U.S. Patent and Trade Office

Among the challenges developers will face when they start building for Google Glass this year is a basic one: how do users communicate with the device?

Glass has a microphone, and a button for taking pictures. But what if the user is in a noisy environment, or wants to create a long message? Is there any way to include a keyboard?

The answer is yes, according to an intriguing new patent application filed today with the U.S. Patent and Trademark Office. Patent 20130016070, "Methods and Systems for a Virtual Input Device," shows a version of glass that includes a laser projector in the arm of the glasses. The glasses project a keyboard on to the hand of the user, who can than use his body as a touch screen.

As noticed by Unwired View, the patent describes a use in which the glasses' camera interprets a user's gestures, so that they can accept input both via tapping virtual keys and by moving the hand.

It's only a patent application, of course, and there's no telling whether the ideas described will ever make it into a product. But it does show that Google engineers are thinking hard about the Glass' input problem, recognizing that for wearable computing to go mainstream it will likely need to expand beyond voice control. Laser-projected keyboards could be one way to make that happen.