Development Of Color & Brightness Correction System For Panel Displays

Display panels have been widely used in our daily life and consumers now demand displays with better performance. However, there are some differences in the brightness and color gamut between displays produced by different companies or different technologies because of the limits of industrial productions and research. Even display panels from the same company may have some slight gap. However, there are great requirements for high performance in video splicing unit, professional displays and some other applications. Therefore, color and brightness correction for display panels is extraordinarily necessary.The development of color & brightness correction system of display panels is presented in this paper. The color management IP core was adjusted based on the FPGA board with the function to adjust digital video signal, which is independently developed by the Display Center of Southeast University. The color gamut and brightness of displays were precisely modified and the same performance for the displays in both aspects is finally achieved. Besides, the performance of displays can be corrected to meet the needs of customers. The method has been optimized to calculate the parameters of color management IP core. The largest color gamut and the closest-to-standard color gamut strategies were designed. Moreover, the brightness in different grayscales was adjusted to make it more consistent with the Gamma characteristic. At the same time, MicroBlaze was applied in FPGA to configure the color management IP core and FatFs file system was used to access and store parameters from PC programs. Finally, PC interface was designed to interact with users and exhibit the result of correction.The test data show that the system has the ability to adjust individual displays and resolve the inconsistencies of different displays in color gamut and brightness. The error between actual brightness and target brightness is less than ±2 cd/m~2 and the error of three primary colors of Gamut Range in x-y coordinate is less than ±0.02. Besides, there is an obvious reduction of the color difference ?E. The data prove that the color gamut and brightness of display panels can be corrected effectively to meet the needs of video splicing unit, professional displays and some other applications.