Design Of Non - Imaging Discrete Multi - Faceted Free - Form Surface Optical Devices And Its Application In Lighting Applications

The rapid development of high-power LED device provides wide application prospects for both general lighting and special lighting. To take full use of the flux of LED devices, and to provide proper optical solution for certain lighting applications, the research on free-form optical devices based on non-imaging optics has developed rapidly, with the aid of the development of CAD/CAE technology, to realize strict control of beam pattern, precise flux distribution and the high efficiency of the entire illumination fixture. To overcome some bottleneck in the design of free-form optical devices and to improve the performance of the LED lighting fixture, we made research on the design algorithm of free-form optical devices based on multi-discrete optical surfaces, and has achieved the following results:First, we proposed design algorithm of free-form optical devices based on multi-discrete optical surfaces. We conducted the polar equation for Cartesian Oval and introduce Cartesian Oval array to calculate the basic topologic mapping relationship between the source domain and the target domain. By using surface fitting, the smooth topologic mapping relationship can be generated, which is totally different from traditional meshing. Based on the smooth mapping, we built free-form lens in CAD software and made ray-tracing simulation. The simulation results showed great accordance with our expectation.Secondly, we parameterized and optimized the luminous intensity distribution for road lighting based on the luminance factor recommended by CIE. The luminance factor of each individual road light at different position is calculated under a general road lighting application. Through the analysis of the contribution of the luminance on road surface of all road lights, we proposed a two-dimensional illuminance distribution as a composite function of trigonometric functions. With the optimization of all function coefficients, we achieved an optimized illuminance distribution with high overall luminance uniformity, high longitude luminance uniformity, high illuminance uniformity and high luminance/illuminance ratio. The lens model is also designed base on the distribution, and the lighting simulation results can meet the design requirements.Thirdly, we also design two optical system with discrete multi optical surfaces for natural light system and LED driving beam system respectively. The panel-integration based on multi discrete surfaces can achieve collection efficiency of more than41.4%and is compact and feasible to manufacture, while the LED driving beam system can reach the specification requirements in "GB25991-2010Automotive LED headlamp" with merely7.6watts power consumption. For both optical systems, we made prototypes and tested their performance. Both of the testing results can accord with the theoretic calculation, and both systems have promising prospects in real application.