Abstract: An eye tracking system employing three-dimensional (3D) sensing using time of flight is provided. Instead of directly measuring the time of arrival of the emitted photons, the light intensity of the transmitted laser beam is modulated, and a phase change of the return beam computed by comparison with the transmit waveform. The modulation frequency is resolved with radio frequency (RF) mixing and digital signal processing techniques. A variety of phase detection systems and techniques including, but not limited to, quadrature analog front end detection and analog homodyne phase detection are applied. The modulation frequency may, depending on phase detection technique, be sinusoidal or pulsed.

Abstract: An eye tracking system for absolute phase unwrapping includes a fringe projector, a camera, and an illumination module. The projector provides a periodical fringe pattern onto the eye and the camera captures a reflection of the fringe pattern. Fourier transform, wavelet transform, phase shifting, and/or variants thereof may be used to determine a phase of the fringe pattern and generate a wrapped phase map. Spatial phase unwrapping is used for phase unwrapping resulting in a relative unwrapped phase map. The illumination module with a known relative position between the fringe projector and the camera is used to create glint(s) on the eye. Detected glints on the original image are used to convert the relative unwrapped phase map to an absolute unwrapped phase map.

Abstract: Distributing content between media devices is disclosed. An item stored on a first media device is selected for distribution. A distribution type associated with the item is specified, where the distribution type is indicative of a compensation arrangement. A copy of the item is transferred to a second media device.