Patent ID: 8711084

Claim:
A brightness control device in an OLED display device comprising: a computer system having either a PWM controller for converting and forwarding external brightness control information into a PWM (Pulse Width Modulation) signal and forwarding the PWM signal or a master for forwarding brightness control data by using a data communication protocol; a selector for selecting either the PWM signal from the PWM controller or the brightness control data from the master; a normalizer for normalizing the PWM signal or the brightness control data from the selector into an external brightness adjusting gain; a peak brightness value detector for analyzing a video data from the computer system to detect a peak brightness value; a multiplier for multiplying the peak brightness value by the external brightness adjusting gain to produce a final peak brightness value; a maximum gamma voltage adjuster for adjusting R/G/B maximum gamma voltage values according to the final peak brightness value; and a reference gamma voltage generator for generating R/G/B reference gamma voltage sets by using the R/G/B maximum gamma voltage values from the maximum gamma voltage adjuster, wherein: the computer system is used for both the OLED display device and a liquid crystal display device, when the computer system drives the OLED display device, the PWM controller or the master controls the R/G/B maximum gamma voltage values for the reference gamma voltage generator, and when the computer system drives a liquid crystal display device, the PWM controller or the master controls a backlight unit in the liquid crystal display device.