Design And Application Of Collimating Lens For Large-size LED Source

In recent years, more and more countries and industries have spent lots of financial and human resources on LED(Light Emitting Diode) and LED luminaire research and development. Compared with conventional light sources, LEDs have highly concentrated light distribution and very low luminance, so that they need additional optics to improve their optical efficiency and produce prescribed illumination, called secondary optics. Specially, the collimating lens for Large-size LED source like high-power LED source, LED integrated source and LED source array, has many versatile applications to spotlight, flashlight, vehicle headlamps and so on. Therefore, researching the collimating design method for the large-size LED source is particularly urgent. This thesis based on Edge-ray Principle and Snell Law of non-imaging optics researches the collimating design methods for large-size LED source. After classifying and analyzing the previous design methods, some easy and quick design methods for different light shape is proposed. Lenses with round, ellipse, line-shaped and 360° ring-like spots for large-size LED are designed successfully through several simulation and test.About Die-Imaging and Yellow Hue Phenomena: Causes of Die-Imaging and Yellow Hue Phenomena are analyzed. Origin causes are found through simulation and test. Law of Die-Imaging and Yellow Hue Phenomena of several kind lenses are summarized. Several pertinent structure is proposed to Smooth spot and fade Yellow Hue.About round spot: Two pertinent design methods are proposed for plano-convex lens: collimating design method like solving sphere aberration in LightTools software and uniform spot design method called geometry solution. Similarly, two pertinent design methods are proposed for Total Internal Reflect(TIR) lens: division-design method consisted of LightTools software and numerical integral method and method of trial and error for high k value. Meanwhile, total internal reflect phenomena is proved and the importance of k value is expounded. Specially, through twice simulation and test, a collimating lens is designed for full color LED with four die which can mix color perfectly.About regions luminaire with a large aspect ratio: Some normal structure lenses for rectangular spot are analyzed and compared and a lens with one structure in them is designed successfully for the mouth-operation luminaire; The quick division-design method is proposed for line-shaped spot, and a novel arch lens based on TIR structure is designed successfully for the windowsill luminaire by the method; A improved structure lens for low intensity aviation warning luminaire is proposed, which can control light easily and has high optical efficiency compared with previous parabola reflector.About LED source array: Through a great quantity of literature research, combined with luminaire market survey, this thesis emphasizes the appearance and application prospect of LED source array which replaces LED integrate source in many luminaire; A compact novel double-layer TIR lens for Surface Mounted LED of 3×3 array is presented, Die-Imaging and Yellow Hue Phenomena meeting in design process are solved by using structure proposed in LightTools software true color mode. Finally, a color uniform round spot is obtained successfully.We manufacture all lens designed and test it, the actual lighting effects are mostly consistent with the design results, which proves these methods are correct and feasible. All of lens designed are applied in luminaire system.