Backlight LED pulse drive method and luminous efficiency

摘要

The affect coefficient between the luminous efficiency of backlight LED and the pulse driver parameters is experimentally studied with a novel test method. The experiment results show that the LED luminous efficiency was substantially decreased when the LED was driven by a high peak and low duty ratio pulse current. Given 200–2000Hz and 10–90% duty ratio pulse current, the LED got relatively higher luminous efficiency, while the efficiency could decrease by 2–5% as the modulation frequency rose to 20000Hz. Given the rated peak pulse current with low duty ratio, LED luminous efficiency could increase by 10–30% given the smaller ripple coefficient pulse current, the LED luminous efficiency increased. The work in this paper could contribute to the LED's drive design in the field of LCD backlight, electronic display and studio lighting.