Adhawk Microsystems Inc.

Fan Yang

Niladri Sarkar

Nino Zahirovic

Brendan Redmond O'Hanlon

Duncan Wesley Strathearn

Mahdi Olfat

Mohammad Mohsenzadeh

Arash Rohani

Brendan Redmond O′Hanlon

Kenneth Mccoubrey

Kenneth McCoubrey

Systems and methods for monitoring the instantaneous position of a scanning element of a light scanner via an optical-feedback signal are disclosed, where the optical-feedback signal is a portion of a light signal being steered in a two-dimensional pattern by the light scanner. The optical-feedback signal is detected by a position monitor that provides a commensurate feedback signal. In some embodiments, the feedback signal is used to develop a transfer function for the light scanner via a calibration routine. In some embodiments, the feedback signal is used in a closed-loop driving scheme used to drive the light scanner. Embodiments in accordance with the present disclosure are particularly well suited for use in object tracking systems, such as eye trackers.

Light scanner having closed-loop control based on optical feedback

Systems and methods for determining the resonant frequencies of at least one axis of a two-axis resonant light scanner based on a measured resistance of at least a portion of one of the axes are disclosed. Precise knowledge of the resonant frequencies of each axis enables quasi-closed-loop operation of a light scanner, wherein the resonant frequencies of its axes can be periodically updated to ensure the proper drive frequencies are used. Furthermore, by determining the relationship between the measured resistance and scanner angle, calibration of the scanner is facilitated and even enabled at the wafer level during fabrication. In some cases, it also enables real-time monitoring of scanner position. Scanners in accordance with the present disclosure are suitable for use in any application that requires one or more reflective elements that can be scanned or steered in at least one dimension.

Resonant light scanner having drive-frequency control based on an electrical parameter

Aspects of the present disclosure describe systems, methods, and structures that provide eye-tracking by 1) steering a beam of light through the effect of a microelectromechanical system (MEMS) onto a surface of the eye and 2) detecting light reflected from features of the eye including corneal surface, pupil, iris&#x2014;among others. Positional/geometric/feature/structural information pertaining to the eye is determined from timing information associated with the reflected light.

Methods and systems for forming images of eye features using a non-imaging, scanning-MEMS-based eye-tracking system

Timer-based eye-tracking

The present disclosure describes systems and methods that enable eye-tracking by steering a light signal in a high-density Lissajous pattern over a region of an eye and detecting light reflected from the eye using a non-imaging photodetector configuration. The light signal is scanned by driving each axis of a two-axis MEMS scanner with a periodic signal having a frequency that is based on the resonant frequency of that axis. By choosing periodic signals having frequencies that give rise to precession of the Lissajous pattern at a high rate, a high-density scan pattern is quickly generated, thereby enabling eye tracking with high spatial resolution and low latency.

Eye-tracker with improved beam scanning and method therefor

Aspects of the present disclosure describe an improved calibration method for systems, methods, and structures that provide eye-tracking by 1) steering a beam of light through the effect of a microelectromechanical system (MEMS) onto a surface of the eye and 2) detecting light reflected from features of the eye including corneal surface, pupil, iris&#x2014;among others. Positional/geometric/feature/structural information pertaining to the eye is determined from timing information associated with the reflected light.

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London, Canada

Fan Yang