E-book readers-handhelds that display the contents of book files downloaded from the Internet-just got a whole lot more readable. Philips Electronics and Cambridge, MA-based E Ink have developed a prototype electronic display that looks like paper and ink, not a dim, fuzzy screen. The device uses E Ink's tiny fluid-filled balls containing oppositely charged black and white particles, which are layered in a thin film on a sheet of plastic or glass. Connecting this film to electronics allows the reader to display text and graphics by controlling the voltage across each ball, determining whether it appears black or white. The result: higher contrast than newspapers and better resolution than laptop screens. The 15-centimeter-diagonal display is about half the weight and thickness of comparable liquid-crystal readers. It has been in the works for a few years, but this is the first version that is ready for commercial production. Look for the new readers to hit shelves later this year.