Array of thermally conductive elements in an OLED display

Abstract

An organic light emitting diode (OLED) display includes an array of OLED pixels that generate heat and an array of thermally conductive elements positioned between the OLED pixels and a thermally conductive back panel. In one embodiment of the invention, the thermally conductive elements may be solder joints deposited over cathode contacts and anode contacts at each OLED pixel. The solder joints provide a path of low thermal resistance from the OLED pixels to the back panel. Also, the solder joints may serve as an array of electrical connections from back panel interconnects to the cathode lines and anode lines.

What is claimed is:  
     
         1 . An organic light emitting diode (OLED) display, comprising: 
 a back panel;    a front panel substantially parallel to the back panel;    an array of OLED pixels positioned between the front panel and the back panel; and    a plurality of thermally conductive elements positioned between the OLED pixels and the back panel and distributed throughout the array of OLED pixels, the thermally conductive elements provide a path of low thermal resistance from the OLED pixels to the back panel.    
     
     
         2 . The display of  claim 1 , wherein each OLED pixel comprises a plurality of OLED sub-pixel regions that emit different colors of light.  
     
     
         3 . The display of  claim 1 , wherein the thermally conductive elements comprise solder joints.  
     
     
         4 . The display of  claim 3 , wherein there is at least one solder joint positioned between each OLED pixel and the back panel.  
     
     
         5 . The display of  claim 4 , wherein: 
 each OLED pixel has at least one cathode contact; and    a solder joint for each OLED pixel on the cathode contact between the OLED pixel and the back panel.    
     
     
         6 . The display of  claim 5 , wherein: 
 each OLED pixel has at least one anode contact; and    a solder joint for each OLED pixel on the anode contact between the anode contact and the back panel.    
     
     
         7 . The display of  claim 6 , wherein at least a portion of the solder joints conducts electrical current to the OLED pixels.  
     
     
         8 . The display of  claim 1 , wherein the array of OLED pixels is divided into a plurality of subsets of adjacent pixels.  
     
     
         9 . The display of  claim 8 , wherein there is at least one thermally conductive element positioned between each pixel subset and the back panel.  
     
     
         10 . The display of  claim 9 , wherein: 
 each pixel subset includes an OLED pixel having at least one cathode contact; and    a thermally conductive element for each pixel subset on the cathode contact between the pixel subset and the back panel.    
     
     
         11 . The display of  claim 10 , wherein: 
 each pixel subset includes an OLED pixel having at least one anode contact; and    a thermally conductive element for each pixel subset between the anode contact and the back panel.    
     
     
         12 . The display of  claim 11 , wherein at least a portion of the thermally conductive elements conducts electrical current to the OLED pixels.  
     
     
         13 . The display of  claim 1 , wherein the back panel comprises a ceramic material.  
     
     
         14 . The display of  claim 1 , further comprising an epoxy material to affix the front panel to the back panel such that the epoxy material occupies the space between the thermally conductive elements.  
     
     
         15 . The display of  claim 1 , further comprising a heat fin coupled to the surface of the back panel opposite to the front panel.  
     
     
         16 . The display of  claim 15 , further comprising a cooling fan to force airflow over the heat fin.  
     
     
         17 . An OLED display, comprising: 
 a back panel;    a front panel substantially parallel to the back panel;    an array of OLED pixels positioned between the front panel and the back panel, wherein the array of OLED pixels is divided into a plurality of subsets; and    an array of solder joints distributed throughout the array of OLED pixels such that at least one solder joint is positioned between each pixel subset and the back panel, wherein the solder joints dissipate heat from the OLED pixels and at least a portion of the solder joints conduct electrical current to the OLED pixels.    
     
     
         18 . The display of  claim 17 , wherein the back panel comprises a ceramic material.  
     
     
         19 . The display of  claim 17 , wherein each OLED pixel comprises three OLED sub-pixel regions that emit different colors of light.  
     
     
         20 . The display of  claim 17 , wherein the portion of the solder joints that conduct electrical current are electrically connected to at least one back panel interconnect.  
     
     
         21 . The display of  claim 17 , further comprising a heat fin coupled to the surface of the back panel opposite to the front panel.  
     
     
         22 . The display of  claim 21 , further comprising a cooling fan to force airflow over the heat fin.  
     
     
         23 . A method for manufacturing an OLED display, comprising: 
 providing an array of OLED pixels on a first surface of a front panel;    forming cathode contacts over at least a portion of the OLED pixels and distributed throughout the array of OLED pixels;    forming solder joints on each cathode contact; and    mounting a back panel over the solder joints and substantially parallel to the front panel so that the solder joints provide a path of low thermal resistance from the OLED pixels to the back panel.    
     
     
         24 . The method of  claim 23 , wherein each cathode contact is formed directly over a single OLED pixel.  
     
     
         25 . The method of  claim 23 , wherein the solder joints are formed such that at least a portion solder joints provide electrical current to the OLED pixels.  
     
     
         26 . The method of  claim 25 , wherein the portion solder joints that provide electrical current to the OLED pixels are electrically connected to at least one back panel interconnect.  
     
     
         27 . The method of  claim 23 , further comprising forming anode contacts adjacent to at least a portion of the OLED pixels such that the anode contacts are evenly distributed throughout the array of OLED pixels.  
     
     
         28 . The method of  claim 25 , further comprising forming solder joints on each anode contact throughout the array of OLED pixels.  
     
     
         29 . The method of  claim 23 , further comprising filling the space between the solder joints with an epoxy material to affix the back panel to the front panel.