Light emitting device

Abstract

A light emitting device includes a wavelength conversion layer, at least one light emitting unit and a reflective protecting element. The wavelength conversion layer has an upper surface and a lower surface opposite to each other. The light emitting unit has two electrode pads located on the same side of the light emitting unit. The light emitting unit is disposed on the upper surface of the wavelength conversion layer and exposes the two electrode pads. The reflective protecting element encapsulates at least a portion of the light emitting unit and a portion of the wavelength conversion layer, and exposes the two electrode pads of the light emitting unit.

What is claimed is: 
     
         1 . A light emitting device, comprising:
 at least one light emitting unit having a light emitting body and electrode pads coupled thereto, wherein each of the electrode pads comprises a second metal layer and a first metal layer interposed between the light emitting body and the second metal layer;   a wavelength conversion layer comprising a high concentration fluorescent layer and a low concentration fluorescent layer disposed thereon;   an adhesive layer adhering the wavelength conversion layer to an upper surface of the light emitting body opposite to the electrode pads and encapsulating a portion of a lateral surface of the light emitting body, wherein the high concentration fluorescent layer faces to the upper surface of the light emitting body; and   a reflective layer, covering the light emitting body, the adhesive layer and the wavelength conversion layer to at least expose an upper surface of the low concentration fluorescent layer and side surfaces and lower surfaces of the second metal layer of the electrode pads, wherein a reflective surface of the reflective layer is inclined to the lateral surface of the light emitting body and reflects a light emitted from the light emitting body back into the high concentration fluorescent layer,   wherein the light emitting device has a flat lateral surface comprising the reflective layer and a portion of the low concentration fluorescent layer covering the reflective layer, and the adhesive layer further comprises a portion disposed directly between the high concentration fluorescent layer and the light emitting body.   
     
     
         2 . The light emitting device as claimed in  claim 1 , wherein the reflective surface of the reflective layer comprises a convex surface or a concave surface. 
     
     
         3 . The light emitting device as claimed in  claim 1 , wherein the lower surface of the reflective layer is not lower than a bottom surface of the light emitting body. 
     
     
         4 . The light emitting device as claimed in  claim 3 , wherein the lower surface of the reflective layer is inclined to the lateral surface of the light emitting body and recessed upwardly. 
     
     
         5 . The light emitting device as claimed in  claim 1 , wherein the lower surface of the reflective layer is inclined to the lateral surface of the light emitting body and recessed upwardly. 
     
     
         6 . The light emitting device as claimed in  claim 1 , wherein the reflective layer further exposes the first metal layers of the electrode pads. 
     
     
         7 . The light emitting device as claimed in  claim 6 , wherein a portion of the reflective layer is filled into a gap between the electrode pads. 
     
     
         8 . The light emitting device as claimed in  claim 6 , wherein the lower surface of the reflective layer is inclined to the lateral surface of the light emitting body and recessed upwardly. 
     
     
         9 . The light emitting device as claimed in  claim 8 , wherein a portion of the reflective layer is filled into a gap between the electrode pads. 
     
     
         10 . The light emitting device as claimed in  claim 1 , wherein a portion of the reflective layer is filled into a gap between the electrode pads. 
     
     
         11 . A light emitting device, comprising:
 at least one light emitting unit having a light emitting body and electrode pads coupled thereto, wherein each of the electrode pads comprises a second metal layer and a first metal layer interposed between the light emitting body and the second metal layer;   a wavelength conversion layer comprising a high concentration fluorescent layer and a low concentration fluorescent layer disposed thereon;   an adhesive layer adhering the high concentration fluorescent layer to an upper surface of the light emitting body opposite to the electrode pads, wherein the adhesive layer encapsulates the upper surface and a portion of a lateral surface of the light emitting body; and   a reflective layer covering the light emitting body, the adhesive layer and the wavelength conversion layer to expose an upper surface of the low concentration fluorescent layer and be filled into a gap between the electrode pads, the second metal layers of the electrode pads protruding from a lower surface of the reflective layer, wherein a reflective surface of the reflective layer is inclined to the lateral surface of the light emitting body and reflects a light emitted from the light emitting body back into the high concentration fluorescent layer,   wherein the light emitting device has a flat lateral surface comprising the reflective layer and a portion of the low concentration fluorescent layer covering the reflective layer, and the lower surface of the reflective layer is inclined to the lateral surface of the light emitting body and recessed upwardly.   
     
     
         12 . The light emitting device as claimed in  claim 11 , wherein the reflective surface of the reflective layer comprises a convex surface or a concave surface. 
     
     
         13 . The light emitting device as claimed in  claim 11 , wherein the lower surface of the reflective layer is not lower than a bottom surface of the light emitting body. 
     
     
         14 . The light emitting device as claimed in  claim 11 , wherein the reflective layer further exposes the first metal layers of the electrode pads. 
     
     
         15 . A light emitting device, comprising:
 at least one light emitting unit having a light emitting body and electrode pads coupled thereto, wherein each of the electrode pads comprises a second metal layer and a first metal layer interposed between the light emitting body and the second metal layer;   a wavelength conversion layer disposed on the light emitting body;   an adhesive layer adhering the wavelength conversion layer to an upper surface of the light emitting body opposite to the electrode pads, wherein the adhesive layer encapsulates the upper surface and a portion of a lateral surface of the light emitting body; and   a reflective layer covering the light emitting body, the adhesive layer and the wavelength conversion layer to expose an upper surface of the wavelength conversion layer and be filled into a gap between the electrode pads, the second metal layers of the electrode pads protruding from a lower surface of the reflective layer, wherein a curved reflective surface of the reflective layer is inclined to the lateral surface of the light emitting body and reflects a light emitted from the light emitting body back into the wavelength conversion layer,   wherein the light emitting device has a flat lateral surface comprising the reflective layer and a portion of the wavelength conversion layer covering the reflective layer, and the lower surface of the reflective layer is inclined to the lateral surface of the light emitting body and recessed upwardly.   
     
     
         16 . The light emitting device as claimed in  claim 15 , wherein the curved reflective surface of the reflective layer comprises a convex surface or a concave surface. 
     
     
         17 . The light emitting device as claimed in  claim 15 , wherein the lower surface of the reflective layer is not lower than a bottom surface of the light emitting body. 
     
     
         18 . The light emitting device as claimed in  claim 15 , wherein the reflective layer further exposes the first metal layers of the electrode pads. 
     
     
         19 . The light emitting device as claimed in  claim 15 , wherein the wavelength conversion layer comprises a high concentration fluorescent layer and a low concentration fluorescent layer disposed thereon. 
     
     
         20 . The light emitting device as claimed in  claim 15 , wherein the second metal layer comprises silver, gold, bismuth, tin, indium or an alloy thereof.