Eye tracking using self-mixing interferometry
AssigneeApple Inc.
InventorsTong Chen, Mark T. Winkler, Edward Vail, Xibin Zhou, Ahmet Fatih Cihan, Walter Nistico
Life of this patent
Estimating the term…
Abstract
An eye tracking device includes a head-mountable frame, an optical sensor subsystem mounted to the head-mountable frame, and a processor. The optical sensor subsystem includes a set of one or more SMI sensors. The processor is configured to operate the optical sensor subsystem to cause the set of one or more SMI sensors to emit a set of one or more beams of light toward an eye of a user; to receive a set of one or more SMI signals from the set of one or more SMI sensors; and to track a movement of the eye using the set of one or more SMI signals.
Claims22
An eye tracking device, comprising:
- a head-mountable frame;
- a camera;
- an optical sensor subsystem mounted to the head-mountable frame and including,
- a set of one or more self-mixing interferometry (SMI) sensors;
- and
- a processor configured to,
- cause the camera to acquire, at a first frequency, a set of images of an eye of a user;
- operate the optical sensor subsystem to cause the set of one or more SMI sensors to emit a set of one or more beams of light toward the eye of a user;
- sample, at a second frequency greater than the first frequency, a set of one or more SMI signals from the set of one or more SMI sensors;
- and
- track a movement of the eye using the set of one or more SMI signals and the set of images of the eye of the user, wherein:
- the set of one or more SMI sensors comprises:
- an array of SMI sensors;
- and
- circuitry configured to address different SMI sensors or different subsets of SMI sensors in the array of SMI sensors;
- and
- the processor is configured to selectively operate the different SMI sensors or the different subsets of SMI sensors using the circuitry.
An eye tracking device, comprising:
- a set of one or more self-mixing interferometry (SMI) sensors;
- a camera;
- and
- a processor configured to,
- cause the camera to acquire, at a first frequency, a set of images of an eye of a user;
- cause the set of one or more SMI sensors to emit a set of one or more beams of light toward the eye of the user;
- sample, at a second frequency greater than the first frequency, a set of one or more SMI signals generated by the set of one or more SMI sensors;
- determine a gaze vector of the eye using at least one image in the set of images;
- and
- track a movement of the eye using the set of one or more SMI signals.
A method of tracking movement of an eye, comprising:
- operating an optical sensor subsystem to cause a set of one or more self-mixing interferometry (SMI) sensors in the optical sensor subsystem to emit a set of one or more beams of light toward the eye of a user comprising at least one of:
- projecting multiple beams of the set of one or more beams simultaneously;
- or
- emitting the multiple beams sequentially;
- or
- scanning at least one beam of the set of one or more beams;
- receiving a set of one or more SMI signals from the set of one or more SMI sensors;
- and
- tracking the movement of the eye using the set of one or more SMI signals, wherein tracking the movement of the eye using the set of one or more SMI signals comprises:
- constructing a Doppler cloud using the set of one or more SMI signals;
- and
- extracting eye position information by matching one or more frames of the Doppler cloud to a differential map.
Dependencies are inferred from the claim text.