Technical / Research - Page 129

Cambridge Display Technology (CDT) announces the achievement of another important milestone with the development of blue polymer OLED emitting devices with 100,000 hours lifetime* from an initial luminance of 100 cd/m².

This latest announcement is one of a series which CDT has made to enable the industry to chart its progress on this key parameter. Figures of 30,000, 70,000 and 80,000 hours (all from 100 cd/m²) were published in May, October and December 2004.

The 51 year-old Jang jin and 37 year-old Park Gyu-chang Professorial research team of the department of Information Display, Kyunghee University, yesterday announced that it has succeeded in developing 'Phosphorescent organic light-emitting diode (OLED)' that measures 2cm in width, 1.5cm in height and 3mm in thickness. All the OLED materials developed so far consist of fluorescent materials that emit light only when electric flows and stop emitting promptly if electricity is turned off. However, the research team applied a fluorescent material that emits light for a long time even after electricity is turned off for the first time. "The new phosphorescent OLED is brighter than OLEDs made from fluorescent materials, resulting in sharply reduced power consumption and extended life-span," Professor Park said. " In addition, it can have the effect of two conventional display outputs by allowing screens on both sides (front and back)," The technology was developed as a result of a three-year R&D grant sponsored by UDC, who retains the source technology of phosphorescent materials, and is scheduled to be unveiled at the Information Display Association International Symposium planned to be held in the U.S on 24 this year.

Samsung Electronics, the leader in TFT-LCD technology, today announced that it has successfully developed the world's first single-sheet, 40-inch active matrix (AM) OLED for emissive flat panel TV applications. The high-definition-compatible OLED prototype has a wide screen pixel format of 1280x800 (WXGA) driven by an amorphous silicon (a-Si) AM backplane to permit faster video response times with low power consumption.

Samsung's 40-inch OLED panel will be demonstrated for the first time at the world's largest display industry event, Society for Information Display (SID) 2005 International Symposium, Seminar and Exhibition in Boston, May 24- 27.

Philips and German firm Novaled have announced white OLEDs operating at a brightness of 1000cd/m² with a record-breaking efficiency of 25lm/W.

work between Philips’ Lighting and Research divisions, and Dresden-based Novaled, combined Philips’ materials selection, optical outcoupling technology, and layer schemes for building up OLED devices, with proprietary doping technology from Novaled.

This is an encouraging result that clearly demonstrates the potential of OLED technology for lighting applications, said Klaas Vegter, chief technology officer of the Lamps business group at Philips Lighting.
The results of the research will be used in future developments, ongoing projects, and the recently started European project OLLA (Organic LEDs for Lighting Applications), in which both companies are involved.

Sumitomo Chemical and The Dow Chemical Company announced today that Sumitomo Chemical has purchased the LUMATION Light-Emitting Polymers (LEPs) business from Dow. Financial terms were not disclosed. Sumitomo Chemical's acquisition of LUMATION LEPs will strengthen the company's LEP technology-based business, in line with its strategy.

Sumitomo Chemical has developed fluorescent and phosphorescent LEPs based on the company's long-established display material and conducting polymer technology. Sumitomo Chemical's blue-color material achieved 10,000 hours of brightness half-life. The material is ideal for a printing method, a much simpler and more cost effective production process for large-sized displays than the vacuum deposition method used for small-molecular OLEDs. The company is also developing highly efficient new materials such as dendrimers in cooperation with Cambridge Display Technology.

Universal Display Corporation today announced it has been awarded a two-year, $1.7 million Small Business Innovation Research (SBIR) Phase III contract by the U.S. Department of Defense to continue its development of flexible OLED display technology for a next-generation military communications device.

In this Phase III contract, Universal Display is to develop and deliver functional prototypes of a Portable Flexible Communication Display Device. This futuristic communications device will be form-fitted to a soldier's wrist and communicate wirelessly to a nearby computer, thereby enabling soldiers to see crucial video and graphics information in real time.

The device will use a full-color, AMOLED display built on metal foil. The use of metal foil substrates can lead to a rollable, retractable and rugged display with a small and lightweight form factor for use in portable communication devices. Universal Display's FOLED® flexible OLED technology, combined with its TOLED® top-emission OLED technology, enables the use of flexible metal foil as a substrate material. With a 4-inch diagonal screen, the 320 x 240 pixel (QVGA format) AMOLED display will also use Universal Display's proprietary high-efficiency PHOLED™ phosphorescent OLED technology and materials.

AU Optronics Corporation has introduced Double Sided Active Matrix OLED. This technology allows showing simultaneously, two separate images, moving or still, with 143 ppi (pixel per inch) resolution and 200 nits (cd/m2) brightness, on one panel. With specifications of less than 1 ms response time, contrast ratio of more than 1000:1, and viewing angle of >170 degrees, it is suitable for small sized consumer electronics solution.

Toppoly has introduced the 2.5 AMOLED and the 1.8 System-On-Panel. The 2.5 full color AMOLED module is based on an LTPS backplane and features integrated driving circuitry, producing a light, thin and compact display module. The product integrates scan and data driver ICs onto the panel. The module supports a resolution of 640x240 in 262K colors with a 130-pixel pitch and is suitable for DSC, DVC and portable multimedia devices.

The 1.8 System-On-Panel LTPS TFT-LCD supports 65K/262K colors at a resolution of 128xRGBx160, and integrates the scanning circuitry (both horizontally and vertically), Level Shifter, and DC-DC Converter onto the panel.

Solomon Systech Limited unveiled, SSD1335 and SSD1338, the OLED driver ICs with integrated controller. They have a built-in DC-DC voltage converter, a 16-steps master current control, a 256-steps contrast control for three-color components and embedded SRAM. SSD1335 supports up to 132 RGB x 88 x 18 bits resolution OLED panel and SSD1338 supports up to 132 RGB x 132 x 18 bits resolution OLED panel, which provides 262K color to display.

SSD1335 and SSD1338 also feature 18-bits controller for color passive common cathode type OLED/PLED panel. The ICs also feature contrast setting, column and row re-mapping, programmable multiplex ratio and vertical scrolling. It provides functions such as, line drawing, rectangle drawing, copy-&-paste image, dimming window and clearing window, etc.

CDT has taken an important step in the development of PLED technology with the commencement of an intensive two-year program to develop 'top emission' display devices.

The aim of the program is to develop a process to enable manufacture of a top-emitting P-OLED device structure utilising a transparent cathode, which will have enhanced lifetime and efficiency compared with bottom-emitting RGB devices. The program will, additionally, develop 'know-how' associated with the manufacture of transparent cathode devices.