English  |  正體中文  |  简体中文  |  Items with full text/Total items : 6491/11663
Visitors : 24733743      Online Users : 48
RC Version 3.2 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Adv. Search

Please use this identifier to cite or link to this item: http://ir.ncue.edu.tw/ir/handle/987654321/10850

Title: Freeform Surface Design for a Light-Emitting-Diode-Based Collimating Lens
Authors: Chen, Jin-Jia;Lin, Chin-Tang
Contributors: 電機工程學系
Keywords: Collimating lens;Freeform surface;Light-emitting diode;Total internal reflection surface
Date: 2010-09
Issue Date: 2012-06-04T08:35:32Z
Publisher: SPIE
Abstract: A freeform collimating lens is designed to project light rays emitted from an LED light source to a far target plane. Generally, the
projection distance is assumed to be more than 100 m, and the light beam to have negligible divergence. The lens consists of a total internal
reflection TIR side surface, a spherical surface in the rear, a vertical plane surface in the outer part of the front, and a freeform refractive
surface in the central part of the front. Light rays emitted from the LED source with large spread angles hit the TIR surface and are redirected
parallel to the light axis, and those having small spread angles will be collimated by the freeform refractive surface, which is designed with a
simple approximation method, and then travel parallel to the light axis. Computer simulation results show that an optical efficiency of 81.5% is
achieved under a view angle of �5 deg and for a 1 mm 1 mm LED source.
Relation: Optical Engineering, 49(9): 093001
Appears in Collections:[電機工程學系] 期刊論文

Files in This Item:

File SizeFormat

All items in NCUEIR are protected by copyright, with all rights reserved.


DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback