98results about How to "High track density" patented technology

A thin film magnetic head includes first and second shield layers that are positioned on both sides of a magnetoresistive (MR) stack with respect to a film surface orthogonal direction; a first exchange-coupling layer that is positioned between the MR stack and the first shield layer and that generates an exchange-coupling between a first magnetoresistive (MR) magnetic layer and a first magnetic control layer of the first shield layer; a second exchange-coupling layer that is positioned between the MR stack and the second shield layer and that generates an exchange-coupling between a second magnetoresistive (MR) magnetic layer and a second magnetic control layer of the second shield layer; a bias magnetic field application layer that is disposed at an opposite surface of the MR stack from an air bearing surface (ABS) and that applies a bias magnetic field to the MR stack in a direction orthogonal to the ABS; and pair of side shield layers that are positioned at both sides of the MR stack with respect to a track width direction. Each of the side shield layers includes a pair of magnetic layers that are antiferromagnetically exchange-coupled through a side shield ruthenium layer.

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.

A magnetic recording medium (10) has a substrate (12) and a perpendicular magnetic recording layer (30) formed over the substrate (12). The perpendicular magnetic recording layer (30) has a granular layer (20) in which a magnetic signal is recorded and a continuous film layer (24) magnetically coupled to the granular layer (20). The continuous film layer (24) has hard magnetic portions (204) formed in positions corresponding to the recording regions where magnetic signals are recorded in the granular layer (20) and magnetic shield portions (202) formed between the hard magnetic portions (204), each having a magnetization curve whose slope is larger than those of the hard magnetic portions in the region where the applied magnetic filed is zero when the magnetization curve is measured, and each having a residual magnetic polarization smaller than those in the hard magnetic portions.

A microwave assisted magnetic recording head includes a recording magnetic pole unit that produces a recording field for writing to a perpendicular magnetic recording medium, and a high-frequency magnetic field oscillator that produces a high-frequency magnetic field. The recording magnetic pole unit includes a magnetic core with a write gap portion at which a main recording field component is concentrated, and the high-frequency magnetic field oscillator is disposed in the write gap.

A magnetic recording medium for perpendicular magnetic recording includes a substrate, a granular layer having magnetic crystal grains exhibiting perpendicular magnetic anisotropy and nonmagnetic substances for magnetically separating the magnetic crystal grains from each other at grain boundaries of the magnetic crystal grains, and a continuous film layer having magnetic grains to be exchange-coupled to the magnetic crystal grains, the grain boundary width of the magnetic grains being smaller than that of the magnetic crystal grains, wherein separation regions for magnetically separating tracks from each other are disposed in regions between the tracks of the magnetic recording medium in at least the continuous film layer.

A disc drive includes a transducer having a separate element for writing information and a separate element for reading information to and from the disc. In a disc drive designated to read and write long sequential records, the track misregistration budget is reduced to account for previously written tracks not being encroached on one side. An initial track is written. Subsequent tracks are written after a seek in one direction. The subsequent track is written so that the initially written track is overwritten to one side and leaves a track having a width substantially equal to the width of the read element. Records can be written into data bands of a selected number of tracks. A guard band is left between groups of data bands so that data on tracks in subsequent data bands are not overwritten.

A rotational, shear mode, piezoelectric motor is integrated with a suspension, head or head gimbal assembly (HGA) into a collocated, rotational, shear mode, piezoelectric micro-actuated suspension, head or head gimbal assembly (HGA) for use in disk drives and disk drive manufacturing equipment. When excited by a control voltage, the collocated, shear mode, piezoelectric micro-actuated HGA rotates the head enabling high frequency, high resolution track positioning of the read / write element. The motor is integrated with the head and flexure (collocation). The head rotates about a rotation axis that is ideally located at the center of mass of the head. A shear mode piezoelectric motor rotates the head. A collocated, rotational, shear mode, piezoelectric micro-actuated HGA has high stiffness, high frequency response, high positioning resolution, low mass and low internal vibration for improved tracking, increased track density and greater disk drive storage capacity. Furthermore, its solid integration improves shock resistance and reduces micro-contamination.

Disk drive self-servo writing includes transferring a reference pattern by magnetic printing onto a reference disk, wherein the resulting printed reference pattern includes embedded servo information that provides servo timing and head position information, installing the reference disk and a head into the disk drive, reading the printed reference pattern using the head to generate a readback signal, sampling the readback signal at a sampling rate to generate a sampled signal, processing the sampled signal waveform spectrum to generate a recovered signal including the embedded servo information and fundamental and higher harmonics of the sampled signal, using the embedded servo information from the recovered signal to precisely position and maintain the head at concentric tracks of the reference disk, and self-writing servo patterns onto the tracks with the head.

A magnetic head having at least a main pole having a profile on a magnetic head air bearing surface composed of a first portion having a length in a cross-track direction which continuously increases from a leading edge to a trailing edge, and a second portion located on the side of the trailing edge of the first portion. A length of the second portion in the cross-track direction at the trailing edge is substantially equal to a length in the cross-track direction at the point of contact between the first and second portions. A rate of change in the length of the second portion in the cross-track direction from the leading edge to the trailing edge is different from a rate of increase in the length of the first portion in the cross-track direction.

A TAMR (Thermal Assisted Magnetic Recording) write head uses the energy of optical-laser excited surface plasmons in a scalable planar plasmon generator to locally heat a magnetic recording medium and reduce its coercivity and magnetic anisotropy. The planar plasmon generator is formed as a multi-layered structure in which one planar layer supports a propagating surface plasmon mode that is excited by evanescent coupling to an optical mode in an adjacent waveguide. A peg, which can be a free-standing element or an integral projection from one of the layers, is positioned between the ABS end of the generator and the surface of the recording medium, confines and concentrates the near field of the plasmon mode immediately around and beneath it.

A TAMR (Thermal Assisted Magnetic Recording) write head uses the energy of optical-laser excited surface plasmons in a scalable planar plasmon generator to locally heat a magnetic recording medium and reduce its coercivity and magnetic anisotropy. The planar plasmon generator is formed as a multi-layered structure in which one planar layer supports a propagating surface plasmon mode that is excited by evanescent coupling to an optical mode in an adjacent waveguide. A peg, which can be a free-standing element or an integral projection from one of the layers, is positioned between the ABS end of the generator and the surface of the recording medium, confines and concentrates the near field of the plasmon mode immediately around and beneath it.

A current perpendicular to plane (CPP) having hard magnetic bias layers located at the back of the sensor, opposite the air bearing surface. The bias layer is magnetostatically coupled with the free layer to bias the free layer in a desired direction parallel with the ABS. First and second magnetic shield layers may be provided at either lateral side of the sensor to provide exceptional track width definition. The placement of the bias layer at the back of the sensor makes possible the addition of magnetic shields at the sides of the sensor.

An asymmetric perpendicular magnetic recording head and a method of manufacturing the same, wherein the perpendicular magnetic recording head includes a read head for reading data from a magnetic recording layer and a write head for writing data on the magnetic recording layer. A main pole of the write head has a first surface facing toward the inside of the magnetic recording layer, a second surface opposing a data recording surface of the magnetic recording layer, and a third surface facing toward the outside of the magnetic recording layer and the first surface is asymmetric to the third surface. An angle between one of the first and third surfaces and the second surface may be greater than 90°.

A magnetic read / write apparatus comprises: a recording medium; and a head for writing / reading data to / from each sector on the recording medium; wherein the magnetic read / write apparatus further comprises: a write inhibit slice setting circuit for, when data is written to the recording medium, setting a write inhibit slice for each sector based on the recording state of each sector on the recording medium.

A thin film magnetic head includes a magnetoresistive (MR) stack disposed between first and second shield layers in a direction orthogonal to the film surface; a first exchange-coupling layer that is positioned between the MR stack and the first shield layer; a second exchange-coupling layer that is positioned between the MR stack and the second shield layer; a bias magnetic field application layer that is disposed at an opposite surface of the MR stack from an air bearing surface (ABS); and pair of side shield layers that are positioned at both sides of the MR stack with respect to a track width direction. Each of the side shield layers includes a pair of magnetic layers that are antiferromagnetically exchange-coupled through a side shield ruthenium layer.

A magnetic recording medium is formed by stacking in order, on a nonmagnetic base, at least an underlayer, magnetic recording layer, and protective layer. The magnetic recording layer includes a plurality of magnetic layers and an exchange-coupling control layer, and the magnetic recording medium is characterized in that a physical pattern is formed in the exchange-coupling control layer. The exchange-coupling control layer is located between the magnetic layers of the magnetic recording layer.

A super-resolution material is formed in only a data pit, in a low temperature state of the super-resolution material, reflectivity of each of a pit portion and a space portion and an optical phase difference therebetween are set to be sufficiently small, in a high temperature state, and at least the optical phase difference between the pit and the space is set to be larger than the aforementioned value in an absolute value. Accordingly, by conducting irradiation with an appropriate read power by which substantially only one data track width can be heated to a high temperature state, a good push-pull signal can be obtained even with a track pitch being less than a diffraction limit. At the same time, by an optical device having functions such as a switching means with a DPP type, an offset correcting means of the push-pull signal due to lens shift, a shaping means of the push-pull signal, a learning means of read power, and the like, there is provided an optical disk device that corresponds to the optical disk medium of the present invention and achieves an increase in capacity.

Devices for reading or writing electromagnetic information include a wafer substrate piece disposed between an electromagnetic transducer and an electrostrictive or piezoelectric actuator. The substrate piece is shaped as a rigid body adjoining the transducer and as a flexible element connecting the body and the actuator. To fabricate, at least one electrostrictive layer and many transducers are formed on opposite sides of a wafer that is then cut into rows containing plural transducers. The rows are processed from directions generally normal to the wafer surface upon which the transducers were formed, by removing material to form a head, flexures and a media-facing surface on the head. Conductive leads are formed on a back surface of flexures connecting the transducer with drive electronics. The flexures are aligned with forces arising from interaction with the media surface and from seeking various tracks, reducing torque and dynamic instabilities and increasing actuator access time.

A recording / reproduction element is mounted on a magnetic head slider via a piezoelectric element so that a displacement of the piezoelectric element performs fine control of the position of the recording / reproduction, thus enabling fine spacing and high track positioning accuracy. This improves linear recording density and track density. A pair of electrodes are formed on both sides of a piezoelectric element to constitute a piezoelectric actuator. One electrode is arranged opposite the rear surface (air flow out end) of a magnetic head slider 11. A recording / reproduction element is arranged on and electrically insulated from the other electrode. The piezoelectric element includes a piezoelectric element displaced in a spacing direction, enabling fine spacing control, a piezoelectric element displaced in the track direction, enabling a fine track position control, and a piezoelectric element displaced in a magnetic disc rotation direction, enabling reduction of jitter of a reproduction signal.

Devices for reading or writing electromagnetic information include a wafer substrate piece disposed between an electromagnetic transducer and an electrostrictive or piezoelectric actuator. The substrate piece is shaped as a rigid body adjoining the transducer and as a flexible element connecting the body and the actuator. To fabricate, at least one electrostrictive layer and many transducers are formed on opposite sides of a wafer that is then cut into rows containing plural transducers. The rows are processed from directions generally normal to the wafer surface upon which the transducers were formed, by removing material to form a head, flexures and a media-facing surface on the head. Conductive leads are formed on a back surface of flexures connecting the transducer with drive electronics. The flexures are aligned with forces arising from interaction with the media surface and from seeking various tracks, reducing torque and dynamic instabilities and increasing actuator access time.