An optical, device adapted for a wearer includes an emitting system, a first wafer and a gap. The emitting system includes a halt conducting element configured to output a light through an exit face of the light conducting element towards an eye of the wearer. The first wafer includes an internal face facing the light conducting element. The gap is arranged between at least the exit face of the light conducting element and the wafer. The internal face of the wafer includes at least a curved surface facing the exit face and has a curvature greater than 0 D.