Optical mice use imaging and digital processing technology to track movements with a spatial precision of about 1000 dpi.
Today’s invention is a range of new uses for this technology, based on moving some surface across a stationary, inverted mouse -or at least the optical internals thereof.
This might enable a system, consisting of an array of such sensors, to recognise large scale hand gestures or, if embedded in a car headrest and steering wheel, it could record movements of the driver’s head and hands (as mentioned here).
The technology might be employed to record eg the number of times a particular door opened.
As a measure of audience engagement, the technology might be embedded in the seats of an auditorium or a cinema in order to record the frequency and extent to which people shift their seating positions. Imagine the dollar value of knowing exactly which ten minutes to edit out of a movie, based on the movements of its test audience.
With practice, it can even record the number of eyeblinks per second and drive an on-screen cursor by following, albeit crudely, eye movements (don’t try this at home).