Studies On The Driving And Testing Of Flexible AMOLED Based On ARM+FPGA

Organic light emitting diode display(OLED) is the new promising display technology, called “dream display”. Light emissive displays are emerging and promising display that provides much wider view angle 、more colorful 、higher contrast and faster then TFT-LCD, it’s mass-production technology is being rapidly developed.The luminescence of the OLED device is provided by a thin film transistor(TFT) array which provide a current for the OLED. Thin film transistor is the key element to control the OLED luminescence. At present, the TFT technology includes amorphous silicon, polycrystalline silicon, metal oxide TFT and so on. Metal oxide TFT has a higher ratio of performance to price ratio in terms of migration and cost. At present, the domestic OLED uses metal oxide TFT, so we need to design the corresponding drive technology.The flexible AM OLED is being developed now,Flexible AMOLED display has become a hot spot. It has many advantages: lightweight, folding, flexible, mechanical shock, with its large-scale application, it will bring huge changes to people’s live.This paper first describes working principle of the AMOLED(active matrix organic light emitting diode), and then according to the demand of flexible AMOLED display,we design a drive system which is more convenient and easy to display. The system uses the hardware frame of FPGA and ARM, which ARM system is as image source, FPGA as the timing control module, to produce the signal that meet the demand of the driver chip which complies with the flexible AMOLED display screen, to realize the drive. This system well implement image play on a 5 inches oxide-based AMOLED display with 200(RGB)×600 resolution, the display effect is good.The core technology of this paper includes:1) the selection of the source and gate driver chip, the driving voltage of the oxidation of TFT is higher and the lack of a dedicated driver chip, this paper uses TFT-LCD driver chip as AMOLED’s gate and source driver; 2)Image source generation. First of all, through the modification of ARM processor built-in LCD controller driver and the plantation of Linux core, then develop the self-triggered program based on Qtopia, so we finish the development of embedded software platform, and achieve auto start display image since the system boot; 3) timing control module design, using FPGA to design the data buffer, to generate the appropriate timing to meet the requirements of flexible AMOLED display.Finally, since the Flexible AMOLED display is in the preliminary stage of development, and at this stage there is no international standard for its testing, this paper simple performance test parameters indicators based on existing AMOLED flexible displays, and evaluate it, provide a reference for the future of flexible AMOLED display of process improvement and development.