US Patent 9952428 Heads-up display comprising an optical mixer with controllable pupil expansion

The general field of the invention is that of heads-up display systems comprising at least one display and one optical guide comprising a first image guide comprising a plurality of first internal semi-reflecting plates, inclined with respect to a first plane. The heads-up display system according to the invention comprises:an oculometer designed to detect the position of the pupil of the eye of an observer;at least one of the said first plates comprising a processing with programmable reflectivity, the said reflectivity depending on the position and/or of the orientation of the ocular pupil detected by the oculometer, in such a manner as to reflect the image of the display towards the said pupa and only towards the latter.