Touch sensitive projection screen

Abstract

An optical device and a projection system incorporating same is disclosed. The optical device includes a light management element. The light management element includes an electrically conductive light absorber that is disposed in a display area for controlling a viewing angle of light transmitted through the display area. The conductive light absorber is configured to generate a signal in response to a touch in the display area. The signal is capable of being used to determine information related to the touch.

What is claimed is: 
     
         1 . An optical device comprising:
 a projection screen capable of displaying an image projected onto the screen and having an electrically conductive light absorber, the light absorber being uniformly electrically conductive across the light absorber; and   an optically transmissive electrically conductive layer facing the screen, wherein the conductive light absorber is configured to generate a signal when a touch causes the conductive light absorber to make an electrical contact with the optically transmissive electrically conductive layer, the signal capable of being used to determine information related to the touch.   
     
     
         2 . A touch sensor comprising one or more electrically conductive light absorbing elements disposed in an optically transmissive touch sensitive area, each element being uniformly electrically conductive and light absorbing across the element, the one or more light absorbing elements being configured to generate a signal in response to a touch applied to the touch sensitive area from a touch side of the touch sensor, the signal capable of being used to determine information related to the touch. 
     
     
         3 . The touch sensor of  claim 2 , wherein the one or more electrically conductive light absorbing elements absorb a substantial portion of light illuminating the touch sensor from the touch side.