Abstract: There is provided an optical recording medium, in which a light transmitting layer is formed on a disc substrate, having less deflection and being excellent in recording/reproducing properties. In an optical disc, an information signal area on which an information signal can be recorded and/or reproduced is formed on a major surface of a disc substrate thereof; a light transmitting layer which can transmit a laser beam used in a process for recording and/or reproducing the information signal is formed on a side on which the information signal area is present; and a clamp reference plane is arranged on a major surface of the light transmitting layer in a clamp region.

Abstract: The phase-change type optical information recording medium includes a transparent substrate, a first protective layer on the substrate, a recording layer on the first protective layer, a second protective layer on the recording layer, and a reflective layer on the second protective layer. Assuming that minimum recording linear velocity is V1 and maximum recording linear velocity is V2, then a value of ratio I(V2)/I(V1) of a degree of modulation corresponding to the maximum and minimum linear velocities is between 1 and 1.2.

Abstract: An optical recording medium with a circular body including a substrate, a recording layer and a dielectric layer on the substrate, the circular body having a recording/reproducing area and a hub attached to a surface of the circular body. When the circular body stands vertically, the recording/reproducing area of the hub-attached surface is curved in a convex form, and the flexural amount is from 5 ?m to 100 ?m.

Abstract: An optical information recording medium recordable at a high density two times or more higher than that of currently-used CD-Rs by optimally determining the thicknesses of a recording layer and a reflecting layer. The optical information recording medium comprises the recording layer formed on a transparent substrate having a spiral pregroove formed thereon, wherein a track pitch Tp of the pregroove is 1.0 ?m?Tp?1.2 ?m and a thickness Dg of the recording layer on the pregroove is 80 nm?Dg?120 nm.

Abstract: An optical information recording medium in which the ranges of the refractive index and thickness of a protective layer in a case where the protective layer is constituted by a plurality of layers are newly specified the refractive index and thickness of the protective layer are determined in these ranges, thereby ensuring that even if variation in thickness of the protective layer to ±3 ?m is tolerated, spherical aberration in the optical information recording medium is substantially to within 30 m?rms.

Abstract: An optical recording medium having a plural number of recording layers includes a n-th recording layer (23) (n≧1), made up by a substrate (20) and a semi-reflective layer (21) carried by the substrate (20) and adapted for partially reflecting and partially transmitting the incident light, a (n+1)th recording layer (28), made up by another substrate (25) and a reflecting layer (26) carried by the substrate (25) and adapted for reflecting the incident light, and a light condensing layer (24) for condensing the light incident via the n-th recording layer (23) on the (n+1)th recording layer (28).

Abstract: A data storage product includes a recordable layer having a recordable area and a characteristic width, and a product container having a container volume containing the recordable layer. The data storage product has a storage media volumetric factor defined as the characteristic width of the recordable layer multiplied by the recordable area of the recordable layer divided by the container volume of the product container, wherein the storage media volumetric factor of the data storage product is greater than approximately 450.

Abstract: An optical disk with an embedded security device, or wafer, is presented. The security device includes security features that enable the identification of genuine optical disks versus counterfeit optical disks. Methods for creating optical disks embedded with security devices are also presented. A security device is placed on the center pin of an open mold before the optical disk is formed. Alternatively, an optical disk having a cavity formed on a surface to receive a security device is created. A special mold with a raised platform creates the cavity on the optical disk. As a further alternative, two optical platters, each having a complementary cavity to accommodate a security device are created using a special mold having a raised platform. The security device is inserted into the complementary cavities and the optical platters and security device are bonded together.

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: In reproduction from a magneto-optical recording medium by the domain wall displacement detection method, it is possible to avoid occurrence of ghost signals and to improve dropout, and moreover design of magnetic layers is made easy. A configuration is adopted having at least, in order from the side of incidence of laser light for reproduction, a first magnetic layer 11 constituting a reproduction layer, a second magnetic layer 12 constituting a control layer, a third magnetic layer 13 constituting a blocking layer, and a fourth magnetic layer 14 constituting a recording layer, which if the respective Curie temperatures thereof are TC1, TC2, TC3 and TC4, satisfy the relations TC1>TC3>TC2 and TC4>TC3. At the same time, if the magnetic anisotropy of the second magnetic layer is Ku2 and the magnetic anisotropy of the third magnetic layer is Ku3, the relation Ku3>Ku2 is satisfied.

Abstract: A component for use in a disc drive includes a component substrate having a substrate surface. A self-assembled image layer is formed over the substrate surface. The self-assembled image layer includes a developed region defining a feature with a developed width. Each component also includes a feature layer that is self-assembled over the image layer. The feature layer is joined by a self-assembly process to the developed region. The feature layer has a feature width that is limited to the developed width.

Abstract: An optical information recording medium in which the ranges of the refractive index and thickness of a protective layer in a case where the protective layer is constituted by a plurality of layers are newly specified and the refractive index and thickness of the protective layer are determined in these ranges, thereby ensuring that even if variation in thickness of the protective layer to ±3 &mgr;m is tolerated, spherical aberration in the optical information recording medium is substantially to within 30 m&lgr;rms.

Abstract: The idea here is to have more writing and imprinting space on 3.5, zip diskettes and CD Rom, DVD disk by allowing them to be flipped over to use their other sides.

Abstract: A magnetic recording medium, which includes a substrate and an amorphous magnetic layer, made of an amorphous magnetic material, for magnetic recording of data, is provided with an underlayer between the substrate and the amorphous magnetic layer, the underlayer being made of amorphous metal element, and having a mean thickness of 10 nm or less. In this manner, movement of magnetic domain walls of the amorphous magnetic layer is effectively limited by minute irregularities on a surface of the underlayer. This realizes a stable formation of a minute recording mark. This realizes recording having a sufficient signal quality, even when the high-density recording is performed by forming such a minute recording mark that a shortest length of the recording mark is less than 100 nm. Moreover, this allows the magnetic recording medium to have a simplified layer structure.

Abstract: Disclosed are magneto-optical recording media including at least a reflection layer, a recording layer and a dielectric layer laminated on a substrate in this order, wherein the thickness of the dielectric layer is not less than 140 nm or wherein the dielectric layer is provided by the lamination of upper dielectric layer and lower dielectric layer in which the thermal conductivity of the upper dielectric layer is higher than that of the lower dielectric layer. By arranging the thickness of the dielectric layer in a specific range, the surface roughness of a media in not more than 1.5 nm, and providing a reflection layer composed of a noble metal alloy, achieved is a magneto-optical recording medium able to record constantly in near-field magneto-optical recording, suitable for narrow track pitch, and having excellent SNR, resolution, and recording sensitivity.

Abstract: An optical information recording medium 10 is composed of at least a reflective layer 2, a first protective layer 3, a phase-change type optical recording layer 4 and a second protective layer 5 being sequentially laminated on a substrate 1. The optical information recording medium 10 is conducted to record information by changing a phase of the phase-change type optical recording layer 4 by irradiating light from the second protective layer 5 side. The phase-change type optical recording layer 4 further contains at least Ti, In, Ge, Sb and Te. When each content amount of the Ti, In, Ge, Sb and Te is defined as v, w, x, y and z in atomic percent respectively, each content amount of v, w, x, y and z in atomic percent satisfies following relations: 0.3≦v≦4, 0.3≦w≦3, 3.4≦x≦14.5, 2.1≦y/z≦4 and v+w+x+y+z≦100.

Abstract: The present invention is a magneto-optical disk adopting the magnetic domain wall displacement detection type ultra-high resolution playback method. The magneto-optical disk has a recording track whose width Tw given as Tw≦0.046×(&lgr;/NA), where &lgr; is a wavelength of a laser light which is irradiated to a magneto-optical disk to play back recorded signals recorded on the magneto-optical disk and NA is a numerical aperture. Thus, the detrack tolerance can be 160 nmpp or more, which is contributed to easier design of the disk drive tracking.

Abstract: An optically readable information disc (150, 250, 350, 450, 550, 850) is disclosed as having an upper major surface (152), a lower major surface (156, 554, 854) and at least a peripheral edge (162) joining the major surfaces, further including engagement mechanism (164, 252, 352, 452, 456, 552) along at least part of the peripheral edge for engagement with a holder (100, 200, 300, 400, 500).

Abstract: The compact disc storage capacity is based on the surface area used in the placement of the data track, in light of this, the extended capacity compact disc is nothing more than an optical disc with increased surface area by adding folds, bends, creases or crimps to the various information storage materials used in the manufacturing process of all current models optical discs (polycarbonate plastic at present).

Abstract: An optical information recording medium including a substrate, a recording layer formed on the substrate, and a transparent sheet provided on the recording layer via an adhesive layer. The adhesive layer has a peak of loss modulus at a temperature of 0° C. or lower, and exhibits an E1′/E2′ ratio of 2.0 or less, wherein E1′ and E2′ represent storage moduli of the adhesive layer at 25° C. and 80° C., respectively.

Abstract: A domain-wall-displacement-type magnetooptical recording medium is provided in which a floating magnetic field from a surrounding portion that operates on a recording/reproducing portion is suppressed. The recording medium includes a displacement layer having a composition such that rare-earth-element sub-lattice magnetization is dominant at room temperature, a switching layer, a memory layer, and a magnetization compensation layer in which iron-family-element sub-lattice magnetization is dominant at room temperature, for suppressing generation of a stray magnetic field at a temperature near room temperature.

Abstract: A manufacturing method of a domain wall displacement type magneto-optical recording medium comprises the steps of depositing a magnetic layer on a substrate to prepare a disc, and irradiating the magnetic layer with a converged light beam while applying a magnetic field and annealing the magnetic layer a converged light beam between information tracks.

Abstract: In an optical disk, a recording film and a reflection film have different inner diameters. The optical disk includes a printed label having an inner diameter greater than the inner diameter of the reflection film. The inner diameter of the label is smaller than that of the recording film. An adhesive layer is directly in contact with first and second substrates. Therefore, sufficient adhesion strength is assured.

Abstract: An optical storage medium having an optically-transparent flexible substrate, a reflective layer bonded to the substrate surface, and a print layer bonded to the reflective layer, where the print layer also includes a modified print layer region such as a lenticular region, a diffractive optical element, an embossed region, a holographic image, a magnetostrictive ferromagnetic material electronic article surveillance tag, or a radio-frequency surveillance tag. The layers are individually formed and laminated together, the laminated combination subsequently cut into a plurality of discs.

Abstract: An optical information medium is provided. The medium comprises a supporting substrate, an information recording layer thereon, and a light-transmitting layer thereon and a recording or reading laser beam enters the recording layer through the light-transmitting layer, and in such medium, recording/reading characteristics are improved when the beam spot of a laser beam has a small diameter and the linear velocity is high with the function of the light-transmitting layer to protect the information recording layer maintained at a sufficient level. Also provided is a medium wherein storage stability is improved.

Abstract: An optical recording medium has a user data area and a lead-out area, wherein the user data area and the lead-out area each has grooves and lands formed thereon. Wobbles are formed on at least one lateral surface of grooves of the user data area and the lead-out area, and configured such that wobble characteristics are made different between the user data area and the lead-out area. Different types of wobbles are formed on the grooves of either the user data area or the lead-out area, thereby preventing an optical pickup that performs recording/reproduction from deviating from the user data area. Also, in a multi-layer optical recording medium, a whole area of a recording layer is configured to have a same condition, thereby preventing deterioration in reproduction and/or recording due to a difference in light power transmittance of another recording layer.

Abstract: An initialization method of an optical recording medium having a plurality of optical recording layers capable of reducing uneven initialization due to light interference caused at the time of initialization without deterioration of information recording/reproducing signal characteristics of the recording layers is provided.

Abstract: The optical data storage medium (20) has a substrate (1) with a surface area having tracks (4) of marks representing stored information. The information is readable by means of a scanning radiation beam (10). A reflective layer (2) is present, reflecting the radiation beam (10). The medium has a radiation beam (10) reflection larger than 50%. The reflective layer (2) comprises a compound of the formula Al100-y,Xy, in which formula Al is aluminum and X is an element selected from the group of Ge and Si. The letter y is the atomic fraction of X in at. %. The value of y is in the range 5<y<35. The reflective layer (2) has a radiation beam absorption, which enables controlled ablative recording or solid-phase change recording of an identification mark (6, 6′).

Abstract: An optical recording medium includes a substrate, a protective layer, three or more information recording layers formed between the substrate and the protective layer and transparent intermediate layers each formed between neighboring information recording layers and capable of recording data in the three or more information recording layers and reproducing data recorded in the three or more information recording layers by projecting a laser beam onto the three or more information recording layers via a light incidence plane constituted by the surface of either the substrate or the protective layer, wherein neighboring transparent intermediate layers facing each other across an information recording layer have different thicknesses. According to the thus constituted optical recording medium, it is possible to reduce interlayer cross-talk.

Abstract: By not recording a signal which can be the subject of focussing on a disc, a simple and inexpensive lens cleaner is provided which is able to perform cleaning of an object lens in a simple and reliable manner, without causing the disc to rotate, even in a standard disc device. In order to clean the object lens of the optical disc device, a bristle brush which makes contact with the object lens is provided on the disc, an operating ribbon for operating the disc from the outside of the device is attached to the disc, and no recording face that can be the subject of focussing by the object lens is provided, or alternatively, no signal that can be the subject of focussing by the object lens is recorded, on the face of the disc adjacent to the object lens.

Abstract: An information recording medium from which data can be read stably even when a label for the information recording medium is adhered thereon is provided. A label is partially attached to an information recording member in which an information recording layer is formed on a substrate.

Abstract: An optical recording medium is provided, which includes: a substrate; a recording layer formed on the substrate, on which information can be recorded using laser light; and a protective layer or a protective substrate provided on the recording layer; and is characterized in that a water-based ink receiving area and a water-insoluble ink receiving area are formed on the protective layer or the protective substrate, and the water-insoluble ink receiving area comprises a substantially rectangular smooth area. The substantially rectangular smooth area is preferably formed of water-insoluble ink or a water-insoluble material. The substantially rectangular smooth area preferably has an area of at least 5 cm2.

Abstract: A mold and a process for use in producing data storage articles such as single substrate double-sided disks. In one configuration, a mold for manufacturing a substrate includes a stamper, at least one holder having an interface with the stamper, and a vacuum line for applying a retention force to maintain the interface between the holder and the stamper. In another configuration, the mold includes a demolding line for applying a demolding force to the substrate to aid in separating the substrate from the stamper. The various embodiments of the present invention provide, among other things, easier and faster stamper changeover, substrates and final data storage articles having improved process indicia such as thickness, flatness, inner and outer diameter, and concentricity, and facilitates production of single-substrate double-sided disks.

Abstract: An annular protective ring attachment designed to grip the outer peripheral edge of all compact discs (CDs) and digital video discs (DVDs) which, when used in combination with said CD or DVD, creates an airfoil. The airfoil ring consists of an inner periphery, which is molded to form a top lip (3) and bottom lip (4), and between these lips, a gripping mouth (6), which securely holds the CD or DVD (7,76) inside the aperture of the airfoil ring. The body of the airfoil ring is curved in such a way as to create an airfoil adequate to enable the airfoil ring with inserted CD or DVD to be safely tossed into the air and to exhibit controllability in flight. The airfoil ring is constructed of a soft, flexible plastic material, and uses a hinge groove (5) on the top side of the airfoil skirt (1) and a hinge groove reaction area (9) on the underside of the airfoil skirt (1) to dissipate the contact force upon impact and create a cushioning effect so as to avoid resultant injury or damage when tossed into the air.