Share Email Print

Proceedings Paper

Semi-cylindrical LED lamp
Author(s): Akbar Rahmani Nejad; M. A. Olia
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

In this paper, an innovative method to enhance LED lamp beam pattern to more than 180 degrees is provided. The enhancement method is based on the phenomenon of emission of light from a semi-cylindrical surface then there is no absorption of light by optical devices, because there is no implementation of any additional optical devices like lenses, glasses, and diffusers. This is done by mounting LEDs on narrow strips of Electronic boards, and adhering these boards on a T-type fluorescent socket such that to form a semi-cylindrical shape. It is also possible to stick boards to one another such that to make a cylindrical geometry like an ordinary fluorescent lamp but the shape will be odd, screw type socket should be implemented and there will be some disadvantages that make this shape less efficient drastically. This is discussed in the following sections. All optical observations and measurements prove that in the case of semi-cylindrical shape, the light pattern of lamp will be homogenous in more than 180 degree. This is enough homogenous wide angle of light pattern to be used for indoor lighting applications when semi-cylindrical LED lamp is installed on the ceiling or on the wall of room. This method solves the most important drawback of LED lamps that is directional and front-side irritating light of LED lamps. This method is applicable for both common types of LEDs i.e. pin through or surface mounting LEDs, but the first one is more desirable because pin through LEDs will make smaller light-pixels with lower irritating light on semi-cylindrical or cylindrical lamps, i.e. by implementation of cylindrical surface, it is not necessary to use higher diverging specification of surface mounting LEDs (diverging lenses) that in turn it increases fabrication price of such lamps and on the other hand it is not necessary to implement high power LEDs, i.e. cheap high brightness LEDs are ideal for semi-cylindrical LED lamps. The semi-cylindrical shape will maintain a completely wide angle light pattern which will solve the most important problem in the area of application of LED lamps as a uniform-light indoor lamp.

Paper Details

Date Published:
PDF: 11 pages
Proc. SPIE 7422, Ninth International Conference on Solid State Lighting, 742213; doi: 10.1117/12.823430
Show Author Affiliations
Akbar Rahmani Nejad, Independent Researcher (Iran, Islamic Republic of)
M. A. Olia, Independent Researcher (United States)

Published in SPIE Proceedings Vol. 7422:
Ninth International Conference on Solid State Lighting
Ian T. Ferguson; Christoph Hoelen; Jianzhong Jiao; Tsunemasa Taguchi, Editor(s)

© SPIE. Terms of Use
Back to Top