160 is 0.05 ~ 0.175 millimeter.
The thickness of face glass 170 is 0.30 ~ 2.0 millimeter.Face glass 170 is preferably tempered glass, and the impact strength of tempered glass is higher, so that capacitance touch screen 100 is durable in use.
Preferably, face glass 170 is for the process antistatic treatment, to prevent that capacitance touch screen 100 is by electrostatic breakdown.
Please consult simultaneously Fig. 2, face glass 170 comprises wiring region 172 and Touch Zone 174.Wiring region 172 is positioned at the edge of Touch Zone 174.
The 3rd adhesive-layer 160, inductive layer 150, the second adhesive-layer 140, ground plane 130, the first adhesive-layer 120 and driving layer 110 stack gradually on the Touch Zone 174 of face glass 170.Wherein, the transparent basement membrane of the transparent basement membrane of the transparent basement membrane of driving layer 110, ground plane 130 and inductive layer 150 all is positioned at the side away from face glass 170.
First circuit of drawing from inductive layer 150 with from driving the layer 110 second circuit arranged superposed of drawing in wiring region 172, form circuit 310, as shown in Figure 3.
The principle of work of general capacitance touch screen is identical with the principle of work of capacity plate antenna, can produce electric capacity when overlapping from the circuit that drives circuit that layer draws and draw from inductive layer, change in case touch then have capacitance, the touch-control chip gets final product calculated touch location, therefore non-touch area is that the circuit in the wiring region can not overlapping cross wire, otherwise can affect the work of capacitance touch screen.
The duty of capacitance touch screen 100 as shown in Figure 4, can produce electric capacity when overlapping from the first circuit that drives layer 110 second circuit of drawing and draw from inductive layer 150, but because the existence of ground plane 130, drive and form an electric capacity between layer 110 and the earth, form another electric capacity between inductive layer 150 and the earth, the variation that these two electric capacity produce all is grounded layer 130 and derives, thereby stops driving layer 110 and inductive layer 150 to form electric capacity.Thereby in the situation that the first circuit and the overlapping arranged crosswise of the second circuit, the work of capacitance touch screen 100 can not be affected, and touches non-touch area (being wiring region 172) and can not produce capacitance variation.And because the first circuit and the overlapping arranged crosswise of the second circuit in wiring region 172, so that the wiring space in wiring region 172 of capacitance touch screen 100 reduces greatly than general capacitance touch screen, thereby can reduce the wiring region 172 of face glass 170, so that the frame of capacitance touch screen 100 is less.
The wiring space on wiring region 172 of capacitance touch screen 100 is less, so that the size of wiring region 172 can be done littlely, thereby the Touch Zone 174 of capacitance touch screen 100 is that the viewing area is strengthened, and is conducive to use the electronic products such as smart mobile phone, panel computer of this capacitance touch screen 100 towards the future development of the aobvious form of large scale.
The effect of the ground connection of ground plane 130 will drive that capacity earth that electric capacity that layer 110 and the earth form and inductive layer 150 and the earth form is derived so that from the first circuit of driving layer 110 second circuit of drawing and drawing from inductive layer 150 can arranged superposed in wiring region 172, from practical effect, equal to have increased second layer interference shielding layer, the ability that makes capacitance touch screen 100 overcome interference increases greatly, even whole face is attached on the interference source and all can effectively overcomes interference problem, normal operation.Thereby than general capacitance touch screen, the adaptive capacity to environment of capacitance touch screen 100 can expand the scope that general capacitance touch screen can't work to, and can allow smart mobile phone etc. use the equipment of capacitance touch screen 100 more lightening.
Preferably, the surface of ground plane 130 is provided with the circuits such as copper cash, aluminum steel or silver-colored line, circuit plays a part to accelerate conducting, so that ground plane 130 can be rapidly in time led away driving the electric capacity that forms between the electric capacity that forms between layer 110 and the earth and inductive layer 150 and the earth, further improved the antijamming capability of capacitance touch screen 100.
Please consult simultaneously Fig. 5 and Fig. 6, the preparation method of the capacitance touch screen of an embodiment comprises the steps:
Step S110: face glass 170 is divided into Touch Zone 174 and the wiring region 172 that is positioned at 174 edges, Touch Zone, adopts silk-screen printing technique at wiring region 172 printing-inks.
At first face glass 170 is carried out intensive treatment and make face glass 170 become tempered glass, so that the intensity of face glass 170 is higher, shock resistance is good.The method of the reinforcement of face glass 170 can adopt chemical enhanced method or physical strengthening method.Then the face glass 170 after will strengthening is divided into Touch Zone 174 and is positioned at the wiring region 172 at 174 edges, Touch Zone.Adopt silk-screen printing technique at wiring region 172 printing-inks, in order to when wiring, block circuit.
Step S120: prepare inductive layer 150, and draw the first circuit from inductive layer 150.
Conductive layer away from the surface of transparent basement membrane on etching induction figure.The etching of induction figure can adopt gold-tinted technique etching, silk-screen printing technique or laser ablation technique.
After the induction pattern etching is finished, make induction line at conductive layer with the surface of responding to figure, induction line is as the channel electrode lead-in wire of inductive layer 150.Respond to silver-colored line and can adopt silk-screen printing technique or the preparation of gold-tinted making technology.Induction line connects each passage of induction figure to the winding displacement position.
Offer binding at inductive layer 150 and dodge design, remove by the mode of perforate the position that is about to transparent basement membrane useless on the inductive layer 150, so that wiring.Then in inductive layer 150 wirings, draw the first circuit (not shown) from inductive layer 150.One end of the first circuit is connected with induction line, and the other end stretches out inductive layer 150.
Step S130: preparation ground plane 130.
Preferably, adopt silk-screen printing technique at the circuit of the surface of conductive layer preparation annular.
Step S140: preparation drives layer 110, and draws the second circuit from driving layer 110.
Conductive layer away from the surface of transparent basement membrane on the etching drive pattern.The etching of drive pattern can adopt gold-tinted technique etching, silk-screen printing technique or laser ablation technique.
After the drive pattern etching is finished, make driver circuit at conductive layer with the surface of drive pattern, driver circuit is as the channel electrode lead-in wire that drives layer 110.Driver circuit can adopt silk-screen circuit technique thereof or the preparation of gold-tinted making technology.Driver circuit connects each passage of drive pattern to the winding displacement position.
Step S150: inductive layer 150, ground plane 130 and driving layer 110 are stacked gradually on the Touch Zone 174 of face glass 170, then the first circuit and the second circuit arranged superposed are obtained capacitance touch screen 100 in wiring region 172.
Connect successively inductive layer 150, ground plane 130 and drive layer 110 by viscose glue, driving formation the first adhesive-layer 120 between layer 110 and the ground plane 130, form the second adhesive-layer 140 between ground plane 130 and the inductive layer 150.The first adhesive-layer 120 connects the transparent basement membrane of driving layer 110 and the conductive layer of ground plane 130, and the second adhesive-layer 140 connects the transparent basement membrane of ground planes 130 and the conductive layer of inductive layer 150.
Drive layer the 110, first adhesive-layer 120, ground plane 130, the second adhesive-layer 140 and inductive layer 150 and stack gradually composition composite bed (figure is mark).Then adopting tool that composite bed is carried out sharp processing is complementary with the size and shape with the Touch Zone 174 of face glass 170.
By viscose glue composite bed is layered on the Touch Zone 174 of face glass 170 at last, obtains capacitance touch screen 100, form the 3rd adhesive-layer 160 between composite bed and the face glass 170, then with the first circuit and the second circuit arranged superposed in wiring region 172.Wherein, the screen printing brush finish of face glass 170 stacks by the transparent base membrane layer of the 3rd adhesive-layer 160 with inductive layer 110.
The preparation method of above-mentioned capacitance touch screen, by driving introducing ground plane 130 between layer 110 and the inductive layer 150, and draw the first circuit from inductive layer 150, draw the second circuit from driving layer 110, the first circuit and the second circuit arranged superposed are on the wiring region 172 of face glass 170.Driving variation that two electric capacity that layer 110 and inductive layer 150 form with the earth respectively produce all is grounded layer 130 and derives, thereby inductive layer 150 and the electric capacity that drives layer 110 formation have been stoped, thereby first circuit and the second circuit arranged superposed can not affect the work of capacitance touch screen 100, and the first circuit and the second circuit arranged superposed are in wiring region 172, greatly reduced wiring space, need not to arrange large-sized wiring region to satisfy the wiring demand, thereby the size of the wiring region 172 of face glass 170 is less, so that the frame of capacitance touch screen 100 is less, be conducive to smart mobile phone, the devices such as panel computer are toward large form future development.
Therefore, the preparation method of above-mentioned capacitance touch screen can prepare the less capacitance touch screen of frame, can cater to large form, lightening design.
The above embodiment has only expressed several embodiment of the present utility model, and it describes comparatively concrete and detailed, but can not therefore be interpreted as the restriction to the utility model claim.Should be pointed out that for the person of ordinary skill of the art, without departing from the concept of the premise utility, can also make some distortion and improvement, these all belong to protection domain of the present utility model.Therefore, the protection domain of the utility model patent should be as the criterion with claims.
Claims (6)
1. capacitance touch screen, comprise face glass, it is characterized in that, described face glass comprises the Touch Zone and is positioned at the wiring region at edge, described Touch Zone, described capacitance touch screen also comprises inductive layer, ground plane and the driving layer that stacks gradually on described Touch Zone, and first circuit of drawing from described inductive layer and drive second circuit that layer is drawn from described, described the first circuit and the second circuit arranged superposed are in described wiring region.
2. capacitance touch screen according to claim 1, it is characterized in that, also comprise being arranged at describedly driving the first adhesive-layer between layer and the ground plane, be arranged at the second adhesive-layer between described ground plane and the inductive layer and be arranged at the 3rd adhesive-layer between described inductive layer and the face glass.
3. capacitance touch screen according to claim 1, it is characterized in that, described driving layer, ground plane and inductive layer comprise transparent basement membrane and are laminated in described transparent epilamellar indium tin oxide layer, nano metal layer or carbon nanotube layer, wherein, the transparent basement membrane of the transparent basement membrane of the transparent basement membrane of described driving layer, ground plane and inductive layer all is positioned at the side away from described face glass.
4. capacitance touch screen according to claim 3 is characterized in that, is provided with circuit on the surface of the indium tin oxide layer of described ground plane, nano metal layer or carbon nanotube layer.
5. according to claim 3 or 4 described capacitance touch screens, it is characterized in that, described transparent basement membrane is the polyethylene terephthalate layer.
6. capacitance touch screen according to claim 2, it is characterized in that, the described thickness that drives layer, ground plane and inductive layer is 0.05 ~ 0.188 millimeter, the thickness of described face glass is 0.3 ~ 2.0mm, and the thickness of described the first adhesive-layer, the second adhesive-layer and the 3rd adhesive-layer is 0.05 ~ 0.175mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220332218 CN202677362U (en) | 2012-07-10 | 2012-07-10 | Capacitive touch screen |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220332218 CN202677362U (en) | 2012-07-10 | 2012-07-10 | Capacitive touch screen |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202677362U true CN202677362U (en) | 2013-01-16 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220332218 Expired - Lifetime CN202677362U (en) | 2012-07-10 | 2012-07-10 | Capacitive touch screen |
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| CN (1) | CN202677362U (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103543886A (en) * | 2012-07-10 | 2014-01-29 | 深圳欧菲光科技股份有限公司 | Capacitive touch screen and manufacturing method thereof |
| CN103618283A (en) * | 2013-11-22 | 2014-03-05 | 安徽昌南电气科技有限公司 | Over-current protection device |
| CN104252262A (en) * | 2013-06-26 | 2014-12-31 | 扬升照明股份有限公司 | Touch control module |
| CN104281307A (en) * | 2013-07-10 | 2015-01-14 | 宏达国际电子股份有限公司 | Touch panel |
-
2012
- 2012-07-10 CN CN 201220332218 patent/CN202677362U/en not_active Expired - Lifetime
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103543886A (en) * | 2012-07-10 | 2014-01-29 | 深圳欧菲光科技股份有限公司 | Capacitive touch screen and manufacturing method thereof |
| CN104252262A (en) * | 2013-06-26 | 2014-12-31 | 扬升照明股份有限公司 | Touch control module |
| US9696828B2 (en) | 2013-06-26 | 2017-07-04 | Young Lighting Technology Inc. | Touch module |
| CN104281307A (en) * | 2013-07-10 | 2015-01-14 | 宏达国际电子股份有限公司 | Touch panel |
| CN103618283A (en) * | 2013-11-22 | 2014-03-05 | 安徽昌南电气科技有限公司 | Over-current protection device |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CP01 | Change in the name or title of a patent holder |
Address after: Guangming New District Gongming street Shenzhen city Guangdong province 518106 white pine road o-film Technology Park HUAFA Road Patentee after: Ophiguang Group Co.,Ltd. Address before: Guangming New District Gongming street Shenzhen city Guangdong province 518106 white pine road o-film Technology Park HUAFA Road Patentee before: OFilm Tech Co.,Ltd. |
|
| CP01 | Change in the name or title of a patent holder | ||
| CP03 | Change of name, title or address |
Address after: Guangming New District Gongming street Shenzhen city Guangdong province 518106 white pine road o-film Technology Park HUAFA Road Patentee after: OFilm Tech Co.,Ltd. Address before: Baoan District Gongming town of Shenzhen City, Guangdong province 518106 White Pine Road HUAFA Road Light Technology Park Patentee before: Shenzhen OFilm Tech Co.,Ltd. |
|
| CP03 | Change of name, title or address | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20210422 Address after: 231323 Building 1, precision electronics industrial park, Hangbu Town, Shucheng County, Lu'an City, Anhui Province Patentee after: Anhui jingzhuo optical display technology Co.,Ltd. Address before: Guangming New District Gongming street Shenzhen city Guangdong province 518106 white pine road o-film Technology Park HUAFA Road Patentee before: Ophiguang Group Co.,Ltd. |
|
| TR01 | Transfer of patent right | ||
| CX01 | Expiry of patent term |
Granted publication date: 20130116 |
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| CX01 | Expiry of patent term |