With all the ‘ possibly misguided ‘ excitement about ‘smart watches’, Qualcomm may have reawakened its interest in its ultra-low power display technology, Mirasol. Last year, the company backed away from direct commercialization of the MEMS-based system, though it suggested it could license it to partners. But it was demonstrating the latest iteration of Mirasol very visibly at the SID Display Week event in Canada, and company representatives said it could turn up in small-screen devices (about 1.5 inches) this year.
That could point to the smart watch launches that many are expecting from Samsung, Microsoft and even the Apple ‘iWatch’. Though Samsung and LG have sold cellphone/watches for several years, they have never been a mainstream category, but they would be a strong target for Mirasol, which has mainly been implemented in small sizes and reportedly struggled to scale up to full smartphone or tablet sizes.
However, the prototype demonstrated at the show suggests that, while commercial launches this year may be in the small-screen sector, Qualcomm has overcome some of the challenges of adapting its technology for larger displays and also for full color. It was showing a 5.1-inch screen boasting massive resolution of 2560 x 1440, which means pixel density of 577 per inch (this compares with 440 ppi on a full HD 1920×1080 display such as that on the newest Samsung Galaxy 4S).
As well as high resolution, Mirasol’s chief claim to fame has been its very low power consumption, which can be as much as six times better than LCD or OLED smartphone screens. It uses ambient light and MEMS (micro-electromechanical systems) to create small air gaps ‘ as their size changes, the light color passing through is manipulated. They provide very clear visibility in sunlight or in limited light, though colors can be rather washed out, say critics.
One factor behind the revival of Mirasol may be Qualcomm’s recent alliance with Sharp. A factor behind its decision to take a stake in the ailing Japanese display maker last year was the opportunity to collaborate on modern MEMS screen technologies. It said at the time that it would broaden its existing pact with Sharp to ‘develop and commercialize high quality color, low power MEMS displays incorporating IGZO.’ Sharp has pioneered IGZO (Indium Gallium Zinc Oxide) technology, which supports very slim displays using existing LCD manufacturing processes.
This joint effort has mainly focused on speeding up commercialization of another Qualcomm technology, low power MEMS displays acquired with Pixtronix, by combining the technology with IGZO, and harnessing Sharp’s display manufacturing resources. The same advantages could be applied to Mirasol, addressing Qualcomm’s past problems with translating clever technology to mass commercial production in a sector where it lacks experience (though it did, at one stage, invest in manufacturing capacity for Mirasol).
Qualcomm acquired Pixtronix in early 2012 for a sum reported to be around $190 million. The smaller company’s display, PerfectLight, is based on a digital micro shutter which modulates light from an RGB LED backlight (unlike Mirasol, which harnessed ambient light). It uses MEMS instead of liquid crystal to control light transmission, which greatly reduces power consumption. High switching speed makes it suitable for full speed video, says the company ‘ a failing of Mirasol. PerfectLight claims to support greater than 170-degree viewing angles, more than 3,000:1 contrast ratio and 24-bit color depth ‘ all at 25% of the power consumption of LCDs with equivalent size and resolution.