The Mirasol technology being developed by Qualcomm hasn’t gotten a whole lot of attention, but it has come a long way and could be a viable contender for ereader displays this year. Qualcomm MEMS Technologies (QMT) is working with Taiwan’s Foxlink Group to begin commercial production of 5.7″ color displays by the end of the year.
I sat down with Cheryl K. Goodman, QMT director of publisher relations, for a hands-on session with a prototype device. Mirasol imitates the way a butterfly’s wings produce color through light interference. Like E Ink and other electrophoretic displays, it is reflective and bistable. That means it depends on external sources for light and consumes power only when the screen is being redrawn. Once drawn, the screen will display an image indefinitely without power. But developing electrophoretic color has proved to be a big challenge, as has redrawing the screen quickly enough to handle video.
The prototype was an impressive indication of how far Mirasol has come from the postage stamp-sized two-color displays of a couple years ago. When displaying static text, the Mirasol screen looks a lot like an Amazon Kindle or other E Ink reader–dark grey text on a lighter grey background. Color images were a bit undersaturated and a good bit less vibrant than an LCD display, but certainly acceptable. Video, at 15 frames per second, was less than overwhelming, but QMT hopes to get to the standard video rate of 30 fps the time the product ships. The screen could be viewed from a fairly wide horizontal angle, but the acceptable vertical viewing angle was a lot narrower.
QMT says that battery life is actually somewhat better than E Ink in a static text display and 3.7 times that of an LCD. Cost is still to be determined and could be an issue. The good news is that Mirasol displays can be manufactured using semiconductor technologies on modified versions of the equipment used to fabricate LCD displays, creating the potential for rapid price declines with volume production.
The likeliest use for Mirasol displays would be in ereaders that incorporate color images and some video.