A newly filed Apple patent application suggests the company is still working on a Kinect-style 3D motion tracking system, that could create a virtual desktop responding to a user's hand and finger movements rather than keyboard and mouse actions. The application, Three-dimensional imaging and display system, describes a system where "user input is optically detected in an imaging volume": in short, both of a user's hands are tracked in the space around an Apple computer, and on-screen or projected virtual controls - such as dials, buttons or pens - can be manipulated as if touching them in real life.
The system would operate "by measuring the path length of an amplitude modulated scanning beam as a function of the phase shift thereof" while simultaneously "visual image user feedback concerning the detected user input is presented" Apple's document suggests. A more simple implementation might track movement in 3D space around the computer and simply show the results on-screen; however, Apple's application also suggests that audio feedback could be used, such as a clicking as you rotate a virtual knob, or a 3D display using a complex system of projections and mirrors.
Exactly how practical such a setup might be would depend on the intended portability of the computer itself. While a projection box of some sort makes sense with a desktop rig, it could prove cumbersome when tethered to a MacBook Pro, for instance. In that situation, straightforward on-screen controls navigated via gesture would perhaps make more sense.
Apple also envisages the system potentially being integrated with head-tracking, either using angle of gaze or other motions to trigger functions like scroll and zoom, or implementing a motorized camera to keep the user in-view, along with user-presence detection. The 3D display system could also be slaved to a smaller device, such as an iPhone or iPod, to augment the portable gadget's own, smaller screen and "thereby considerably enhancing the usability of the device, and substantially enhancing and improving the user experience."
An actual 3D display and the associated user-tracking is obviously not expected any time soon by Apple, despite what the company's engineers appear to be working on now. This latest patent looks to be a modified version of one, also by Apple, granted back in September. At the time, it was speculated that the tech would allow the company to integrate 3D displays and complex gesturing with mobile devices.