The impacts of high frequency pulse driving on the performance of LED light

Abstract

Due to the high lighting efficiency and long lifecycle, the light-emitting diode (LED) plays a major role in the green earth activities; energy saving and carbon offset. Since the LED lights have the better energy efficiency, they have gradually become the major source of LCD backlight. The luminance of LED light source must be adjusted suitably when used for the backlight source or lighting, therefore, the pulse wave modulation (PWM) is a commonly used technique for the LED light modulation. However, when the LED is applied to the field sequential color LCD for a long time, the trigger pulse will readily affect the LED light performance. This paper presents the impacts of PWM driving on the performances of LED; color temperature, luminance efficiency and lifecycle. © 2011 Published by Elsevier B.V.