Patent ID: 9689553
Date: 2017-06-27
CPC Classifications: F21V,F21Y,G02B

Claim:
1. A lens comprising: a light emergent surface formed on one side of the lens; a bottom surface being on an opposite side of the lens to the light emergent surface and a recess being formed in the bottom surface; a light incident surface formed on the recess by a plurality of ring-shaped curved surfaces connected to each other, the curved surfaces directly connected to each other to form a plurality of connecting curves; wherein the lens defines a groove formed on a top portion of the light incident surface, the groove extends from the top portion of the light incident surface toward the bottom surface and narrows to a point from the top surface toward the bottom surface, a cross-sectional view of a bottom portion of the groove being an isosceles triangle, and the point of the groove lying on a center axis of the lens.