Optical analysis of a 3W light-emitting diode (LED) MR16 lamp

Abstract

Optical analysis is critical to the evaluation of an LED MR16 lamp, especially when the lamp is still in its early stage of development and applications and when optimization is needed for making use of unique characteristics of LEDs. In this study, optical research of a 3W LED MR16 lamp was conducted. The experimental results demonstrated that the LED MR16 lamp’s angle of full width at half intensity was about 30 degrees and the luminous efficiency reached as high as 53.5lm/W, which was accepted for the illumination requirements. Numerical simulation was also conducted. The feasibility of the numerical model was proven by comparison of the simulations with the experimental data. Through the simulation and the corresponding analysis, it was found that tested 3W LED MR16 had high optical efficiency (90.2%) into all angles, but had poor beam pattern design, especially for the low uniformity of the beam pattern and low optical efficiency of light into main beam (less than 60%). To improve the illumination performance, a modified non-imaging optical design method was suggested to enhance the uniformity of beam pattern, to enhance the optical efficiency into main beam and to reduce the optical system volume. A novel high power LED MR16 with high beam pattern uniformity and high optical efficiency was designed as an example.