Patent ID: 8944660
Filing Date: 2015-02-03
Classification: F21V,F21Y,G02B

Abstract:
1. A light guide for modifying a light distribution pattern of a light source, the light guide comprising a transparent element made of transparent material having refractive index greater than unity and the transparent element comprising: a first end comprising a place for the light source, a second end opposite the first end, an outer surface between the first and second ends, and an interior channel free from the transparent material and extending from the first end to the second end, wherein the interior channel comprises a first portion beginning from the first end and a second portion extending to the second end, the first portion being shaped to guide at least part of light falling to a wall of the first portion into the transparent material and towards the outer surface, and the outer surface being shaped to provide total reflection for reflecting the at least part of the light towards the second end, and wherein the second portion is at least as long as the first portion, and the second portion is shaped so that: where L is a distance from the first end, W is a width of the interior channel at the distance L from the first end, L wherein the wall of the first portion of the interior channel defines a truncated cone.