A recent patent application shows some ideas from Apple on immersive glasses-free 3D displays-- with the sketches of a system gauging depth to display 3D images by tracking user eye movements.

Titled "Three Dimensional User Interface Effects on a Display by Using Properties of Motion,” the patent suggests the use of device compass, GPS, accelerometer and gyrometer to calculate the viewer's frame of reference. All these sensors add to a front-facing camera handling eye tracking duties.

The theoretical system even factors ambient lighting in the whole 3D view equation, and can also find implementation in desktop displays.

Currently Apple sells no devices with 3D displays. The only current mobile device carrying a 3D display worthy of note is the HTC Evo 3D, which uses parallax barrier for glasses-free 3D.

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