Flexible displays finally a reality? Enter Bio-nanofibers. Handhelds / Pioneer Posted by zmcnulty on Jan 25, 2005 - 10:12 PM |
|
In what looks to be one of the most technical articles I've translated in a long time, Kyoto University, Pioneer, and Rohm all got together to announce some new technologies they've developed intended for use in flexible displays. Kyoto University, Pioneer Corporation, and Rohm Corporation announced on the 25th that they have developed new technologies intended for use in flexible displays. There are two new technologies: a "bio-luminescent transistor," an organic transistor with EL luminsense, and a "low heat expanding transparent substrate," through reinforcement of the original bio nanofibers. An application for these results is that it is now possible to create display devices that are light, flexible, hard to break, and can display on curved surfaces. Some sample tangible applications include flexible displays for mobile devices, electronic paper/newspapers, and electronic posters. Both of the technologies were announced as the results of the "Comprehensive Production United Alliance," created by Kyoto University, Nippon Telephone and Telegraph (NTT), Pionner, Hitachi Manufacturing, Mitsubishi Kagaku, and Rohm. At the core of the alliance was Kyoto University, with cooperation in the development of the bio-luminescent transistor coming from Pioneer and Rohm, and cooperation in the development of the low heat expanding transparent substrate from Pioneer and Mitsubishi Kagaku. The bio-luminescent transistor is a composite device that equips and organic transistor with EL luminescent capabilities. With the usage of this element, when combined with an active-matrix type display device, allows for the composition of a device on par with a powered transistor and light element -- allowing for a drastic reduction of parts versus current organic EL displays. For this bio-luminescent transistor, source, drain, and gate electrodes are arranged inside of a new organic compound. Just like on current organic transistors, the gate voltage can vary the drain current, thus allowing the gate voltage to govern the volume of EL luminescense. The external quantam efficiency of the luminescense is about 0.8%, making it "easily bright enough for usage as a mobile phone display." The low heat expanding transparent substrate is a flexible transparent substrate, invented based on the concept that transparent nanofibers organic in origin can reinforce transparent polymer materials. The Alliance has dubbed this material "Bio-nano fiber composite." The reinforcement material consists of transparent fibers with a a diameter of under 100nm, so while retaining flexibility, offers both a parallel light transmission efficiency of over 85% in transparency and low-line thermal expansion coefficient similar to that of glass. Up until now, conventional polymer materials were laid as metal wiring on top of a substrate; the transparent conduction membranes and gas-barrier membranes were burdened by temperature during the assembly processes and packaging processes. The differences in thermal expansion coefficients of the substrate materials would lead to severed lines, making damage possible, and in turn remained as the largest barrier to the realization of flexible display devices. On bio-nanofiber composite, however, because the fiber diameter is "nano-size," the transparency is not controlled by differences in bending coefficient and resin. Also, because of the fiber shape's filler, the volumetric mean between the thermal expansion coefficient, filler, and matrix resin, has been greatly reduced.   Inspired by: http://www.watch.impress.co.jp/av/docs/20050125/oled.htm [1] Press Release (Pioneer): http://www.pioneer.co.jp/press/release473-j.html [2] Press Release (Rohm): http://www.rohm.co.jp/news/kekka2-j.html [3] |
|
This article is from TechJapan http://www.techjapan.com/ The URL for this story is: http://www.techjapan.com/modules.php?op=modload&name=News&file=article&sid=839 Links in this article [1] http://www.watch.impress.co.jp/av/docs/20050125/oled.htm [2] http://www.pioneer.co.jp/press/release473-j.html [3] http://www.rohm.co.jp/news/kekka2-j.html |