The telephone, which was only on show as an engineering prototype, looks like a watch phone. That's futuristic enough, but several companies, including NTT DoCoMo Inc. and South Korea's Samsung Electronics Inc. have already developed those. Where the DoCoMo phone departs from James Bond-type telephones is in the way the user interacts with it -- much more than with just a telephone worn on the wrist, the user's body becomes an integral part of the device.
Most of this interaction takes place via a sensor mounted on the underside of the user's wrist. The sensor includes both a speaker and a microphone, the former pointing inward and touching the skin while the latter is mounted facing outward.
When a call is being made the user inserts their finger into their ear. Sound travels via bone and cartilage from the wrist to the finger and then vibrates through to the ear, where it is picked up, explained Masaaki Fukumoto, a senior research engineer at NTT DoCoMo's Media Computing Lab and the developer behind the system.
The result? Callers sounds a little distant, and the volume is low, but it definitely works!
The microphone is more conventional and simply picks up the voice of the person speaking because, with their finger in their ear, the underside of the wrist is naturally close to the mouth.
The final innovation comes in control of the telephone hook. A call can be started or stopped by tapping your second finger and thumb together with different rhythms signifying either the beginning of a call or hanging up. The same system cannot yet be used to dial yet -- the prototype doesn't even have a keypad, but in the future, the user could tap the second finger and thumb in certain patterns to control dialling and other functions.
Fukumoto, who is part of a six-member team that works on wearable technology at the cell phone operator's research and development lab in Yokosuka near Tokyo, cautions that the cell phone might never come to market but that some of the technology being worked on now may well make it into cellular telephones of the future.
NTT DoCoMo, in Tokyo, can be found online at http://www.nttdocomo.co.jp/.