A Research Of Drive Technology For 5-inch OLED

OLED (Organic Light Emitting Display) has been worldwide subject of intensive studies on new generation display technology nowadays. And AM(Active Matrix) drive technology is an important key that leads OLED development on large dimension and high resolution. This paper aims at the research on drive technology of LTPS (Low Temperature Poly-Silicon) TFT (Thin Film Transistor) AM-OLEDs. For the natural characters of Poly-Silicon material, the threshold and carrier mobility of individual TFTs are not the same. This paper utilizes sub-field digital gray scale technology that based on time ratio gray scale. All the TFTs are operating at either cut-off region or saturation region. This solution bypasses the non-uniformity of Poly-Silicon TFTs, and increases the bright uniformity and gray scale accuracy of LTPS AM-OLED. Meanwhile, this paper makes use of DSP composite ping-pang structure and dual-channel RAMs output constructions, resolves some problems going with the rising of dimension and resolution of display device, such as exponential rising of driving frequency, and charging time limit of pixel capacities, respectively. On the platform built by Altera FPGA and Quartus II 4.0 software, display device controlling program is compiled by Verilog HDL (Verilog Hardware Description Language), with DVI (Digital Video Interface) induced. Then real time hardware circuit is constructed after designing and producing the PCBs. Furthermore this paper gives detail analysis and corresponding solutions about the problems on FPGA hardware design, like source limit. Finally, nice images and real time dynamic video are achieved on 5-inch colorful AM-OLEDs with 16 gray scales and 320×240×3 resolution.