Backlight system architecture for mobile display system

Abstract

The present invention provides a mobile display system with an improved backlight system. In one embodiment of the invention, the mobile display system comprises a mobile unit including a flat panel display, and a first backlight circuit for providing light to the display. The first backlight circuit includes a plurality of lights sources disposed near edges of the mobile unit and a single power supply for powering a pre-selected one of the light sources. The system also comprises a base station capable of being powered by an external power source. The base station includes a second backlight circuit that comprises at least one power supply for powering the plurality of light sources in the mobile unit when the mobile unit is attached to the base station. This invention keeps the weight and power consumption of the mobile unit low, but allows long battery life at the compromise of display surface light intensity while mobile and provides high brightness characteristics when docked.

What is claimed is:  
     
         1 . A backlight system for use with a mobile display system that includes a mobile unit capable of being powered by a battery and a base station capable of being powered by an external power source, the backlight system comprising: 
 a first circuit in the mobile unit, the first circuit including a plurality of light sources disposed near edges of the mobile unit and a first power supply for powering a pre-selected one of the light sources when operating in a mobile mode of operation; and    a second circuit in the base station, the second circuit including at least a second power supply separate from the mobile unit for powering a plurality of the light sources in the mobile unit when the mobile unit is attached to the base station.    
     
     
         2 . The system of  claim 1 , wherein the second circuit further comprises a plurality of power supplies for powering the plurality of light sources respectively when the mobile unit is attached to the base station.  
     
     
         3 . A mobile display system comprising a mobile unit, the mobile unit including: 
 a flat panel display; and    a first backlight circuit for providing light to the display, the first backlight circuit including a plurality of lights sources disposed near edges of the mobile unit, and a single power supply connected to a pre-selected one of the light sources for powering only the pre-selected light source, the mobile unit being dockable in a base station having a second power supply associated therewith, the docking of the mobile unit in the base station connecting the second power supply to a plurality of the light sources for powering a plurality of the light sources.    
     
     
         4 . The system of  claim 3 , further comprising a base station capable of being powered by an external power source, the base station including a second backlight circuit that comprises at least a second power supply for powering the plurality of light sources in the mobile unit when the unit is attached to the base station.  
     
     
         5 . The system of  claim 4 , wherein the base station further includes a detection mechanism for detecting whether the mobile unit is attached to the base station so as to allow the external power source to power the light sources within the mobile unit.  
     
     
         6 . The system of  claim 5 , wherein the second backlight circuit further comprises a plurality of power supplies for powering the plurality of light sources respectively when the mobile unit is attached to the base station.  
     
     
         7 . The system of  claim 6 , 
 wherein each of the mobile unit and the base station includes at least one electrical connector;    wherein the electrical connectors of the mobile unit and the base station are connected to each other when the mobile unit is attached to the base station.    
     
     
         8 . A backlight system for use with a mobile display system that includes a mobile unit capable of being powered by a battery and a base station capable of being powered by an external power source, the backlight system comprising: 
 a first circuit in the mobile unit, the first circuit including a plurality of light sources disposed near edges of the mobile unit and a single power supply for powering a pre-selected one of the light sources; and    a second circuit in the base station, the second circuit including at least one power supply for powering the plurality of the light sources in the mobile unit when the mobile unit is attached to the base station; and    wherein the second circuit further comprises a plurality of power supplies for powering the plurality of light sources respectively when the mobile unit is attached to the base station.    
     
     
         9 . A mobile display system comprising a mobile unit, the mobile unit including: 
 a flat panel display; and    a first backlight circuit for providing light to the display, the first backlight circuit including a plurality of lights sources disposed near edges of the mobile unit, and a single power supply connected to a pre-selected one of the light sources for powering only the pre-selected light source; and    further comprising a base station capable of being powered by an external power source, the base station including a second backlight circuit that comprises at least one power supply for powering the plurality of light sources in the mobile unit when the unit is attached to the base station; and    wherein the base station further includes a detection mechanism for detecting whether the mobile unit is attached to the base station so as to allow the external power source to power the light sources within the mobile unit.    
     
     
         10 . The system of  claim 9 , wherein the second backlight circuit further comprises a plurality of power supplies for powering the plurality of light sources respectively when the mobile unit is attached to the base station.  
     
     
         11 . The system of  claim 10 , wherein each of the mobile unit and the base station includes at least one electrical connector; 
 wherein the electrical connectors of the mobile unit and the base station are connected to each other when the mobile unit is attached to the base station.    
     
     
         12 . An AC powered base station configured to removably attach to a battery powered mobile, the base station combining with a mobile unit to form an illumination system, the illumination system comprising: 
 a first circuit in the mobile unit, the first circuit including one or more light sources for illuminating a display of the mobile unit, the first circuit being battery powered when unattached to the base station; and    a second AC powered circuit in the base station, including at least one means for illuminating the mobile unit's display when the mobile unit is attached to the base unit.    
     
     
         13 . The base station of  claim 12  wherein the means for illuminating the mobile unit's display is configured to increase the illumination of the display relative to a battery-powered illumination mode for the mobile unit when it is not attached to the base unit.  
     
     
         14 . The base station of  claim 13  wherein the means for increasing the illumination of the mobile unit's display comprises at least one power supply for connecting to the first circuit and powering the one or more light sources in the mobile unit.  
     
     
         15 . The base station of  claim 14 , wherein the second circuit further comprises a plurality of power supplies for powering a plurality of light sources respectively when the mobile unit is attached to the base station.  
     
     
         16 . The base station of  claim 14  further comprising a detection mechanism for detecting whether the mobile unit is attached to the base station so as to allow the external power source to power the light sources within the mobile unit.  
     
     
         17 . The base station of  claim 16  wherein the display is a flat panel display and the plurality of lights sources are disposed near edges of the mobile unit.  
     
     
         18 . The base station of  claim 12  wherein the base unit includes at least one light source, the light source being coupleable to the mobile unit to transmit light to the display when the mobile unit is attached to the base station through a selected surface on the base station, the surface comprising a light transmissive material.  
     
     
         19 . The base station of  claim 18  wherein the light is transmitted into a backlight structure of the mobile unit.  
     
     
         20 . The base station of  claim 18  wherein the base unit is configured so that attaching the mobile unit to the base station switches on power to at least one light source in the base station that transmits light to the mobile unit's display.