Optical lens and light emitting device using the same

Abstract

A light emitting device includes a light-emitting semiconductor unit and an optical lens coupled to the light-emitting semiconductor unit. The optical lens includes a top surface, a base portion opposite to the top surface, and a peripheral side surface defining a first refractive portion. The top surface is generally funnel-shaped. The first refractive portion is corrugated with a plurality of protruding ridge structures, each including a refractive surface.

1 . A light emitting device, comprising:
 a light-emitting semiconductor unit; and   an optical lens coupled to the light-emitting semiconductor unit, the optical lens comprising:   a top surface;   a base portion opposite to the top surface; and   a peripheral side surface defining a first refractive portion corrugated with a plurality of protruding ridge structures, each including a first refractive surface.   
   
   
       2 . The light emitting device as claimed in  claim 1 , wherein the light-emitting semiconductor unit includes a package body disposed adjacent to a bottom of the optical lens and a semiconductor chip fixed on the package body. 
   
   
       3 . The light emitting device as claimed in  claim 2 , wherein the package body includes a protruding portion at an end thereof on which the semiconductor chip is disposed, and the base portion defines a bottom cavity receiving the protruding portion bearing the semiconductor chip thereon. 
   
   
       4 . The light emitting device as claimed in  claim 1 , wherein the peripheral side surface further defines a second refractive portion including a top end adjacent to the top surface and a bottom end adjacent to the second refractive portion. 
   
   
       5 . The light emitting device as claimed in  claim 4 , wherein the second refractive portion is corrugated with a plurality of protruding ridge structures, each including a second refractive surface, symmetrically relative to each of which each of the first refractive surfaces of the first refractive portion is oriented. 
   
   
       6 . The light emitting device as claimed in  claim 4 , wherein the second refractive portion is cylindrical. 
   
   
       7 . The light emitting device as claimed in  claim 6 , wherein the first refractive portion includes a first refractive section and a second refractive section, each including a plurality of ridge structures, each of which has a triangular cross-section, the ridge structures of the first refractive section including a plurality of first refractive surfaces having the same first angle relative to a central axis of the optical lens, the ridge structures of the second refractive section including a plurality of second refractive surfaces having the same second angle relative to the central axis, and the first angle of the first refractive surfaces is different from the second angle of the second refractive surfaces. 
   
   
       8 . The light emitting device as claimed in  claim 1 , wherein the optical lens is made of a transparent material selected from the group consisting of cyclic olefin copolymer, polymethyl methacrylate, polycarbonate, silicone, fluorocarbon polymer, and polyetherimide. 
   
   
       9 . The light emitting device as claimed in  claim 1 , wherein each of the ridge structures has a triangular cross-section, wherein the triangular cross-sections of the ridge structures have the same orientation, and each of the ridge structures includes an angled refractive surface, and the angled refractive surfaces of the ridge structures are angled at the same angle relative to a central axis of the optical lens. 
   
   
       10 . The light emitting device as claimed in  claim 1 , wherein the optical lens further comprises a reflecting sheet above the top surface. 
   
   
       11 . The light emitting device as claimed in  claim 1 , wherein the optical lens further comprises a reflecting film on the top surface.