Mun-pyo Hong

13.3 Co‐Optimization of Color AMLCD Subpixel Architecture and Rendering Algorithms

Color subpixel rendering is enhanced by co-optimizing the color subpixel architecture and algorithms with respect to human vision, resulting in the PenTile Matrix™ subpixel architecture to double the addressability and the MTF limit in both horizontal and vertical axes while reducing driver count. Results of prototype AMLCD panels demonstrate improved text and full color image quality.

9.2: Implementation of RGBW Color System in TFT‐LCDs

Last year, we introduced a TFT-LCD with RGBW color system. The primary advantage of the RGBW system is that its optical efficiency is at least 50% higher than the RGB system. However, it is not a simple task to incorporate the new color system into the existing infrastructure of the RGB system: the driving circuitry, fabrication of color filter, and color conversion. In this report, the practical hurdles are discussed and the solutions are presented.

3.3: Large Area Full Color Transmissive a‐Si TFT‐LCD Using Low Temperature Processes on Plastic Substrate

A 5.0-inch transmissive type plastic TFT-LCD was developed at the resolution of 400 × 3 × 300 lines (100ppi). All of the processes of TFT, color filter and LC were carried out below 150 °C on PES plastic films. The process conditions of TFT, color filter and LC were optimized for large area TFT-LCD on plastic substrate. The overall module including a backlight unit is of course bendable and of thickness of about 1.2 mm and 22.0g of weight, which are a third of normal glass-based display, respectively.

31.1: Development of Six Primary-Color LCD

We developed the multiple primary color LCDs where the pixels were composed of red(R), green(G), blue(B), cyan(C), magenta(M) and yellow(Y) subpixels. The color gamut was extended 99% of NTSC standard, while the brightness was also increased by 15%, compared to the conventional RGB three primary color LCDs. To get a natural color image we designed the color coordinates and luminance levels of each six subpixles, and developed color algorithm to convert the RGB signal to RGBCMY signal.

28.3: A High‐Resolution Full Color TFT‐LCD on Transparent Plastic

We developed a 93 DPI full color TFT-LCD (2.2 inch) on transparent plastic (PES) using hydrogenated amorphous silicon thin film transistor (a-Si:H TFT). The low temperature process (<150) and the island formation of inorganic layers give a stress-free AMLCD on PES.

P‐164: Single Cell Gap Transflective Mode for Vertically Aligned Negative Nematic Liquid Crystals

Single cell gap transflective liquid crystal display mode with vertically aligned negative liquid crystal was developed. Reflectance curve as a function of voltage matched exactly with transmittance curve. Threshold voltage in reflectance curve was around 2.0V, as in transmittance curve, and the voltage for maximum reflectance was around 4.5V∼5.0V, which gave also the maximum transmittance. Reflective region was divided into two parts. First reflective part was driven by the voltage supplied by switching transistor directly, while the second reflective part was driven by the voltage lower than that of first part using the voltage-dividing capacitor connected to switching transistor in series. Normal 8 mask-count process was applied to fabrication of real panels. No special optical film or extra driving circuit was required.

3.4: Invited Paper: Developments of Transmissive a‐Si TFT‐LCD using Low Temperature Processes on Plastic Substrate

In this paper, we describe the formatting guidelines for the SID: International Symposium Digest of Technical Papers. By downloading this template from the website, you will have the formats for your article, so that it can be electronically submitted.

New approaches to process simplification for large-area high-resolution TFT-LCDs

Novel process architectures are proposed for fabricating large-area high-resolution TFT-LCDs with a minimal number of process steps. A low contact resistance between Al bus lines and the transparent conductive oxide layer, necessary for large-area panels, is obtained by inducing a self-formed inter-metallic compound layer at the interface without using any additional buffer or capping layers. For enhanced brightness and resolution, a new TFT array structure integrated on a color-filter substrate, referred to as an Array on Color Filter (AOC) structure, has been developed. Good-quality TFTs were successfully constructed on the newly developed color filter for AOC within a sufficiently wide process margin. By adopting these novel technologies, a 15.0-in. XGA prototype panel was fabricated and shows good display performance. Thus, these novel technologies have improved cost efficiency and productivity for TFT-LCD manufacturing, and can be applied to the development of TFT-LCDs of extended display area and enhanced resolution, benefiting from the low resistance bus lines, the high aperture ratio, and reduction in total process steps.

34-3: Transmissive 7″ VGA a-Si TFT Plastic LCD Using Low Temperature Process and Holding Spacer

A 7.0-inch transmissive type plastic TFT-LCD was developed at the resolution of 640 × 3 × 480 lines (114ppi). All of the processes of TFT, color filter and LC were carried out below 130 °C on PES plastic films. The process conditions of TFT, color filter and LC were optimized for large area TFT-LCD on plastic substrate. The backplane and the color filter was strongly adhered while the panel was bending by using holding spacers.

44.1: Invited Paper: New Approaches to Process Simplification for Large Area and High Resolution TFT‐LCD

Novel process architectures are proposed for fabricating large area, high resolution TFT-LCDs with a minimal number of process steps. A low contact resistance between Al bus lines and transparent conductive oxide layer, necessary for large-area panels, is obtained by inducing a self-formed, inter-metallic compound layer at the interface without using any additional buffer or capping layers. For enhanced brightness and resolution, a new TFT array structure integrated on a color filter substrate, named Array on Color Filter (AOC) structure, has been developed. Good quality TFTs are successfully constructed on the newly developed color filter for AOC within a sufficiently wide process margin. By adopting these novel technologies, a 17.0″ SXGA prototype panel is fabricated and shows good display performance.