University of Tokyo is showing its flexible contact scanner (EW 08/09/04) at the International Electron Devices Meeting in San Francisco today.

It is "a flexible, organic image scanner which you can simply lay on a piece of text in order to take an image of the text", researcher Takao Someya of Tokyo's Quantum Phase Electronics Center, told Electronics Weekly. "The scanner is a thin, flexible sheet of plastic containing image sensors."

Each pixel in the device consists of an organic transistor and organic photodetector with an effective sensing area of 50x50µm and the 0.4mm thick imager has a 50x50mm sensing area and resolution of 36 dots per inch (dpi) "with the potential to go up to 250 dpi", said Someya.

The photodetectors distinguish between black and white by sensing the difference in reflected light from black and white parts of an image.

Its thin-film pentacene transistors have 18µm channel lengths and electron mobilities of 0.7cm²/Vs.

The IEDM presentation: 'A Large-Area, Flexible and Lightweight Sheet Image Scanner Integrated With Organic Field-Effect Transistors and Organic Photodiodes', will describe the device in detail.