British inventor James Dyson came up with the idea of augmented reality smartglasses more than a decade ago, according to design documents revealed today on his Facebook page. 

To mark his company's 21st birthday yesterday, Dyson released three never-seen-before ideas and one of them bears an uncanny resemblance to Google Glass.

Dyson Halo, an augmented reality headset that was codenamed N066 and was admittedly much clunkier than Google Glass, was one of the ideas that failed to see the light of day.

The invention boasted a full colour 3D display projected from an arm at the side of the user’s field of vision, along with a mic and camera.

Dyson envisaged that the heads-up display would use two mirrors to reflect the display of twin mini-monitors to produce the effect of a 10 inch screen a metre in front of the user's eyes.

Dyson's headset was designed to wrap around the back of the head and connect via a cable to a small computer that was designed to sit in the user’s pocket or clip onto their belt. 

Google Glass, first announced in 2011 and eventually released to a handful of "Explorers" in 2013, uses a prism mounted above the eye to display information while the computer component of the device is mounted on one of the ear stems.

Dyson Halo also featured a Siri-style virtual assistant that could process basic voice commands, and a wrist-worn control pad to guide a mouse pointer around the user interface.

The designs suggest the device would have a 1GHz chip and 256MB memory, alongside a 20GB hard drive – with the potential to link to the cloud. 

Unlike Google Glass, the Dyson Halo computer module could detach from the glasses and plug into a normal monitor to work like a traditional desktop.

Glass is yet to go on sale to the general public and some people feel Google needs to make a host of improvements before rolling it out.

Dyson's other ideas included a trap to capture harmful diesel particles and a fuel cell.