Abstract: A tilt adjustment control method for a near-field optical system is provided. The method includes the following steps. A gap between a lens and a disc is detected. A gain corresponding to the gap is provided. A tilt signal is detected. A tilt compensation value according to the tilt signal and the gain is obtained. A tilt adjustment control is performed on the lens according to the tilt compensation value.

Abstract: A radially expandable multiple tubular member apparatus includes a first tubular member and a second tubular member engaged with the first tubular member forming a joint. A sleeve overlaps and couples the first and second tubular members at the joint.

Abstract: A method is described for detecting a mechanical shock in a disc drive apparatus (1) of a type comprising: scanning means (30) for scanning record tracks of a disc (2) and for generating a read signal (SR); actuator means (50) for controlling the positioning of at least one read/write element (34) of said scanning means; a control circuit (90) for receiving said read signal (SR), deriving at least one error signal (RE) from said read signal, and generating at least one actuator control signal (SCR) on the basis of said error signal. The method comprises the steps of: -determining a shock sensitivity function (SSHOCK) which describes the relationship between shocks (OExT) and said error signal; determining or at least approximating an inverse shock sensitivity function (S-lSHOCK) as the inverse of said shock sensitivity function (SSHOCK);—and applying said inverse shock sensitivity function (Sl-SHOCK)on said error signal.

Abstract: A disk drive comprising a tray (TR) for receiving a disk, the tray (TR) being supported for movement between a first position within a casing (CS) of the disk drive and a second position projecting from the casing (CS), an electric motor for moving the tray (TR) between the first and second positions, and regulation means for regulating an electric current through the motor for regulating the rotation of the motor. The regulation means comprises detection means for detecting a back-electromotive voltage produced during rotation of the motor for deriving position information of the tray (TR) with respect to the first and second positions.

Abstract: The apparatus comprises an emulator 62, which emulates the functions of the actuator 20, which moves the optical system used for the processing of data on the data carrier. By this measure the defects that the carrier may comprise provides less disturbance for the user. Application: the invention is well suited for optical discs containing some defects.

Abstract: An apparatus for scanning a track on a record carrier has a head (22) and front end circuitry (31) for scanning the track and generating scanning signals. A detection unit (32) detects anomalies in the scanning signal, for example for adjusting a tracking servo. The detection unit (32) calculates a mean value of the scanning signal and compares the mean value to a threshold for providing an anomaly detection signal (33). Further a classification unit (34) provides an indication of the type of defect for determining a suitable responsive or corrective action.

Abstract: An optical disk drive (50) comprises a radial servo system (70) for driving the position of an optical head (52) for scanning an optical disk (10) comprising at least one recording track (11; 12, 13), a focus servo system (80) for controlling the focussing of an optical beam, and a data retrieval system (90) for regenerating the digital data recorded on disk. Operative parameters of the radial servo system (70) and/or focus servo system (80) and/or data retrieval system (90) are frozen or are set to predetermined values as soon as the optical head (52) reaches a predetermined location (17) along a current track (12; 13) which is determined on the basis of a defect entry location (17) along a previous track (11; 12).