Projectors Invade Cellphone

Tomorrow's cellphone could generate, play and even project high definition video. Those concepts, along with a hope that consumers will buy multiple phones for different uses and occasions, were on vendors' minds at the Consumer Electronics Show. 3M, Microvision Inc. (Redmond, Washington) and Texas Instruments showed at CES tiny projection modules they aim to get designed into cellphones this year. National Semiconductor is working on a similar device.

The cool factor is high for having a phone that projects a video or picture on a wall, a piece of paper or a friend's shirt. But analysts remain skeptical given the relatively high power consumption and low light output of devices that have been discussed so far.

TI is shipping its DLP Pico Projector module which it claims will appear in a Samsung phone in Korea in January. The device already powers handheld projectors from Dell, Optoma and Samsung. The TI module is a 44.8 x 67.4 x 14.2 mm device that can create a half VGA display (320x480 pixels) at up to 7.5 lumens in brightness. It uses a version of TI's digital light processor chip with 300,000 micro-mirrors. A TI system using the device consumes up to 3.5W.

3M is sampling its MM200, a second-generation of its LCOS-based module released a year ago. It is similar in size and brightness to the TI module, but can deliver a full VGA (640x480) image and can draw as little as 1W at the module level, according to the company.

Microvision's Integrated Photonics Module consists of lasers and MEMS on a tiny board with batteries. It is roughly the same size as its competitors at 60 x 68 x 10 mm but delivers resolutions up to 848x480 and brightness up to 10 lumens. However, it will not ship until the second half of the year. Microvision sells a full system also called the Pico Projector which consumes 3.5W. Its embedded module, expected to ship by June, will consume 1-1.5W.

In December, Brian Halla, chief executive of National Semiconductor, told EE Times his company will ship late this year a tiny projector using an array of red, green and blue lasers. It will project 12 lumens of light and draw less than 1W, said Halla.

The designs of both Microvision and National are waiting on green lasers from suppliers including Corning and Osram. Osram is said to be expanding its green laser production capacity by mid-2009.

A TI spokesman said the reflective nature of its micro-mirror approach is more energy efficient than the LCOS approach from 3M. Microvision said its module is unique because it uses a single beam of light to project still or moving images.

"It's always in focus. No lens is needed," said Matt Nichols, a director at Microvision. Further, "It can project images onto a variety of surfaces " including a hand, shirt or any surface," not limited to a flat white wall.

At the heart of the Microvision module is a MEMS scanning mirror. The tiny mirror is connected to small flexures allowing it to oscillate. The MEMS scanner oscillates vertically and horizontally, scanning the modulated laser beam to generate an image pixel-by-pixel, according to the company.

Tim Barajin, principal of consulting firm Creative Strategies (Cupertino, Calif.) said the modules he has seen to date are too dim. He called for devices that can generate more than 10 lumens and still fit into the power budget for a cellphone component, which typically is limited to a couple hundred milliwatts.

Broadcom engineers believe creating and playing — not necessarily projecting — high def content is the next big thing for handsets. The company showed its BCM2727 at CES handling encode and decode of 720-progressive video at 180 milliwatts. The device also handles imaging at up to 12 Mpixels. It comes with third-party facial recognition software for a camera phone that can automatically decide when to shoot based on detecting blinks and smiles. The chip also contains a 3-D processing block to play mobile games. It comes in a package with a 32 Mbyte stack of memory.

"We can do six hours of HD video encode on a normal cellphone battery, you needed a car battery for that in the past" joked Scott McGregor, chief executive of Broadcom.

Separately, LG Electronics showed an audio feature it hopes will drive sales of its handsets in 2009. The cellphones use two microphones and a noise cancelling algorithm to eliminate ambient noise when a user is making a call from the street or a crowded room.

"We will have the technology in many of our cellphones in the second half of the year," said Ehtisham Rabbani, vice president of product strategy for mobile phones at LG.

By Rick Merritt and Junko Yoshida, EE Times