Method for calibrating a head-mounted eye tracking device

A computer program product stored on a non-transitory computer readable medium comprising stored sequences of instructions that are accessible to a processor and which, when executed by the processor, causes the processor to carry out the following:

• acquiring eye data relating to a position of an eye of a wearer using at least one camera arranged on a spectacle frame of a head-mounted eye tracking device while having the wearer of the head-mounted eye tracking device look in a direction of reference;
• associating the eye data acquired during the associating with a gaze direction corresponding to the direction of reference using a processor of the head-mounted eye tracking device;
• recording the associated eye data and the gaze direction in a memory of the head-mounted eye tracking device;
• providing a calibration support comprising at least a visual reference element to the wearer wearing the head-mounted eye tracking device;
• and
• placing the calibration support between at least one eye of the wearer and a visual environment of the wearer in a known position relative to the wearer's eye and to the head-mounted eye tracking device so as to define with the visual reference element the direction of reference,
• wherein the at least one visual reference element is an optical opening in the calibration support, and
• wherein the head-mounted eye tracking device comprises ophthalmic lenses mounted on the spectacle frame of the head-mounted eye tracking device, and the gazing direction corresponding to the direction of reference is determined based on a dioptric function of the ophthalmic lenses wherein, during the placing, the calibration support is placed on at least one surface of at least one of the ophthalmic lenses and the gazing direction corresponding to the visual reference element is determined based on the dioptric function of the ophthalmic lenses.