The Impact of Fluctuations in Plastic Optical Elements in LED Lamps and Luminaires

Plastics optical elements play an especially important role in the design of modern illumination systems as they are cheap, lightweight, versatile, can incorporate mechanical fixing elements and the optical surface can have nearly any form or shape, which is not the case for glass optics. Despite these advantages over glass optics, plastic optics has some limitations for the design of optical systems. When designing plastics based optical systems, the optics designer has to consider - besides the differences in material properties - the way plastic optical elements are produced. In comparison to glass optics, where the optical properties of the elements are fixed after the melting process and only afterwards the geometrical shape will be finalized by mechanical treatment (except for glass molded or pressed optics), plastic optics will get their optical properties and geometrical shape in one single process: the molding process. This leads to a different way the optics designer has to account for tolerances.