Optical coupler and system for distributing light in a 360-degree pattern

摘要

An optical coupler for distributing light in a 360-degree pattern at a small angle is disclosed. The coupler comprises a solid rod with a first end region for receiving light and a second end region for distributing light. The rod tapers up in cross-sectional dimension between the first and second regions so as to decrease the angular distribution of light reflecting internally from the sides of tapered portions of the rod. An axis extends from the second end region towards the first end region. The second end region includes a generally conically shaped void pointing towards the first end region and defining a surface for deflecting light in a 360-degree pattern about the axis at a small angle compared to light entering into the first end region.