If you are new to electronic paper, check out
this Digitimes article which gives a comprehensive overview of current e-paper technologies.
Electronic paper types: Electrophoretic, cholesteric LCD (Ch-LC) and OLED (organic light-emitting diode)
Electrophoretic
Companies working on electrophoretic e-paper: US-based E-Ink, UK-based Plastic Logic, Netherlands-based Polymer Vision, Japan-based Bridgestone, Hitachi, Seiko Epson, Taiwan-based Prime View International, Korea-based Samsung and LG.Philips LCD
Current products: Citizen E Ink Watch, iRex iLiad, Jinke Hanlin eBook V, Seiko bracelet watch, Sony Portable Reader, eRead STAReBOOK, 10-inch 150ppi flexible displays by Plastic Logic (in 2008), 14.3-inch flexible color e-paper by Samsung Electronics, 14.1-inch flexible color e-paper by LG.Philips LCD, 1.9-, 6- and 9.7-inch flexible active matrix (AM) displays by Prime View International
Contrast ratio: 10:1
Colors: 4096
Pricing low
Technology barrier: low
Cholesteric LCD (Ch-LC)
Companies working on cholesteric LCD e-paper: US-based Kent Display, Kodak, Taiwan-based Industrial Technology Research Institute (ITRI), Japan-based Fujitsu Frontech
Current products: 10.4-inch bistable name card by ITRI, 12-inch and 8-inch FLEPia portable information terminal by Fujitsu Frontech
Contrast ratio: 10:1
Colors: 4096
Pricing low
Technology barrier: low
OLED
Companies working on OLED flexible e-paper: Korea-based LG.Philips LCD, Japan-based Sony
Current products: 2.5-inch color OLED by Sony, 4-inch full-color flexible active matrix (AM) OLED by LG.Philips LCD
Contrast ratio: >10,000:1
Colors: 16m
Pricing high
Technology barrier: high