动态背光控制对液晶响应时间的影响OA

Leakage of light is a common phenomenon when a Liquid Crystal Display(LCD)screen displays a black pattern,mainly caused by the combination of the screen structure and the characteristics of the backlight system.A common and simple yet effective way to address this issue is to reduce the overall screen brightness,which can significantly decrease the visibility of the leakage.This paper systematically studies the variation rule of the liquid crystal response time after activating the dynamic backlight control,and measures the liquid crystal response time data under black and white pattern with different PWM(Pulse Width Modulation)duties output by the Timing Controller(TCON).This is achieved through the Dynamic Backlight Control(DBC)function in the TCON,where the PWM duty output by the TCON is 40%of the input PWM when displaying a black pattern,and 100%of the input PWM when displaying a white pattern to the Light Emitting Diode(LED)driver.This method can improve the leakage of the black pattern,but in Direct Current(DC)dimming applications,combined with the mechanism of the LED driver identifying the PWM duty and then outputting the LED current,it will lead to an increase in the liquid crystal response time.The test result of the optical instrument is 51.9 ms,which seriously exceeds the design specification of Max 25 ms.To address this issue,this paper proposes an optimized scheme:the PWM duty for the white pattern output is adjusted to 99.6%,while the maximum brightness of the LCD screen remains unchanged.The measured liquid crystal response time can be shortened to 24.7 ms,which not only solves the problem of black pattern leakage but also meets the liquid crystal response time specification.