Adding an extra condition: a general method to design double freeform-surface lens for LED uniform illumination

Abstract

Uniform illumination is an essential optical requirement for light-emitting diode (LED) applications. In this paper, a general method was proposed to design double freeform-surface lenses for uniform illumination of LED packages. Detailed algorithms of the design method were presented, in which the inner and outer surfaces of the lenses could be designed simultaneously. This problem can't be solved unless providing an extra condition. Two kinds of extra conditions were introduced to design the lens and validate the method. Besides uniform illumination, the present method can also realize extra functions with providing different extra conditions, like conformal phosphor coating and minimum Fresnel loss. The present method can be extended to design various freeform-surface lenses for LED uniform illumination provided that different conditions are added based on different application requirements.

LED packaging for high light quality: Status and perspectives

“…对于阵列LED模块. Zhang和 Lee [130] 通过在基板上加工微槽来限制封装胶的流动, 从而得到和基板之间具有较大接触角的晶圆级荧光 粉涂覆方法; Yu等人 [131] [117,118,134,135] . 针对于扩展光源, Munon等人 [137] 和Benitez等人 [138] 于2004年提出多曲面同时设计法 ( [154] .…”

LED secondary light distribution design based on grid division method

“…Compared with traditional incandescent lamps, CFLs can save 4/5 energy [1] , but LEDs are 1/4 more energy efficient than CFLs [2] . LEDs are recognized as the fourth lighting revolution after incandescent, fluorescent, and high-intensity discharge lamps [3] . The market demand for high uniformity lighting is increasing [4] , for commercial lighting, outdoor lighting, road lighting and other market sectors focus on the high uniformity of lighting spot [5] .…”