The first "touch sensor" was developed by Doctor Sam Hurst (founder of Elographics) in 1971, while he was an instructor at the University of Kentucky. This sensor called the "Elograph" was patented by The University of Kentucky Research Foundation. The "Elograph" was not transparent like modern touch screens, however, it was a significant milestone in touch screen technology.
However the first true touch screen incorporating a transparent surface came on the scene developed by Sam Hurst and Elographics. Elographics developed and patented five-wire resistive technology lately, the most popular touch screen technology in use today.
