Tim Stevens/CNET

TOKYO -- We've been seeing demos of Elliptic Labs touch-free gestures for some time now, but at Ceatec 2014 in Tokyo we got a fresh look at a new, more advanced implementation -- and some strong clues that this tech might finally be coming to market in the not too distant future.

Elliptic Labs uses ultrasonic sensors that, like a bat, emit high-frequency sounds (which a human can't hear). Those sounds bounce off a hand or a finger and, by calculating how quickly the sound returns and at what frequency, the Elliptic system can detect position in 3D. Add years of fine-tuning, plus plenty of custom software, and you have the ability to recognize gestures made in thin air.

We got a demo of this technology at CES 2013, embedded in a laptop running Windows 8. This time the demonstration was on a mobile device, specifically a Samsung Galaxy S4 . Now, the S4 lacks the required ultrasonic transducers to enable the Elliptic system, which is why you can see it grafted with a bulky box in the photo above. (This is the developer kit, available for those who want to write mobile apps that will use the Elliptic system.)

Elliptic's latest system can not only detect a hand in front of the screen, but specifically its distance relative to that surface. So, you can sweep up or down or also push inward and outward.

Elliptic has a number of demonstrations to share, including a lock screen widget that shows your calendar appointments when your hand is far away, emails when your hand gets closer before finally switching over to the lock icon when you're close. We were also able to lock the screen simply by "tapping" twice in midair and swipe through a photo gallery by waving our hand about with noble dignity. Everything worked and worked well, despite the constant drone of a busy exhibition hall.

The concept isn't that different from those seen by Leap Motion and others, but there's particular promise here on smartphones and, some day, smart watches. The field of interactivity is far larger that the device itself, extending out to 180 degrees around, and works just as well whether you're wearing gloves or even those cat paw mittens they sell in Harajuku.

Tim Stevens/CNET

Adoption for device makers should be relatively easy, thanks to a Murata-made transducer that's just 5.2mm square and consumes less than one milliwatt of power. That means phones won't need to get much bigger to make this work, and having it on all the time won't kill your battery life.

The question, of course, is when those manufacturers will actually start using it. While Elliptic Labs CEO Laila Danielsen wouldn't give us any details, she did indicate that "more than one" mobile device manufacturer has licensed the tech, and that it will be appearing on both smartphones and tablets in 2015. Windows support remains, but it seems like the big push going forward will be Android. Could the choice of a Samsung phone for the dev kit have some deeper meaning? We'll have to wait and see.