A METHOD AND SYSTEM FOR DETERMINING THE POINT OF CONTACT OF AN OBJECT WITH A SCREEN

摘要

A system for determining the point of contact of an object with a first side of an at least partially transparent screen (2), the system comprising a radiation source (3) for illuminating the opposite side of the screen to said first side, at least one radiation detecting means (4) for monitoring the radiation reflected from the screen and from any object placed in contact with said first side of the screen, and for producing a signal representative of the monitored image, and signal processing means (5) for processing the signal representative of the monitored image to determine the screen co-ordinates of the or each point of contact of an object with the screen.