A kind of mutual capacitance type touch screen and FPC
Technical field
The utility model relates to touch screen technology, particularly relates to the FPC of a kind of mutual capacitance type touch screen and mutual capacitance type touch screen.
Background technology
Touch-screen is as a kind of input medium, than keyboard and mouse, for the user provides better convenience.According to different realization principles, touch-screen can be divided into resistance-type, condenser type, surface acoustic wave type, infrared type etc.What be widely used at present is resistance-type and capacitive touch screen technology.
Mutual capacitance type touch screen by means of the advantage of its higher sensitivity and the true touch-control of multiple spot, is subject to pursuing of more and more consumers.Mutual capacitance type touch screen is mutually overlapping and consist of electric capacity at overlapping place by drive wire spaced apart and detection line spaced apart.When having n (n refers to the natural number more than 1) bar drive wire and m (m refers to the natural number more than 1) bar to survey line, form altogether m*n electric capacity, need m+n bar line to connect with flexible print circuit board (Flexible Printed circuit is called for short FPC) respectively.
The ultimate principle of mutual capacitance type touch screen is: at drive wire side making alive, surveying line side change in detection signal.Drive wire is determined the X-direction coordinate, surveys line and determines the Y-direction coordinate.When detecting, the X-direction drive wire is lined by line scan, when each row drive wire of scanning, all read every signal of surveying on the line, by a scanning of taking turns, just can scan the intersection point of each ranks, scan altogether m*n signal.This detection mode can be concrete the coordinate of definite multiple spot, therefore can realize multi-point touch.Its equivalent-circuit model as shown in Figure 1, signal source 101, drive wire resistance 103, drive wire and survey mutual capacitance 102 between the line, is surveyed the stray capacitance 104 of line and public electrode interlayer, detection line resistance 105, testing circuit 106 at drive wire.When finger touch, some electric current flows into finger, and equivalence is that the mutual capacitance between drive wire and the detection line changes, and detects the weak current that causes thus in the test side and changes.
Can find out that from the detection principle of mutual capacitance type touch screen the tolerance disturbed of signal is more limited to external world for mutual capacitance type touch screen, so bring the unnecessary interference on the FPC, can affect the touch controllable function of touch-screen greatly.
As shown in Figure 2, the FPC cabling mode of most mutual capacitance type touch screen is side by side cabling of individual layer, drive wire 202 and detection line 203, much design the employing drive wires and survey the modes that line is alternately drawn for fear of the signal that drives on the effect of signals adjacent driven line at the same layer upward wiring.
The defective that prior art exists is, when finger 204 or other metals (for example, application end mainboard metal) when touching FPC, be easy at drive wire and survey produce the effect of putting up a bridge between the line, be equivalent to finger touches on the touch-screen, produce maloperation, the accurate poor-performing of touch-control; In addition, the individual layer side by side mode of cabling has increased to a certain extent touch-screen drive wire 202 and has surveyed mutual capacitance 102 between the line 203, is unfavorable for the input of mutual capacitance type touch screen testing circuit 106.
The utility model content
The purpose of this utility model provides a kind of mutual capacitance type touch screen and is used for the FPC of mutual capacitance type touch screen, in order to solve the technical matters of the easy maloperation of the touch-screen that exists in the prior art, the accurate poor-performing of touch-control.
The FPC of the utility model mutual capacitance type touch screen, the drive wire and the detection line that comprise main body and in two different aspects of main body, arrange respectively.
Preferably, described main body is provided with screen layer between drive wire place aspect and detection line place aspect; Described shielding layer grounding or connect set potential, material is copper.
Described drive wire can be arranged in the top layer of main body, and described detection line is arranged in the bottom of main body; Also can be the top layer that described detection line is arranged in main body, and described drive wire be arranged in the bottom of main body; Described drive wire and described detection line can alternately be arranged in two different aspects of main body respectively.
The utility model mutual capacitance type touch screen comprises:
Such as each described FPC in the above-mentioned technical scheme, be used for drive wire be connected line and be connected with touch screen control circuit.
In the utility model mutual capacitance type touch screen, because drive wire and detection line are arranged in two different aspects of main body respectively, greatly reduced the chance that finger or other metals touch simultaneously the drive wire on the FPC and survey line, thereby reduced the possible maloperation of touch-screen, improved the accurate performance of touch-control.In addition, elimination the has been set drive wire of screen layer and survey the coupling capacitance that produces between the line has also further improved the accurate performance of touch-control.
Below by drawings and Examples, the technical solution of the utility model is described in further detail.
Description of drawings
Fig. 1 is that mutual capacitance type touch screen detects principle schematic;
Fig. 2 is prior art mutual capacitance type touch screen FPC schematic cross-section;
Fig. 3 is the utility model mutual capacitance type touch screen FPC schematic cross-section.
Description of reference numerals:
Mutual capacitance between 101 signal sources, 102 drive wires and the detection line
The stray capacitance of 103 drive wire resistance, 104 drive wires, detection line and public electrode interlayer
105 survey line resistance 106 testing circuits
202 drive wires (prior art)
203 survey line (prior art)
204 fingers, 302 drive wires
303 survey line 304FPC top layer
305FPC middle layer 306FPC bottom
The 307FPC main body
Embodiment
In order to solve the technical matters of the easy maloperation of the touch-screen that exists in the prior art, the accurate poor-performing of touch-control, the utility model provides a kind of mutual capacitance type touch screen and has been used for the FPC of mutual capacitance type touch screen.
For the advantage that makes technical solutions of the utility model is clearer, below in conjunction with accompanying drawing the utility model mutual capacitance type touch screen and the FPC that is used for mutual capacitance type touch screen are done detailed description.Apparently, the accompanying drawing in the following describes only is specific embodiments more of the present utility model, for those of ordinary skill in the art, is not paying under the creationary prerequisite, can also obtain according to these accompanying drawings other accompanying drawing.
As shown in Figure 3, the FPC of the utility model mutual capacitance type touch screen, the drive wire 302 and the detection line 303 that comprise main body 307 and in two different aspects of main body 307, arrange respectively.
Because drive wire and detection line are arranged in two different aspects of FPC respectively, greatly reduce the chance that finger or other metals touch simultaneously the drive wire on the FPC and survey line, thereby reduced the possible maloperation of touch-screen, improved the accurate performance of touch-control.
Preferably in drive wire place aspect on the main body 307 with survey and between the aspect of line place screen layer to be set both are isolated, this shielding layer grounding or connect set potential; The material of screen layer can be identical with the FPC main material, for example is copper, also can be other conducting metals.
In the embodiment shown in fig. 3, drive wire 302 is arranged in main body top layer 304, detection line 303 is arranged in main body bottom 306(and surveys line to be arranged in the main body top layer, and drive wire is arranged in the main body bottom), middle layer 305 is shielding layer grounding (perhaps connecing other set potentials), when finger 204(or other metals) during near FPC, because middle layer 305 ground connection (perhaps connecing other set potentials), so the electric field that sends from drive wire 302 can't arrive by the middle layer and survey line 303, so just disappear except when point 204 when touching FPC on the impact of touch-screen Effect on Detecting.In addition, because middle layer 305 shieldings are arranged between drive wire 302 and the detection line 303, so, coupling capacitance elimination between drive wire 302 and the detection line 303, so just be equivalent to directly reduce the mutual capacitance 102 between drive wire 302 and the detection line 303, highly beneficial for the accurate detection of end of probe testing circuit 106.
Drive wire and detection line can alternately be arranged in two different aspects in main body respectively in the situation that guarantees spacing, also can be arranged in respectively a relative side of two different aspects of main body in the situation that guarantees spacing.
The utility model mutual capacitance type touch screen comprises:
Be positioned at the drive wire of substrate surface;
Be positioned at the detection line of substrate surface, arranged in a crossed manner with drive wire, and can form mutual capacitance at infall with drive wire;
Such as the described FPC of above-mentioned technical scheme, be used for drive wire be connected line and be connected with touch screen control circuit.
Because the drive wire on the FPC of the utility model mutual capacitance type touch screen and detection line are arranged in two different aspects of FPC main body respectively, greatly reduced the chance that finger or other metals touch simultaneously the drive wire on the FPC and survey line, thereby reduced the possible maloperation of touch-screen, improved the accurate performance of touch-control.In addition, the coupling capacitance that elimination has been set produces between the upper drive wire of FPC and the detection line of screen layer has also further improved the accurate performance of touch-control.
Obviously, those skilled in the art can carry out various changes and modification to the utility model and not break away from spirit and scope of the present utility model.Like this, if of the present utility model these are revised and modification belongs within the scope of the utility model claim and equivalent technologies thereof, then the utility model also is intended to comprise these changes and modification interior.