1
Ron J Kadlec, Christopher J Turner, Charles R Watt, Hans B Wach: Calibration storage methods for a digital focus and tracking servo system with calibration. DPHI Acquisitions, Jonathan W Hallman, MacPherson Kwok Chen & Heid, March 27, 2007: US07196979 (20 worldwide citation)

A method of storing calibrated optical parameters is presented. In some embodiments, calibrated optical parameters are stored in place of stored parameters. In some embodiments, averages between the calibrated operating parameters and stored optical parameters are stored. In other embodiments, the s ...


2
Ron J Kadlec, Charles R Watt, Christopher J Turner, Hans B Wach: Digital focus and tracking servo system. DPHI Acquisitions, MacPherson Kwok Chen & Heid, October 26, 2004: US06809995 (15 worldwide citation)

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, a ...


3
Ron J Kadlec, Charles R Watt, Christopher J Turner: Digital servo system with biased feed-forward. DPHI Acquisitions, Jonathan Hallman, MacPherson Kwok Chen & Heid, March 28, 2006: US07020054 (12 worldwide citation)

A digital servo system with a biased feed-forward control is disclosed. The biased feed-forward control determines the low frequency component of a control signal from the digital servo system. The low frequency component can then be added to a future control signal to form an adjusted control signa ...


4
Ron J Kadlec, Christopher J Turner, Hans B Wach: Tracking and focus servo system with error signal inverse non-linearity calibration. DPHI Acquisitions, Jon Hallman MacPherson Kwok Chen & Heid, November 15, 2005: US06965547 (12 worldwide citation)

A digital servo system of an optical disk drive with a calibrated inverse non-linearity function is disclosed. A look-up table is determined, for example, with a focus error signal gain corresponding with a focus error signal offset so that the response of the focus servo system is substantially lin ...


5
Ron J Kadlec, Charles R Watt, Christopher J Turner: Calibration of a focus sum threshold in a focus servo system. DPHI Acquisitions, MacPherson Kwok Chen & Heid, November 2, 2004: US06813226 (11 worldwide citation)

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 p ...


6
Ron J Kadlec, Hans B Wach, Christopher J Turner: Calibration of focus error signal offset in a focus servo system. DPHI Acquisitions, Jonathan W Hallman, MacPherson Kwok Chen & Heid, August 15, 2006: US07092322 (10 worldwide citation)

A focus error signal offset calibration is presented. The focus error signal offset can be calibrated by varying the focus error signal offset to optimize an operating characteristic of the optical disk drive. In some embodiments, the operating characteristic can be a servo function. In some embodim ...


7
Kelly J Beavers, Michael A Blatchley, David L Detro, Christopher J Turner, Thomas E Zaczek: Variable speed recording method and apparatus for a magnetic tape drive. Ecrix Corporation, Jessica Clement, October 23, 2001: US06307701 (9 worldwide citation)

A method and apparatus for varying track recording speed to maximize host-to-tape data transfer rates is presented. Variable data transfer rates of host systems and networks are accommodated by continually adjusting the tape speed to match the tape drive to the host's actual transfer rate. The ...


8
Ron J Kadlec, Charles R Watt, Hans B Wach, Christopher J Turner: Calibration of tracking error signal gain in a tracking servo system. DPHI Acquisitions, MacPherson Kwok Chen & Heid, Jon W Hallman, June 14, 2005: US06906985 (9 worldwide citation)

A calibration for a tracking error signal gain in a tracking servo system of an optical disk drive is presented. The calibration determines the peak-to-peak tracking error signal when the tracking servo system is open, calculates a gain factor in response to the peak-to-peak tracking error signal, a ...


9
Ron J Kadlec, Charles R Watt, Christopher J Turner, Hans B Wach: Calibration initiation methods for a tracking and focus servo system. DPHI Acquisitions, Jon Hallman, MacPherson Kwok Chen & Held, April 4, 2006: US07023776 (9 worldwide citation)

A calibration method for an optical disk drive is presented. The operating parameters of an optical disk drive are initially calibrated when the disk drive is produced or during a repair step. The disk drive is then field calibrated during normal operation. Operating parameters can be field calibrat ...


10
Ron J Kadlec, Christopher J Turner: Tracking and focus servo system with a media type boundary crossing detector. DPHI Acquisitions, MacPherson Kwok Chen & Heid, April 27, 2004: US06728182 (8 worldwide citation)

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 ...