Communications of the ACM
Brighter Idea For Bendable Displays
A freely deformed stretchable array of complementary metal-oxide semiconductor inverters.
Credit: Professor John A. Rogers and University of Illinois at Urbana-Champaign
University of Illinois at Urbana-Champaign professor John Rogers has led the development of a new technique for manufacturing tiny inorganic light-emitting diodes (LEDs) that enables them to be attached to materials such as glass or rubber. The new manufacturing method "enables new kinds of 'form factors' that would allow you to put lighting sources on curved surfaces or in corners, places where you can't put light sources nowadays," Rogers says.
The breakthrough means that technology currently used in large video billboards can now be used in flexible and transparent displays to create a variety of products, such as brake lights that fit the curves of a car or medical diagnostic equipment that can be wrapped around a patient like a blanket.
The majority of consumer electronics use inorganic LEDs, which are 400 times brighter per square centimeter than organic LEDs. Organic LEDs (OLEDs) are easier to manufacture but are not as robust as LEDs, and must be encapsulated because they are sensitive to oxygen and moisture.
Rogers and his colleagues have developed a method that creates bright, robust inorganic LEDs that can be processed en masse. Their approach produces thin inorganic LEDs in high quantities that are then cut into small pieces by soaking them in a strong acid. The pieces can be picked up with a stamp, with holes cut precisely to size for the elements, and placed on a variety of surfaces, including glass or rubber.
The pieces also can be placed sparsely enough that a bright layer of them is almost transparent. "Because you can get away with very low coverage by area, it opens up the possibility of making something that's see-through," Rogers says.
From BBC News
View Full Article
Abstracts Copyright © 2009 Information Inc., Bethesda, Maryland, USA 
No entries found