Patent ID: 8657442

Claim:
A pair of ophthalmic spectacles, comprising: two lenses; a frame configured to hold and respectively position the two lenses in front of corresponding eyes of a wearer of said spectacles, and allow separate vision for the wearer through each lens, said pair of spectacles including for each lens: at least one radiation source configured to produce radiation to be reflected by the sclera and by the iris of the corresponding eye of the wearer in accordance with differing reflection intensity coefficients respectively for the sclera and the iris; at least one detector configured to measure respective intensities of portions of the radiation produced by the source, reflected respectively in ocular areas of a border between the sclera and the iris of the corresponding eye that move about during eye movements; and at least four radiation output or input sections arranged in the lens, each output section being arranged to direct a portion of the radiation produced by the source towards at least one of said ocular areas, and each input section being arranged to collect a portion of the radiation reflected by one of said ocular areas, so as to form at least two radiation paths which each comprise a reflection on the corresponding eye, in one of the ocular areas in which the portions of the border between the sclera and the iris of said eye move about; a means for separating the portions of radiation transmitted between said at least one radiation source and said at least one detector by different respective radiation paths; and a computation unit configured to characterize a direction of gaze of the wearer towards an observation point, as a function of the intensities which are simultaneously measured for the two lenses, wherein said pair of spectacles comprise as many radiation output sections as radiation input sections for each lens, each of said output sections being adjacent in the lens to one of said input sections to form a separate radiation emission-reception pair corresponding to one of said radiation paths, each emission-reception pair being arranged in front of one of the ocular areas in which one of the portions of the border between the sclera and the iris of the corresponding eye moves about during eye movements.