Backlight LED pulse drive method and luminous efficiency

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.