Semiconductor light emitting device lamp that emits light at large angles

Abstract

Embodiments of the invention include a plurality of semiconductor light emitting diodes attached to a mount. A plurality of lenses are disposed over the plurality of semiconductor light emitting diodes. A lens disposed over a semiconductor light emitting diode proximate an edge of the mount is rotationally asymmetrical and is shaped such that for a portion of the lens light emitted at an intensity that is half a maximum intensity is emitted at an angle of at least 70° relative to a normal to a top surface of the semiconductor light emitting diode.

1 . A structure comprising:
 a plurality of semiconductor light emitting diodes attached to a mount; and   a plurality of lenses disposed over the plurality of semiconductor light emitting diodes, wherein a lens disposed over a semiconductor light emitting diode proximate an edge of the mount is rotationally asymmetrical and is shaped such that for a portion of the lens, light emitted at an intensity that is half a maximum intensity is emitted at an angle of at least 70° relative to a normal to a top surface of the semiconductor light emitting diode.   
     
     
         2 . The structure of  claim 1  wherein a lens disposed over a semiconductor light emitting diode proximate a center of the mount is rotationally symmetrical and is shaped such that light emitted at an intensity that is half a maximum intensity is emitted at an angle less than 70° relative to a normal to a top surface of the semiconductor light emitting diode. 
     
     
         3 . The structure of  claim 1  wherein the lens disposed over a semiconductor light emitting diode proximate an edge of the mount is shaped such that for a portion of the lens, light emitted at an intensity that is half a maximum intensity is emitted at an angle of at least 80° relative to a normal to a top surface of the semiconductor light emitting diode. 
     
     
         4 . The structure of  claim 1  further comprising a shell disposed over the plurality of light emitting diodes, wherein:
 the structure is configured such that light escapes the shell at an angle of 135° relative to a normal to a top surface of the mount; and 
 an amount of light emitted at an angle of 135° relative to a normal to the top surface of the mount is at least 5% of an amount of light emitted at an angle where an intensity of light emitted is at a maximum. 
 
     
     
         5 . The structure of  claim 1  wherein the plurality of lenses comprise silicone lenses molded over the plurality of semiconductor light emitting diodes. 
     
     
         6 . The structure of  claim 1  further comprising a shell disposed over the plurality of semiconductor light emitting diodes. 
     
     
         7 . The structure of  claim 6  wherein the shell comprises a material that causes scattering of light. 
     
     
         8 . The structure of  claim 6  wherein the shell extends below a bottom of the mount. 
     
     
         9 . The structure of  claim 6  wherein the shell and the lens disposed over a semiconductor light emitting diode proximate an edge of the mount are configured such that light escapes the shell at an angle relative to a normal to a top surface of the mount of 135°. 
     
     
         10 . A method comprising:
 forming a plurality of lenses over a plurality of semiconductor light emitting diodes attached to a mount, wherein:   a first lens formed over a first semiconductor light emitting diode has a different shape than a second lens formed over a second semiconductor light emitting diode;   the first semiconductor light emitting diode is located closer to an edge of the mount than the second semiconductor light emitting diode; and   the first lens is rotationally asymmetrical and is shaped such that for a portion of the first lens, light emitted at an intensity that is half a maximum intensity is emitted at an angle of at least 70° relative to a normal to a top surface of the first semiconductor light emitting diode.   
     
     
         11 . The method of  claim 10  wherein the second lens is shaped such that light emitted at an intensity that is half a maximum intensity is emitted at an angle of less than 70° relative to a normal to a top surface of the second semiconductor light emitting diode. 
     
     
         12 . The method of  claim 10  wherein forming a plurality of lenses comprises:
 positioning a mold over the mount, the mold having indentations corresponding to the plurality of semiconductor light emitting diodes; filling a space between the mold and the mount with silicone; and 
 curing the silicone. 
 
     
     
         13 . The method of  claim 10  wherein forming a plurality of lenses comprises forming individual lenses over individual semiconductor light emitting diodes before attaching the plurality of semiconductor light emitting diodes to the mount. 
     
     
         14 . The method of  claim 10  further comprising disposing a shell over the plurality of semiconductor light emitting diodes. 
     
     
         15 . The method of  claim 14  wherein the shell comprises a material that causes scattering of light. 
     
     
         16 . The method of  claim 14  wherein the shell extends below a bottom of the mount. 
     
     
         17 . The method of  claim 14  wherein:
 the shell and the lens disposed over a semiconductor light emitting diode proximate an edge of the mount are configured such that light escapes the shell at an angle relative to a normal to a top surface of the mount of 135°; and 
 an amount of light emitted at an angle of 135° relative to a normal to the top surface of the mount is at least 5% of an amount of light emitted at an angle where an intensity of light emitted is at a maximum.