"A unique aspect of these displays is that they are transparent," he said. "Until the pixels are activated, the display area looks like lightly tinted glass."
The nanowire transistors are made of a transparent semiconductor called indium oxide, a potential replacement for silicon in future transparent circuits. The OLEDS consist of the transistors, electrodes made of a material called indium tin oxide and plastic capacitors that store electricity. All of the materials are transparent until activated to emit light.
"This could enable applications such as GPS navigational displays right on the windshield of your car," Janes said. "Imagine having a local map displayed on your windshield so that you didn't have to take your eyes off the road."
The new OLEDs have a brightness nearly comparable to that of the pixels in commercial flat-panel television sets. The OLEDS have an average brightness of more than 300 candelas per square meter, compared with 400-500 candelas per square meter for commercially available liquid-crystal display televisions.
"Even in this first demonstration, we are fairly close to the brightness you'd see in an LCD television," Janes said.
The researchers also demonstrated they could create OLEDS of the proper size for commercial displays, about 176 by 54 microns, or millionths of a meter. OLEDS that size would be ideal for small displays in cell phones, personal digital assistants and other portable electronics.
|Contact: Emil Venere|