Abstract: A heat-assisted magnetic recording (HAMR) device includes a controller that selects a power for operating a heat source for a data write to a target data track. According to one implementation, the controller selects the power based on an assessment of whether the target data track is bounded by any data-storing tracks. A first power is selected when the data track is not bounded by any data-storing tracks and a second lower power is selected when the data track is bounded by one or more data-storing tracks. In another implementation, the controller writes to different partitioned regions of a storage media with different powers of the heat source. The controller selects a storage location for data based on an expected write error rate and environmental conditions within the HAMR device.

Abstract: The present invention relates to a high data density optical recording medium. The invention further relates to an apparatus for reading from such an optical recording medium. The optical recording medium has marks that are arranged in tracks. The tracks have a cross section with a curved shape and protrude above a surface of the optical recording medium.

Abstract: An optical recording medium is provided with at least a substrate, light absorbing and heat generating parts each of which absorbs light and generates heat, and recording parts, and each of the recording parts are formed between two recording tracks.

Abstract: An information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: An information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: An information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: An information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: An information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: An information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: A magneto-optical recording medium in which the inside of grooves formed along recording tracks is a signal recording area in groove recording, and the domain wall displacement detection method is employed; and a curvature radius R1, in the cross section perpendicular to the recording tracks, of a shoulder portion of a land separating the grooves that is adjacent to the groove is 30 nm or less and a curvature radius R2, in the cross section perpendicular to the recording tracks, of the inside edge portion of the groove for the recording that is adjacent to the land is 20 nm or more, so that a wide recording power margin can be obtained, the jitter can be improved, and the error rate can also be improved.

Abstract: An information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: A thermally assisted magnetic recording medium includes a substrate having a first surface and a second surface opposite to the first surface. A recording layer is formed on the first surface of the substrate. A plurality of thermally conductive regions are provided at the first surface of the substrate to extend in parallel to each other and about the center of rotation of the recording medium. The thermally conductive regions have a higher thermal conductivity than the substrate, and are at least partially embedded in the substrate.

Abstract: An information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: An integrated micro-optical system includes at least two wafers with at least two optical elements provided on respective surfaces of the at least two wafers, at least one of the two optical elements being a spherical lens. The resulting optical system presents a high numerical aperture. One of the optical elements may be a refractive element formed in a material having a high index of refraction.

Abstract: A domain wall displacement detection (DWDD) system magneto-optical recording medium forms a land 3 and a groove 4 as signal recording areas. When a domain wall displacement improvement is changed by irradiating annealing light La on a boundary wall surface 5 between the land 3 and the groove 4, the position of this annealing light is detected by an annealing light scanning position displacement detecting wobbling portion 7 formed at a portion extending along the recording track length direction of the boundary wall surface 5. The annealing light scans this wobbling portion 7, whereby a vibration amplitude of a cycle corresponding to the cycle of the wobbling portion 7 is produced to thereby detect and monitor the miniscule change of the scanning position of the annealing light with high sensitivity. Thus, in the DWDD system magneto-optical recording medium, the scanning position of the annealing light at the boundary wall surface between the land 3 and the groove 4 can be detected with high sensitivity.

Abstract: A method for manufacturing a magneto-optical recording medium in which reading of recorded information is performed through domain wall displacement in a reproduction layer is provided, in which magnetic separation of groove side-wall portions is performed more reliably; as a result a magneto-optical recording medium with satisfactory recording and reproduction characteristics can be provided.

Abstract: A magneto-optic recording medium has a stacked structure composed of a memory layer, a domain wall displacement layer having domain wall-resistant magnetism smaller than the memory layer, and a switching layer having a lower Curie temperature than these layers interposed between these layers. A recording surface of the magneto-optic recording medium is divided into a plurality of tracks of a predetermined track pitch. A domain wall displacement layer has a recording track region limited in a track width direction in a central portion of each track. A magnetized state of a vertically magnetized memory layer is only transferred in the recording track region. A buffer region is magnetically oriented in an in-plane direction at a predetermined temperature or lower and is vertically magnetized at the predetermined temperature or higher.

Abstract: A record mark is formed on a master disc DS. The record mark is formed substantially along a spiral standard locus, but a record mark position is displaced in a direction crossing the spiral standard locus according to record data. A wobble is formed such that the average value of the displacement of the record mark position is zero for each predetermined data unit with the standard locus as a reference.

Abstract: An optical disc drive apparatus has: a rotation angle counter cleared when the number of pulses in a frequency multiplied FG signal has reached a value corresponding to one rotation of the disc; a switching sector detector detecting polarity switching locations based on the output signal of an RF processor to clear the rotation angle counter; a switching window signal generator generating a switching window signal having a predetermined width based on the count value; a timing signal generator generating a timing signal for each sector based on the output signal of the RF processor; and a polarity switching signal generator generating a polarity switching signal based on the switching window signal and the timing signal.

Abstract: An optical disk recording method of recording data on an optical disk by applying laser light to a track of the optical disk, includes the steps of a) driving a plurality of laser light sources in sequence in a time division manner, and applying a light flux to one track of the optical disk successively, and b) producing a plurality of rows of record marks in the one track.

Abstract: A magneto-optical recording medium in which the inside of grooves formed along recording tracks is a signal recording area in groove recording, and the domain wall displacement detection method is employed; and a curvature radius R1, in the cross section perpendicular to the recording tracks, of a shoulder portion of a land separating the grooves that is adjacent to the groove is 30 nm or less and a curvature radius R2, in the cross section perpendicular to the recording tracks, of the inside edge portion of the groove for the recording that is adjacent to the land is 20 nm or more, so that a wide recording power margin can be obtained, the jitter can be improved, and the error rate can also be improved.

Abstract: The invention is a magneto-optical recording medium characterized by containing at least a soft magnetic layer, a protective layer, a resin layer having a servo pattern formed thereon, a reflecting film, a lower dielectric material film, a recording film, an upper dielectric material film, and a cover layer, formed on a substrate in this order.

Abstract: A magneto optical recording medium capable of stable recording and readout using a DWDD system is provided. The magneto optical recording medium of the present invention comprises an optical disk substrate and a multilayer recording film comprising essentially a readout layer, an intermediate layer, and a recording layer successively formed on top of the substrate. The readout layer has a smaller magnetic domain wall coercivity than the recording layer. The intermediate layer comprises a magnetic layer whose Curie temperature is lower than the readout layer and the recording layer. A recorded/readout magnetic domain corresponding to recorded/readout information is formed only in a groove area of the optical disk substrate. The thickness of the recording film at the boundary between mutually adjacent recording track areas is smaller than the thickness of the recording film in the center portions of the recording track areas.

Abstract: Information is recorded on an information recording medium such as a magneto-optical recording medium, having two recording tracks arranged alternately, typically in a double spiral manner. The two recording tracks have different recording characteristics and information is firstly recorded on the recording track less liable to cross write, typically on a land section, and subsequently on the recording track more liable to cross write, typically on a groove section.

Abstract: An information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: An optical information-recording medium having in-groove pits, which is excellent in recording and reproduction characteristics and tracking characteristics, is provided. A method for producing the optical information-recording medium is also provided. Further, a stamper to be used for producing a substrate for the optical information-recording medium and a method for producing the same are also provided. In the optical information-recording medium of the present invention, the in-groove pits, which have flat bottom surfaces, are arranged on a groove which has a flat bottom surface.

Abstract: An optical disk is made of tracks that are magnetically separated from one another by scanning a focused light beam over lands between tracks at a predetermined power and annealing to lower the magnetic anisotropy of a magnetic layer on the lands, and is provided with a power testing region comprising one or more tracks for finding the predetermined annealing power at the location of at least one of the group consisting of a specific region within the data region, a region more to the inner side than the innermost track of the data region, and a region more to the outer side than the outermost track of the data region. Thus, an optical disk and a manufacturing method for the same can be provided that have a high recording density and with which annealing can be implemented in a short time and at the correct annealing width.

Abstract: An optical disk of the present invention includes a substrate and a recording layer disposed above the substrate, and reproduces an information signal by a DWDD system, using light incident from the substrate side. The optical disk further includes a first dielectric layer disposed between the substrate and the recording layer and a second dielectric layer disposed on the recording layer opposite to the substrate, wherein the recording layer is initialized with light having a wavelength ? incident from the second dielectric layer side, and the thickness of the second dielectric layer is in a range of ?/(12×n) to ?/(2×n) (where n is a refractive index of the second dielectric layer).

Abstract: A scanning device for scanning data-carrying disks. The disks include a magnetisable layer to and from which data is written and read using a magnetic transducer, such as a Giant Magneto-Resistive (GMR) transducer. Positioning of the transducer over a data track is achieved by optical tracking using a land/groove structure, and positioning of the transducer with respect to the optical tracking system by means of a reference beam transmitted through the disk.

Abstract: A domain wall displacement detection (DWDD) system magneto-optical recording medium forms a land 3 and a groove 4 as signal recording areas. When a domain wall displacement improvement is changed by irradiating annealing light La on a boundary wall surface 5 between the land 3 and the groove 4, the position of this annealing light is detected by an annealing light scanning position displacement detecting wobbling portion 7 formed at a portion extending along the recording track length direction of the boundary wall surface 5. The annealing light scans this wobbling portion 7, whereby a vibration amplitude of a cycle corresponding to the cycle of the wobbling portion 7 is produced to thereby detect and monitor the miniscule change of the scanning position of the annealing light with high sensitivity. Thus, in the DWDD system magneto-optical recording medium, the scanning position of the annealing light at the boundary wall surface between the land 3 and the groove 4 can be detected with high sensitivity.

Abstract: A recording medium is provided, which maximizes the recording capacity and simplifies the configuration of an information recording/reproducing apparatus including a pickup. In the medium, different types of wobbling signals are preformatted in each of the adjacent land and groove signal tracks. A same-phase wobbling signal provided by wobbling each side of the respective land and groove signal tracks in the same phase, and a different-phase wobbling signal provided by wobbling each side of the respective land and groove signal tracks in a different phase are used as the different types of wobbling signals. The physical positions of all the land and groove signal tracks are indicated by the same-phase wobbling signal.

Abstract: An optical recording medium has spirally or concentrically formed tracks and is capable of an optical recording. The optical recording medium includes a data recording and reproducing area divided into a plurality of zones in the radial direction. One zone is divided into a plurality of sectors respectively having an address part including pits having address information and a data part only composed of grooves. The number of sectors forming each zone is different. An optical disc is formed so that an average reflectance Iadd of the address part and an average reflectance Idata of the data part satisfy a relation expressed by 0.7≦(Iadd/Idata)≦1.3 or 0.8≦(Iadd/Idata)≦1.2.

Abstract: An optical recording medium used as a recording medium for information signals in which, in forming a groove along a recording track, a first groove and a second groove are formed to a first depth x to describe a double helix and a third groove having a second depth y shallower than the first depth x is formed between the first and second groves describing double helices. By setting the phase depths of these grooves to a pre-set range, signals required for tracking servo or seek are obtained to sufficient levels to realize stable tracking servo and seek.

Abstract: A storage medium for thermally-assisted magnetic recording has a recording layer which substantially parallel tracks for recording information. The recording layer includes a series of recording regions, each region comprising a plurality of tracks for magnetically recording information. The tracks in a region have a pitch p, and a region extends a distance ½ p beyond a centre line of the outermost track of the region. Neighbouring regions are separated from one another by magnetically non-recording areas having a width substantially equal to or larger than the pitch p. The writing of one region does not have thermal cross-talk on other regions.

Abstract: A reproduction-only optical information storage medium including a plurality of areas and at least one transition area. Each transition area is located between two adjacent areas. The transition area allows data to be smoothly reproduced from the reproduction-only optical information storage medium at a low error generation rate. Also, since the optical information storage medium provides standards for the transition area, it is compatible with existing optical information storage media.

Abstract: There is disclosed an information recording medium comprising a guide groove for recording/reproducing information in an information recording region, the information is formed as a recorded mark both in concave and convex portions of the guide groove, management information including address information is recorded by a wobble of the guide groove, and the wobble is formed in such a manner that an offset of a reproducing signal of the recorded mark generated by the wobble of the guide groove is 5.5% or less of an amplitude of the reproducing signal.

Abstract: An optical disk recording method of recording data on an optical disk by applying laser light to a track of the optical disk, includes the steps of a) driving a plurality of laser light sources in sequence in a time division manner, and applying a light flux to one track of the optical disk successively, and b) producing a plurality of rows of record marks in the one track.

Abstract: The surface of a disk medium includes a substrate whose surface includes grooves and lands. A non-magnetic underlayer and a magnetic recording layer are formed on the substrate. Smoothing non-magnetic film fills the grooves, which are covered with the non-magnetic underlayer and the magnetic recording layer, so that the height of the magnetic recording layer above the grooves may reach the same level as the height of the magnetic recording layer above the lands.

Abstract: This invention relates to magneto-optical recording media such as magneto-optical disks and cards, manufacturing methods of the medium and a magneto-optical recording and playback device to record and play back data using the magneto-optical recording media. The magneto-optical recording medium of the present invention has a recording layer and a reflective layer on a substrate, and the recording layer has a layered structure in which at least one spinel ferrite (or rutile-type oxide or hematite) layer and at least one garnet ferrite layer are piled together. It is preferable that the layered structure is formed on tracks where data are recorded. The manufacturing method of the present invention comprises the steps of heat treatment in the range of 500-700° C., preferably 600-630° C., after the formation of the recording layer.

Abstract: An optical disk of the present invention includes a substrate and a recording layer disposed above the substrate, and reproduces an information signal by a DWDD system, using light incident from the substrate side. The optical disk further includes a first dielectric layer disposed between the substrate and the recording layer and a second dielectric layer disposed on the recording layer opposite to the substrate, wherein the recording layer is initialized with light having a wavelength &lgr; incident from the second dielectric layer side, and the thickness of the second dielectric layer is in a range of &lgr;/(12×n) to &lgr;/(2×n) (where n is a refractive index of the second dielectric layer).

Abstract: As a magneto-optical recording medium capable of obtaining stable tracking servo signals with a narrow tracking pitch with less influences of cross talk and cross write, a magneto-optical recording medium is provided which comprises a plurality of recording/reproducing tracks and wobble pits for a sample servo, wherein each of the wobble pits is provided between two adjacent tracks and used commonly by the adjacent tracks.

Abstract: Structures of storage media for optical storage systems, especially for systems in the near-field configuration to couple radiation between the optical head and the media at least in part by evanescent fields.

Abstract: On a disk-shaped substrate in which a predetermined region ranging in a radial direction is used as a data region for recording/reproduction, a first dielectric layer, a magnetic layer, and a second dielectric layer are provided. The data region includes recording/reproducing tracks composed of a plurality of discontinuous grooves or lands ranging from an innermost track to an outermost track. Magnetic anisotropy of each of magnetic layers positioned between the respective recording/reproducing tracks is reduced to a level lower than that of magnetic anisotropy of the magnetic layers positioned on the recording/reproducing tracks, so that the magnetic layers are magnetically separated only between the recording/reproducing tracks and not magnetically separated in flat portions without grooves. Thus, reflectance is even in the flat portions, thereby allowing tilt detection.

Abstract: A recording/reproducing apparatus is configured to displace near-field light for recording or reproduction and tracking illumination light toward an outer periphery of a recording pit when an off-track state toward the outer periphery occurs. The amount of reflected tracking illumination light increases since the reflectivity of an outer peripheral track band is higher than that of a recording region and that of an inner peripheral track band. The near-field light and the tracking illumination light are displaced toward an inner periphery of a recording pit when an off-track state toward the inner periphery occurs. The amount of reflected tracking illumination light decreases since the reflectivity of the inner peripheral track band is lower than that of the recording region and that of the outer peripheral track band. The single tracking illumination light is required for tracking control.

Abstract: A substrate for an optical recording medium, includes recording tracks formed in guide grooves on a disc; and an address section having an address pit sequence formed between the recording tracks in the guide grooves along an information reading direction of the recording tracks. The recording tracks in the guide grooves are divided into a prescribed number of zones. In each of the zones, the center of the address section corresponding to a recording track in the radially outermost or radially innermost guide groove is disposed so as to shift in a radial direction of the disc in relative relationship to the center of the recording track in the guide groove.

Abstract: A magneto-optical recording medium includes a magnetic reproducing layer having an axis of easy magnetization in a direction perpendicular to its layer surface, a magnetic intermediate layer formed on the magnetic reproducing layer and having an axis of easy magnetization in a plane at a room temperature, and a magnetic recording layer formed on the magnetic intermediate layer and having an axis of easy magnetization in a direction perpendicular to its layer surface. The magnetic reproducing layer has a composition of GdxFeCoy where 22 at %≦x≦25 at % and 16 at %≦y≦23 at %.

Abstract: A storage medium for thermally-assisted magnetic recording has a recording layer which substantially parallel tracks for recording information. The recording layer includes a series of recording regions, each region comprising a plurality of tracks for magnetically recording information. The tracks in a region have a pitch p, and a region extends a distance ½ p beyond a centre line of the outermost track of the region. Neighbouring regions are separated from one another by magnetically non-recording areas having a width substantially equal to or larger than the pitch p. The writing of one region does not have thermal cross-talk on other regions.

Abstract: A magnetically induced super-resolution (MSR) magneto-optical recording medium capable of reproducing a recorded mark smaller in size than a beam spot, having recording tracks consisting of lands and grooves. This magneto-optical recording medium includes a transparent substrate on which the lands and the grooves are alternately formed, a magnetic reproducing layer formed on the transparent substrate, and a magnetic recording layer formed on the magnetic reproducing layer. Each land has a first width, and each groove has a second width larger than the first width. The depth of each groove on the substrate is 60 nm or less, and the track pitch is 0.7 &mgr;m or less.

Abstract: A magneto-optical recording medium is composed of a base which has a property that a light can be transmitted therethrough, a readout layer formed on the base, which has in-plane magnetization at room temperature, whereas, a transition occurs from in-plane magnetization to perpendicular magnetization as the temperature thereof is raised and a recording layer formed on the readout layer for recording information magneto-optically. A recording and reproducing method and the optical head are designed for the magneto-optical recording medium. By the recording and reproducing method using the optical head, information recorded at high density can be reproduced.

Abstract: An over-writable magneto-optical recording medium in which a recording section has at least a first dielectric layer, a first recording layer, a second recording layer, and a second dielectric layer formed sequentially and a reflective layer and a protective layer formed on the recording section. A groove is formed on the transparent substrate along a recording track, both sidewalls of the groove are formed into an independent wobbling shape, a relationship of 0.470 ≦W/Ø≦0.610 is effectuated where the width of the groove as W, and a relationship of 0.120≦D(&lgr;/n)≦0.142 is effectuated where the depth of the groove as D, and the angle Ø between wall faces of the groove is 150°±10. a relationship of 0.55≦(d2/d1)≦0.9 is effectuated when assuming the thickness of the first dielectric is d1 and the reflective layer is d2.