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Match Document Document Title
7215504 Disk drive using an optical sensor to detect a position of an actuator arm  
A disk drive is disclosed comprising a disk, an actuator arm, a head coupled to the actuator arm, a base, and an optical sensor operable to detect a position of the actuator arm. The optical sensor...
7012777 Disk drive with capacitance sensing of disk vibration and feedforward control for removal of read/write head track misregistration  
A data recording disk drive has a plurality of capacitive sensors, each sensor facing a surface of an associated disk, a capacitance sensing circuit for converting the sensed capacitance to a...
6977791 Media servowriting system  
A system and methods for efficiently performing media writing functions is disclosed. The system and methods include: detecting media movement with respect to a base and heads during reading and...
6950270 Adaptive index reference position qualification  
Method and apparatus for performing a seek operation to move a data transducing head from an initial track to a destination track on a rotatable recording surface. A servo control circuit operates...
6947243 Method and system for time-shift based rotational vibration sensing in disk drives  
A method (and structure) senses a rotational vibration of a disk drive. The disk drive includes a rotating disk. The disk includes a plurality of reference bits across a surface thereof. The method...
6924958 Read/write transducer for hard disk drives with optical position measuring system, and manufacturing process thereof  
Described herein is a read/write transducer for a hard disk drivewith dual actuation stage, comprising at least one hard disk and at least one suspension carrying the read/write transducer. The...
6920010 Magnetic recording apparatus  
A magnetic recording apparatus which, even when crosstalk occurs between signals from three photosensitive parts of a photodetector, can detect a high-precision tracking error signal with...
6898046 Method and system for rotational velocity-based algorithm for vibration compensation in disk drives  
A disk drive (HDD) (and method) subject to linear and rotational vibration, includes an independent sensing unit for sensing a rotational velocity component of the rotational vibration in a...
6856484 Magnetic servo of a recording head  
A method of aligning a magnetic read/write head to data tracks on a magnetic surface of a digital linear tape. The method includes writing a signal over a track of optical servo marks located on...
6829115 Method and apparatus for measuring half frequency whirl in a spindle motor  
An apparatus and method of indirectly measuring half frequency whirl in a spindle motor having a rotor adapted to rotate a disc having a track which is followed by a transducer head that is...
6747832 Disk apparatus and head position control method  
A disk drive has a data recording medium such as a disk, a spindle motor for rotating the disk, disk rotation speed controlling logics for supplying a spindle current to the above described spindle...
6735036 Control of data sensor fly height  
A data storage device includes a head suspension assembly having an attached airfoil. The airfoil is coupled to an active (i.e., movable) element that responds to signals from height control...
6721113 Method of recognizing master disk positioning mark  
A positioning mark of a soft magnetic film is provided at the center of a master disk, and a beam from a light source irradiates the position of the mark. When a optical reception sensor using a...
6683744 Magnetic disk evaluation apparatus and method  
A magnetic-disk evaluation apparatus includes a magnetic head positioned relative to a magnetic disk including temporary servo signals. Fluctuation of a magnetic head in a seek direction is...
6631047 Interference device, position detecting device, positioning device and information recording apparatus using the same  
An apparatus having a first system for forming a composite light beam of two light beams to be made to interfere with each other, a splitting member for amplitude-splitting the composite light beam...
6580581 Recovery of lateral position of a servo system with respect to longitudinal servo bands of a magnetic tape  
A servo system and method position a head laterally with respect to magnetic tape longitudinal defined servo bands arranged in a longitudinally shifted pattern for identification, and separated by...
6549360 Magnetic recording medium with laser-formed servo-marks  
A magnetic recording medium is formed with a distribution of laser micromachined servo-marks in the form of pits or indentations with an attendant reduction in servo-tracking area and increased...
6535347 Head controlling device in a disk apparatus  
A head-controlling device of a disk apparatus is provided that can precisely move a head stepwise to the position of each track on a recording surface of a disk. When detection output values A1 and...
6504667 Magnetic disk unit and method of manufacture thereof  
A magnetic disk unit which can provide a sufficient PD output of laser beams for optical tracking. The magnetic disk unit comprises a diffraction grating for splitting laser beams from a laser...
6476995 Method and apparatus for reducing track misregistration from servo track writing  
An HDA includes a base, a disc stack coupled to a spindle rotatably attached to the base by a spindle shaft and spindle bearing. An actuator assembly is pivotally attached to the base at a pivot...
6421195 Magnetic disk media with patterned sections  
A magnetic disk medium patterned linear magnetic channels in a radial direction of the disk is employed in a magnetic disk drive unit. The magnetic channels are patterned by high-resolution...
6414807 Method and apparatus for optically sensing accurate clock patterns  
A disk drive system is described for forming and reading precise optically detectable patterns on rotating members of a disk and spindle assembly used in data storage system. In particular the...
6407877 Recording/reproducing method and apparatus in which head driver is unlocked when medium is loaded and when track position information formulation based on optical signal input has been completed  
In a recording/reproducing apparatus, a controller includes a counter responsive to incoming track feed requesting pulses to count the number of the pulses, a head movable state detection unit for...
6307702 Method of writing servo tracks on magnetic disc and device for the same  
The method of the present invention is capable of shortening the time required for positioning an inner actuator and writing servo track signals on a magnetic disc, and improving the quality of the...
6304409 Active damping of actuator bearing translational mode  
Apparatus and method for improving operational performance of a disc drive by detecting and compensating for translational vibration modes in a disc drive actuator. The actuator is configured to...
6304404 Recording medium driving apparatus and tracking method  
A recording/reproducing method and apparatus having the function of tracking a head on a data track formed on a recording medium of a lower-order specifications and on a data track formed on a...
6239938 Multi-actuator optics drive system for laser servowriting  
Drive systems for moving the optics sled in a laser servowriting system used to provide a servo pattern on the media of a magnetic data storage disk are disclosed. The drive systems include...
6225799 Method and apparatus for testing magnetic heads and hard disks  
A method and apparatus for start-stop testing magnetic heads and hard disks in real disk-drive environment is provided. The tester has essentially the same dimensions as a conventional disk drive...
6191911 Positioning apparatus for hard disk servowriter  
A servowriter positioning apparatus for hard disk drives comprises an optical read head 2 for directing three focussed light beams on grating sections formed at the end of a grating member 1...
6128155 High density magnetic recording apparatus including a hologram type magnetic head positioning system  
A magnetic recording apparatus including a magnetic head portion 9, a light emitting portion 10b emitting a light beam, a hologram portion 10a, a light receiving portion 10c, a carriage 12 and a...
6122132 Disk drive head position encoder  
A disk drive head position encoder is for use in a disk drive having a storage media, a read/write head and an actuator configured to control a position of the head. The position encoder includes a...
6057976 Apparatus for detecting rotational displacement information of a rotating object  
An angular division apparatus for circumferentially dividing a rotating object into a plurality of areas by using Doppler pulses includes an optical head for applying a beam emitted from a light...
6055122 Magnetic recording apparatus having a reduced thickness  
A holographic unit for applying light to a recording medium comprises an optical path, a first optical diffracting member, a second optical diffracting member, an optical condensing member, a first...
6034838 Magnetic recording/reproducing device with an improved carriage location detector  
A carriage location detector comprises a scale formed on a carriage and having a plurality of slits at a predetermined interval, a photointerrupter including at least one light emitting element and...
6018440 Flexible disk drive having a position detection unit for detecting a current position of a magnetic head  
In a position detection unit having a scale and a photointerrupter and using in a magnetic disk drive, the scale has a plurality of slits which are equally spaced along a direction in parallel with...
5936788 Method and apparatus for ramp load and unload  
Disclosed is a disk drive having at least one disk for storing data. The disk drive includes at least one transducer for reading or writing data to or from the disk. The transducer is attached to...
5831786 Disk drive having position sensor for ramp load and unload, and method for its use  
Disclosed is a disk drive having at least one disk for storing data. The disk drive includes at least one transducer for reading or writing data to or from the disk. The transducer is attached to...
5774295 Servo track writing technique  
A servotrack writing apparatus (10) having a reference section (30), a workpiece section (32), and a tracking section (34). With the reference section (30) a standard is established without a disk...
5677805 Apparatus for determining the dynamic position and orientation of a transducing head relative to a storage medium  
An apparatus for determining the position and/or orientation of a transducing head positioned on one side of and close to a rotating transparent-core magnetic storage disk. Light is introduced into...
5666236 Velocity control for a disk drive actuator  
A data storage device for reading and writing information to and from a storage medium and having an actuator for moving a read/write head over a surface of the storage medium comprises an optical...
5610777 Method and apparatus for writing servo tracks of a magnetic disk unit which uses a probe to control the positioning of the head  
The present invention relates to a method and apparatus for writing servo tracks of a magnetic disk unit, and has an object of providing a servo track writing method and apparatus which can reduce...
5587852 Disk head driving device using linear activator with multipolar magnets  
The head driving apparatus of the present invention is composed of the following units. A head-provided carriage which moves in a straight line; a plurality of coils fixed on the carriage; a...
5568337 Head positioning using a disk drive mounted to a rotating table  
A device for detecting the position of an information recording or reproducing head relative to a recording medium; the head is relatively rotatable around a first axis with respect to the...
5563868 Optical servo system for magnetic disk  
Coherent light passing through slits produces an optical interference pattern having a fringe spacing related to the spacing of the servo tracks on a magnetic disk. The convolution of the...
RE35302 Magnetic disc apparatus  
A magnetic disc apparatus wherein off-track quantities are stored with regard to reference servo tracks formed circularly in divided data areas on a magnetic disc and, at the time of displacing the...
5371724 Data transducer positioning system with an overrun prevention capability  
A data storage and retrieval system is disclosed which includes a transducer for data transfer with a rotating magnetic disk having a multiplicity of addressable annular data tracks formed...
5353174 Motor speed sensing system for magnetic disk apparatus or the like  
A motor speed control system is disclosed as adapted for the traveling speed control of a transducer on a pivotal support beam driven by a voice coil motor in a rotating disk data storage...
5311378 Dual very-high density magnetic head assembly with optical servo positioning for very high density floppy disk recording and high density format compatability  
A disk system comprising an upper and lower head gimbal assembly, a coarse positioning servo system that includes a stepper motor for 135 TPI operation and a voice coil motor type servo for 1251...
5305159 Magnetic disk apparatus  
A disk system has a disk as a recording medium, and a disk recording/reproducing apparatus for recording and reproducing data by a head radially movable provided on a disk by a head moving...
5291464 Speed and position control apparatus for positioning a movable object  
A speed and position control apparatus comprising: an encoder generating two-phase signals having a 90-degree phase difference to correspond to a movement of a carrier; and adder obtaining a sum of...
Matches 1 - 50 out of 118 1 2 3 >