Google has unveiled futuristic prototype eyeglasses that offer a heads-up display with a connection to the internet.

Dubbed "Project Glass," the fashionable and discreetly designed specs project icons and images within the wearer's field of vision and allow voice-activated control and communication.

In a video demonstration, a wearer is shown in a daily routine while checking the weather, reading and sending messages, taking and sending photographs and participating in a video chat.

"We're sharing this information now because we want to start  a conversation and learn from your valuable input," Google says in a post on a Google+ page devoted to Project Glass.

The glasses will be tested in public by the company's development team, but Google has not said when they might be sold or at what price.