Abstract: A pixel for an ambient light and/or color sensor includes a plurality of pinned photodiodes. The pixel also includes a floating diffusion region. A ratio of an active area of the plurality of pinned photodiodes to an area of the floating diffusion region is greater than 150.

Abstract: A method for repairing at least one defective servo segment of a servo sector having at least one defective servo track written on a magnetic recording media. The method comprises mapping the magnetic recording media for locations of the defective servo segment of the servo sector. A non-defective segment of the servo sector is replicated at least once on the magnetic recording media in a customer data zone, thereby creating at least one good servo segment copy of the servo sector. The good servo segment copy is propagated through the customer data zone associated with the defective servo segment. The good servo segment copy is copied onto the magnetic recording media previously occupied by the defective servo segment of the servo sector.

Abstract: A method for repairing at least one defective servo segment of a servo sector having at least one defective servo track written on a magnetic recording media. The method comprises mapping the magnetic recording media for locations of the defective servo segment of the servo sector. A non-defective segment of the servo sector is replicated at least once on the magnetic recording media in a customer data zone, thereby creating at least one good servo segment copy of the servo sector. The good servo segment copy is propagated through the customer data zone associated with the defective servo segment. The good servo segment copy is copied onto the magnetic recording media previously occupied by the defective servo segment of the servo sector.

Abstract: A self-servowriting (SSW) method that, with the actuator fully engaged against a compliant structure (e.g., a crashstop), first writes a tightly-spaced open-loop sequence of servo bursts in a segmented spiral path and then continues writing this tightly-spaced sequence under closed-loop servo control while reading back amplitude information from the servo bursts written earlier until the tightly-spaced burst pattern extends over several read-write head (RWH) offset intervals. With the actuator still engaged against the compliant structure, this tightly-spaced startup sequence is then read back by the closed servo control loop to write a number of concentric servo seed tracks, which are then self-propagated across the remainder of the disk surface to produce a final servopattern.

Abstract: A self-servowriting (SSW) method that, with the actuator fully engaged against a compliant structure (e.g., a crashstop), first writes a tightly-spaced open-loop sequence of servo bursts in a segmented spiral path and then continues writing this tightly-spaced sequence under closed-loop servo control while reading back amplitude information from the servo bursts written earlier until the tightly-spaced burst pattern extends over several read-write head (RWH) offset intervals. With the actuator still engaged against the compliant structure, this tightly-spaced startup sequence is then read back by the closed servo control loop to write a number of concentric servo seed tracks, which are then self-propagated across the remainder of the disk surface to produce a final servopattern.

Abstract: A servo system for displacing a head relative to a disk of a hard disk drive. The servo system comprises a dual-stage actuator, a calibration signal generator, and a calibration factor generator. The calibration signal generator generates a calibration signal having a calibration portion. The calibration factor generator generates a calibration factor. The servo system operates in operating and calibration servo modes. In the operating mode, the system defines first and second servo loops. The calibration factor is used as one of the parameters of the second servo loop. In the calibration servo mode, the calibration signal forms the second control signal, and the calibration factor generator generates the calibration factor based on movement of the head before any substantial response of the third servo loop to the calibration portion.

Abstract: A polycarbonate electrolyte comprising a polycarbonate membrane matrix and a lithium salt-containing electrolytic solution impregnated into the polycarbonate membrane matrix.

Abstract: The present invention is a method and apparatus for generating a skew or position offset signal for aligning the read element of an MR head with the centerline of written data, during a read operation. The disk has a plurality of tracks, one of which contains a calibration burst that allow the read element to be centered with the centerline of written data. This is accomplished by first writing the calibration burst on a predetermined number of sectors of the track. A profile of the calibration burst is obtained by micro-jogging the head from a first position that is -50% from the track centerline to a second position that is +50% of the track centerline, and sensing the magnitude of the calibration burst in various increments between the first and the second positions. For each microjogging position, the magnitude of the calibration burst is obtained. The microjogging position corresponding to the peak value of the calibration burst represents the offset between the read and the write elements.

Abstract: The present invention is a method and apparatus for generating a skew or position offset signal for aligning the read element of an magneto-resistive (MR) head with the centerline of written data, during a read operation. The disk has a plurality of tracks each of which are divided into sectors. Two adjacent tracks are first erased and a calibration burst is written in the odd sectors, for example, the first and third sectors of one of the tracks. A calibration burst is also written in the even sectors, such as the second and fourth sectors of the adjacent track. Without adjusting the position of the MR head, the value of the calibration burst on the latter track is read. Since the read element is offset from the write element, it can read the values of the calibration bursts on the odd sectors of one track and the values of the calibration bursts on the even sectors of the other track. The average values of calibration bursts, E.sub.oddave and E.sub.evenave are obtained. An offset value corresponding to E.

Abstract: The present invention is a method and apparatus for rewriting servo information on a disk of a hard disk drive. The new servo pattern is written on the tracks on the heads or sides of a disk pack using the stagger wedge scheme. When the read/write heads reach the first track beyond the inner diameter crash stop of the disk pack, the first read/write head is directed to write the new servo information, followed by the writing of data in each sector of the entire track, while the other read/write heads remain deactivated. The data writes over any pre-existing servo information on the track. Next, the second read/write head is directed to write the new servo information, followed by the writing of data in each sector of a complete track while the other read/write heads are deactivated. During the power-on sequence, the read/write heads are directed to the portions of the disk beyond the inner diameter crash stop, where the new servo pattern and the new data have been written, so as to read the new servo pattern.

Abstract: A method and apparatus for storing position offset information not used for aligning the read element of an MR head with the centerline of written data, during a read operation. The skew or offset between the read and the write elements on a read head is first calibrated. The offset information then stored on one or more dedicated tracks of the disk. To accomplish this, the write element is aligned with the centerline of the dedicated track. The position offset information is then written in the data field of the dedicated track. During the power-on process, the read element is aligned with the centerline of the dedicated track and the position offset information may be retrieved by simply reading the information previously stored on the dedicated track.

Abstract: A method and apparatus for generating servo information used in positioning the read head of a hard disk drive. The apparatus comprises a disk having a plurality of tracks, at least one of which has a servo field which includes four servo bits: an A bit, a B bit, a C bit and a D bit, where the A bit and the B bit have a common boundary located at the track centerline and where the C bit and the D bit have a common boundary. A servo signal based on the four servo bits is generated and used to position the head relative to a track of the disk. A servo signal may be generated from the sum of the difference between the A and B bits, and the difference between the C and D bits. An offset may be used to eliminate phase errors introduced into the servo signal. The offset may be representative of the magnitude of the difference between the C and D bits. The servo signal may also be generated from the difference of the difference between the A and B bits, and the difference between the C and D bits.

Abstract: A method and apparatus for storing position offset information not used for aligning the read element of an MR head with the centerline of written data, during a read operation. The skew or offset between the read and the write elements on a read head is first calibrated. The offset information then stored on one or more dedicated tracks of the disk. To accomplish this, the write element is aligned with the centerline of the dedicated track. The position offset information is then written in the data field of the dedicated track. During the power-on process, the read element is aligned with the centerline of the dedicated track and the position offset information may be retrieved by simply reading the information previously stored on the dedicated track.