Abstract: A method and system for obtaining focus optimization in an optical disc system is disclosed. The focus offset of a recording unit is set to a first of a plurality of predetermined values. A HF quality value is measured and stored for the selected focus offset value of the recording unit. The focus offset is then set to a best-known focus offset value. Tracks on the optical media being read are then jumped. The above steps are then repeated for each of the plurality of predetermined focus offset values. The optimal focus setting is then determined from the stored HF quality measurements.

Abstract: The invention relates to a method of writing data to a disc (OD). The method comprised: a) performing a plurality of writing actions in which a plurality of data portions are written to the disc, b) performing a plurality of verification actions in which written data portions are at least partly verified and at least part of the data portions are replaced if needed. The method further comprises a2) performing a decision action for each writing action in which a decision whether or not to perform the verification action for a specific written data portion is taken.

Abstract: The invention relates to a method of writing data to a disc (OD). The method comprised: a) performing a plurality of writing actions in which a plurality of data portions are written to the disc, b) performing a plurality of verification actions in which written data portions are at least partly verified and at least part of the data portions are replaced if needed. The method further comprises a2) performing a decision action for each writing action in which a decision whether or not to perform the verification action for a specific written data portion is taken.

Abstract: The invention relates to a method of writing data to a disc (OD). The method comprised: a) performing a plurality of writing actions in which a plurality of data portions are written to the disc, b) performing a plurality of verification actions in which written data portions are at least partly verified and at least part of the data portions are replaced if needed. The method further comprises a2) performing a decision action for each writing action in which a decision whether or not to perform the verification action for a specific written data portion is taken.

Abstract: A method of determining a disk type of an optical disk is provided to comprise steps of: using a first light path for forming an incident beam; moving an objective lens system corresponding to the first light path from a start position towards the optical disk; receiving a sensor output signal during the movement of the objective lens system, wherein the sensor output signal includes a central aperture signal; determining the disk type of the optical disk according to the central aperture signal.

Abstract: The invention relates to an optical data system comprising an optical disc drive and a host. The optical disc drive is arranged to receive an optical disc and perform read and write actions with respect to the optical disc. The host is arranged to instruct the optical disc drive to perform a read or write action with respect to the optical disc. The optical disc drive may be arranged to a) the optical disc drive is arranged to perform a quality measurement generating a plurality of quality parameters, b) the optical disc drive is arranged to output the plurality of quality parameters to the host, and c) the host is arranged to decide on a further action based on the received plurality of quality parameters.

Abstract: The invention relates to a method of writing data to a disc (OD). The method comprising a) performing a writing action in which a first data portion is written to the disc; a2) deciding to perform b) or not and b) verifying at least part of the first data portion that is written to the disc and deciding to replace the first data portion that is written to the disc or not. Finally the method comprises c) performing a further writing action in which a second data portion is written to the disc.

Abstract: In a tracking control method for use in an optical disk drive to read/write an optical disk, an open-loop tracking control operation of the optical disk drive is first performed according to an input tracking error signal and a predetermined periodical offset to generate a dynamic offset. Afterwards, a closed-loop tracking control operation of the optical disk drive is performed according to the input tracking error signal calibrated with the dynamic offset.

Abstract: The present invention relates to a method for operating an optical drive system capable of reproducing/recording information from/to an optical carrier (30), wherein a position error and a speed error of a radiation spot (12, 53) on the carrier has been created due to an unreliable error signal which has been generated due to a surface defect (52). The method includes the steps of registering values of e.g. servo signals, determining the occurrence of a defect using a defect detector DEFO (22), generating a first and a second compensation signal and applying these compensation signals to the control system (10) of the optical drive system. The first compensation signal is capable of reducing the speed error and the second compensation signal is capable of reducing the position error. Thus, the application of the compensation signals immediately after the unreliable error signals reduces the position error and the speed error of the focussed radiation spot (12, 53).

Abstract: A method and system for obtaining focus optimization in an optical disc system is disclosed. The focus offset of a recording unit is set to a first of a plurality of predetermined values. A HF quality value is measured and stored for the selected focus offset value of the recording unit. The focus offset is then set to a best-known focus offset value. Tracks on the optical media being read are then jumped. The above steps are then repeated for each of the plurality of predetermined focus offset values. The optimal focus setting is then determined from the stored HF quality measurements.

Abstract: An optical disk drive for determining a disk type associated with a substrate thickness of an optical disk comprising a substrate is provided to comprise a source to generate a beam, an optical arrangement arranged to direct the beam to the optical disk for forming an incident beam, a sensor arranged to sense a reflected beam and to produce a sensor output signal, a focus system comprising an objective lens system and a focus controller, wherein the objective lens system is arranged to focus the incident beam into a spot, and the focus controller is arranged to generate a focus control signal to drive and position the objective lens system; and a controller arranged to cooperate with the focus controller for moving the objective lens system, to receive the central aperture signal during the movement of the objective lens system, to analyze the central aperture signal for determining the focus actuator position, and to determine the disk type associated with the substrate thickness.

Abstract: The invention relates to a method of writing data to a disc (OD). The method comprised: a) performing a plurality of writing actions in which a plurality of data portions are written to the disc, b) performing a plurality of verification actions in which written data portions are at least partly verified and at least part of the data portions are replaced if needed. The method further comprises a2) performing a decision action for each writing action in which a decision whether or not to perform the verification action for a specific written data portion is taken.

Abstract: The invention relates to a method of writing data to a disc (OD). The method comprising a) performing a writing action in which a first data portion is written to the disc; a2) deciding to perform b) or not and b) verifying at least part of the first data portion that is written to the disc and deciding to replace the first data portion that is written to the disc or not. Finally the method comprises c) performing a further writing action in which a second data portion is written to the disc.

Abstract: The present invention discloses a method for controlling the position of a radiation beam on an optical carrier (1), e.g. a CD, a DVD, a HD-DVD or a BD disc, in an optical drive. Initially, the optical pickup unit (OPU) is fixated relative to the optical carrier and there is established a closed-loop control—so-called capture—in response to an error signal e.g. radial or focus error tracking signal (FE, RE). Then, by servo control means (9, 50) a first bandwidth (BW1) is set in a stabilization period (SP), and subsequently a second bandwidth (B W2) of the servo control means is set. The second bandwidth (B W2) is lower than the first bandwidth (BW1). The invention applies bandwidth switching and thereby provides a more robust operation of the optical drive, as the first and second bandwidths may be separately optimised. Additionally, the power consumption of the optical pickup unit (OPU) may be reduced.

Abstract: A method for restoring focusing of a laser beam on a track of an optical disc for reading or writing data from/to the track when the focusing of said beam onto said track has been lost, wherein two categories, A and B, of focus lost causes are defined, A being due to an external shock and B due to other reasons and wherein a focus re-capture is performed with the use of focus control information stored in a memory only for a category B focus lost.

Abstract: The invention provides an optical disc drive and a method for controlling a moving part, e.g. a disc tray or an optical pick-up unit, of such an optical disc drive. The method comprises, upon a start-up command being received, reading a reliability register, e.g. one bit, indicating whether stored data relating to the position of the moving part are reliable. In case the reliability register indicates that that stored data relating to the position of the moving part are un-reliable, then a blind homing is performed, and data relating to the position of the moving part are then stored in a memory. Preferably, a controlled homing action is performed after receipt of a stop command. An optical disc drive according the invention comprises a moving part (MP), a motor (MTR), e.g.

Abstract: In a tracking control method for use in an optical disk drive to read/write an optical disk, an open-loop tracking control operation of the optical disk drive is first performed according to an input tracking error signal and a predetermined periodical offset to generate a dynamic offset. Afterwards, a closed-loop tracking control operation of the optical disk drive is performed according to the input tracking error signal calibrated with the dynamic offset.

Abstract: The present invention discloses an optical apparatus capable of reproducing/recording information from/to an optical carrier, e.g. a DVD or BD disk. The apparatus has control means for positioning/focusing a radiation beam (5) on the carrier and photo detection means for detection of radiation reflected from the carrier. Additionally, defect detection means (DEFO) for detection of surface defect areas (A1, A2) can indicate where surface defects, e.g. scratches etc., are present. Processing means are adapted for integrating, and preferably differentiate, error signals (RE, FE) immediately after the beam (5.b) is exiting a defect area (A1) for generating adaptive control signals (AD_RE, AD_FE). The optical system is adapted to apply the adaptive control signals (AD_RE, AD_FE) when the beam is positioned in the defect area (A1) again, thereby reducing off-track deviation as the beam (5.d) exits the defect area (A1).

Abstract: The present invention relates to a method for operating an optical drive system capable of reproducing/recording information from/to an optical carrier (30), wherein a position error and a speed error of a radiation spot (12, 53) on the carrier has been created due to an unreliable error signal which has been generated due to a surface defect (52). The method includes the steps of registering values of e.g. servo signals, determining the occurrence of a defect using a defect detector DEFO (22), generating a first and a second compensation signal and applying these compensation signals to the control system (10) of the optical drive system. The first compensation signal is capable of reducing the speed error and the second compensation signal is capable of reducing the position error. Thus, the application of the compensation signals immediately after the unreliable error signals reduces the position error and the speed error of the focussed radiation spot (12, 53).

Abstract: An optical reading/writing apparatus has an optical head that includes a collimator and a lens. For focusing control, a startup procedure is executed to generate a first startup S-curve. A boundary is then set according to the startup S-curve. After executing focusing on and tracking on, a plurality of position combinations of the collimator and the lens are selected for focusing calibration, thereby obtaining respective focusing error signals. By comparing the focusing error signals with the boundary, whether the position combinations of the selected collimator and the lens are valid can be determined. One of the valid position combinations with the greatest image-quality value is then selected to read/write the optical disc in the subsequent reading/writing procedure.