PWM dimming with complementary color Graphic Oled Display Module

Orange and blue light preparatory work before the fill color
1) the drive voltage should be able to guarantee the voltage required by the LED lamp, the constant current output; (2) the output current of the drive circuit should have the consistency of the conduction time, can be done so that the brightness of the linear regulator; (3) in the daytime mode White should be gradually increased, and the complementary color of blue light and orange light should gradually increase the proportion of white lights change.OLED Module

Closed-loop color control
Constant and and do fitting the backlight temperature curve consistent case, dimming in the entire luminance range can be a standard white light source, the temperature of the backlight in accordance with the fitting curve obtained. But to ensure the backlight LED lamp constant temperature is impossible, attenuation of white light, orange light, and blue light are not the same, with the temperature change of the LED lamp, the color temperature will be drift phenomenon.
Record the color sensor 200 dimming cycle, 100ms, red, green, and blue color component output pulse number, these data as the luminance values ​​of the three color components.
Changes in temperature, according to the brightness of the color sensor measuring the red, green and blue color data to fine-tune the orange light and blue light PWM waveform is high time, the red, green and blue brightness ratio constant color temperature is maintained unchanged.COG LCD Module

SS-230 flat panel display system analytical instruments, changes from low brightness to high brightness measured 40 points, PWM pulse high time to adjust the lights, get the standard white light source. Then the linear fitting method to obtain the ratio between the high level duration of the PWM waveform of the three kinds of light under different circumstances, the brightness can be guaranteed within the scope of the entire luminance of the backlight source is a standard white light dimmer according to the relationship. According to the color sensor output red, green, and blue color channel data, the PWM high time to fine-tune the orange light and blue light, to maintain the red, green, and blue color channel data proportional to the same color temperature constant. The approach adopted within the screen white color temperature (500 ± 100) K, the color coordinates u ', v' 0 198 ± 0 01 less than 0 468 ± 0 01 less than the standard white light.