E Ink announces Kaleido 4 color e-paper display

E Ink has announced Kaleido 4, the next generation of its color e-paper display technology. Kaleido 3 screens are used in e-readers and tablets from companies including Kobo, PocketBook, and Boox. Amazon’s Kindle Colorsoft uses a customized version of the technology.

Kaleido 3 uses a color filter over a black-and-white e-paper panel. This allows faster refreshes than E Ink’s Gallery 3 technology, but color images appear at lower resolution than black-and-white text and can look desaturated. The filter also makes plain text look darker than on black-and-white E Ink screens.

E Ink says Kaleido 4 doubles its predecessor’s color gamut volume. The display remains limited to 4,096 colors, compared with the millions available on modern LCD and OLED screens, and still renders color at a lower resolution than black-and-white text. E Ink also says white reflectance increases by 15 percent and contrast by 50 percent.

A new oxide TFT backplane helps Kaleido 4 reach refresh rates of up to 18fps, which E Ink says makes video playback possible. E Ink has not announced new devices with the display. Hanvon Technology will be the first to use it, in its upcoming M10C II tablet, which will be available only in China. The tablet will have a micro-etched tempered-glass surface designed to reduce glare and provide a paper-like feel when writing with its battery-free pen.