Reflective microdisplay for portable communication system

Abstract

The invention relates to a microdisplay system that utilizes a small high resolution active matrix liquid crystal display with an illumination system and a magnifying optical system to provide a display for a portable communication device. A handset for the communication system incorporates the display for use as, for example, a wireless telephone or paging device. The small display can provide a high resolution color image at low power thus providing for portable battery powered operation.

What is claimed is:  
     
         1 . A portable communications device having a reflective display comprising: 
 a device housing having a wireless receiver;    a matrix display;    a lens for viewing the display;    a light source that directs light onto the display; and    an optical coupler that directs the light onto the matrix display and the reflected light through the lens.    
     
     
         2 . The reflective display of    claim 1    wherein the matrix display further comprises an array of pixel elements, each pixel element having transistor circuits formed with single crystal silicon, the pixel element having a reflective pixel electrode.  
     
     
         3 . The reflective display of    claim 2    further comprising a color sequential display circuit.  
     
     
         4 . The reflective display of    claim 3    further comprising a switching circuit connected to a counterelectrode panel of the matrix display for switching the applied voltage.  
     
     
         5 . The reflective display of    claim 3    wherein the light directing device is a dichroic prism interposed between the lens and the matrix display.  
     
     
         6 . A portable communications device having a reflective color sequential display comprising: 
 an active matrix liquid crystal display;    a lens for viewing the display and spaced from the display;    a plurality of light sources that sequentially illuminate the display; and    a dichroic prism for directing the light from the light source to the active matrix liquid crystal display and passing the reflection to the lens.    
     
     
         7 . The device of    claim 6    further comprising a diffuser between the light sources and the dichroic prism.  
     
     
         8 . The device of    claim 7    further comprising at least one dichroic mirror for directing the light from one light source and allowing light from another light source to pass through.  
     
     
         9 . The device of    claim 6    wherein the device comprises a wireless pager.  
     
     
         10 . The device of    claim 6    wherein the device comprises a telephone.  
     
     
         11 . The device of    claim 6    wherein the device comprises a docking station for a wireless telephone.  
     
     
         12 . A portable communications device having a reflective display comprising: 
 an active matrix liquid crystal display having an array of pixel elements, each pixel element having transistors circuits formed with single crystal silicon, the pixel element having a reflective pixel electrode;    a lens for viewing the display and spaced from the display;    a plurality of light emitting diodes;    a dichroic prism for directing the light from the light source to the active matrix liquid crystal display and passing the reflection to the lens.    
     
     
         13 . The device of    claim 12    further comprising a color sequential display circuit.  
     
     
         14 . The device of    claim 12    wherein the matrix display has an array of at least 320 by 240 pixel electrodes.  
     
     
         15 . The device of    claim 12    further comprising a diffuser between the light emitting diodes and the dichroic prism.  
     
     
         16 . The device of    claim 12    further comprising a pair of dichroic mirrors, each mirror for directing the light from one light emitting diode and allowing light from at least another light emitting diode to pass through.  
     
     
         17 . The device of    claim 12    wherein the device comprises a camera.  
     
     
         18 . The device of    claim 12    wherein the device comprises a telephone.  
     
     
         19 . The device of    claim 12    wherein the device comprises a docking station for a telephone.  
     
     
         20 . The device of    claim 12    wherein the device comprises a pager.