Optical device for a head-mounted display, and head-mounted device incorporating it for augmented reality

Abstract

The present invention relates to an optical device usable in a head-mounted display which comprises a light conducting element and at least one wafer, and to a head-mounted device which is configured to provide an informative display of augmented reality for a wearer of the head-mounted device and which comprises such an optical device. This optical device () comprises: a light conducting element () which has two first and second opposite main faces (and) and which inputs and conducts by total internal reflections a light () received from the light source () and partially outputs it out of said element, at least one wafer () which comprises an internal surface () facing a said first main face of said light conducting element, and interposition means in contact with said first main face and said internal surface and defining a gap () optically isolating said element. According to the invention, said interposition means comprise a peripheral sealing arrangement () which extends along its peripheral length between and in sealing contact with a peripheral area () of said internal surface and a facing zone () of said first main face, at least one portion of said sealing arrangement exhibiting a locally reduced optical coupling with said first main face to preserve said internal reflections at said at least one portion toward the inside of said element.