The United States Patent and Trademark Office (USPTO) published Google's patent application for Google Glass. Aside from technical drawings of its futuristic visor model, a version of Google Glass that resembles a pair of thick-rimmed hipster glasses is also evidently in the works. This could be the version that Google is designing for people who already wear glasses — it might even allow the possibility of prescription Google Glasses.

Some points of interest:

The application describes the possibility of one or more touchpads mounted on the earstem, or elsewhere: "The finger-operable touch pad 124 is shown on the extending side-arm 114 of the head-mounted device 102. However, the finger-operable touch pad 124 may be positioned on other parts of the head-mounted device 102. Also, more than one finger-operable touch pad may be present on the head-mounted device 102."

This means a touchpad in addition to head-tilt controls is definitely in the works, but the additional weight and bulk could make it unappealing for those who like the sleek look.

Google also mentions the limitations of its video player, TechCrunch notes. Instead of playing movies directly, the glasses play media from other devices, rather like a computer monitor.

The patent also shows that the Glasses frame will be constructed of either metal or plastic, which will be hollowed out to make room for wiring and other internal components. The prism on which notifications will be displayed need to be both transparent and a surface onto which information can be projected.

Aside from the lens we currently see on Google Glass, the application brings up the possibility of a laser or LED that would project a display directly onto the user's eyeball. We're not too sure about the health consequences of this, but it would be interesting to see in practice (assuming it won't burn the image onto your retina if you leave it on too long, like a computer whose user forgot to set up a screensaver).

Notably, while the Google Glass is designed to be a stand-alone device, it should be able to connect to and receive input from a peripheral that can transmit information to it, whether a tablet, laptop or cellphone. Both wired and wireless connections could be possible.