A system for eye gesture tracking comprising: a machine including a display (130, 310, 380, 410), the display including a plurality of tunable optical elements (300, 330, 385, 430), a device (360, 460, 534, 547) including circuitry configured to: obtain (610, 710) an electrical signal that represents a measurement, by a photodetector, of an optical signal reflected from an eye (120, 320, 420, 510), determine (620, 720) a depth map of the eye based on phase differences between a reference signal and the electrical signal generated by the photodetector, and determine (630, 730) gaze information that represents a gaze of the eye based on the depth map; and one or more processors in communication with the machine and the device, the one or more processors including one or more storage devices storing instructions that are operable, when executed by the one or more processors, to cause the one or more processors to perform the operations including: receiving, from the device, output data representing the gaze information; and determining gaze information representing the gaze of the eye in relation to the display of the machine, characterized in that: the plurality of tunable optical elements include tunable lenses, tunable mirrors, or tunable gratings; wherein the tunable optical elements adjust angles of eye-incident light by refocusing light pathing therethrough based on the determined gaze information as input data. a machine including a display (130, 310, 380, 410), the display including a plurality of tunable optical elements (300, 330, 385, 430), a device (360, 460, 534, 547) including circuitry configured to: obtain (610, 710) an electrical signal that represents a measurement, by a photodetector, of an optical signal reflected from an eye (120, 320, 420, 510), determine (620, 720) a depth map of the eye based on phase differences between a reference signal and the electrical signal generated by the photodetector, and determine (630, 730) gaze information that represents a gaze of the eye based on the depth map; and obtain (610, 710) an electrical signal that represents a measurement, by a photodetector, of an optical signal reflected from an eye (120, 320, 420, 510), determine (620, 720) a depth map of the eye based on phase differences between a reference signal and the electrical signal generated by the photodetector, and determine (630, 730) gaze information that represents a gaze of the eye based on the depth map; and one or more processors in communication with the machine and the device, the one or more processors including one or more storage devices storing instructions that are operable, when executed by the one or more processors, to cause the one or more processors to perform the operations including: receiving, from the device, output data representing the gaze information; and determining gaze information representing the gaze of the eye in relation to the display of the machine, receiving, from the device, output data representing the gaze information; and determining gaze information representing the gaze of the eye in relation to the display of the machine, characterized in that: the plurality of tunable optical elements include tunable lenses, tunable mirrors, or tunable gratings; wherein the tunable optical elements adjust angles of eye-incident light by refocusing light pathing therethrough based on the determined gaze information as input data. the plurality of tunable optical elements include tunable lenses, tunable mirrors, or tunable gratings; wherein the tunable optical elements adjust angles of eye-incident light by refocusing light pathing therethrough based on the determined gaze information as input data.