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| Working principle of touch screen |
| 1, surface acoustic wave screen
The three angles of the sound wave screen are respectively pasted with X, the Y direction of the transmitting and receiving of the acoustic transducer (transducer: made of special ceramic material, which is divided into transmitting transducer and receiving transducer. Is the controller through the touch screen cable sent by the electrical signal into sound energy and the surface acoustic wave by the reflection of the fringes can become the electrical signal. , the reflection of the reflection surface of the reflection of the reflection of the surface of the reflection of the surface is four. When a finger or a soft object touch the screen, the part of the sound energy is absorbed, and then changes the receiving signal, the processing of the controller is obtained by touching the X, Y coordinates.
Four, 2 wire resistive screen
Four wire resistive screen in the surface protective coating and the primary layer between the two layers of transparent conductive layer ITO (ITO: indium oxide, the weak conductivity, the characteristics of the 1800 =10-10 when the thickness of the following will suddenly become transparent, and then a thin down, but the transmittance decreased, 300. Is the main material of all resistance screen and capacitive screen. , the two layer is corresponding to the X, Y axis, which is insulated with fine transparent insulation between the door and the door, when the pressure generated by the touch of the two conductive layer, due to the change in the resistance of the X, Y coordinates.
Five, 3 wire resistive screen
Five wire resistive screen of the base layer of the X, Y two direction of the voltage field in the same layer of transparent conductive layer ITO, the outermost layer of nickel gold conductive layer: only used as a pure conductor, when the contact points X axis and Y axis voltage value of the method to measure the position of the touch point. Inner ITO requires four lead, the outer one, a total of 5 lead wire.
4, capacitive screen
Capacitive screen coated with transparent conductive ITO layer, voltage is connected to the four corners, small DC electric powder Department on the surface of the screen to form uniform electric field, with touch screen, human as the coupling capacitance pole, current from the four corners of the screen together form a capacitive coupling and the other pole, through the controller calculation of power spread to touch position relative distance to get the coordinates of the touch.。 | | | author: Published at: 2014/12/11 11:09:09 |  |
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