Additionally, as only sufficient pressure is necessary for the touch to be sensed, they may be used with gloves on, or by using anything rigid as a finger substitute. Although some standard Capacitance detection methods are projective, in the sense that they can be used to detect a finger through a non-conductive surface, they are very sensitive to variations in temperature, which expand or contract the sensing plates.

Archived at the Wayback Machine. It only takes 2 minutes to place your order over the phone with us. In , a group at the University of Illinois filed for a patent on an optical touchscreen [14] that became a standard part of the Magnavox Plato IV Student Terminal and thousands were built for this purpose.

Infrared touchscreens are sensitive to dirt and dust that can interfere with the infrared beams, and suffer from parallax in curved surfaces and accidental press when the user hovers a finger over the screen while searching for the item to be selected. Click Touch Pointer Test first. When the Startup menu appears, press F2.