Patent application number | Description | Published |
20090040652 | MAGNETIC RECORDING DISK AND DISK DRIVE WITH PATTERNED PHASE-TYPE SERVO FIELDS FOR READ/WRITE HEAD POSITIONING - A magnetic recording disk drive uses a disk having pre-patterned servo sectors extending generally radially across the data tracks. The servo sectors include at least two position error signal (PES) bursts or fields. The phases of the PES fields in the servo readback signal are demodulated to generate a PES to control the disk drive actuator for positioning the read/write heads. Each field contains generally radially directed magnetized stripes, with each stripe comprising a plurality of islands forming a zigzag pattern. The stripes have alternating polarity of magnetizations in the along-the-track direction. In one implementation there are four fields: a first pair of fields A and B wherein the zigzag pattern of the radial stripes in field A is the mirror image about a radial line of the zigzag pattern of the radial stripes in field B, and a second like pair of fields C and D, but wherein the radial stripes in fields C and D are shifted radially by one-half the island radial height from the radial stripes in fields A and B. | 02-12-2009 |
20090046385 | MAGNETIC RECORDING DISK AND DISK DRIVE WITH AMPLITUDE-TYPE SERVO FIELDS HAVING PATTERNED ALTERNATING-POLARITY SERVO ISLANDS FOR READ/WRITE HEAD POSITIONING - A magnetic recording disk drive has a disk with pre-patterned nondata servo sectors extending generally radially across the data tracks for use in positioning the read/write heads on the data tracks. The servo sectors include a synchronization pattern of generally radially directed magnetized marks, a first field of generally radially directed magnetized stripes, and a second field of generally radially directed magnetized stripes. Each stripe in each of the two fields comprises a plurality of radially spaced discrete islands, each island having a radial height of approximately Tp, where Tp is the spacing of the track centerlines in the radial direction. In the first field, the islands are centered at a track centerline, and in the second field the islands are centered at the midline between two adjacent track centerlines. The marks and islands are discrete magnetized regions separated by nonmagnetic spaces. The marks in the synchronization pattern and the stripes in the two fields have alternating polarity of magnetizations in the along-the-track direction. | 02-19-2009 |
20090097156 | MAGNETIC RECORDING DISK AND DISK DRIVE WITH PATTERNED PHASE-TYPE SERVO FIELDS FOR READ/WRITE HEAD POSITIONING - A magnetic recording disk drive uses a disk having pre-patterned servo sectors extending generally radially across the data tracks. The servo sectors include at least two position error signal (PES) bursts or fields. The phases of the PES fields in the servo readback signal are demodulated to generate a PES to control the disk drive actuator for positioning the read/write heads. Each field contains generally radially directed magnetized stripes, with each stripe comprising a plurality of discrete radially-spaced generally parallelogram-shaped islands, each island having its length oriented at an acute angle relative to a track centerline. The stripes have alternating polarity of magnetizations in the along-the-track direction. In one implementation there are four fields: a first pair of fields A and B wherein the pattern of the radial stripes in field A is the mirror image about a radial line of the pattern of the radial stripes in field B, and a second like pair of fields C and D, but wherein the radial stripes in fields C and D are shifted radially from the radial stripes in fields A and B. | 04-16-2009 |
20090097160 | MAGNETIC RECORDING DISK AND DISK DRIVE WITH AMPLITUDE-TYPE SERVO FIELDS HAVING PATTERNED SERVO ISLANDS FOR READ/WRITE HEAD POSITIONING - A magnetic recording disk drive has a disk with pre-patterned nondata servo sectors extending generally radially across the data tracks. The disk may be a patterned-media disk with both pre-patterned data islands and pre-patterned nondata servo sectors. The servo sectors include a synchronization pattern of generally radially directed discrete magnetized marks, and first and second position error signal (PES) fields of generally radially directed discrete magnetized stripes. Each stripe in each of the two fields comprises a plurality of radially spaced discrete servo islands, each island having a radial height of approximately Tp, where Tp is the radial spacing of the track centerlines. In each field, the servo islands in alternating stripes in the along-the-track direction are shifted radially by approximately Tp. In the first PES field, the islands are centered at the midline between two adjacent track centerlines, and in the second PES field the islands are centered at a track centerline. All of the servo islands in the two PES fields have the same magnetization direction. | 04-16-2009 |
20090161246 | Random Number Generation Using Hard Disk Drive Information - A hard disk drive enhances random number generation. In particular embodiments, the hard disk drive includes a controller, a hard disk, and a head. The head includes a read sensor for reading patterns on the hard disk. The controller generates a random number based on information associated with the position of the head relative to at least one track of the hard disk. | 06-25-2009 |
20100172048 | Servo patterns for patterned media - Servo patterns for patterned media. The servo pattern includes specification of cylinder/track ID with and without a Gray code. The servo pattern space is minimized by the optimum usage of the islands. This is achieved by island allocation rules to take advantage of non-magnetic island. The island allocation also provides for easier lift-off. Logic is used to encode and decode the Gray code. Further, the Gray code is designed to stabilize the magnetic island/non-magnetic island ratio to allow for easier manufacture. | 07-08-2010 |
20120149433 | SMART PHONE DISPLAY AND KEYBOARD EXTENSION - A device for providing an external display and keypad for a smart-phone. The device has a port for receiving the smart phone. The device does not have its own computing power, but uses the computing power of the smart phone itself, thereby allowing the device to be smaller, lighter and less expensive than a standard lap-top computer not notebook device. The device is configured with a port for receiving a smart-phone and preferably holds the smart phone so that does not extend above the surface of the device or is flush with the surface of the device. The device can also be configured to allow the smart phone itself to act as a numerical keypad adjacent to the keypad provided on the device. | 06-14-2012 |
20130100550 | IMPLEMENTING MAGNETIC DEFECT CLASSIFICATION USING PHASE MODULATION - A method, apparatus, and system are provided for implementing magnetic defect classification using phase modulation for hard disk drives. A magnetic media readback signal of a hard disk drive is processed to identify predefined phase modulation (PM) characteristics to implement magnetic defect classification of magnetic media bump and pit defects. | 04-25-2013 |
20130335841 | IMPLEMENTING COMBINED PHASE AND AMPLITUDE MAGNETIC DEFECT DETECTION ON-THE-FLY - A method, apparatus, and system are provided for implementing magnetic defect location detection on-the-fly for hard disk drives. A magnetic media readback signal of a hard disk drive is demodulated to generate phase modulation (PM) and amplitude modulation (AM) signals. A new coordinate plane defined by a combined phase modulation (PM) and amplitude modulation (AM) phasor-defect detector calculation function used to locate magnetic defects on-the-fly. | 12-19-2013 |
20140320995 | IMPLEMENTING DATA FREQUENCY AND DATA BITS PER SECTOR (BPS) CALIBRATION FOR NON-CIRCULAR DISK TRACKS - A method, apparatus and a data storage device are provided for implementing data frequency and data bits per sector (BPS) calibration for data written on a recordable surface including non-circular disk tracks of a storage device. A sector based BPS profile is created for data sectors on the recordable surface. The sector based BPS profile is used for modifying a number of data clock cycles based upon longer or shorter data sectors; and data clock frequency is dynamically adjusted based upon velocity jitter. | 10-30-2014 |