When it comes to entering data into a digital device, the clackety old keyboard still beats alternatives such as voice or handwriting recognition. Trouble is, the keyboards on the latest wave of mobile PDA/phones from companies like Research in Motion and Handspring literally make typists all thumbs.

Virtual keyboards may change all that. Three competing companies-VKB of Jerusalem, Israel, Canesta of San Jose, CA, and Virtual Devices of Pittsburgh, PA-are selling products that use lasers to project an image of a full-sized QWERTY keyboard on a flat surface. Optical sensors then track the user’s finger movements and translate them into keystrokes on a screen. The owner of a mobile gadgets equipped with such a keyboard could prop it up on a seatback tray or a briefcase and type away, eschewing a full laptop or a collapsible keyboard.

The machine-vision software that goes into such systems is so complex that it could easily handle other tasks such as facial recognition. But Canesta, for one, “honed in on the keyboard because we thought it was cool and also extremely marketable,” says Cyruis Bamji, the company’s chief technology officer.

You’d need both hands to count the methods inventors have proposed for typing without keyboards. Pressure-sensitive gloves, finger rings and “air” gloves that use fiber optics to detect finger curvature are among the many that will never leave the lab. But once other manufacturers started making tiny, low-cost optical sensors, Canesta’s engineers were convinced they had the answer, says Bamji. “We knew that optics had to be compromised to be small, so we had to figure out if the software and electronics could make up the slack,” he says. The key, so to speak, turned out to be new  software algorithms for mapping finger movements in three dimensions. Canesta chipsets carrying the software will turn up in stand-alone accessories and high-end cell phones and PDAs by the end of 2003, Bamji says. A projection-keyboard accessory including VKB’s technology could appear even earlier.

But will mobile device users take to these make-believe keyboards? Testers at Canesta claim focus group participants adjust to flat typing in about 15 minutes. Touch-typists, however, will miss the tactile feel and feedback of an actual keyboard, and users will have to pay close attention to the keyboard image to reduce errors by the mapping software. Donald Norman, an interface design expert and co-founder of Nielsen Norman Consulting, doubts virtual keyboards will sweep the market, though he thinks they will have their uses. “If you don’t have much typing to do, it’s fine,” says Norman. “I’m not saying it’s a bad idea-it’s just an idea for limited circumstances.”