Seiko Epson Develops 200 ppi Definition Flexible E-paper

May 30, 2005
A picture of the prototype shown during an oral paper presented by Seiko Epson
A picture of the prototype shown during an oral paper presented by Seiko Epson
[Click to enlarge image]

At the SID International Symposium, Seminar and Exhibition "SID 2005" held in Boston, US, Seiko Epson Corp. announced in an oral paper (paper number: 54.3) the development of a flexible high definition 200 ppi display. The resolution of a 2-inch display extends to 320 x 240 pixels. The display used an electrophoresis electronic paper developed by E Ink Corp. Seiko Epson "aims to commercialize the technology within 1-2 years" targeting such markets as handheld products.

To enable dot display, low-temperature polycrystalline Si thin-film transistors (TFT) are used in the driver. The company secured flexibility of the driver by introducing its proprietary SUFTLA technology, which transcribes TFTs formed on a glass substrate onto a plastic substrate. A gate driver IC and a source driver IC are also formed on the same low-temperature polycrystalline Si TFT substrate. "We intend to realize a flexible display system with higher levels of integration by adding other devices including a DC-DC converter, a charge pump and a microprocessor onto a single substrate," said a company spokesperson.

Seiko Epson did not actually display the prototype, but showed its photos of it while delivering the oral paper. The prototype's contrast ratio is more than 10:1, thickness is 375 μm, and weight is 1.2 g.

Takuya Otani, Nikkei Electronics