Patent ID: 8350828

Claim:
A touch screen apparatus comprising: a display screen comprising a display area, a first reflector being a parabolic reflector and having a first focal point, the first reflector disposed outside said display screen and surrounding said display area, a second reflector being a parabolic reflector and having a second focal point, the second reflector disposed outside said display screen and surrounding said display area, the second reflector being opposite to said first reflector, a first infrared light source positioned between the first reflector and the second reflector, and disposed on said first focal point, the first parabolic reflector reflecting an infrared light emitted by the first infrared light source into a parallel infrared light, and the parallel infrared light being reflected by the second parabolic reflector to focus on the second focal point, and an infrared light receiving unit capable of receiving said infrared light in the area of said display screen.