Efficient image capturing based on eyelid position

A method comprising:

• capturing images of an eye by an inward-facing head-mounted camera;
• emitting, by a head-mounted device, electromagnetic waves towards the eye, and taking measurements of reflections of the electromagnetic waves from the eye;
• wherein average rate of taking measurements of the reflections is higher than average rate of capturing the images;
• detecting, based on the measurements of the reflections, a position of at least one of the eyelids covering the eye (eyelid position);
• and
• operating the inward-facing head-mounted camera according to the eyelid position in a manner that decreases, in the captured images, areas depicting the at least one of the eyelids.

A non-transitory computer readable medium storing one or more computer programs configured to cause a processor-based system to execute steps comprising:

• capturing images of an eye by an inward-facing head-mounted camera;
• emitting, by a head-mounted device, electromagnetic waves towards the eye, and taking measurements of reflections of the electromagnetic waves from the eye;
• wherein average rate of taking measurements of the reflections is higher than average rate of capturing the images;
• detecting, based on the measurements of the reflections, a position of at least one of the eyelids covering the eye (eyelid position);
• and
• operating the inward-facing head-mounted camera according to the eyelid position in a manner that decreases, in the captured images, areas depicting the at least one of the eyelids.