BRIGHTNESS CONTROL DEVICE AND METHOD

A brightness control device includes a back light panel, a controller, and an image signal processing chip. The back light panel includes a blue light LED module and a green light LED module. The controller includes a converting module and a sub-control module. The image signal processing chip includes a main control module and a storing module. The storing module stores first corresponding data and second corresponding data. The main control module sends two initial pulse signals corresponding to a brightness of the two light LED modules to the converting module. The converting module converts the two initial pulse signals into direct current signals and sends the direct current signals to the sub-control module. The sub-control module sends a first drive current signal and a second drive current signal to the blue light LED module and the green light LED module.