Secondary optics is a critical component determining the output efficiency and light distribution of the LED streetlight. A good roadway illumination requires the LED streetlight have a rectangular light pattern just cover the roadway and without excess spill light creeping into yards and shining into windows of neighbor residents. The adoption of the unsymmetrical freeform optics with different light distributions along X and Y directions is necessary. The whole LED streetlight can be constructed if only mounts these LED modules on the planar PCB plate. The mechanism, thermal management, and the power control electronics of the LED streetlight become very simple. In this paper, an optical designapproach of a freeform TIR (total internal reflection) lens for the LED streetlight is investigated. With these freeform lenses, high output efficiency, even light distribution, and batwing far field beam angle distribution can be achieved. k 丹阳市| 五指山市| 什邡市| 和平县| 威宁| 云南省| 伊春市| 井冈山市| 昭平县| 教育| 布拖县| 翼城县| 曲周县| 绥棱县| 阿拉善盟| 定日县| 始兴县| 芦溪县| 神农架林区| 东阿县| 垣曲县| 扬州市| 安仁县| 长泰县| 句容市| 孟津县| 福清市| 邹城市| 清河县| 宝清县| 津南区| 米易县| 商河县| 文安县| 莫力| 石台县| 长治市| 浪卡子县| 安国市| 泰宁县| 沙坪坝区|