Method and System for Managing Light from a Light Emitting Diode

Abstract

A light source, for example a light emitting diode, can emit light and have an associated optical axis. The source can be deployed in applications where it is desirable to have illumination biased laterally relative to the optical axis, such as in a street luminaire where directing light towards a street is beneficial. The source can be coupled to an optic that comprises an inner surface facing the source and an outer surface that is opposite the inner surface. The inner surface can comprise a refractive surface that receives light headed away from the optical axis of the light source, for example opposite the street. The refractive surface can form the received light into a beam. The outer surface of the optic can reflect the beam back across the optical axis, for example so that light headed away from the street is redirected towards the street.

What is claimed is: 
     
         1 . An optic comprising:
 an inner surface forming a cavity that is configured to receive light from a light emitting diode, the inner surface comprising a plurality of refractive surfaces, each refractive surface configured to produce a respective beam of light from the received light; and   an outer surface that is configured to transmit each of the respective beams of light.   
     
     
         2 . The optic of  claim 1 , wherein the plurality of refractive surfaces have different focal lengths. 
     
     
         3 . The optic of  claim 1 , wherein the plurality of refractive surfaces are disposed adjacent one another. 
     
     
         4 . The optic of  claim 1 , wherein each refractive surface bulges into the cavity. 
     
     
         5 . The optic of  claim 1 , wherein each refractive surface is convex. 
     
     
         6 . The optic of  claim 1 , wherein the plurality of refractive surfaces comprise a first convex surface and a second convex surface,
 wherein the first convex surface and the second convex surface meet one another to form an indentation in the inner surface between the first convex surface and the second convex surface.   
     
     
         7 . The optic of  claim 1 , wherein the plurality of refractive surfaces comprise at least three convex surfaces disposed adjacent one another. 
     
     
         8 . The optic of  claim 1 , wherein the outer surface comprises a plurality of totally internally reflective surfaces corresponding to the plurality of refractive surfaces. 
     
     
         9 . The optic of  claim 1 , wherein the light emitting diode has an optical axis that is disposed in a reference plane, and
 wherein the plurality of refractive surfaces are disposed on one side of the reference plane.   
     
     
         10 . An optic comprising:
 a first surface that is operative to receive light from a light emitting diode disposed adjacent the optic; and   a second surface that opposes the first surface and that is operative to emit the received light,   wherein the first surface comprises:
 a first convex surface that bulges towards the light emitting diode to receive light from the light emitting diode and form a first beam of light; and 
 a second convex surface that is adjacent the first convex surface and that bulges towards the light emitting diode to receive light from the light emitting diode and form a second beam of light. 
   
     
     
         11 . The optic of  claim 10 , wherein the first convex surface has a first focal length and the second convex surface has a second focal length that is different than the first focal length. 
     
     
         12 . The optic of  claim 10 , wherein the first convex surface and the second convex surface meet one another to form an indentation in the first surface between the first convex surface and the second convex surface. 
     
     
         13 . The optic of  claim 10 , wherein the first surface further comprises a third convex surface that is adjacent the second convex surface and that bulges towards the light emitting diode to receive light from the light emitting diode and form a third beam of light, and
 wherein the second convex surface is disposed between the first convex surface and the third convex surface.   
     
     
         14 . The optic of  claim 13 , wherein the first convex surface, the second convex surface, and the third convex surfaces have different focal lengths. 
     
     
         15 . The optic of  claim 10 , wherein the first surface comprises a cavity in which the first convex surface and the second convex surface are disposed. 
     
     
         16 . The optic of  claim 15 , wherein the second surface comprises:
 a first totally internally reflective surface that is aligned with the first convex surface to reflect the first beam of light; and   a second totally internally reflective surface that is aligned with the second convex surface to reflect the second beam of light.   
     
     
         17 . An optic comprising:
 a light-receiving side oriented to receive light from a light emitting diode mounted adjacent the light-receiving side and having an optical axis disposed in a reference plane; and   a light-emitting side that comprises:
 a first region disposed on a first side of the reference plane; and 
 a second region, disposed on a second side of the reference plane, comprising:
 a first protrusion comprising a first internally reflective surface that is oriented to reflect a first portion of the received light passing through the light-receiving side and incident on the first internally reflective surface, so that the reflected first portion of the received light transmits out of the optic through the second region of the light-emitting side and through the reference plane; and 
 a second protrusion comprising a second internally reflective surface that is oriented to reflect a second portion of the received light passing through the light-receiving side and incident on the second internally reflective surface, so that the reflected second portion of the received light transmits out of the optic through the second region of the light-emitting side and through the reference plane. 
 
   
     
     
         18 . The optic of  claim 17 , wherein the first and second protrusions are disposed entirely on the second region of the light-emitting side. 
     
     
         19 . The optic of  claim 17 , wherein the first and second internally reflective surfaces are totally internally reflective, and
 wherein the first protrusion is undercut and the second protrusion is not undercut.   
     
     
         20 . The optic of  claim 17 , wherein the light-receiving side comprises:
 a first convex refractive surface that is configured to form a first beam of light that comprises the first portion of the received light and that is focused towards the first internally reflective surface; and   a second convex refractive surface that is configured to form a second beam of light that comprises the second portion of the received light and that is focused towards the second internally reflective surface.