The system for tracking one or more of a user's eyes comprises a closed-eye detector, an eye tracker operable to detect an eye orientation using a measured deformation of an eyelid corresponding to the eye that has been detected to be shut and an image renderer operable to render a foveated image for display in response to the detected eye orientation. The deformation of the eyelid may be detected by identifying a pattern 1210 on the user’s eyelid 1200. The pattern may be a structured light pattern projected onto the eyelid or a shadow (1430, fig 14) formed by illuminating the eyelid from an oblique angle. The system may also use the physical limits of eye motion, or the motion of the eye before shutting, to predict a region in which deformation may be detected.
