E Ink has announced Kaleido 4, the latest version of its Kaleido color e-paper technology, with improvements that could define future e-readers and writing tablets. The display is designed to produce a wider range of colors, and the company says it "doubles the color gamut volume" so it can show over 40,000 colors. It also reports higher white reflectance and better contrast.
Refresh rate has long been a weakness of e-paper screens. E Ink says Kaleido 4 can display video content at 18 fps. That figure sounds modest next to the 120Hz OLED screen in many smartphones, but it is meaningful for e-paper, which typically refreshes slowly. The company credits an oxide backplate added to the display stack for the faster refresh, a change Amazon also made to the Kaleido screens in the original Kindle Colorsoft.
E Ink's panels are used by major e-reader makers including Amazon, Kobo and Boox. If Kaleido 4 delivers, future devices could show more accurate color images without sacrificing much clarity in black and white text. Text on older Kaleido 3 displays can look fuzzy, which is one reason some companies have chosen E Ink's Gallery 3 instead. Gallery displays use colored pigments for richer images and text, but they take longer to refresh.
For now, Kaleido 4 appears in only one device: Hanvon Technology's M10 C II. The e-paper tablet is available only in China and includes a redesigned front light and micro-etched glass that gives a more paper-like feel when writing. How much better Kaleido 4 performs than earlier Kaleido displays will become clearer once the screens can be compared side by side.
Source: Engadget · Summarized by HeadlinesBriefing