Microstructure Optics Designed for LED Traffic Signal Lighting

Abstract

Optical lenses are used in signal lighting to control intensity distributions. Brightness and viewing angle are two essential requirements that have to be considered in manufacturing a traffic signal lamp. This paper discusses design considerations for microstructure optics designed for LED traffic signal light, strategies for obtaining particular intensity distributions, optical functions of the lens and matters concerning the manufacturing process. The mould inserts of the optical surfaces were machined by CNC high-speed milling. Results of surface finish and profile accuracy analyses using the Form Talysurf instrument are presented.