Lens and light emitting module for surface illumination

Abstract

A light emitting module includes a circuit board, a light emitting device mounted on the circuit board, and a lens dispersing light emitted from the light emitting device. The lens includes a lower surface formed with a concave section defining a light incident surface through which light enters the lens, an upper surface through which light exits the lens, and legs coupled to the circuit board and disposed farther outside the lens than an area of the upper surface. The light emitting device is disposed within the concave section of the lens.

What is claimed is: 
     
         1 . A light emitting module comprising:
 a circuit board;   a light emitting device mounted on the circuit board; and   a lens configured to disperse light emitted from the light emitting device,   the lens comprising:   a lower surface comprising a concave section defining a light incident surface through which light enters the lens;   an upper surface through which light exits the lens;   legs coupled to the circuit board at a bottom end thereof;   a flange; and   a plurality of leg supports disposed on a side surface of the flange,   wherein:   the light emitting device is disposed within the concave section of the lens;   the leg supports are coupled to a top portion of the legs;   is a distance between end points of the legs is less than a distance between end points of the leg supports,   the end points of the legs and the end points of the leg supports are points of the legs and the leg supports farthest from a center of the lens, respectively.   
     
     
         2 . The light emitting module according to  claim 1 , wherein each of the leg supports comprises a bottom surface coupled to at least one of the plurality of legs. 
     
     
         3 . The light emitting module according to  claim 1 , wherein the lower surface of the lens comprises a slanted surface and a flat surface. 
     
     
         4 . The light emitting module according to  claim 3 , wherein the flat surface surrounds the concave section and the slanted surface surrounds the flat surface. 
     
     
         5 . The light emitting module according to  claim 3 , further comprising: a reflective sheet disposed on the circuit board, wherein the flat surface is disposed in close contact with the reflective sheet. 
     
     
         6 . The light emitting module according to  claim 3 , wherein the slanted surface has a slope of less than about 10° relative to the circuit board. 
     
     
         7 . The light emitting module according to  claim 3 , wherein the legs are disposed outside the slanted surface. 
     
     
         8 . The light emitting module according to  claim 1 , wherein a width of the leg support is larger than that of an entrance of the concave section. 
     
     
         9 . The light emitting module according to  claim 1 , wherein a width of an entrance of the concave section of the lens is not more than twice a width of the light emitting device. 
     
     
         10 . The light emitting module according to  claim 1 , wherein the light emitting device comprises:
 a light emitting diode chip; and   a wavelength conversion layer disposed on the light emitting diode chip,   wherein the light emitting diode chip is coupled to the circuit board by flip-chip bonding.   
     
     
         11 . The light emitting module according to  claim 1 , wherein the concave section has a height less than a thickness of the flange. 
     
     
         12 . A lens configured to disperse light emitted from a light emitting device, comprising:
 a lower surface comprising a concave section defining a light incident surface through which light enters the lens;   an upper surface through which light exits the lens;   legs configured to be coupled to a circuit board at a bottom end thereof;   a flange; and   a plurality of leg supports disposed on a side surface of the flange,   wherein:   the light emitting device is disposed within the concave section of the lens;   the leg supports are coupled to a top portion of the legs;   a distance between end points of the legs is less than a distance between end points of the leg supports,   the end points of the legs and the end points of the leg supports are points of the legs and the leg supports farthest from a center of the lens, respectively.   
     
     
         13 . The lens according to  claim 12 , wherein each of the leg supports comprises a bottom surface coupled to at least one of the plurality of legs. 
     
     
         14 . The lens according to  claim 12 , wherein the lower surface of the lens comprises a slanted surface and a flat surface. 
     
     
         15 . The lens according to  claim 14 , wherein the flat surface surrounds the concave section and the slanted surface surrounds the flat surface. 
     
     
         16 . The lens according to  claim 14 , wherein the slanted surface is slanted upwards from the flat surface and has a slope of less than about 10° relative to the flat surface. 
     
     
         17 . The lens according to  claim 14 , wherein the legs are disposed outside the slanted surface. 
     
     
         18 . The lens according to  claim 12 , wherein a width of the leg support is larger than that of an entrance of the concave section. 
     
     
         19 . The lens according to  claim 12 , wherein a width of an entrance of the concave section of the lens is not more than twice a width of the light emitting device. 
     
     
         20 . The lens according to  claim 12 , wherein the concave section has a height less than a thickness of the flange.