38.2: 302-ppi High-Resolution AMOLED using Laser-Induced Thermal Imaging

Abstract

Samsung SDI has developed 2.6-inch full color VGA Active Matrix Organic Light-Emitting Diode (AMOLED) display with the world's highest resolution of 302ppi using Laser Induced Thermal Imaging (LITI) method with the top emission structure. A voltage compensating pixel circuit with 2µm design-rule in lowtemperature poly-Si (LTPS) thin film transistors (TFTs) was introduced to compensate the variation of the threshold voltage (Vth) in order to improve the image quality. Moreover, an aperture ratio of ~40% was obtained for each pixel even though the sub-pixel pitch was 28um. The luminance for the white color was 200cd/㎡ and color gamut was 74% compared to national television standard committee (NTSC) standards. These results show the possibility of high-resolution AMOLED display incorporating the LTPS technology and LITI method for digital mobile era applications in the near future.

53.2: Invited Paper: Large‐Area Color‐Patterning Technology for AMOLED

“…The BCL structure in combination with LITI process could reduce the total number of OLED process to fabricate full-color AMOLED since only two steps of LITI process is required for color patterning. Moreover, in top-emission AMOLED, the microcavity structure is employed in order to enhance the color purity and emission efficiency as different total layer thickness should be introduced for each red, green and blue pixels, respectively [9,10]. In this context, multi-stacked OLED layers with different total thickeness can be transferred at a time without intermixing between each layer because LITI is a mass transfer process.…”

Image-Quality-Based Power Control Technique for Organic Light Emitting Diode Displays

“…In recent years, OLED displays have widely replaced liquid crystal displays (LCDs), owing to several factors [1], [2]. First, unlike LCDs, OLED displays do not require a backlight; hence, they are thinner and lighter than LCDs.…”