Abstract: The invention is directed toward techniques for stamping optical data storage disks. A master is first created to include several distinct information regions etched upon a master surface. The master is then used to create one or more stampers. The stampers include a number of distinct stamper regions in locations corresponding to locations of the distinct information regions on the master. The stamper is then used to create a number of first replica disks that include distinct replicated regions. The distinct replicated regions are removed from the first replica disks to define second disks.

Abstract: In exemplary embodiments, the invention provides one or more processes for making stampers for stamping replica data storage disks. For instance, the invention may provide a process for making a family of stampers from one master. Moreover, the invention may provide a way to systematically adjust the depth of the grooves on a stamper in a particular family of stampers while maintaining groove widths that are substantially the same as those of the master.

Abstract: The invention is directed toward techniques for creating molded substrates for use in various different data storage media. The molded substrates have improved thickness profiles that can improve media quality, and in some cases facilitate higher data storage densities. In many cases, the improved thickness profile is a thickness profile that has improved flatness. Mechanical flatness or optical flatness can be achieved. In particular, optical flatness is desirable for substrates used in holographic data storage media having a sandwiched construction.

Abstract: The invention is directed towards techniques for creating optical data storage disks. In one embodiment, the invention provides a simultaneous two-sided rolling bead process. For example, a method may include positioning a first bead of photopolymer for distribution between a bottom stamper and a substrate, and positioning a second bead of photopolymer for distribution between a top stamper and the substrate. The method may also include passing a roller over the top stamper to distribute the beads of photopolymer, curing the photopolymer, and removing the substrate from the stampers. The simultaneous two-sided rolling bead process can be repeated on the same medium to create a two-sided dual-layer data storage medium or a two-sided multi-layer data storage medium.

Abstract: In exemplary embodiments, the invention provides one or more processes for making stampers for stamping replica data storage disks. For instance, the invention may provide a process for making a family of stampers from one master. Moreover, the invention may provide a way to systematically adjust the depth of the grooves on a stamper in a particular family of stampers while maintaining groove widths that are substantially the same as those of the master.

Abstract: In one embodiment, a data storage medium includes at least three layers. The first layer may be a substrate. The second layer includes a polymer and may exhibit surface variations. And the third layer may substantially conform to the surface variations of the second layer. The surface variations may be used to encode read-only data, servo patterns, or other tracking patterns on a data storage medium at very low cost. The surface variations may be detectable on the surface of the medium because the third layer substantially conforms to the variations. Additional layers may be added to the medium so long as they substantially conform to the surface variations such that the variations are exhibited on the surface of the medium.

Abstract: An optical disk exhibiting no detrimental thickness increase (edge wedge effect) that arises at the outer diameter of an optical disk substrate during an injection molding manufacturing process, and an apparatus and method for making such a disk. The optical disk of the present invention is designed for use with an optical disk player, especially where the data on the optical disk is stored air incident. This optical disk includes a disk substrate made from a molded polymeric material. The disk substrate has a first major surface, a second major surface, and an outer edge. The first major surface of the optical disk includes a data region having an intermediate portion and an outer portion. The outer portion extends to the outer edge of the optical disk. The disk substrate has a thickness defined by the distance between the first major surface and the second major surface. The optical disk also includes an information layer covering the data region.

Abstract: A method of making a stamper for use in a data storage disk molding process. The method includes making a first stamper including the steps of providing a stamper body having an information layer thereon. The information layer is covered with a first metal layer. A second stamper is made from the first stamper, which includes the steps of covering the first metal layer with a second metal layer to form a stamper assembly, wherein the first metal layer and the second metal layer are bonded together. The first metal layer and the second metal layer are removed from the stamper assembly to form the second stamper, wherein removal of the first metal layer and the second metal layer is nondestructive to the information layer. In one application, the first metal layer and the second metal layer are made of nickel.

Abstract: Disclosed is a stamper assembly for forming an optical data storage disk in a disk molding process. The stamper assembly includes a block element having a first major surface, and a stamper member having a first major surface and an opposite, second major surface. The first major surface of the stamper member is adapted to contact a disk molding material for forming an optical data storage disk in a disk molding process. The stamper assembly further includes a medium for securing the stamper member to the block element, such that substantially the entire second major surface of the stamper member is affixed to the first major surface of the block element. This arrangement prevents relative movement between the stamper member and the block element. This substantially reduces stamper member wear and increases the useful production lifetime of the stamper assembly.

Abstract: A method of making a stamper for use in a data storage disk molding process. The method includes making a first stamper including the steps of providing a stamper body having an information layer thereon. The information layer is covered with a first metal layer. A second stamper is made from the first stamper, which includes the steps of covering the first metal layer with a second metal layer to form a stamper assembly, wherein the first metal layer and the second metal layer are bonded together. The first metal layer and the second metal layer are removed from the stamper assembly to form the second stamper, wherein removal of the first metal layer and the second metal layer is nondestructive to the information layer. In one application, the first metal layer and the second metal layer are made of nickel.

Abstract: A method of making a stamper for use in a data storage disk molding process. The method includes making a first stamper including the steps of providing a stamper body having an information layer thereon. The information layer is covered with a first metal layer. A second stamper is made from the first stamper, which includes the steps of covering the first metal layer with a second metal layer to form a stamper assembly, wherein the first metal layer and the second metal layer are bonded together. The first metal layer and the second metal layer are removed from the stamper assembly to form the second stamper, wherein removal of the first metal layer and the second metal layer is nondestructive to the information layer. In one application, the first metal layer and the second metal layer are made of nickel.

Abstract: Coded information bearing elements such as video discs may be produced from multilayered articles. The articles comprise a base having a thermoplastic, radiation curable resin on one surface and an embossable electrically conductive or radiation reflective layer over said resin.

Abstract: Imperfections in the surface of information carrying discs, such as video discs, are avoided by an improved process of manufacture. A bead of photopolymerizable mass is moved between two surfaces, one of which is a patterned surface and the other is a surface to which the photopolymerizable mass will bond upon polymerizing. By moving the liquid mass across the patterned surface, air within the pattern is removed by the leading edge of the bead, reducing imperfections.

Abstract: A coded information structure capable of being decoded electronically comprising a base and a first layer of an electrically conductive or electromagneted radiation reflective layer adhered to said base wherein said layer having coded information in the form of areas of said layer having been vertically displaced and having ruptures or necking or the side of the depression and an insulating or transparent protective layer over said first layer.

Abstract: An information carrying element comprising a substrate having adhered to at least one surface thereof a separate layer having a thickness of 1.0 to 100 microns and a circular or spiral pattern of surface variations provides a particularly useful element when said separate layer comprises an abrasion resistant polymer layer derived from 30 to 100% by weight of an epoxy-terminated silane.