Patent ID: 8351125
Filing Date: 2013-01-08
Classification: G02B

Abstract:
1. A directional light distributing optical element, for receiving a light emitted by a light source comprising an optic axis, the directional light distributing optical element comprising: a light incident surface, for receiving the light and comprising a central axis; and a light emission curved surface, intersected with a first plane being vertical to the central axis to form a first curve, wherein the first curve has a plurality of first curve segments, each first curve segment comprises at least three first tangent points, and after passing each first tangent point along a connecting line of the light source and each first tangent point, the light exits along a first axis, an included angle formed between the first axis and the optic axis is greater than −15° and smaller than 15°, and each first tangent point satisfies a formula in the following: wherein M