Abstract: The visor can be readily mounted on a helmet by virtue of the fact that it dispenses with the need for any optical relay system. Provision is made for a light image generator, an optical combining and collimating assembly in which a holographic flat plate and a holographic spherical plate are grouped together so as to provide a view of the collimated image superimposed on the landscape. The holographic spherical plate is employed off the axis and produces collimation in a pupil zone placed substantially at the focal distance of the apex of the spherical mirror. The hologram of the spherical plate is recorded by means of a digital hologram in order to minimize aberrations. The flat plate can be fairly steeply inclined with respect to the sighting axis and so designed as to reduce the ratio of parasitic reflection of the imaging channel.

Abstract: A display device with wide field and high optical efficiency is provided including an optical assembly having a spherical holographic mirror used on the axis and a semitransparent mirror. A generator of light images emits a radiation which strikes first of all the convex phase of the spherical mirror, passes through it, and is then reflected by the semitransparent mirror in the direction of the spherical mirror, which reflects it and finally sends it towards the observer. This optical collimation and combination assembly is included in a transparent medium formed by a glass plate with parallel faces and forming a stigmatic optical system at infinity, required for the correct reception of the radiation coming from the outside landscape.