The touch
screen was derived from the digitizing tablet. The digitizing tablet was
invented by Sam Hurst in 1971. It was designed to allow scientists to record
data from graphs by placing the graph on the tablet and pressing the paper
against the tablet with a stylus. A touch screen sensor is a clear glass panel with a touch responsive
surface. The touch sensor/panel is placed over a display screen so that the
responsive area of the panel covers the viewable area of the video screen.
There are several different touch sensor technologies on the market today, each
using a different method to detect touch input. The sensor generally has an
electrical current or signal going through it and touching the screen can cause
a voltage or signal change. This change is used to determine the location of
the touch to the screen. The
controller connects between the touch sensor and the PC. It takes information
from the touch sensor and translates it into information that PC can
understand. The controller determines what type of interface/connection you
will need on the PC. Controllers are available that can connect to a Serial/COM
port (PC) or to a USB port. Specialized controllers are also available that
work with DVD players and other devices.
