9.2: A 5.0‐in WVGA AMOLED Display for PDAs

Abstract

Samsung SDI has developed a full color 5.0″ WVGA AMOLED display using top emission structure with a super fine pitch of 0.1365 mm 186 ppi, the world's highest density OLED display ever reported to date. Scan driver circuits and demux circuits were integrated within the display panel, using low temperature poly‐Si TFT CMOS technologies, and data driver circuits were mounted using COG IC. Peak luminescence was greater than 300 cd/ with power consumption of 500 mW with 30% of the pixels on.

P-8: A Novel Feedback-Type AMOLEDs Driving Method for Large-Size Panel Applications

“…Note in Figure 3 (b) that the gate voltages of the driving TFTs are equal at the initial programming time, but are adjusted to generate a target current with their mobility, respectively. To compare the error percentage of the current of OLEDs during emission time from pixel to pixel, simulation results for four kinds of prior pixels have been selected [4][5][6][7]. The conditions of the OLEDs and panel parameters are summarized in Table 1 and Table 2 respectively.…”

“…We can find roughly four kinds of prior AMOLED pixels, based on voltage programmed current source and mirror, current programmed current source and mirror [3][4][5][6][7]. Mostly, voltage programming methods still have the OLEDs-current variation problem from the mobility variation of poly-Si TFTs, and current programming methods sees the problem of charging the large capacitive load of a data line with a low level current [11][12].…”

“…In this paper, we propose a new feedback-type OLEDs driving method for 30-inch HDTVs on poly-Si backplane to solve those problems and shows the improved driving current uniformity compared to the prior pixels under the threshold and mobility variations [4][5][6][7].…”

49.4: Two TFT Pixel Circuit with Non-Uniformity Suppress-Function for Voltage Programming Active Matrix OLED Displays

“…However, these circuits require more TFTs in each pixel. The well known Vth variation-compensation circuit requires four TFTs and two capacitors [1], while most others require four [2] to six TFTs [3] in each pixel. Therefore, a complicated pixel circuit makes the OLED area smaller because more TFTs occupy a larger pixel circuit area.…”

“…However, there is another issue with the power consumption. Because the recent top-emission OLED structure requires semitransparent cathode metal [2] [3], part of the emitting light is absorbed in the cathode metal. A new pixel circuit that must realize both inter-pixel non-uniformity suppression and sufficient OLED area provision without wasted emitting light absorption is strongly required.…”