ENHANCED EYE TRACKING FOR AUGMENTED OR VIRTUAL REALITY DISPLAY SYSTEMS

Described herein are methods and display systems for enhanced eye tracking for display systems, such as augmented or virtual reality display systems. The display systems may include: a light source configured to output light and a moveable diffractive grating configured to reflect light from the light source, the reflected light forming a light pattern on the eye of the user; a plurality of light detectors to detect light reflected from the eye; and one or more processors. The display system changes the orientation of the diffractive grating, such that the light pattern reflected from the diffractive grating is scanned along an axis across the eye. Light intensity patterns are obtained via the light detectors, with a light intensity pattern representing a light detector signal obtained by detecting light reflected off of the eye as the light pattern is scanned across the eye. Due to differences in how light reflects off of different parts of the eye, different eye poses provide different light intensity patterns and the eye pose is determined based on detected light intensity pattern.