Fujitsu Bluetooth ring lets you write in the air

The gestural device goes on the index finger and can be used to write Japanese characters, Latin letters or numbers in midair. A linked smartphone or other Bluetooth mobile device with a Fujitsu app can instantly recognize numbers written with the ring with about 95 percent accuracy, according to developer Fujitsu Laboratories.

The ring can also be used to select items in a menu shown in a linked head-mounted display and to retrieve information from NFC (near field communication) tags.

It's mainly designed for workers doing maintenance or repairs, and allows them to quickly add written notes while working as well as call up cloud data such as schematics or instructions associated with pieces of equipment that have NFC tags. Often used in smartphones, NFC is a short-range wireless link that allows two devices or a device and an NFC tag to exchange data.

The chunky plastic ring houses motion sensors, an NFC tag reader and a Bluetooth Low Energy module in addition to a battery that lasts about eight hours. The prototype weighs less than 10 grams.

"This ring could be useful in very noisy work environments, for instance, where communication is difficult," said Yuichi Murase, a research manager at Fujitsu's Human Centric Computing Laboratories. "Workers can also use it to write notes on photos they take."

During a demonstration at a press event in Tokyo on Tuesday, a Fujitsu staffer wore a helmet-mounted display linked to the ring. He used the ring to write several Chinese characters, which are used in Japanese writing, such as "new" and "mountain" as well as the characters for "Fujitsu."

A linked laptop traced the movement of his index finger in the air as it went through the strokes. The characters were quite messy since they were drawn in the air, but the system almost always recognized them correctly.

The recognition technology developed by Fujitsu is able to distinguish and ignore the unwanted connections between the strokes. The more strokes a character has, the better the recognition rate, according to the company.

The development follows on the lab's development of a wearable in the form of a mesh-like glove. Unveiled in early 2014, the glove links with a head-mounted display to speed up maintenance work and in other applications where NFC tags are often used.

Fujitsu is continuing to test the Bluetooth ring with an eye to launching it for enterprise users by April 2016.