Design of a novel TIR lens for optimizing the optical performance of white LED lamps

A novel TIR lens is proposed for optimizing the optical performance of white LED packages. The delineation of a novel TIR lens, including multi-curve collimator and multi-shape surface is determined by the Snell's law, the energy conservation law and the Monte Carlo ray tracking method. It is demonstrated that an optical efficiency of 95.69% under a beam angle of 30 degrees is accomplished by experiments. Furthermore, the illumination homogeneity increases to 0.195 in comparison with the commercial TIR lens uniformity of 0.032. The production cost of this novel lens should be low because it has no a reflector.