Glass substrate, transparent metal oxide coating
Principle of Operation
- Voltage is applied to the corners of the touch screen.
- A pattern of electrodes around the periphery of the touch screen distribute the voltage to form a uniform electric field across the conductive surface.
- A finger touch draws a minute amount of current from the surface and is measured by the controller.
- The relative magnitude of current is inversely proportionate to the distance from the contact point to the touch screen corners.
- Ratios of the four corner currents are calculated to determine the X, Y coordinate.
Pros and Cons
|Withstands contaminants and moving liquids on the screen and keeps working across the entire touchscreen surface||Supports only finger or tethered pen|
|Very light finger touch required for activation||Severe scratch can affect operation within the damaged area|
|Technology with fastest touch response time||Limited to 1 resolvable point with gesture capability|
|Transmission typically 88 % to 9 2%|
Content and images of 3M were reproduced with permission © 3M 2010. All rights reserved.