US Patent 7375382 Direct optical light guide

An optical light guide has a substantially rigid light transmissive body having an input window, a distal end, a front side, and a rear side. The light transmissive body has a substantially smooth exterior surface on the front side and a substantially clear and solid interior. The input window transmits light into the light transmissive body and extends substantially transverse to a longitudinal axis of a light emitting diode (LED) light source. The light transmissive body has a substantially constant thickness measured between the front side and the rear side. The light transmissive body extends away from the input window through an arc of from 60 to 120 degrees to an extension that forms an output region extending towards the distal end. The rear side, at least in said output region, is formed with a plurality of totally internally reflective steps directing intercepted light towards the front side.