Tech giant Google has been granted the patent for glasses with a built-in projector.

While laser-projected virtual keyboards have been seen before, a projector which is part of a pair of glasses is a new thing. This week, the US Patent Office granted Google's patent under number 20130016070.

The technology means that a laser can be built into the frame of a pair of glasses and this laser will project a keyboard onto a chosen surface. The user can then use the keyboard to make commands.

One expert writing for Decrypted Tech said: “This could be an excellent alternative to voice commands, head tracking and other systems that Google plans to incorporate into their smart glasses.”

Industry insiders have noted that Google is clearly determined to protect this latest projector technology, even though it isn’t clear whether it will even feature in the first iteration of the glasses, due out in 2014.

Some have speculated that Google glasses with a built-in projector will only be available in later versions because Google has not specifically mentioned this feature when talking about the glasses. However, other industry analysts have suggested that a surprise from Google is not out of the question.