One of our best hints as to how Google's Project Glass will be controlled was from The Gavin Newsom Show, where Sergey Brin used an input panel on the side of the glasses to apparently flip through photos. Google has now been granted patent protection covering this kind of "integrated finger-tracking input sensor device" on the heads-up display. The patented system would have a trackpad-like section on either side of the glasses, one allowing for fine motor control and the other for broader movements. These could be made of plastic, glass, or metal oxide, and left-handed users could swap which side managed fine control.

Google references different gestures that could be made on the tiny pads and says they should be translucent or transparent to allow for peripheral vision; the use cases it describes include scrolling, flipping through options, and double- or single-tapping to select. It's never called a trackpad, however, and there's no mention of something like a mouse-style cursor. The patent was filed on May 25th, 2011, over a year before Brin's demonstration and well before Google filed for protection on infrared ring-based motion controls for Glass. The glasses are expected to ship next year at the earliest, so we're certain to see changes before they're even out of prototyping.