Entries |
Document | Title | Date |
20080212228 | MAGNETIC DISK DEVICE AND MAGNETIC RECORDING MEDIUM - A magnetic disk device has a magnetic recording medium in which one servo track and an array of at least one data track are formed alternately. A head portion includes a set of reading heads arranged in a radius direction of the magnetic recording medium for reading signals from the magnetic recording medium, and a controller controls a position of the head portion based on servo signals read from the servo tracks by the reading heads disposed at opposite ends of the set of reading heads. | 09-04-2008 |
20080239553 | STORAGE APPARATUS AND HEAD POSITION DEMODULATING APPARATUS - A servo pattern demodulating system for a storage apparatus includes a processing unit which calculates an outer product and an inner product of first and second vector information items read from a servo pattern recorded on a recording medium. The processing unit calculates a tangent value of an angular difference by a division between a value of the outer product and a value of the inner product, and converts a tangent value into track position information in conformity with an approximate formula and a difference table. In the difference table, each difference between the track position information corresponding to a tangent value and a value of the approximate formula is stored. The processing unit adds up the track position information based on the approximate formula and the difference, thereby to demodulate the position offset magnitude of the head. | 10-02-2008 |
20090002872 | METHOD AND APPARATUS FOR POSITIONING HEAD ON DATA TRACK WITH A VARIABLE TRACK WIDTH IN A DISK DRIVE - According to one embodiment, there is provided a disk drive has a controller that performs positioning control of a head on a data track with a variable track width. The disk drive has a disk in which concentric servo tracks are configured at regular intervals and in which the positions of the individual servo tracks and servo data including position information that enables a position in the range of a servo track width to be detected in units of a specific minimum offset are recorded. The controller performs positioning control of the head on a data track with a variable track width on the basis of the servo track. | 01-01-2009 |
20090027801 | DIFFERENTIAL TIMING BASED SERVO PATTERN FOR MAGNETIC-BASED STORAGE MEDIA - A magnetic storage media includes a magnetic first-pole polarity initialized servo track segment and a magnetic second-pole polarity differential timing based servo pattern recorded on the magnetic first-pole polarity initialized servo track segment. The magnetic second-pole polarity differential timing based servo pattern represents magnetic encoded servo position information for facilitating a determination of a servo position error signal exclusive of noise. | 01-29-2009 |
20090040651 | DISC APPARATUS AND METHOD OF STORING SERVO INFORMATION ON DISC MEDIUM - According to an aspect of an embodiment, a disc apparatus includes a medium being capable of storing data and including a plurality of sets of servo information, each set of the servo information having identification information, a head for writing data into and reading data from the medium, an actuator for supporting the head and a controller for controlling the actuator in reference to selected one of the sets of the servo information on the basis of the associated identification information so as to move the head to a target position of the medium. | 02-12-2009 |
20090059419 | DATA STORAGE DEVICE - According to an aspect of an embodiment, an apparatus, includes: a medium having inner and outer edges and including first and second servo regions extending radially, and containing first and second servo information written thereon, respectively, the first servo region extending outwardly from the inner edge to cover tracks, the first and second servo region having positioned adjacently across a circular boundary; a head for reading out said first servo information and said second servo information; and a processor for executing a process comprising: reading out the first or second servo information; and when controlling the track position across the boundary, adjusting the relation of the first and second servo information across the boundary in control the track position. | 03-05-2009 |
20090086362 | Recording disk and disk drive - Embodiments of the present invention provide a recording disk capable of curtailing the amount of servo data to be stored thereon, and a disk drive. According to one embodiment, servo data area sets each of a first servo data area and plural second servo data areas arranged in that order in a read direction HR are arranged successively on each of tracks of a magnetic disk. Stored in a second sector data section included in the second servo data area is data representing a distance in the read direction HR from the position of the first servo data area to that of the same second servo data area. The amount of data stored in the second sector data section is less than that of data stored in a first sector data section included in the first servo data area. | 04-02-2009 |
20090097155 | MAGNETIC MEDIA HAVING A SERVO TRACK WRITTEN WITH A PATTERNED MAGNETIC RECORDING HEAD - A thin film magnetic recording head utilizing a timing based servo pattern is fabricated using a focused ion beam (FIB). The recording head is fabricated by sputtering a magnetically permeable thin film onto a substrate. A gap pattern, preferably a timing based pattern, is defined on the thin film and the FIB cuts a gap through the thin film based on that pattern. Once completed, the recording head is used to write a servo track onto magnetic tape. The timing based servo track then allows for the precise alignment of data read heads based on the positional information obtained by a servo read head which scans the continuously variable servo track. | 04-16-2009 |
20090147397 | PATTERNED MAGNETIC RECORDING MEDIUM AND METHOD OF RECORDING TRACK INFORMATION ONTO THE SAME - Provided are a patterned magnetic recording medium and a method of recording track information onto the patterned magnetic recording medium. The patterned magnetic recording medium includes: a data sector comprising a plurality of magnetic recording regions which are spaced apart from one another, wherein the magnetic recording regions constitute a plurality of tracks which are each shaped like a ring; and a servo sector comprising servo patterned regions and correction code regions, which are each provided on each of the plurality of tracks, wherein information regarding a track that is to be actually used in a hard disk drive (HDD) is recorded on a correction code region of at least one track of the plurality of tracks. | 06-11-2009 |
20090154004 | Servo architecture for high areal density data storage - A track accessing mechanism includes a track accessing arm actuable by a primary actuation device for accessing concentric data tracks on a storage medium and at least one slider attached to the track accessing arm. The at least one slider includes a servo head configured to read positional information from a plurality of continuous, concentric rings radially spaced apart from each other on a storage medium and a data head configured to read and write user data to the least one concentric data track. At least a portion of each ring includes servo information. The at least one data track is positioned between each continuous, concentric ring on the storage medium. | 06-18-2009 |
20090219647 | Dielectrophoretic Tweezers Apparatus and Methods - Dielectrophoretic (DEP) tweezers apparatus and methods for various applications, including particle trapping. Two electrodes are disposed on or otherwise constitute an elongated object forming a tip. A voltage is applied across these electrodes to produce a non-uniform electromagnetic field proximate to the tip thereby creating a dielectrophoretic trap. Once trapped, a particle may be moved to desired locations via manipulation of the elongated object or the medium in which the particle is located. Multiple DEP tweezers apparatus may be arranged to form arrays of tips capable of respectively generating local electromagnetic fields confined to the tips. Such DEP arrays may be employed in nanofabrication processes involving nanolithography or nano-manipulation, as well as data storage and retrieval applications. | 09-03-2009 |
20090310248 | THIN-FILM MAGNETIC HEAD WITH VARIABLE-VOLUME CAVITY IN MEDIUM-OPPOSED SURFACE - Provided is a thin-film magnetic head in which the magnetic spacing can be appropriately controlled by dynamically and accordingly, by adjusting the pressure working between the thin-film magnetic head and the magnetic recording medium according to the change of conditions such as the change over time. The thin-film magnetic head comprises at least one cavity for adjusting a pressure working between the thin-film magnetic head and the magnetic recording medium, provided in a surface of the head opposed to the magnetic recording medium, and a volume of the at least one cavity being variable. When the magnetic recording medium passes through near the cavity, the cavity generates a (negative) pressure that attracts the head and the medium toward each other. The amount of the negative pressure depends on the volume of the cavity; thus, a magnetic spacing d | 12-17-2009 |
20100085659 | Information storage devices using magnetic domain wall motion - An information storage device includes a magnetic track and a pinning element for pinning the magnetic domain wall. The magnetic track includes a plurality of magnetic domains and a magnetic domain wall arranged between each pair of adjacent magnetic domains. The pinning element is configured to apply a magnetic field to pin the magnetic domain wall to the magnetic track. The magnetic field may have the same magnetization direction as the magnetic domain wall. | 04-08-2010 |
20100149682 | DYNAMIC PITCH AND ROLL SENSING IN HARD DISK DRIVES - A head for a hard disk drive that includes a primary read element and a first sensor read element coupled to a head body. The first sensor read element is offset from the primary read element. The first sensor read element provides a read signal that can be analyzed to determine a pitch of the head. The head may also have a second sensor read element that is offset from the first sensor read element. The second sensor read element provides a read signal that can also be analyzed to determine a pitch of the head. Read signals of the first and second sensor read elements can be analyzed to determine a roll of the head. | 06-17-2010 |
20100232055 | Information storage devices and methods of operating the same - An information storage device includes a magnetic structure having a buffer track and a plurality of storage tracks connected to the buffer track. A write/read unit is disposed on the magnetic structure, and a plurality of switching devices are respectively connected to the buffer track, the plurality of storage tracks, and the write/read unit. The switching devices that are respectively connected to the buffer track and the storage tracks. The information storage device further includes a circuit configured to supply current to at least one of the magnetic structure and the write/read unit. | 09-16-2010 |
20120019956 | ADJUSTING A TRANSDUCER HEAD FOR TRANSFERRING DATA - A transducer head apparatus ( | 01-26-2012 |
20120307400 | DISK STORAGE APPARATUS, DISK CONTROL APPARATUS AND WRITE CONTROL METHOD - According to one embodiment, a disk storage apparatus includes a write module and a controller. The write module is configured to move a write head over a disk, and to perform the shingled write method, recording data in the first track while erasing data from a part of the second, i.e., adjacent track. The controller is configured to acquire a first head positioning error with respect to the first track and a second head positioning error with respect to the second track. If the first head positioning error exceeds an off-track threshold value, indicating that the data may no longer be maintained in the first and second tracks, the controller inhibits the data writing. | 12-06-2012 |