Abstract: The present invention relates to a high-density optical data storage structure. The structure comprising a substrate provided with physical marks, said physical marks being covered by at least one active layer, the physical state of the active layer being modified when irradiated by a laser beam, the substrate consisting of adjacent tracks that are alternately recessed and protruding, the physical marks consisting of pits in the land tracks and of bumps in the groove tracks. The invention is applicable, notably, to the production of high storage capacity optical disks and more particularly to the production of prerecorded optical disks.

Abstract: A cornice for a construction work having an upright surface has a plurality of similar elongated panels of like section and predetermined length. These panels are laterally concave and each have a pair of parallel longitudinal edges and opposite longitudinal ends. A plurality of respective mounts each generally complementary to the concave section of the panels are anchored on the surface spaced apart by a distance equal to the length of the panels. Interengaging formations on the mounts and on the edges of the panels allow the panel edges to be hooked to the mounts. A tensioning device secures the respective panel snugly to the respective mount. Each mount comprises an outer mount member of a convex shape complementary to the concave section of the panels and an inner bracket fixed on the outer member. The anchoring device is secured to the inner bracket.