A touch screen is an electronic visual display that can detect presence and location of touch within the display area...
It is a two dimensional sensing device that is made of two sheets of material separated by small spacers. There are three main touch screen technologies viz., resistive, capacitive and surface acoustic wave. Here i will discuss about resistive touch screen
Resistive touch screen:
The resistive touch screen consists of flexible top layer made of polythene and rigid bottom layer made of glass. Both the layers are spaced with spacers and are coated with indium tin oxide. When the screen is operating a small current flows in between the space. When a touch is made, the flexible screen presses down to touch the glass layer. A change in current is hence detected and coordinates of the point of touch calculated by the controller and parsed into readable signal for the operating system to react accordingly.
The four-wire resistive touch screen uses both the layers to calculate the axes information of the touch. Touch measurement is a two-step process. The x-coordinate of the touch point is calculated by creating a voltage gradient on flexible layer, and the y-coordinate is determined by creating a voltage gradient along the bottom layer.
It is a two dimensional sensing device that is made of two sheets of material separated by small spacers. There are three main touch screen technologies viz., resistive, capacitive and surface acoustic wave. Here i will discuss about resistive touch screen
Resistive touch screen:
The resistive touch screen consists of flexible top layer made of polythene and rigid bottom layer made of glass. Both the layers are spaced with spacers and are coated with indium tin oxide. When the screen is operating a small current flows in between the space. When a touch is made, the flexible screen presses down to touch the glass layer. A change in current is hence detected and coordinates of the point of touch calculated by the controller and parsed into readable signal for the operating system to react accordingly.
The four-wire resistive touch screen uses both the layers to calculate the axes information of the touch. Touch measurement is a two-step process. The x-coordinate of the touch point is calculated by creating a voltage gradient on flexible layer, and the y-coordinate is determined by creating a voltage gradient along the bottom layer.
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