Led assembly with omnidirectional light field

Abstract

Disclosed is an LED assembly having an omnidirectional light field. The LED assembly has a transparent substrate with first and second surfaces facing to opposite orientations respectively. LED chips are mounted on the first surface and are electrically interconnected by a circuit. A transparent capsule with a phosphor dispersed therein is formed on the first surface and substantially encloses the circuit and the LED chips. First and second electrode plates are formed on the first or second surface, and electrically connected to the LED chips.

What is claimed is: 
     
         1 . A light emitting diode assembly, comprising:
 a transparent substrate, comprising first and second surfaces facing to opposite orientations respectively;   light emitting diode chips, mounted on the first surface;   a circuit electrically connecting the light emitting diode chips;   a transparent capsule with a phosphor dispersed therein, formed on the first surface and substantially enclosing the circuit and the light emitting diode chips; and   first and second electrode plates, formed on the first or second surface, and electrically connected to the light emitting diode chips.   
     
     
         2 . The light emitting diode assembly as claimed in  claim 1 , wherein the transparent capsule comprises a transparent adhesive layer having a first phosphor dispersed therein, and placed between at least one of the light emitting diode chips and the transparent substrate. 
     
     
         3 . The light emitting diode assembly as claimed in  claim 2 , wherein the transparent capsule comprises transparent adhesive layers, and the light emitting diode chips are mounted one-on-one on the transparent adhesive layers. 
     
     
         4 . The light emitting diode assembly as claimed in  claim 2 , wherein the transparent capsule has a single transparent adhesive layer, and all the light emitting diode chips in the light emitting diode assembly are mounted on the transparent adhesive layer. 
     
     
         5 . The light emitting diode assembly as claimed in  claim 2 , wherein the transparent capsule has a transparent body covering on and surrounding the light emitting diode chips, and the transparent body has a second phosphor dispersed therein. 
     
     
         6 . The light emitting diode assembly as claimed in  claim 2 , further comprising a submount placed under the light emitting diodes and on the transparent adhesive layer. 
     
     
         7 . The light emitting diode assembly as claimed in  claim 6 , wherein the light emitting diode chips are mounted on the submount by way of flip chip technique. 
     
     
         8 . The light emitting diode assembly as claimed in  claim 1 , wherein the circuit comprises a bonding wire electrically connecting two of the light emitting diodes. 
     
     
         9 . The light emitting diode assembly as claimed in  claim 1 , wherein the transparent substrate is substantially in the form of a longitudinal strip having two opposite ends, and the first and second electrode plates are placed on the first and second surfaces respectively and nearby one common end of the two opposite ends. 
     
     
         10 . The light emitting diode assembly as claimed in  claim 1 , wherein the transparent substrate is substantially in the form of a longitudinal strip having two opposite ends, and the first and second electrode plates are placed nearby the two opposite ends respectively. 
     
     
         11 . A method for manufacturing a LED assembly, comprising:
 providing a transparent substrate, having first and second surfaces facing the opposite orientations;   mounting LED chips on the first surface using at least one transparent adhesive layer, wherein the transparent adhesive layer has a phosphor dispersed therein;   forming a circuit one the first surface for interconnection between the LED chips; and   forming a transparent body covering on and surrounding the LED chips, wherein the transparent body has a first phosphor dispersed therein.   
     
     
         12 . The method as claimed in  claim 11 , wherein comprising:
 mounting the LED chips on the first surface using two transparent adhesive layers;   wherein at least one of the two transparent adhesive layers has a second phosphor, the other has no phosphor, and the two transparent adhesive layers stack between one of the LED chips and the transparent substrate.   
     
     
         13 . The method as claimed in  claim 11 , further comprising:
 mounting the LED chips on a submount; and   mounting the submount on the first surface of the transparent substrate.   
     
     
         14 . The method as claimed in  claim 13 , comprising:
 forming the at least one transparent adhesive layer on a backside of the submount; and   fixing both the submount and the transparent adhesive layer on the first surface.   
     
     
         15 . The method as claimed in  claim 13 , wherein the LED chips are mounted on the submount by way of flip chip technique. 
     
     
         16 . The method as claimed in  claim 11 , wherein the transparent substrate comprises a via hole tunneling therethrough and the via hole is formed with conductive material therein to provide a conductive via, the method comprising:
 forming a first electrode plate on the first surface; and   forming a second electrode plate on the second surface, wherein the second electrode plate contacts the conductive via;   wherein the LED chips and the conductive via are connected in series between the first and second electrode plate.   
     
     
         17 . The method as claimed in  claim 11 , wherein the transparent substrate is substantially in the form of a longitudinal strip having two opposite ends, and the method further comprises forming first and second electrode plates on the first and second surfaces respectively and nearby one common end of the two opposite ends. 
     
     
         18 . The method as claimed in  claim 11 , wherein the transparent substrate is substantially in the form of a longitudinal strip having two opposite ends, and the method further comprises forming first and second electrode plates nearby the two opposite ends respectively and on the first surface. 
     
     
         19 . The method as claimed in  claim 11 , wherein the transparent substrate is substantially in the form of a longitudinal strip having two opposite ends, and the method further comprises forming first and second electrode plates nearby the two opposite ends respectively and on the second surface. 
     
     
         20 . The method as claimed in  claim 11 , wherein the transparent substrate is substantially in the form of a longitudinal strip having two opposite ends, and the method further comprises forming first and second electrode plates on the first surface and nearby one common end of the two opposite ends.