Light emitting device having a transparent thermally conductive layer

Abstract

A light emitting device and method of producing the same is disclosed. The light emitting device includes a transparent thermally conductive layer, a phosphor layer provided on the transparent thermally conductive layer, wherein the phosphor layer is not enclosed within any layers not containing phosphor, and at least one light emitting semiconductor arranged to emit light toward the transparent thermally conductive layer and the phosphor layer.

1 . An apparatus, comprising:
 a transparent thermally conductive layer;   a phosphor layer provided on the transparent thermally conductive layer, wherein the phosphor layer is not enclosed by the transparent thermally conductive layer; and   at least one light emitting semiconductor arranged to emit light toward the transparent thermally conductive layer and the phosphor layer.   
     
     
         2 . The apparatus of  claim 1 , wherein the phosphor layer comprises a plurality of phosphor sections. 
     
     
         3 . The apparatus of  claim 2 , wherein the phosphor sections are a plurality of separate phosphor patterns. 
     
     
         4 . The apparatus of  claim 2 , wherein each of the phosphor sections comprises a plurality of phosphor layers stacked one on top of another. 
     
     
         5 . The apparatus of  claim 4 , wherein each of the plurality of phosphor layers are stacked in an alternating manner with each of a plurality of transparent thermally conductive layers. 
     
     
         6 . The apparatus of  claim 5 , wherein each of the plurality of phosphor layers are thermally coupled to a heat sink via at least one of the plurality of transparent thermally conductive layers. 
     
     
         7 . The apparatus of  claim 2 , wherein at least one of the phosphor sections is configured to produce light of a color different from that of at least another one of the phosphor sections. 
     
     
         8 . The apparatus of  claim 1 , wherein the transparent thermally conductive layer is formed of a material selected from a group consisting of glass, sapphire, and diamond. 
     
     
         9 . An apparatus, comprising:
 at least one light emitting semiconductor;   a phosphor layer; and   a transparent layer thermally coupled to the phosphor layer, wherein the transparent layer is arranged with the phosphor layer such that light from said at least one light emitting semiconductor passes through the transparent layer to the phosphor layer, and wherein at least a portion of the light output from the phosphor layer does not pass back through the transparent layer.   
     
     
         10 . The apparatus of  claim 9 , wherein the at least one transparent thermally conductive layer and the at least one phosphor layer are stacked in an alternating manner. 
     
     
         11 . The apparatus of  claim 9 , wherein the at least one transparent thermally conductive layer is configured to couple the at least one phosphor layer to a heat sink by a metal housing between the at least one transparent thermally conductive layer and the heat sink. 
     
     
         12 . The apparatus of  claim 11 , wherein the heat sink comprises at least one of a thermal mass and heat dissipating fins. 
     
     
         13 . An apparatus, comprising:
 at least one light emitting semiconductor;   a phosphor layer; and   a transparent layer configured to dissipate heat generated by the phosphor layer, wherein the entire transparent layer is between the phosphor layer and said at least one light emitting semiconductor.   
     
     
         14 . The apparatus of  claim 13 , wherein the phosphor layer comprises:
 at least one phosphor mixture deposited directly on the transparent layer, wherein one of the phosphor mixtures is deposited in a first array of phosphor sections and another one of the phosphor mixtures is deposited in a second array of phosphor sections such that the phosphor sections of the first array do not overlap the phosphor sections of the second array.   
     
     
         15 . The apparatus of  claim 13 , wherein at least one of the phosphor mixtures is configured to produce light of a color different from that of at least another one of the phosphor mixtures. 
     
     
         16 . The apparatus of  claim 14 , wherein the phosphor mixtures have different compositions of phosphor colors. 
     
     
         17 . The apparatus of  claim 13 , wherein the at least one transparent layer is configured to couple the at least one phosphor layer to a heat sink by a metal housing between the least one transparent thermally conductive layer and the heat sink to dissipate heat. 
     
     
         18 . The apparatus of  claim 17 , wherein the heat sink comprises at least one of a thermal mass and heat dissipating fins. 
     
     
         19 . The apparatus of  claim 13 , wherein the transparent layer is formed of a material selected from a group consisting of glass, sapphire, and diamond. 
     
     
         20 . The apparatus of  claim 13 , wherein the at least one transparent layer is configured to couple the at least one phosphor layer to a heat sink by a metal housing between the at least one transparent layer and the heat sink. 
     
     
         21 . The apparatus of  claim 20 , wherein the heat sink comprises at least one of a thermal mass and heat dissipating fins.