Hiroshi Takahara

9.4: A Novel Current Programmed Pixel for Active Matrix OLED Displays

A novel current programmed pixel and driving method for AMOLED displays have been developed. The newly developed pixel, which is called ‘Current-Copy Pixel’, shows the highest potential to suppress luminance non-uniformity. This pixel design was implemented into our developed full color AMOLED display, and its high luminance uniformity was confirmed.

11.4: OCB‐LCDs with New Driving Method Having Fast Response of 2.3‐ms MPRT and High Contrast Ratio of 1000:1

We have developed high performance OCB-III TFT-LCDs using LED blinking Backlight. The MPRT of 2.3 ms, which is the fastest in the world, and high contrast of 1000:1 are achieved with 12.1 inch SVGA OCB-III panel. Even at low temperature of −20C. the MPRT of OCB-III is 13.2 ms which is 1/4 of conventional LCDs. The OCB-III can be superior to the CRT in quality of motion picture.

60.5L: Late‐News Paper: An Improved Current Driving Method for 256‐Level Full Color Active Matrix OLED Displays

Because full-color OLED displays are RGB and the current-luminance characteristics of OLED devices differ from one another, their white balance adjustment is difficult. Another problem is that OLED displays draw a large current when images are displayed at high luminance, which causes heating and deterioration. We propose an improved current driving method to solve both problems, and we developed a current-output source driver IC which achieves 256 levels each for RGB, and a full-color active-matrix OLED display with a 3.46-inch diagonal and current-driven 320 RGB × 240 pixels (QVGA).

36.5L: Late‐News Paper: Development of Source Driver LSI for AMOLED Displays Using Current Driving Method

We have developed a source driver LSI for active matrix OLED displays using the current driving method. The current driving method is better able to overcome non-uniformity of pixel transistor characteristics, such as threshold voltage and mobility, than either voltage or PWM driving. We propose two current driving topologies: a new type of reference source distribution and a new type of gamma correction circuits.