Abstract: A stamper suppressed in surface roughness, uneven thickness, and deviation of circularity in inner circumference, a method of producing the same, an optical recording medium produced by molding using the stamper, and a method of producing the same, wherein a base member having a mirror polished main surface and comprising silicon or glass is formed with a resist film; the resist film is exposed and developed so as to form a resist film of a pattern corresponding to relief shapes; the mirror surface of the base member is processed to relief shapes (projecting regions and recessed regions) by dry etching etc. using the obtained resist film as a mask so as to obtain a stamper; the obtained stamper is used for injection molding to form a medium substrate; and an optical recording multilayer film and a protective layer are formed to thereby produce an optical recording medium.

Abstract: A digital optical information disk contains content and/or non-content information on both sides of a single substrate produced by a process that embosses the surfaces of both sides substantially simultaneously. Simultaneous molding substantially eliminates the need for lamination when two or more data layers are to be provided. Preferably, the disk is relatively small, such as less than 50 mm in diameter and can replicate marks or features with a z-dimension magnitude of about 80 mm or more. The disk remains within a specified opto-mechanical range of an optical transducer and has little, if any, non-planarity (warp) or other distortion. The disk can be used for reading pre-written or mastered content, e.g., in a user's device, and/or can include information or features that permits or supports utility functions, allowing the user to record data thereon such as tracking, sector, location, timing, synchronization features or combinations thereof.

Abstract: A molded lens used in an optical pickup device provided with a plane of incidence having a first optical surface and a plane of emergence having a second optical surface, and a form of an outer circumference of the molded lens is formed by a first straight line portion which is in parallel substantially with a plane including an optical axis, a second straight line portion which is in parallel with the first straight line portion and is symmetric with the first straight line portion about the plane and by two circular arcs each connecting end portions of the first and second straight line portions. A part of a fringe of each of the first and second optical surfaces is substantially in a form of a circle whose center is on the optical axis is cut off by each of the first and second straight line portions.

Abstract: The invention provides a method of shaping optical storage devices (OSD) by placing an OSD between a die set having a male die and female die corresponding to a desired shape and advancing and retracting the die set so as to die-cut the OSD to the desired shape to form a shaped OSD, the shaped OSD products formed therefrom and the die set.

Abstract: An apparatus and method for aligning a disk with an imprinting surface are described. In one embodiment, the apparatus has a die which includes an air-bearing mandrel having a tapered nose to engage an ID of the disk, a circular imprinting surface having a centerline concentric with the air-bearing mandrel, and an air-bearing cavity to position the disk. The axial movement of the top die towards the bottom die guides the ID of the disk into coincident alignment with the centerline of the top die.

Abstract: Disclosed is a method of manufacturing optical information storage media and multi-layered optical information storage media. Paired information storage structures have characteristic wavelength and polarization states, and from which recorded information can be read by a laser beam having similar wavelength and polarization-state characteristics.

Abstract: To improve the quality of transfer signal by reducing loss of azimuth when the magnetic transfer is performed by bringing a master carrier and a slave medium into close contact with each other and applying transfer magnetic field thereto, even if the width of track is narrowed. The master carrier 3 has a pattern which corresponds to a transfer information for high density recording and is formed of a soft magnetic layer 32 with a width W of track of 3 ?m or less, wherein the pattern is written and formed by scanning with an electron beam EB of which a writing diameter d is smaller than the width W of track, on a same track over plural times. Writing is performed approximately to a rectangular shape, whereby the loss of azimuth can be reduced and the accuracy of transfer can be enhanced.

Abstract: A method of making composite discs continuously, including forming for each disc a first, a second layer, and a third support layer, each support layer being disc shaped and having a first surface with information indicia. An information layer is added to each support layers respectively. The said first and third support layers are positioned in a facing relationship, with the first and third information layers being adjacent. The third support layer is then separated from the third information layer, which thus remains attached to the first support layer. The first and second support layers are then joined. These steps are performed on a manufacturing line with conveyor belts transferring the support layers from station to station.

Abstract: A data storage master disk and method of making a data storage master disk. The data storage disk master is for use in a data storage disk replication process. The data storage disk molding processes produces replica disks having a surface relief pattern with replica lands and replica grooves. The method includes providing a master substrate. The master substrate is at least partially covered with a layer of photosensitive material. A surface relief pattern having master lands and master grooves is recorded in the data storage disk master, including the steps of exposing and developing the photosensitive material. The exposing and developing of a specified thickness of photosensitive material is controlled to form master grooves extending down to a substrate interface between the master substrate and the layer of photosensitive material, such that the width of the master grooves at the substrate interface corresponds to a desired width of the replica lands.

Abstract: Two substrates are simultaneously produced by an injection molding apparatus, and the injection-molded substrates are alternately arranged and cooled by a cooling apparatus. The cooling apparatus has a feed screw mechanism for feeding the alternately arranged substrates in one direction while cooling air is being applied to the substrates. An information recording medium which includes a substrate is manufactured on a production line having a single injection molding apparatus for simultaneously injection-molding two substrates and four dye solution coating machines for forming a dye recording layer for recording information on each of the substrates.

Abstract: The present invention is a method and system of marking data media products by introducing a predetermined tracing substance constituting a security marking into a polycarbonate (or polystyrene) composition during the manufacturing stages of the polycarbonate material into a data media, such as a compact disc (CD) or digital versatile disc (DVD). This marking technique is useful in tracking pirated data and/or sources, such as CDs or DVDs, to thereby prevent future pirating of data. Using mass spectrometry, specific types and/or quantities of isotopes of each tracing substance, on a structural level, are used to indicate a specific marking and product identity characteristics, such as a specific lot number, batch number, manufacturer identity, shipping date and the like. The security marking is preferably invisible to the naked eye. The security marking technique is also useful for tracking, authenticating and quality control purposes.

Abstract: The invention relates to a matrix suitable for use in the replication of a plastic element having a positive microstructure, comprising a first wear-resistant layer that is supported by a carrier element, wherein the matrix comprises a heating means for supplying electrical heat energy through the wear-resistant layer or carrier element. The invention further relates to a plastic element producing machine and a method for the manufacture of a plastic element having a surface with a positive microstructure.

Abstract: An optical disk molding apparatus and method are provided which prevent data formed on a molded object from being damaged and prevent quality deterioration of the molded object. There are provided a mold moving device, a first gas supply device, and a controller, whereby a first release space part is formed by opening molds from a mold clamp state by a movement distance not damaging a data transferred face of the optical disk, and a gas is supplied to the first release space part at a point in time when the first release space part is formed, thereby totally separating the optical disk and a stamper from each other. No damage is caused to a data transferred face at the point in time when the first release space part is formed. Since separation between the optical disk and the stamper is performed via pressure of the gas after the first release space part is formed, data is prevented from being damaged over the data transferred face of the optical disk in its entirety.

Abstract: An apparatus for the automated profiling the edge of successive optical disks, and including an optical disk supply assembly for holding a supply of optical disks to be profiled, a turntable for receiving an optical disk to be profiled, and for reciprocating between an optical disk loading position and an optical disk profiling position. A clamping assembly is provided for clamping the optical disk in a stationary condition to the turntable during movement between the loading position and the profiling position. A profiling cutter profiles the edge of the optical disk into a predefined shape when the turntable is in the profiling position.

Abstract: A multilayer optical recording medium includes a substrate that has grooves for tracking purposes formed on a surface thereof on an incident side for a laser beam, the guide grooves having a recording layer formed on a surface thereof, and a spacer layer that has grooves for tracking purposes formed on a surface thereof, the guide grooves having another recording layer formed on a surface thereof and the spacer layer being formed above the substrate. The respective guide grooves are formed deeper the closer the grooves are positioned to the substrate. By doing so, it is possible to maintain a high signal level for a tracking error signal during a tracking servo for the recording layer that is susceptible to the effects of the thickness distribution of the spacer layer. Accordingly, it is possible to favorably perform the recording and reading of data on the recording layer in the same way as the recording and reading of data on the recording layer.

Abstract: A description is given of a method of manufacturing a stamper for use in the manufacture of Small Form Factor (SFF) optical data storage media. A conventional master plate (2) is provided with a series of areas with spiral- or concentric-shaped information tracks (3a-3h), having a relief structure, with the center of each area (3a-3h) being located outside the axis of rotation (9) of the master plate (2). This is done by using a conventional master recorder and a separate master plate support structure (1) without the necessity for complex movements of the master recorder writing head. The master plate (2) thus obtained is used to produce the stamper, containing a negative replica of the surface of the master plate (2).

Abstract: There is provided a process of producing a laminate type optical disk comprising the steps of: (1) molding a pair of substrates of a transparent resin at least one of which substrates has irregularities on its one main surface; (2) forming a metal thin film on said one main surface having the irregularities, and then (3) laminating the pair of the substrates while the metal thin film is located inside and bonding the substrates by means of an adhesive which is supplied between the substrates, the process being characterized in that after the step (1), a waiting treatment is carried out in which the molded substrates are cooled to such a temperature that a difference between said temperature and a temperature of an atmosphere surrounding the substrates is not greater than 5° C. while keeping a moisture (or water) content of the substrates not larger than 0.1% by weight, and then the step (2) is carried out.

Abstract: Without forming a center hole, a light-transmitting resin layer is deposited and formed on a disc-shaped substrate material. A method for fabricating an optical disc includes the steps of injecting a synthetic resin from a gate into the cavity of a mold assembly 30 to mold and cure a disc-shaped substrate material 12 in conjunction with a sprue runner 14 in the gate; depositing a film 18 on the disc-shaped substrate material 12 integrated with the sprue runner 14 taken out of the mold assembly 30; forming a light-transmitting resin layer 22; and forming a center hole 28 by punching through a center portion 26 of the disc-shaped substrate material 12 in conjunction with the sprue runner 14.

Abstract: An optical disk includes a first substrate having a surface which is formed to have pits representing information, and on which a reflection film is formed, and a second substrate which is light-transmissive and has a surface formed to have pits representing information, and on which a translucent film is formed of silver or sliver alloy containing silver as a main ingredient. The reflection film and the translucent film are located opposite to each other, and an intermediate layer is light-transmissive fills a gap between the reflection film and the translucent film.

Abstract: Two substrates are simultaneously produced by an injection molding apparatus, and the injection-molded substrates are alternately arranged and cooled by a cooling apparatus. The cooling apparatus has a feed screw mechanism for feeding the alternately arranged substrates in one direction while cooling air is being applied to the substrates. An information recording medium which includes a substrate is manufactured on a production line having a single injection molding apparatus for simultaneously injection-molding two substrates and four dye solution coating machines for forming a dye recording layer for recording information on each of the substrates.

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: Disclosed is a method for producing an information-recording medium comprising, on a substrate, a dye recording layer capable of recording information, the method comprising the step of drying the substrate formed with the dye recording layer by allowing clean air to flow while rotating the substrate at a high speed; wherein an intake for introducing the clean air is narrowed by arranging a lid having a circular opening at a central portion, at an opening disposed at an upper portion of an apparatus for rotating the substrate at the high speed.

Abstract: In one embodiment, the method for producing a stamper, comprises: forming a nickel plated substrate having desired surface features on one side; disposing a managed heat transfer layer on a second side of said substrate; forming a thickness of said managed heat transfer layer having a variation of less than about 5%; and altering said exposed surface of said managed heat transfer layer. Also disclosed are a method and apparatus for producing data storage media.

Abstract: The invention relates to methods for making mold tools. More particularly, the mold tools are used for molding a resin substrate which has fine pits, i.e., concavities and protuberances. The invention also pertains to a method for manufacturing a resin substrate. Such resin substrates may be used as an optical disk, a magnetic disk, a hard disk, etc., for recording data. According to a preferred embodiment of the invention, a first metallic (Ni) mold tool (father) is made which is a duplicate of a master substrate, then a resin mold tool (mother) is made which is a duplicate of the first metallic mold tool and finally a second metallic (Ni) mold tool (son) is made which is a duplicate of the resin mold tool. Both the father and son may be referred to a “stamper”. The invention also relates to methods of manufacturing a mold tool for molding the base of an optical disk having at least one signal recording region and at least one non-signal recording region.

Abstract: A method of performing imprint lithography of a surface of a workpiece including a substrate, wherein a stamper/imprinter comprised of a material having thermal expansion characteristics different from the material of said substrate is utilized for embossing a desired pattern in said workpiece surface, the method comprising conducting the embossing at room temperature in order to avoid deleterious effects arising from differences in thermal expansion/contraction characteristics between the stamper/imprinter and the workpiece which occur during conventional imprinting at elevated temperatures. Embodiments of the invention include forming servo patterns in disk-shaped substrates utilized in the manufacture of hard disk magnetic recording media.

Abstract: A production process of an optical disk, wherein when a layer of an ultra violet rays curing resin which constitutes a portion of the optical disk is formed, a comi-transparent film of a metal is formed an a molded substrate on which a pattern was transcribed and this molded substrate is used as a semi-transparent stamper, and the production of an optical disk with two layers at one side is made easy thereby.

Abstract: In one embodiment, the method for producing a stamper, comprises: forming a nickel plated substrate having desired surface features on one side; disposing a managed heat transfer layer on a second side of said substrate; forming a thickness of said managed heat transfer layer having a variation of less than about 5%; and altering said exposed surface of said managed heat transfer layer. Also disclosed are a method and apparatus for producing data storage media.

Abstract: An optical recording medium capable of improving uniformity of thickness of a protective film and suppressing warping. The medium is configured to comprise a substrate, an optical recording film formed on the substrate, and a light transmitting protective film formed above the optical recording layer, wherein the protective film comprises a polymer sheet produced by melt casting and an adhesive layer for bonding the polymer sheet to the optical recording layer. As the polymer sheet, a polycarbonate sheet, a cyclic polyolefin sheet, etc. can be used. As the adhesive layer, an ultraviolet curing resin, a heat curing resin, an epoxy resin-based adhesive agent or a pressure-sensitive tackiness agent-may be used alone or mixed or stacked.

Abstract: Recording/reproducing information signals to/from a recording medium appropriately even though the clearance from the signal recording surface of the recording medium to an optical head slider becomes significantly small. An optical head slider 10 includes a sliding member 11 which is floated and slides on a recording medium 4 at the time of recording/reproducing signals to/from the recording medium 4, a hemispheric objective lens 12 which is bonded to the sliding member 11, and a magnetic field generating means 16, which is mounted to the bottom of the sliding member 11 which faces the recording medium 4. The sliding member 11 is made of the same material as that of the optical lens 12, and a flat surface of the optical lens 12 is bonded to the top surface of the sliding member 11.

Abstract: Disclosed is a method for producing an information-recording medium comprising, on a substrate, a dye recording layer capable of recording information, the method comprising the step of drying the substrate formed with the dye recording layer by allowing clean air to flow while rotating the substrate at a high speed; wherein an intake for introducing the clean air is narrowed by arranging a lid having a circular opening at a central portion, at an opening disposed at an upper portion of an apparatus for rotating the substrate at the high speed.

Abstract: A method and system for providing copy-protected optical medium using transient optical state change security materials capable of changing optical state when exposed to a wavelength of about 630 nm to about 660 nm and software code to detect such change in optical state.

Abstract: Various methods and apparatus for simultaneously texturing two single-sided hard memory disks is provided. The two disks are placed in a concentric contact merge orientation such that the outwardly facing surface of each disk may be simultaneously subjected to texturing by equipment designed to texture one double-sided disk.

Abstract: An injection-compression molding apparatus includes a stationary mold provided with a nozzle for injecting molten resin, and a movable mold driven by a servo motor. In compressing the resin, high-speed position control of the movable mold is first performed, which is then switched to speed feedback control which enables delicate regulation of clamping pressure in accordance with pressure fluctuations in the resin.

Abstract: There is provided an intermediate for an optical recording medium, which can be uniformly coated with resin by the spin coating method without using a resin coating-assisting member, and allows formation of a central mounting hole without burrs. The intermediate comprises a hollow cylindrical protruding portion protruding from one surface on which functional layers are formed and a circular recess formed in a central portion of the other surface and having a diameter equal to that of the central mounting hole, and a temporary central hole formed to extend through a central portion of the recess and having a diameter smaller than that of the recess. The protruding portion has an outer diameter smaller than the diameter of the mounting hole and an inner diameter not smaller than the diameter of the temporary central hole, and has a central axis thereof substantially aligned with a center of the temporary central hole.

Abstract: A light-transmitting electromagnetic wave-shielding material includes a hydrophilic transparent resin layer laminated on a transparent substrate. An electroless plating layer is laminated on the hydrophilic transparent resin layer in a pattern, and a black pattern section is formed on the hydrophilic transparent resin layer under the electroless plating layer. Therefore, a black electroplating layer is formed to cover the electroless plating layer laminated in a pattern.

Abstract: A recording medium for information signals including a substrate, a signal recording layer provided on one major surface of the substrate and a clamp member having a positioning unit at its center portion and formed of a material that can be magnetically attracted by a magnet. The clamp member is unified to the center portion of the substrate so that the surface of the clamp member will be flush with the substrate surface.

Abstract: An optical disk, which comprises: a common integral substrate having grooves and/or pits formed on its both sides: and a film structure on at least one side of the integral substrate. They are manufactured by preparing two stampers; simultaneously forming grooves and pits on both sides of an integral substrate by use of said two stampers mounted on a respective fixed mold and moving mold; and forming the film structure on at least one side of said integral substrate by depositing material from targets suspended to both sides of said integral substrate. The disks are superior in mechanical properties and reliability. As for reliability, the present optical disk is prepared without using a bonding process, which overcomes the problem of adhesive out-flow.

Abstract: The present invention is to provide a production method for an optical disc, capable of obtaining a good S/N ratio without deterioration of the stamper quality due to reaction with an electron attractive group contained in a resist material. The processes of forming a resist film on a substrate, patterning the resist film on the substrate by an electron beam cutting, forming a nickel alloy thin film on the patterned resist film, forming a nickel layer on the nickel alloy thin film by the electrocasting, and injection molding of a resin, using the nickel layer peeled off from the nickel alloy thin film as a stamper, are provided. The nickel alloy thin film has a composition containing Ni element as the main component as well as Ru element by less than 25% by weight.

Abstract: A liquid-form adhesive, which is a raw material of the cover layer, is supplied to a plate surface of the disc substrate, which has been set on a turntable, after which a dummy substrate is set on the disc substrate. The dummy substrate is positioned to be concentric with the disc substrate. A setting surface of the dummy substrate is disposed to face the plate surface. In this state, the disc substrate is rotated together with the dummy substrate by rotation of the turntable, and the adhesive is spread to an outer peripheral side of the disc substrate by centrifugal force. Thus, the adhesive fills a space between the plate surface and the setting surface, and is spin-coated on the plate surface. Irregularities in thickness of the applied adhesive are suppressed by the setting surface of the dummy substrate.

Abstract: An optical disk and a method of producing it, particularly a stamper for molding a semiconductor disk base capable of forming an optical disk sufficiently compatible with commercially available CD (Compact Disk) players, a method of producing a stamper, a method of producing an optical disk base, a method of producing an optical disk, and an optical disk base and optical disk are disclosed. The present invention improves both of transferability and tact of an optical disk base molding cycle, allows a fine pattern to be formed in a transfer surface, and makes it needless to change existing molding equipment. In addition, when guide grooves formed in the optical disk are filled with a pigment by spin coating, the guide grooves have a substantially uniform configuration in the radial direction of the disk. The optical disk is sufficiently compatible with various CD players available on the market.

Abstract: This invention provides an optical disk effective in both precision and productivity, and to a process for the manufacture thereof. The optical disk allows reading of the information recorded on each information-recording surface of the two or more information-recording surfaces by varying the focal position of a playback laser beam incident on and passing through said light transmitting substrate; and the optical disk is provided with a transparent layer that is laminated onto the light transmitting substrate and is constituted of a thermoplastic resin sheet of uniform thickness and the transparent layer has an information-recording surface other than the surface of said light transmitting substrate formed thereon.

Abstract: A stamper having a good cost performance, which can be easily separated (released) from a layer of photo-curing resin, is provided. A process for producing an optical multi-layer recording medium having a good productivity is also provided by using such a stamper. The process for producing an optical multi-layer recording medium includes the steps of: laminating a layer of non-cured photo-curing resin and a transparent stamper made of amorphous polyolefin resin in this sequence on a substrate; curing the non-cured photo-curing resin with light permeated through the transparent stamper; and removing the transparent stamper.

Abstract: Two substrates are simultaneously produced by an injection molding apparatus, and the injection-molded substrates are alternately arranged and cooled by a cooling apparatus. The cooling apparatus has a feed screw mechanism for feeding the alternately arranged substrates in one direction while cooling air is being applied to the substrates. An information recording medium which includes a substrate is manufactured on a production line having a single injection molding apparatus for simultaneously injection-molding two substrates and four dye solution coating machines for forming a dye recording layer for recording information on each of the substrates.

Abstract: A transfer layer on a surface of a mold has a thickness distribution along the radius direction that the layer is thick in an inner round portion but is gradually thinner toward an outer round portion. An adhesive layer is formed between a surface of a signal substrate which bears a signal recording film and the mold which seats the transfer layer. The adhesive layer has a thickness distribution that the layer is thin in an inner round portion but is gradually thicker toward an outer round portion. Since the thickness distributions along the radius direction of the transfer layer and the adhesive layer are opposite to each other, the thickness distribution of an isolation layer which comprises the two layers is uniform.

Abstract: An optical data storage/recording medium is provided with a thin film adjacent a data surface. Potential undesired effects of the presence or thickness of the thin film are adjusted for or compensated for to reduce or eliminate the undesired effects. In one aspect, the (uncoated) physical size of data layer features are adjusted so as to produce desired as-detected sizes, shapes or spacings, after a coating or thin film is present. In one aspect, length and/or width of raised features have an uncoated physical size less than the desired as-detected size. In one aspect, depressed features have uncoated physical dimensions greater than desired as-detected dimensions.

Abstract: Preformatted areas in at least the most distal recording layer from an object lens among a plurality of recording layers in an optical disc include guard areas at both ends of the respective recording layer in the tracing direction. No data is recorded on the guard areas. The guard area length GL is determined to satisfy the following formula: GL≧YL+T×(NA/n)/[1−(NA/n)2]1/2 where YL is a maximum allowable value of position deviation between the preformatted areas in the most distal recording layer and in another recording layer in the tracing direction; NA is the numerical aperture of the object lens; T is a distance between the most distal and the another recording layer; and “n” is an refraction index of a medium between the most distal and the another recording layers.

Abstract: The invention relates to a method of manufacturing a master mold (1), which is used to manufacture an optical information disc, such as a CD or DVD. According to the method, a substrate (3) is provided with a photosensitive layer (5), which is subsequently irradiated by means of a radiation beam (7), which is focused to a scanning spot (11) on said layer by means of an optical lens system (9). A liquid, such as water, is supplied into a gap (53) present between the photosensitive layer and an auxiliary lens (59) of the lens system facing said layer. As a result, the size of the scanning spot is decreased and the information density of the information disc to be manufactured is increased. According to the invention, the liquid is supplied via a supply opening (69) which is positioned immediately adjacent the auxiliary lens (59), in a direction which, viewed from the scanning spot (11), is contrary to a direction (Z) wherein the substrate (3) is moved with respect to the lens system (9).

Abstract: In an injection molding apparatus 62 on which a disk molding die is mounted, wherein the disk molding die is comprised of a stationary die 10 and a movable die 20, a plurality of principal parts of which are separately temperature controlled by media, a control device 50 of the injection molding apparatus 62 is provided with a temperature control mechanism for controlling temperatures of the media which are pumped by a plurality of temperature control devices 51a and 51b in order to control the temperatures of said principal parts.

Abstract: A writable optical disc has an information writing track, and a guiding track for introducing a laser beam to the information writing track. The guiding track has prepit information recorded thereon, the prepit information including at least address information of the optical disc. The prepit information is recorded on the guiding track at a position where interference of adjacent guiding tracks with the prepit information is prevented. The information writing track is a groove track, and the guiding track is a land track.

Abstract: The invention relates to block copolymers for optical data storage.