Abstract: A method for fabricating an optical disk master including fabricating a precursor formed from a substrate including at least one layer of metallic material and having at least one protuberance or indentation guiding track; preparing the precursor by superposing on the substrate at least one layer of a first material and a second material different from the first material; eroding at least a portion of a surface of one of the materials to only allow to subsist one of the materials at a site of the guiding tracks; depositing on the surface a reactive resin; personalizing the precursor by structuring the reactive surface as a function of information specific to the master to locally eliminate the reactive resin; performing etching zones of the second material at a site of unmasked guiding tracks; and eliminating subsisting deposits of resin and the first material outside of the zones where it is covered by the second material.

Abstract: A method for fabricating an optical disk master including fabricating a precursor formed from a substrate including at least one layer of metallic material and having at least one protuberance or indentation guiding track; preparing the precursor by superposing on the substrate at least one layer of a first material and a second material different from the first material; eroding at least a portion of a surface of one of the materials to only allow to subsist one of the materials at a site of the guiding tracks; depositing on the surface a reactive resin; personalizing the precursor by structuring the reactive surface as a function of information specific to the master to locally eliminate the reactive resin; performing etching zones of the second material at a site of unmasked guiding tracks; and eliminating subsisting deposits of resin and the first material outside of the zones where it is covered by the second material.

Abstract: The invention relates to a process and a device for the mastering of an optical disk protected against copying and such an optical disk.

Abstract: The disclosure relates to an optical disk of the type including at least one spiral track on which information marks are written in sectors whose addresses are substantially sequential along the track, wherein said disk includes a copy protection zone (PZ) comprising two parts of equal size each including a series of sectors designated by identical addresses on each of the two parts, the data written in this zone being shared between the sectors of the two parts, each sector of the zone also carrying an identifier (D1, D2) characteristic of the part to which the sector belongs, and specific protection data to enable verification of the presence and constitution of said protection zone (PZ) and to enable use of the data written in this zone, at least part of said specific protection data being recorded on said disk. The invention is notably applicable to anti-piracy protection of CD-ROM and DVD-ROM type disks.

Abstract: An anti-piracy recording disk. The disk includes a main recording track which has interruptions or changes of turn. This gives rise to non-sequential reading and therefore to information which is difficult to access. The copying of such a disk by conventional means is very difficult making it possible to easily detect counterfeits or to render any copy unusable.

Abstract: Information recording disk comprising a main recording track comprising one or more interruptions and/or changes of turn, this giving rise to non-sequential reading and therefore to information which is difficult to access. The copying of such a disk by conventional means becomes very difficult, and this will make it possible on the one hand to detect counterfeits by detecting the information and on the other hand to render any copy unusable.

Abstract: The disclosure relates to an optical disk of the type including at least one spiral track on which information marks are written in sectors whose addresses are substantially sequential along the track, wherein said disk includes a copy protection zone (PZ) comprising two parts of equal size each including a series of sectors designated by identical addresses on each of the two parts, the data written in this zone being shared between the sectors of the two parts, each sector of the zone also carrying an identifier (D1, D2) characteristic of the part to which the sector belongs, and specific protection data to enable verification of the presence and constitution of said protection zone (PZ) and to enable use of the data written in this zone, at least part of said specific protection data being recorded on said disk. The invention is notably applicable to anti-piracy protection of CD-ROM and DVD-ROM type disks.

Abstract: The invention relates to a process for producing a plurality of magnetoresistive sensors on the same substrate. The invention particularly has as its object to facilitate a polishing phase of this process. The process of the invention comprises depositing a layer of a magnetoresistive material on a substrate, and then forming in this layer a plurality of magnetoresistive elements. The process further comprises making, at the site of each sensor and before the depositing the magnetoresistive layer, an inclined surface, in such a way that each magnetoresistive element is formed on this inclined surface and exhibits an edge directed outward from the substrate.

Abstract: A mechanical magnitude sensor integrated on silicon, and a method of manufacture. The sensor comprises a bendably deformable conductive blade (4) whose free end (43) constitutes the first plate of a variable capacitor whose fixed second plate (24) is constituted by a conductive zone formed on the silicon substrate. A JFET type structure is formed in the vicinity of the anchor point (41) of the blade (4) with a gate zone (21) situated beneath the anchor portion (41) and with drain and source zones (22, 23) being provided on either side of the gate zone (21) in order to amplify a signal representative of variations in the position of the flexible blade (4). The sensor may be used as an accelerometer or as a pressure sensor.