Reflection resistant touch screens

Abstract

A flexible, non-birefringent cover and a polarizer on the front of a resistive touch panel reduce touch screen image distortion and obscuration resulting from the reflection of ambient light. Reduced reflection of ambient light is also obtained by touch screens of alternative construction incorporating combinations anti-reflection panels and polarizers located behind the touch panel.

1 . A touch panel comprising: 
 (a) a flexible polarizing element;    (b) a flexible, substantially non-birefringent support element having a first surface bonded to said polarizing element and a conductive second surface; and    (c) a substrate having a conductive surface, said conductive surfaces of said substrate and said support element arranged such that deformation of said support element will cause selective contact of said conductive surfaces.    
   
   
       2 . The apparatus of  claim 1  wherein said flexible, substantially non-birefringent support element comprises a plastic.  
   
   
       3 . The apparatus of  claim 1  wherein said flexible, substantially non-birefringent support element comprises a polycarbonate.  
   
   
       4 . The apparatus of  claim 1  wherein said substrate is substantially non-birefringent.  
   
   
       5 . The apparatus of  claim 1  wherein said flexible, substantially non-birefringent support element comprises triacetate cellulose.  
   
   
       6 . A touch panel comprising: 
 (a) a substrate having a conductive surface    (b) a flexible, substantially non-birefringent cover having a first surface and a conductive second surface, said conductive surfaces of said substrate and said cover arranged such that deformation of said flexible cover will cause selective contact of said conductive surfaces; and    (c) a polarizer supported by said first surface of said cover.    
   
   
       7 . The apparatus of  claim 6  wherein said flexible, substantially non-birefringent cover comprises a plastic.  
   
   
       8 . The apparatus of  claim 6  wherein said flexible, substantially non-birefringent cover comprises a polycarbonate.  
   
   
       9 . The apparatus of  claim 6  wherein said flexible, substantially non-birefringent cover comprises polyvinyl alcohol.  
   
   
       10 . The apparatus of  claim 6  wherein said flexible, substantially non-birefringent cover comprises triacetate cellulose.  
   
   
       11 . The apparatus of  claim 6  wherein said flexible, substantially non-birefringent cover comprises a material having a retardation no greater than 25.  
   
   
       12 . The apparatus of  claim 6  wherein said flexible, substantially non-birefringent cover comprises a material having a retardation no greater than 15.  
   
   
       13 . The apparatus of  claim 6  wherein said flexible, substantially non-birefringent cover comprises a material having a retardation no greater than 5.