Abstract: A servo system with a multi-track seek algorithm with an track zero crossing period integrity test is presented. Zero crossing periods for subsequent cycles can be determined from a tracking error signal. If the zero crossing period for a first cycle differs substantially from the zero crossing period for a second cycle, then an error can be indicated. In some embodiments, the first cycle and the second cycle are subsequent cycles. In some embodiments, the zero crossing period in the second cycle can be between half and twice the zero crossing period in the first cycle. In some embodiments, other ranges are utilized. For example, in some embodiments the zero crossing period in the second cycle can be between one quarter and four times the zero crossing period in the first cycle.

Abstract: A disk drive includes a housing, a cartridge tray, and a cam plate. The cartridge tray is adapted to hold a cartridge that includes a data storage disk. The housing has a pair of vertical cartridge tray pin slots which hold tray pins that are part of the cartridge tray. The cam plate includes a pair of cam slots formed at an oblique angle to the cartridge tray pin slots. The tray pins extend through the cam slots into the cartridge tray pin slots. Movement of the cam plate back and forth causes the tray pins and cartridge tray to move vertically between a loaded position, where data can be read from or written to the data storage disk, to an unloaded position. The use of two cartridge tray pins allows the cartridge tray to rotate about an axis defined by the tray pins, and this action assists in locating the cartridge precisely in a repeatable position, in contact with a plurality of datums, when it is fully loaded.

Abstract: Disclosed is a method for aligning a rotating device such as an actuator assembly to a base of, for example, a disk drive. The device is rotatably mounted to the base about the pivot pin. The method may involve adjusting the angular position of the pivot pin relative to the base unless or until the actuator assembly rotates in a first plane parallel to a second plane containing a surface of the data storage disk. In one embodiment, the data storage disk is mounted for rotation on a disk rotation motor. The disk rotation motor, in turn, is mounted to a base. With the device positioned between the base and the data storage disk, the device is rotated about the pivot pin. While the device is rotated about the pivot pin, electrical current is provided to the device. The magnitude of the electrical current is proportional or inversely proportional to a distance D separating the device from the data storage disk. The electrical current is monitored as the device rotates about the pivot pin.

Abstract: A file system for accessing information on digital storage media is provided by a storage device controller embedded within the storage device. The storage device controller includes an interface component to receive a packet having a file system command. A command decode component in the storage device controller decodes the file system command, and an interface response structure component creates a strategy for performing the file system command. The storage device controller generates an identifier for a file system object and accesses the file system object using the file system object's identifier. A host system coupled to the storage device receives a storage device access request from an application program and generates a command to perform on the file system object based on the storage device access request. The host system uses the identifier to indicate the file system object to be accessed.

Abstract: A hub assembly for a data storage disk including a hub member and a raised boss near a center axis of the hub member, the raised boss being surrounded by an annular bonding surface and being configured so as to protrude into a center hole of a data storage disk when the bonding surface is in contact with a surface of the disk.

Abstract: A determination of a focus sum threshold in a tracking and focus servo system of an optical disk drive is presented. The focus sum threshold can be determined by moving an optical pick-up unit sinusoidally through a focus position, for example by moving the optical pick-up unit between its closest position to an optical media and its farthest position from the optical media. While moving the optical pick-up unit, a sum signal is monitored. In some embodiments, the sum signal is the sum of signals from a plurality of detectors in the optical pick-up unit. The focus sum threshold is set to a fraction of a peak value of the sum signal.

Abstract: A direction sensor in a tracking and focus servo system of an optical disk drive is presented. The direction sensor calculates a direction sum signal and a tracking error signal from side elements of detectors in an optical pick-up unit of the optical disk drive. A first direction can be indicates when the signs of a high-pass filtered sum signal and a high pass filtered tracking error signal are opposite and a second direction opposite the first direction if the signs are the same.

Abstract: A first-surface optical disk including features, such as a slot defined on an edge of the housing for providing clearance for a blocking tab in a drawer mechanism so as to allow the cartridge assembly to be fully inserted into the drawer mechanism when the shutter member is in the second position.

Abstract: A digital servo system for controlling tracking or focus in an optical disk driver is presented. A servo system according to the present invention includes an optical pick-up with detectors providing optical signals, an analog processor receiving the optical signals and providing a digital signal, and digital processors receiving the digital signal and providing a control signal that controls the position of the optical pick-up unit. The digital processor executes an algorithm that calculates an error signal, provides amplification and biasing to the error signal, provides filtering for the error signal, and computes the control signal. The error signal can be the focus error signal or the tracking error signal.

Abstract: A servo system with a multi-track seek algorithm is presented. The multi-track seek algorithm detects zero crossings in a tracking error signal, counts the number of zero crossings to form a count, and calculates a reference velocity from the count. The algorithm also determines a time period between successive zero crossings, calculates a velocity from the time period, calculates a difference signal between the reference velocity and the velocity, and adjusts the control signal so that the velocity follows the reference velocity. The reference velocity can follow a velocity profile with acceleration portions, coasting portions, and deceleration portions which move an optical pick-up unit from a starting position to a target position.

Abstract: A servo system with a multi-track seek algorithm with an accelerated servo function for regaining a closed tracking loop is presented. Upon completion of a multi-track seek operation, a gain of a tracking servo system is increased for a predetermined number of cycles. In some embodiments, the increased gain leads to a more aggressive track closing operation.

Abstract: A system and method for controlling operation of a motor system that addresses the design challenges for the small form factor optical disk system. The control system can be operable to detect a first BEMF crossing and setting a first time stamp, to detect a second BEMF crossing and setting a second time stamp, to calculate a measured spin period as the difference between the first time stamp and the second time stamp, to compare the measured spin period to a reference spin period to determine a period error, to operate on the period error with a proportional gain and an integrator gain to provide a command output; and to drive a winding in the spin motor with a current to cause the spin motor to change velocity in response to the command output.

Abstract: A system, method, and apparatus for coordinating tasks in a control system for an optical disc drive for optical media with a pitted premastered area that cannot be overwritten and a grooved user-writeable area that can be overwritten. The optical disc drive includes a first processor operable to communicate with a second processor, wherein the first processor includes instructions for performing non-time-critical tasks, and the second processor includes instructions for performing time-critical tasks, such as reading from and writing to optical media in the disc drive. The first processor monitors the status of the time critical tasks in the second processor and transmits commands to perform operations in the second processor. The first processor also controls power mode, manages recovery from errors, controls focus, tracking/seeking, spin, physical sector address (PSA), a laser, adjusts gains, and monitor cartridge load/eject.

Abstract: A data storage disk includes a writeable area that allows a user to write data, wherein the data files are written from the outside diameter towards the inside diameter of the writeable area, while file system information is written from the inside diameter towards the outside diameter of the writeable area. This optimizes the use of the writeable area, whether a large number of small data files or a small number of large data files are being stored. To further optimize the use of the writeable area, information may be stored in two or more different error correction code (ECC) block sizes. Thus, information, such as the file system attributes and linking sectors, which contains few bytes may be stored in the smaller ECC block size, while the data may be stored in the larger ECC block size. The data storage disk, may also include a mastered content area.

Abstract: A method of changing the position of a component controlled by a servo system is disclosed. In accordance with the disclosed invention, the current position and the current control signal corresponding to the current position is determined. A target control signal corresponding to a target position is also determined. A smooth control signal profile is then calculated between the current control signal and the target control signal. The smooth control signal is then applied to move the component form the current position to the target position. In some embodiments, the smooth control signal can be, for example, a half-period sine wave with one extreme at the current control signal and the opposite extreme at the target control signal.

Abstract: Disclosed is a data storage system having a base, a motor mounted to the base, and a device for detecting the presence of a data cartridge in the data storage system. The device is operatively coupled to the motor and generates a signal when the device detects the presence of the data cartridge in the data storage system. The motor activates in response to generation of the signal. The motor, when activated, moves the data cartridge within the data storage system between operational and non-operational positions. In one embodiment, the device includes a light sensor and a light generator. The light sensor is positioned to receive light generated by the light generator. The light sensor generates the signal in response to an interruption of the light received by the sensor. The device may further include device further an opaque shield directly or indirectly connected to the base. This shield is movable with respect to the light generator and sensor.

Abstract: A boundary crossing detector in a tracking and focus servo system of an optical disk drive is presented. A tracking error signal can be monitored as an optical pick-up unit of the optical disk drive is allowed to move across an optical media in the optical disk drive. If a peak-to-peak value of the tracking error signal changes by a threshold value, than the boundary crossing can be indicated.

Abstract: An optical pickup assembly includes an optical pickup unit (OPU), a thermally conductive plate, and a flex circuit. The flex circuit is mounted atop the plate. The OPU is also mounted atop the plate through a cutout of the flex circuit. Alternatively, the flex circuit is mounted below the plate and the OPU is mounted atop the plate. The optical pickup assembly further includes an actuator arm. The OPU is mounted on the actuator arm with a portion of the plate contacting the actuator arm.

Abstract: An optical assembly including a service loop extended from a focus section of an actuator arm. A portion of the service loop bends when a tracking section of the actuator arm rotates around a tracking axis while a portion of the flex circuit twists when the focus section of the actuator arm rotates around a focus axis.