Efficiency Evaluation of Phosphor-white High-power Light-emitting Diodes

Abstract

High-power light-emitting diode (LED) efficiencies are strongly dependent on device type and operating conditions. Electrical and optical power measurements are performed on five commercially available phosphor-white LED types for a number of independently enforced forward currents and junction temperatures. The experimental results allow for a comparative evaluation of dominant loss mechanisms and their current and temperature dependences.