15 Feb 2011
Lens arrays, pico projector engines, 3D technology and wafer-level cameras show that the handset industry is anything but commoditized when it comes to optics.
Trying to get a hotel room in Barcelona on Valentine’s Day is tough. And that has less to do with romance than you might think – this is also the week that the Mobile World Congress (MWC) traditionally arrives in town, complete with 1300 exhibitors and 50,000 attendees.
And although you might not immediately think of optics as a key driver of the mobile handset industry, this is yet another sector where it has proved to be an important enabling force. LED backlights, organic LED touch-screens, built-in cameras - all these are fundamentally photonic innovations that have proved pivotal to handset evolution and market growth.
So what should we expect next? Judging by recent announcements, including those from some of the biggest companies in the industry, that there is plenty more optical innovation on the way – and that handsets are far from a commodity market for photonics companies whose technology can give a handset a distinctive edge in either function or design.
One of the highest-profile announcements at this week’s MWC has been LG’s launch of the first handset with a 3D display - moreover, one that does not require its owner to wear any 3D glasses. But the LG Optimus 3D doesn’t just play 3D content; a dual-camera arrangement enables users to generate 3D content themselves (perhaps because there is actually very little existing 3D video content for mobile users right now). This has been highlighted by a recent deal between LG and YouTube designed to help proliferate home-made 3D video.
Major movers in pico projection
Like 3D video, pico-projector technology is yet to really penetrate the mainstream, despite the plethora of companies working on the technology.
Analysts at Pacific Media Associates suggested recently that a market of 22 million pico projectors would emerge by 2014 – up from only 700,000 in 2010, but barely a blip in a handset market that has already reached in excess of 1.6 billion units annually. But new developments of note at MWC in 2011, including moves by the technology giants STMicroelectronics and Texas Instruments, suggest that they, at least, see a significant market for pico projectors finally emerging.
Texas Instruments’ DLP Pico chips, based on the company’s long-standing digital light projection (DLP) technology, sit at the heart of many early pico projector designs, and the company used MWC to reveal a new chipset that provides brighter images and lower power consumption (a crucial factor for projectors drawing a current through multiple LED or laser sources to deliver high-brightness images).
According to Frank Moizio, manager of TI’s DLP Pico Projection unit, the latest generation of the technology can provide an image up to 50 inches across on any surface (given ideal lighting conditions), and is now so small that it goes virtually undetected in current handset designs.
Meanwhile STMicrolectronics said on the eve of the Barcelona event that it had signed a development and license agreement with the Israeli company bTendo to deliver “the world’s smallest pico projector for smart phones”.
This approach will be based on bTendo’s scanning laser projection engine, which uses individual red, green and blue laser diodes in combination with a spatial modulator and scanning mirrors. Key to the whole design is the pair of MEMS-based mirrors that project the image onto the nearest surface – and which STMicroelectronics will provide.
Bill Coggshall, the president and founder of Pacific Media Associates, hailed the agreement as a “major milestone” in the development of a significant market for embedded pico projectors, forecasting that the impact would be felt within two years – perhaps enough for direct green laser diode technology to reach an acceptable cost point for volume applications.
While innovation might be expected for such radical functionality as an embedded projector, it seems unlikely that the make-up of the lens itself would represent an opportunity for photonics companies to make a mark in handset applications. But it turns out that this is not the case – a handful of companies are targeting the smart phone market with radical technologies.
Varioptic's liquid lenses have been around for a while – and, as yet, they are yet to make a major impact in handsets, despite their ability to mimic the human eye by changing focus and direction quickly through electrowetting instead of using any moving parts.
Launched at last year’s MWC and also shown off at Photonics West last month was Varioptic’s latest innovation – an image-stabilizing lens that compensates for the natural shaking of the handset when taking a photo or video footage on a handheld device. Varioptic’s new CEO Hamid Farzaneh says that it is aiming to penetrate the smart phone market – now worth hundreds of millions of units each year – with the new technology.
Meanwhile Pelican Imaging, a venture-backed start-up based in Silicon Valley, is also targeting smart phone manufacturers with a new kind of lens, this time a computational array camera that it claims improves image and video quality while also enabling thinner handset designs.
Gesture control in a handset
Investors (including the CIA-backed In-Q-Tel strategic investment firm specializing in intelligence applications) seem to agree, having backed Pelican to the tune of $17 million since its inception in 2008. The company has also just recruited three new members of a technical advisory board, in the form of Google’s former Street View project leader Marc Levoy, Shree Nayar from the Columbia Computer Vision Laboratory and technology consultant and pixel sensor pioneer Bedabrata Pain.
Pelican says that its camera array technology will enable features such as 3D depth and gesture control to be integrated within a smart phone, overcoming what have traditionally been the limitations of the handset format.
Levoy said of Pelican’s approach, which includes 12 pending patents, “The technology has the potential to upset the traditional trade-off between the sensitivity and resolution of a camera and its thickness,” and adds that future applications might include post-capture focusing, foveal imaging and programmable frame rates.
“We have been investigating these aspects of computational photography in our laboratory at Stanford for a number of years, through the Stanford Multi-Camera Array, which is big, slow and expensive,” noted Levoy. “Pelican’s solution is small, fast and inexpensive – which makes it a very exciting technology.”
One company with a more prosaic approach to handset cameras is Nemotek Technologie, whose wafer-level technology was initially licensed from Tessera and largely confined to packaging. However, the company, which is based in Morocco and backed by a major pension fund, has more recently started branching out with its own optics technologies, and now has a wafer-level camera offering.
Out of Africa
Operating out of Africa’s very first Class 10 clean room, at the Technopolis Park in Rabat, Nemotek now has an in-house optical design team capable of developing customized wafer-level cameras for high-value uses such as automotive or medical applications, where attributes such as a wide field of view are important.
Despite the unusual location – Morocco has very little in the way of a photonics industry – Nemotek is actually in a pretty good location to service the European and Middle East markets for high-end phones. After all, Rabat is about the same distance from Barcelona as Paris is.
Ali Elyazghi from the company told optics.org that Nemotek’s wafer-level camera technology would help to make sure that new approaches – such as the use of two cameras in a single handset – could be produced in a smaller size. Nemotek has also developed novel two-element lenses that enable a wider field of view. Elyazghi added that the wafer-level approach could potentially be compatible with liquid lenses, which have proved difficult to manufacture in the kinds of volumes needed for the mobile handset industry.
As far as the consumer interest and commercial success of pico projectors and 3D cameras are concerned, the jury is still out – maybe these applications will capture the public’s imagination, and maybe they won’t. But what can’t be argued is that optical ingenuity remains intrinsically linked with handset form and functionality, and continues to prove itself as a truly enabling technology.
About the Author
Mike Hatcher is the Editor in Chief of optics.org