At CHI 2009 (computer Human Interaction conference,) many new modalities of
interface were demonstrated. Some were sublime, some ridiculous.
One of the more practical, was the product of a team from ETH Zurich's Wearable
Computing lab. Vaguely resembling the bastard child of a set of safety glasses
and a HMD, the EOG goggles are an eye movement tracking system, that requires
no external hardware to operate.
The prototype might look a tad convoluted, but it is an elegant solution to
eye tracking, that is cheap to create, and lightweight to wear. Refined units
could very easily be quite streamline.
EOG or electrooculography is a way or measuring the resting potential of the
retina of the eye. It is usually a way to measure the position of the eye. Electrodes
on either side of the eye are exposed to more or less of the retina as the eye
moves. The difference in potential between the two, showcases the degree of
movement of the eye, and thus where it is looking. With electrodes positioned
above, below, and to either side of the eyes, the goggles can accurately calculate
horizontal and vertical movements.
The technique can also be used to determine the brightness of ambient light,
by measuring reflection off of the retina before it adjusts.
The benefit is that no video tracking is required, greatly reducing both weight
and processing power in one fell swoop.