Solid state traffic light apparatus having homogenous light source

摘要

A solid state light apparatus generating a homogenous light beam ideally suited for use in traffic control signals. A solid state light source comprises an area array of LEDs uniformly illuminating a light diffuser to achieve the homogenous light beam. In one embodiment, a plurality of light guides direct light from each LED such that each LED illuminates the same square area of the light diffuser. In another embodiment, the LEDs are provided with lenses having a different radius of curvature such that a convex bottom surface of the light diffuser is uniformly illuminated. The LEDs proximate the center of the array have a smaller radius of curvature than the outer LEDs having flatter lenses.