Touch panel, display device provided with touch panel and electronic equipment provided with display device

Abstract

A touch panel using an optical sensor has a simple construction and can accurately detect an input position. An illuminating lights emitted from illuminating means are turned into lights having a high directivity in an X-axis direction and in a Y-axis direction of the prism lens sheet and thereafter enter from side faces of a light guide panel as incident lights. The incident lights advance in the inside of the light guide panel toward opposite side faces while being subjected to a total reflection and are received by the optical sensor arrays. When an input pen or a fingertip touches a surface of the light guide panel, the lights are refracted or absorbed at a touched position and hence, a quantity of received lights at the optical sensor arrays is reduced.

1 . A display device including a touch panel and a display portion, the display device comprising:
 an optical sensor;   a light source;   a reflection sheet surrounding the light source; and   a light guide panel which propagates a light emitted from the light source,   wherein the light source and the reflection sheet are provided so that the light guide panel is irradiated with the light emitted from the light source,   wherein the light source is provided between the reflection sheet and the light guide panel, and   wherein the display portion comprises an interlayer insulating film made of a resin material and a pixel electrode provided over the interlayer insulating film.   
   
   
       2 . The display device according to  claim 1 , wherein a refractive index of the light guide panel is 1.4 to 1.7. 
   
   
       3 . An information terminal mounting the display device according to  claim 1 . 
   
   
       4 . A display device including a touch panel and a display portion, the display device comprising:
 an optical sensor;   a light guide panel including a translucent material;   a light emitting diode provided on a side surface of the light guide panel; and   a lens sheet provided between the light guide panel and the light emitting diode,   wherein the light guide panel propagates a light emitted from the light emitting diode.   
   
   
       5 . The display device according to  claim 4 , wherein the lens sheet has a plurality of prismatic or semicylindrical protrusions. 
   
   
       6 . The display device according to  claim 4  wherein a refractive index of the translucent material is 1.4 to 1.7. 
   
   
       7 . An information terminal mounting the display device according to  claim 4 . 
   
   
       8 . A display device including a touch panel and a display portion, the display device comprising:
 an optical sensor;   a liquid crystal panel;   a light guide panel including a translucent material provided on one surface of the liquid crystal panel;   a light emitting diode provided on a side surface of the light guide panel; and   a lens sheet provided between the light guide panel and the light emitting diode,   wherein the light guide panel propagates a light emitted from the light emitting diode.   
   
   
       9 . The display device according to  claim 8 , wherein the lens sheet has a plurality of prismatic or semicylindrical protrusions. 
   
   
       10 . The display device according to  claim 8 , wherein a refractive index of the translucent material is 1.4 to 1.7. 
   
   
       11 . An information terminal mounting the display device according to  claim 8 . 
   
   
       12 . A display device including a touch panel and a display portion, the display device comprising:
 a liquid crystal panel;   an optical sensor provided not to overlap the liquid crystal panel;   a light guide panel including a translucent material provided to overlap the liquid crystal panel;   a lens sheet adjacent to the light guide panel; and   a light emitting diode provided so as to be propagated by the light guide panel.   
   
   
       13 . The display device according to  claim 12 , wherein the lens sheet has a plurality of prismatic or semicylindrical protrusions. 
   
   
       14 . The display device according to  claim 12 , wherein a refractive index of the translucent material is 1.4 to 1.7. 
   
   
       15 . An information terminal mounting the display device according to  claim 12 .