A system intended to be worn by a user and containing a display device, said system comprising: - a helmet; - a mechanical arch securely mounted on the front part of said helmet, said arch containing: ∘ a display device containing a combiner; ∘ an optical position-detection device; ∘ a binocular attachment assembly; ∘ a movable visor; - detachable binoculars containing an attachment holder for attachment to said mechanical arch; the movable visor containing two axes of rotation located symmetrically on either side of the mechanical arch and at the height of the user's forehead, said visor having two main positions which are as follows: - a lower use position, applied when the binoculars are not mounted in their holder, the visor covering the combiner and leaving the optical position-detection device uncovered in this lower position; - an upper use position, applied when the binoculars are mounted in their holder, the visor being located on the top of the helmet and leaving the optical position-detection device uncovered in this upper position. said mechanical arch being mounted on said helmet by means of two attachment assemblies located symmetrically on either side of the helmet, each attachment assembly having a spacer, the thickness of which is matched to the size of the helmet such that the mechanical arch is of one size, independently of the helmet. - a helmet; - a mechanical arch securely mounted on the front part of said helmet, said arch containing: ∘ a display device containing a combiner; ∘ an optical position-detection device; ∘ a binocular attachment assembly; ∘ a movable visor; ∘ a display device containing a combiner; ∘ an optical position-detection device; ∘ a binocular attachment assembly; ∘ a movable visor; - detachable binoculars containing an attachment holder for attachment to said mechanical arch; the movable visor containing two axes of rotation located symmetrically on either side of the mechanical arch and at the height of the user's forehead, said visor having two main positions which are as follows: - a lower use position, applied when the binoculars are not mounted in their holder, the visor covering the combiner and leaving the optical position-detection device uncovered in this lower position; - an upper use position, applied when the binoculars are mounted in their holder, the visor being located on the top of the helmet and leaving the optical position-detection device uncovered in this upper position. - a lower use position, applied when the binoculars are not mounted in their holder, the visor covering the combiner and leaving the optical position-detection device uncovered in this lower position; - an upper use position, applied when the binoculars are mounted in their holder, the visor being located on the top of the helmet and leaving the optical position-detection device uncovered in this upper position. said mechanical arch being mounted on said helmet by means of two attachment assemblies located symmetrically on either side of the helmet, each attachment assembly having a spacer, the thickness of which is matched to the size of the helmet such that the mechanical arch is of one size, independently of the helmet.