A touchscreen is a screen that is sensitive to the touch of a finger or stylus and can be found in many things we use on a daily basis e.g. car navigation systems and portable had held devices such as cell phones. It relies on sensors to pick up the location of a pointing device, whether it’s your fingertip or a stylus. There are three components used in touch screen technology: * The touch sensor a panel with a touch responsive surface. Different types of sensors: resistive, surface acoustic wave, and capacitive. Sensors have an electrical current running through them and touching the screen causes a voltage change. The voltage change signals the location of the touching. * The controller, is the hardware that converts the voltage changes on the sensor into signals the computer or other device can receive. * Software tells the computer, smartphone etc, what is being done on the sensor and the information coming from the controller. Who 's touching what where; and allows the computer or smart phone to react accordingly.
There are two (2) main types of touchscreen technologies, resistive and capacitive.
Resistive technology employs narrowly separated layers of conductive material, usually glass and a plastic film that react to the location of the contact. The glass and plastic film are each covered with a grid of electrical conductors. These can be made of a thin film of transparent conductor material. There are electrodes on the two layers run at right angles to each other (parallel conductors run in one direction on the glass sheet and at right angles to those on the plastic film). When you press down on the touch screen, contact is made between the grid on the glass and the grid on the film. The
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