Matches 451 - 500 out of 1104 < 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 >
Match Document Document Title
5307228 Magnetic field damage indicator  
A magnetic field indicator is provided which visually indicates the presence of a potentially harmful magnetic field by means of a magnetically responsive additive. In one embodiment, the additive...
5307223 Magnetic recording disk file for contact recording  
A magnetic recording disk based on conventional disk technology has both an extremely smooth top surface and high coercivity, and is incorporated in a contact recording disk file which requires an...
5303102 Disk drive apparatus having head guard  
A disk drive apparatus for recording and reproducing desired information on and from floppy disks, is simply and thinly structured and has an excellent shock resistance. The disk unit includes a...
5302434 Magnetic recording disk for contact recording  
A magnetic recording disk based on conventional disk technology has both an extremely smooth top surface and high coercivity, and is incorporated in a contact recording disk file which requires an...
5296995 Method of magnetically recording and reading data, magnetic recording medium, its production method and magnetic recording apparatus  
The present invention uses a magnetic recording medium equipped with those magnetically readable recording servo pits which are preformed on a magnetic recording medium and have different magnetic...
5289456 Method of forming a magneto-optical disk hub in which the inner peripheral edge portion of the spindle opening is strengthened and made abrasion resistant  
An optical disc equipped with a hub having a centering hole into which a spindle shaft of a disc driving mechanism is inserted, wherein a centering hole portion of the hub is provided with a...
5285343 Magnetic disk with surface protective layer having convex portions and magnetic disk apparatus including such a magnetic disk  
There is provided a magnetic disk apparatus including at least one magnetic disk having a magnetic layer and a surface protective layer on a substrate; a magnetic head which faces the magnetic disk...
5283773 Steering laser beam while etching optical servo tracks for magnetic disks  
A beam of light used to etch servo tracks on a magnetic disk is steered with an acousto-optical device to maintain the beam in concentrical patterns while mechanically moving the optics which...
5283133 Magneto-optical disk  
A magneto-optical disk comprising a substrate, a dielectric film made of aluminum germanium nitride disposed on the substrate and a magnetic film disposed on the dielectric film. The...
5280401 Magnetic recording medium, method for producing same and magnetic recording apparatus  
The magnetic recording medium includes a nonmagnetic substrate having different values of surface tension corresponding to surface free energy in a predetermined magnetic recording direction and in...
5278703 Embedded servo banded format for magnetic disks for use with a data processing system  
A data processing system records information on magnetic disks in a format in which sector headers, which include embedded servo information, are radially aligned and recorded at a single frequency...
5274511 Servo signal recording method and apparatus  
An external position detector is mounted on a head arm that also carries a transducer for tracking a magnetic disk. When the head arm is moved at constant speed, the position detector produces an...
5273598 Optical disc manufacturing method  
An optical recording disc which includes a pair of recording disc substrates opposed to each other with a space there between with a hub situated at the central portion of the disc substrates so...
5268799 Magnetic recording and reproducing apparatus  
In a magnetic recording and reproducing apparatus of a type wherein a magnetic disk having a magnetic recording layer formed on a rigid substrate is rotated at a high speed and magnetic recording...
5265086 Information recording disk  
An information recording disk formed from two substrates with a stepped central opening for receiving a hub within the stepped recess of at least one of the substrates is provided. In one...
5262907 Hard disc drive with improved servo system  
A hard disc drive having a digital servo system for controlling the position of a servo head on a dedicated servo surface. The servo surface is formatted in a series of consecutive frames along...
5258973 Method of pre-processing over-write capable magnetooptical recording medium, and pre-processed over-write capable magnetooptical recording medium  
An over-write capable magnetooptical recording medium is pre-processed by subjecting a track separation zone to a pre-processing field which aligns the magnetization of a recording layer in a...
5257388 Device for detecting whether an attached external memory stores valid data, if not, whether the external memory is capable of storing data  
In a data processing device capable of attachably and detachably providing an external memory unit to which data are written and from which data are read, the external memory unit being capable of...
5257154 Recording medium disk with clearance for adhesive bond  
A disk is provided with discontinuity between a surface of a circumferential portion of a disk base defining a plane for installing a recording medium sheet and a bonding surface provided outside...
5253124 Apparatus for forming recording tracks on disks with different track-number formats  
A disk recording apparatus being compatible with disks whose storage capacity is different, in which a first and a second recording mode can be set. In the first recording mode, linear track...
5249176 Optical recording medium, process for preparing the same and its optical recording and reproducing system  
An optical recording medium, comprising a substrate and a recording layer covered on the outer surface with a protective member comprising a heat-shrinkable material subjected to heat shrinkage, a...
5249093 Magnetic disk  
A magnetic disk comprises an annular resilient magnetic recording mediumm, an outer ring having an outer affixing surface, and an annular frame disposed radially inwardly of the outer ring. The...
5241442 Alignment disk  
In the present alignment disk for adjusting the tracking and azimuth of a magnetic head, a track includes adjacent first and second regions which are circular and substantially concentric. First...
5240784 Magnetooptical recording medium  
A multi-layer magnetooptical recording medium capable of overwriting with magnetic field modulation method, includes: a first layer having perpendicular magnetic anisotropy and composed of a...
5235478 Disc drive apparatus with servo tracks offset from data tracks  
A disc drive apparatus with a tracking servomechanism, comprising at least one disc medium having data surfaces where servo signal and data signal are recorded; transducer means having a first head...
5233575 Magneto-optical recording medium  
A magneto-optical recording medium capable of overwriting which comprises a substrate, a magneto-optical recording layer provided on the substrate, a recording auxiliary layer provided on the...
5232790 Magneto-optical recording disc and method of producing it  
The refractive index of a dielectric layer between a transparent substrate and a magneto-optical recording layer is varied across the thickness, with a portion of the layer on the substrate side...
5227212 Magnetic recording disk, magnetoresistive read head, inductive write head combination  
An improved CoPt based or CoNi based alloy magnetic recording disk for horizontal recording has a magnetic recording layer which is a laminated structure of relatively thin magnetic alloy films...
5226033 Magneto-optical disk hub in which the inner peripheral edge portion of the spindle opening is strengthened and made abrasion resistant  
An optical disc (2) equipped with a hub (5) having a centering hole into which a spindle shaft of a disc driving mechanism is inserted, wherein a centering hole portion of the hub is provided with...
5225955 Disk-shaped magnetic recording medium having novel textured surface  
A novel magnetic recording medium has a texture consisting of a multiplicity of circumferential stripes which intersect the circumferential direction at an angle of 0.1°-20°. The friction...
5224216 Computer diskette drive communication interface  
A coupler of the present invention advantageously renders the read/write head of a diskette drive of a computer a data transfer port and preferably an input/output port suitable for connection with...
5212615 Data storage device having stretched and distended magnetic media surface  
A data storage device having two distended and stretched magnetic media surfaces. The magnetic media has a backing which is distended when secured to a core body of the device. A shell surrounds...
5210673 Thin-film hard disk magnetic medium  
A thin-film hard disk magnetic medium comprising a magnetic recording film made from a magnetic metal alloy formed on a circumferentially textured surface of a substrate, in order that the surface...
5210672 Magnetically indelible media type identification system  
A diskette comprising a jacket, a liner material disposed within said jacket, a flat circular media having a magnetic coating on both sides disposed within said liner material, a hub attached at...
5206844 Magnetooptic recording medium cartridge for two-sided overwriting  
A magnetooptic recording medium cartridge which accommodates a double face type disk-like magnetooptic recording medium with which an overwriting can be performed by modulating only the intensity...
5206773 Magnetic recording disk  
A magnetic recording disk with a central hub including a core member having a central aperture, a ring member mounted on the core member, a covering member, a leaf spring and a pulse generating...
5202810 Magnetic disk having an improved surface configuration  
A magnetic disk includes a non-magnetic substrate with a surface processed layer having fine irregularities formed at least on a main surface thereof, and at least thin film magnetic film and a...
5196970 Magnetic disc apparatus  
A magnetic disc apparatus having at least one magnetic disc having a plurality of track groups thereon at different distances from the center of the disc each of which groups comprises plural data...
5193034 Magnetic disk apparatus of constant-density recording type, magnetic disk used therefor and servo-writing device for patterning on the magnetic disk  
A constant-density type of magnetic disk apparatus is made up of a plurality of magnetic disks, wherein at least one of the surfaces of the magnetic disks is a servo face divided into a plurality...
5192626 Optical recording medium  
An optical recording medium comprising a transparent dielectric layer as a protecting and/or enhancing layer is provided, wherein the transparent dielectric layer is made of an oxide of at least...
5189585 Floppy disk with head slot in liner cut from liner material with preferred orientation  
A 3.5 inch floppy disk is provided with a nonwoven microfiber positioned between the thin magnetic disk and the rigid shell. The liner is fixed to the inside surface of the shell, and has a disk...
5187022 Magnetic recording medium for encoders  
To construct a magnetic recording medium to be used for an encoder adapted for detection of an angular or linear displacement of a mobile object such as a robot arm, a substrate is at least partly...
5182693 Magnetic disk  
A magnetic disk suitable for high density recording and reproduction of information wherein said disk is a coating type disk comprising a rigid substrate having a magnetic layer coated thereon from...
5182682 Sectored servo disk formatting  
A sector on a disk contains position information used to determine position error of a transducer over the disk. The sector has a normal field with a first side and a second side. The first side is...
5166006 Textured thin-film substrate and method  
A method of forming an isotropic texture having a selected summit density and surface roughness in a selected inner-diameter annular zone of a thin-film medium substrate having a polished metal...
5144618 Optical disc medium  
An erasable optical disc medium on which information is recorded and read by using a laser beam, which comprises (i) a phase transition type information recording layer, (ii) an optical...
5144512 Magnetic recording disk having textured surface  
A magnetic recording disk comprising at least a magnetic layer on a circular rigid substrate with a physically abraded surface having a uniform series of physical circumferential texturing, wherein...
5140486 Magnetic recording and reproduction  
Information is magnetically recorded in and reproduced from a magnetic disk using a flying magnetic head. The disk is a coating type disk comprising a rigid substrate having a magnetic layer coated...
5138511 Magnetic recording disk in which the level of the surface of the data tracks, and servo tracks is higher than that of the guardbands  
A magnetic recording disk in which the level of the surface of the data tracks and servo tracks is higher than that of the guardbands.
5136450 Disc pack assembly having a laminate sleeve disposed between a spindle and a disc, for reducing radial disc displacement  
A disc pack assembly utilized in a Winchester hard disc drive includes a rotatable cylindrical spindle and at least one disc mounted on the spindle for rotation therewith. A laminate sleeve...
Matches 451 - 500 out of 1104 < 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 >