What is Projected Capacitive Touch?
Projected capacitive touch screens (or PCAP touch) are coated with a transparent conductive film (such as ITO) that, when touched by an object (usually the skin on a fingertip), senses the conductive properties of that object.
Capacitive touchscreens can detect multiple points of contact and can also operate while wearing certain types of gloves. They're more responsive than resistive screens when it comes to gestures like swipe and pinch.
What is resistive touch?
Resistive touch screens (or RTP touch) consist of a flexible film upper layer and a rigid lower layer that, when pressed, connect the layers together to complete the circuit and register the touch.
Resistive touchscreens cost less than capacitive touchscreens, but only have a single point of input. Ideal for kiosk applications.
What is Optical Positioning Touch?
Touches are recognized using an optical sensor at the top of the screen, this optical position technology (or IR Touch) relies on infrared LEDs placed on the remaining 3 sides of the display.
The light from the LED is reflected back to the imaging sensor, and when the beam is broken by the touch, a shadow is cast, which records the touch.