Technical Insight
DuPont and Toshiba boost OLED displays (Opto News)
DuPont Displays of Wilmington, Delaware is teaming up with RiTEK Display of Hsinchu, Taiwan to set up a high-volume production facility for the manufacture of polymer-based OLED screens. Employing proprietary technology supplied by DuPont and its wholly-owned subsidiary UNIAX, Dupont will deposit OLEDs onto RiTEK s glass panel substrates up to 370 470 mm. Slated for operation in late 2002, the new facility will be built at RiTEK s current plant, which features an existing monochrome OLED line and is currently undergoing an expansion to include a full-color OLED line. According to RiTEK s CEO, D Wang, the new line will represent the first fully-automatic OLED mass production line in the world. When operational, the plant will have a capacity for 35 000 large-area OLED panels per month. While initial production will be focused on monochrome displays on glass substrates, DuPont says it is developing full-color, active matrix displays which are based on a flexible plastic substrate. Toshiba develops color OLED display Japanese electronics giant Toshiba has developed what it says is the world s first prototype of a full-color polymer-based OLED display. Toshiba s panel is 2.85 inches across the diagonal and contains 25 344 pixels, in addition to supporting 260 000 colors. The company produced the display by applying a light-emitting polymer film onto a low temperature poly-silicon thin-film transistor array using a combination of its proprietary ink-jet printing and solvent-material technologies. Toshiba originally developed the low temperature poly-silicon process to replace amorphous silicon used in its LCD displays, and says this approach is key to allowing the high carrier mobility required in large active matrix displays for OLEDs. Such matrixes contain a transistor to drive each pixel, and offer superior color, power consumption and picture quality compared to LCDs. Toshiba s printing approach does not require vacuum deposition and allows easier manufacture of larger area displays, says the company. The display emits light in a wide viewing angle and dispenses with the need for backlighting which is required for LCD screens meaning the screens have the potential to be thinner and lighter. Commercial production is expected in April 2002, and initial markets will include cellular phones and PDAs, followed later by large displays for PCs.
