Research Of Dynamic LED Backlight Control Technology

In the field of LCD, LED backlight with its wide color gamut and high brightness is gradually replacing the traditional CCFL backlight. Dynamic LED backlight is a new technology generated from direct type LED backlight. Dynamic LED backlight is based on image content to adjust the LED brightness dynamically for achieving lower power consumption and improving the contrast. The study of dynamic LED backlight is only in the infancy stage in the international and domestic. The dynamic processing algorithm, LED backlight modules and LED drivers still need to be improved.What we have done includes the following aspects. First of all, we analyzed the basic working principle of current LED backlight based on its introduction, and pointed out its disadvantages to explain the significance and direction of our research subject. Secondly, we analyzed the impact of LED light source, light guide plate, diffusion film and prism film on LED backlight system based on the structure of LED backlight module. Then we designd LED optical box as a unit to suit for dynamic LED backlight system. We also used optical simulation software to test the design and to optimize backlight system parameters. Thirdly, in the background of LED optical box, we proposed the algorithm of Dynamic LED backlight and selected different types of representational images to simulate the algorithm. The experiment also tested the dynamic control algorithm for reducing energy consumption and improving image display quality and performance, while optimizing the value of gamma. Lastly, construct a universal highly LED backlight circuit system and its main circuit consists of a host FPGA chip, dual-channel LDVS receiver and transmitter, SDRAM and so on. We used software for the dynamic LED backlight circuit system to get the internal function design of FPGA and SDRAM memory logic design. The system can be achieved to access regional images and to give the way of how to complete the pixel data reading and writing in the alternate operation by using SRDAM.