Patent ID: 9631790
Date: 2017-04-25
CPC Classifications: F21K,F21V,F21W,F21Y,F25D,G02B

Claim:
1. An illumination lens, comprising: a light incident surface that defines a cavity and comprises a top surface and lateral flanks, the light incident surface configured to receive light from an underlying light emitting element; a light exiting surface comprising a central indentation and surrounding toroid; and a bottom surface connecting the light incident surface and the light exiting surface, wherein: the lateral flank comprises a first region extending from the top surface and a second region extended from the first region; the second region is a curved surface, of which the center of the curvature thereof lies on the illumination lens, an intersection of the second region and a horizontal optical axis forms a first point; and the first point is disposed lower than a second point where the bottom surface and the light exiting surface intersect.