Open AccessLED beam shaping lens based on the near-field illumination
Author(s) -
Jae Young Joo,
Chang Seog Kang,
Soon Sub Park,
Sun-Kyu Lee
Publication year - 2009
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.023449
Subject(s) - optics , total internal reflection , light emitting diode , lens (geology) , near and far field , full width at half maximum , fresnel equations , ray tracing (physics) , materials science , fresnel zone , beam (structure) , fresnel lens , physics , diffraction , refractive index
This paper presents a novel method in near-field beam shaping based on the precise optical modeling of a gallium nitride light-emitting diode (GaN LED). A Monte Carlo ray tracing simulation has been utilized to calculate the spatial photon distribution near the LED's top. By analyzing the ray data in near-field, the miniaturized lens profile is created and machined with aspherical surfaces and total internal reflection (TIR) Fresnel facets. The prototype lens reduce the viewing angle of the LED from 150 degrees to 17.5 degrees at full width half maximum (FWHM) while increasing the peak luminous intensity 10 times. The array of proposed lens with CSP LEDs exhibits feasibility of ultra thin uniform illumination in near-field.