Sampling Servo System Patents (Class 369/44.34)
  • Patent number: 10496559
    Abstract: Systems and methods are disclosed for full utilization of a data path's dynamic range. In certain embodiments, an apparatus may comprise a circuit including a first filter to digitally filter and output a first signal, a second filter to digitally filter and output a second signal, a summing node, and a first adaptation circuit. The summing node combine the first signal and the second signal to generate a combined signal at a summing node output. The first adaptation circuit may be configured to receive the combined signal, and filter the first signal and the second signal to set a dynamic amplitude range of the combined signal at the summing node output by modifying a first coefficient of the first filter and a second coefficient of the second filter based on the combined signal.
    Type: Grant
    Filed: October 10, 2017
    Date of Patent: December 3, 2019
    Assignee: Seagate Technology LLC
    Inventors: Jason Bellorado, Marcus Marrow, Zheng Wu
  • Patent number: 10241692
    Abstract: A computing device includes an interface configured to interface and communicate with a dispersed storage network (DSN), a memory that stores operational instructions, and a processing module operably coupled to the interface and memory such that the processing module, when operable within the computing device based on the operational instructions, is configured to perform various operations. For example, the computing device monitors storage unit (SU)-based write transfer rates and SU-based write failure rates associated with each of the SUs for a write request of encoded data slices (EDSs) to the SUs within the DSN. The computing device generates and maintains a SU write performance distribution based on monitoring of the SU-based write transfer rates and the SU-based write failure rates and adaptively adjusts a trimmed write threshold number of EDSs and/or a target width of EDSs for write requests of sets of EDSs to the SUs within the DSN.
    Type: Grant
    Filed: August 26, 2016
    Date of Patent: March 26, 2019
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Greg R. Dhuse, Jason K. Resch, Ethan S. Wozniak
  • Patent number: 9680461
    Abstract: In some aspects, a local oscillator includes a voltage controlled oscillator, a multi-stage frequency divider including first and second stages, and a duty-cycle converter. An output node of the voltage controlled oscillator is coupled to an input node of the first stage. An output node of the first stage is coupled to an input node of the second stage. The first stage is configured to output a first signal from one of a first plurality of signal paths, each configured to provide a signal having a distinct frequency. The second stage is configured to output a second signal from one of a second plurality of signal paths, each configured to provide a signal having a distinct frequency. An output node of the multi-stage frequency divider is coupled to an input node of the duty-cycle converter.
    Type: Grant
    Filed: March 1, 2016
    Date of Patent: June 13, 2017
    Assignee: Cognitive Systems Corp.
    Inventors: Rahul Singh, Trevor Pace, Tajinder Manku
  • Patent number: 9019804
    Abstract: Aspects of the disclosure provide a sync mark detector. The sync mark detector includes a first unit configured to decay over time a value indicating a length of a bit format, a second unit configured to compare the decayed value with a detected length of the bit format to determine a new length, and a third unit configured to detect a sync mark based on the detected length and the new length.
    Type: Grant
    Filed: January 13, 2014
    Date of Patent: April 28, 2015
    Assignee: Marvell International Ltd.
    Inventors: Mats Oberg, Jin Xie
  • Patent number: 8838033
    Abstract: Methods and systems for processing a signal with a corresponding noise profile are disclosed. Aspects of the method may comprise analyzing spectral content of the noise profile. At least one noise harmonic within the signal may be filtered based on said analyzed spectral content. The filtered signal may be amplified. The noise profile may comprise a phase noise profile. The signal may comprise at least one of a sinusoidal signal and a noise signal. At least one filter coefficient that is used to filter the at least one noise harmonic may be determined. The filtering may comprise low pass filtering. The signal may be modulated prior to filtering. The amplifying may comprise buffering. A non-linearity characteristic of the signal may be determined and a noise harmonic may be low-pass filtered within the signal based on the determined non-linearity characteristic.
    Type: Grant
    Filed: December 7, 2004
    Date of Patent: September 16, 2014
    Assignee: Broadcom Corporation
    Inventor: Shervin Moloudi
  • Patent number: 8824254
    Abstract: An optical disc device includes an optical pickup that causes a laser beam to be incident on an optical disc and detects a reflected beam, an A/D converter that converts into a digital signal a plurality of analog signals obtained from the reflected beam detected by the optical pickup, an error signal generating circuit that generates a servo signal for the optical pickup based on the digital signal converted by the A/D converter, a low-pass filter that removes noise of a specific band included in the servo error signal generated by the error signal generating circuit, a main processor that switches a noise removal band of the low-pass filter based on states of the optical disc, and an actuator that performs servo control for the optical pickup based on the servo error signal from which the noise has been removed by the low-pass filter.
    Type: Grant
    Filed: April 12, 2013
    Date of Patent: September 2, 2014
    Assignee: Funai Electric Co., Ltd.
    Inventors: Syunsuke Sehara, Shinya Shimizu
  • Patent number: 8718563
    Abstract: A method for processing a signal with a corresponding noise profile includes analyzing spectral content of the noise profile, filtering at least one noise harmonic within the signal based on the analyzed spectral content, and limiting the filtered signal. The noise profile may include a phase noise profile. The signal may include a sinusoidal signal and/or a noise signal. At least one filter coefficient that is used to filter the at least one noise harmonic may be determined. The filtering may include low pass filtering. The limiting may include hard-limiting of the filtered signal. A phase difference between the limited signal and a reference signal may be detected.
    Type: Grant
    Filed: September 6, 2011
    Date of Patent: May 6, 2014
    Assignee: Broadcom Corporation
    Inventor: Shervin Moloudi
  • Patent number: 8634284
    Abstract: A differential phase detector for an optical storage system is set forth. The differential phase detector includes a photodetector circuit arranged to detect light deviations associated with radial errors in the optical storage system. A non-linear equalizer is in communication with the photodetector circuit. The output of the non-linear equalizer is in communication with signal processing circuitry. The signal processing circuitry uses the equalized signals to generate one or more radial error signals.
    Type: Grant
    Filed: January 28, 2013
    Date of Patent: January 21, 2014
    Assignee: Marvell International Ltd.
    Inventors: Christopher Painter, Jin Xie
  • Patent number: 8599663
    Abstract: An approach is described that allows an optical disc drive to accurately verify the power level of irradiation beam power levels associated a write strategy used in high speed, high density optical disc media formats using a front monitor diode with a relatively slow rise time and/or relative slow fall time compared to the clock cycle speed of the write strategy signal. A portion of encoded data to be written to an optical disc media may be overwritten to include a predetermined data pattern. During write strategy processing of the data, the predetermined data pattern is replaced with a constant write strategy power level. The constant write strategy output placed within the write strategy signal may control the optical disc drive laser to emit a constant irradiation beam for a duration sufficiently long to allow the front monitor diode to obtain an accurate measure of the irradiation beam power level.
    Type: Grant
    Filed: October 7, 2008
    Date of Patent: December 3, 2013
    Assignee: Marvell International Ltd.
    Inventor: Tom Geukens
  • Patent number: 8520133
    Abstract: An imaging apparatus that adjusts focus based on frequency components extracted from an image signal is provided. The apparatus includes a 1st order Infinite Impulse Response (IIR)-filter including a plurality of sample delayers having a plurality of line buffers for buffering and delaying a plurality of samples to sequentially read pixels of the image signal through raster scanning and extracting frequency components of the image signal from the read pixels by using the plurality of sample delayers; and a delay sample number controller for controlling the IIR-filter to match the number of horizontal pixels sequentially read from the image signal through raster scanning to the number of the plurality of samples buffered by the plurality of line buffers.
    Type: Grant
    Filed: December 20, 2011
    Date of Patent: August 27, 2013
    Assignee: Samsung Electronics Co., Ltd
    Inventor: Naofumi Wada
  • Patent number: 8466644
    Abstract: First and second A/D converters perform analog/digital conversion of first and second signals of a Hall signal so as to generate third and fourth signals as digital signals. A differential conversion circuit generates a fifth signal as a single-ended signal that corresponds to the difference between the third and fourth signals. An offset correction circuit corrects offset of the fifth signal so as to generate a sixth signal. An amplitude control circuit stabilizes the amplitude of the sixth signal to a predetermined target value, and generates its absolute value, thus generating a seventh signal. A control signal generating unit generates a control signal based upon the seventh signal. A driver circuit drives a motor according to the control signal.
    Type: Grant
    Filed: March 24, 2011
    Date of Patent: June 18, 2013
    Assignee: Rohm Co., Ltd.
    Inventors: Tatsuro Shimizu, Hiroyuki Ishii, Nobuo Komura, Toshiya Suzuki
  • Patent number: 8462602
    Abstract: A data recovery device including an analog to digital converter (ADC), a filtering-equalizing unit, a zero crossing detector, a data phase locked loop, a data mapping unit and an estimation unit is provided. The ADC converts a radio frequency signal to a plurality of sampling data points. The sampling data points are converted to a plurality of retiming data points and a clock signal by the filtering-equalizing unit, the zero crossing detector and the data phase locked loop. The data mapping unit selects a plurality of maximum data points and minimum data points from the returning data points, and determines whether to map the maximum data points and the minimum data points to other levels for partially reconstructing the retiming data points. The estimation unit recovers the reconstructed retiming data points to a modulation signal.
    Type: Grant
    Filed: March 4, 2011
    Date of Patent: June 11, 2013
    Assignee: Sunplus Technology Co., Ltd.
    Inventors: Shih-Hsien Liu, Zhieng-Chung Chen
  • Patent number: 8427914
    Abstract: A lens pull-in method is used in a near-field optical accessing system. When a lens is in a far-field range, the lens is driven to approach a surface of an optical disc in an open loop control state. If the lens enters a near-field range, a first GES level is inputted as a set value and the lens is driven in a close loop control state. When the gap error signal decreases to the first GES level, the set value is changed to a second GES level, which is higher than the first GES level. When the gap error signal increases to the first GES level, the set value is changed to a target GES level, so that the gap error signal is maintained at the target gap error signal.
    Type: Grant
    Filed: January 5, 2011
    Date of Patent: April 23, 2013
    Assignee: Lite-On It Corp.
    Inventor: Tung-Hsu Hsieh
  • Publication number: 20130028063
    Abstract: The amplitude deviation of a tracking error signal in an optical disk apparatus is reliably corrected by processing signals at low costs. A servo signal generator generates a tracking error signal and a lens error signal from a photodetected signal. A lens error deviation signal memory circuit stores the lens error signal generated at the servo signal generator, and reproduces the one-turn deviation of the lens error signal. A tracking error signal corrector learns an amplitude correcting value for the tracking error signal from the tracking error signal detected in reproducing the one-turn deviation of the lens error signal, and stores the amplitude correcting value in a correcting signal generator.
    Type: Application
    Filed: July 26, 2012
    Publication date: January 31, 2013
    Inventor: Fumio ISSHIKI
  • Patent number: 8363517
    Abstract: A differential phase detector for an optical storage system is set forth. The differential phase detector includes a photodetector circuit arranged to detect light deviations associated with radial errors in the optical storage system. A non-linear equalizer is in communication with the photodetector circuit. The output of the non-linear equalizer is in communication with signal processing circuitry. The signal processing circuitry uses the equalized signals to generate one or more radial error signals.
    Type: Grant
    Filed: January 24, 2012
    Date of Patent: January 29, 2013
    Assignee: Marvell International Ltd.
    Inventors: Christopher Painter, Jin Xie
  • Patent number: 8351311
    Abstract: The present invention achieves higher precision and lower power consumption by reducing semiconductor chip occupation area. A semiconductor integrated circuit which can be mounted on an optical disk device has: a wobble signal generating circuit capable of receiving first, second, third, and fourth light reception output signals A, B, C, and D of a light receiving element in an optical pickup and detecting a wobble in a recordable disk; a differential phase detection signal (DPD) generating circuit for tracking an unrecordable disk; and two A/D converters and an arithmetic circuit.
    Type: Grant
    Filed: April 26, 2011
    Date of Patent: January 8, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Toshiya Matsuda, Hiroshi Ide
  • Patent number: 8320230
    Abstract: A processing circuit for optical data is provided. The processing circuit includes a signal-processing module and a radio frequency (RF) signal-summing module. The signal-processing module averages and filters the data signals to obtain a low-frequency signal. The RF signal-summing module receives the data signals and the low-frequency signal, sums the data signals to obtain a summed data signal, and subtracts the low-frequency signal from the summed data signal to obtain a RF summing signal.
    Type: Grant
    Filed: March 27, 2008
    Date of Patent: November 27, 2012
    Assignee: Mediatek Inc.
    Inventors: Chih-Chien Huang, Chien Ming Chen, Kuo-Pin Lan
  • Patent number: 8203918
    Abstract: A low pass filter unit generates a slice level for digitizing the signal based on the track state from the signal. When a tracking servo is in invalid state, a sample hold unit holds a slice level sampled at a predetermined timing. A comparison unit compares the signal based on the track state to the slice level and generates a mirror signal. When the tracking servo becomes in an invalid from valid state, the low pass filter unit uses the slice level held in the sample hold unit.
    Type: Grant
    Filed: May 15, 2006
    Date of Patent: June 19, 2012
    Assignee: Rohm Co., Ltd.
    Inventor: Shiro Eshita
  • Publication number: 20120134252
    Abstract: A method of generating a 1-beam tracking error signal (TES), an optical pickup device, and an optical disc drive device adopting the method. A light-receiving element receives a single reflection beam and detects an alternating current (AC) component and a direct current (DC) component from each of areas formed on two sides of a data track. A servo unit generates a TES by adding and subtracting the AC component and the DC component.
    Type: Application
    Filed: November 17, 2011
    Publication date: May 31, 2012
    Inventors: Ui-yol Kim, Yong-jae Lee
  • Patent number: 8189433
    Abstract: Disclosed herein are an optical recording medium driving device and an additional recording method, which performs tracking servo control for moving an objective lens in a direction orthogonal to a tangential direction of a guide track so that a guide tracking error signal is decreased with respect to a guide track of a guide layer separation type recording medium, detects an additional recording start position subsequent to a recorded track if the recorded track is present in a recording layer of the optical recording medium, generates a tracking correction signal according to the reproduction tracking error signal upon tracking servo control of the recorded track just before the additional recording start position, and corrects tracking servo control according to the tracking correction signal upon additional recording start.
    Type: Grant
    Filed: October 3, 2008
    Date of Patent: May 29, 2012
    Assignee: Pioneer Corporation
    Inventors: Kazuo Takahashi, Masaharu Nakano
  • Patent number: 8174949
    Abstract: Various embodiments of the present invention provide systems, methods and media formats for processing user data derived from a storage medium. As an example, a system is described that includes a storage medium with a series of data. The series of data includes a servo data and a user data region. The user data region includes a first synchronization pattern and a second synchronization pattern located a distance from the first synchronization pattern. A storage buffer is provided that is operable to receive at least a portion of the series of data. A retiming circuit calculates an initial phase offset and frequency offset for a defined bit within the storage buffer using a first location of the first synchronization pattern and a second location of the second synchronization pattern. An error correction loop circuit re-samples the series of data from the storage buffer based at least in part on the initial phase offset and a frequency offset.
    Type: Grant
    Filed: July 2, 2009
    Date of Patent: May 8, 2012
    Assignee: LSI Corporation
    Inventor: Nayak Ratnakar Aravind
  • Patent number: 8125862
    Abstract: The present techniques provide methods and systems for alignment of a read head with data tracks on an optical data disk. In embodiments, a multi-pixel detector that is segmented into multiple areas, or detector segments, may be used to detect a pattern in the light reflected from an optical data disk. The detector system may then combine the quantized values from each of the detector segments mathematically to determine the alignment of the read head with a target data track. If the read head drifts to one side or the other, detectors to the side of a center detector may start to pick up energy from the adjacent tracks. If this energy is continuously summed for the detectors on each side, the read head may be centered by balancing the sums from the detectors on each side.
    Type: Grant
    Filed: December 18, 2008
    Date of Patent: February 28, 2012
    Assignee: General Electric Company
    Inventors: John Anderson Fergus Ross, Kenneth Brakeley Welles, John Erik Hershey, Xiaolei Shi, Victor Petrovich Ostroverkhov
  • Patent number: 8116178
    Abstract: A method of operating a channel module, including: receiving a plurality of sensor signals generated based on at least one detected characteristic of a laser beam of an optical drive; performing computations based on the plurality of sensor signals; generating a computation output signal based on the computations; generating a first control signal and a second control signal; generating a first input signal based on (i) the computation output signal, (ii) the first control signal, and (iii) a first set of filter values; generating a second input signal based on (i) the second control signal, (ii) a second set of filter values, and (iii) an accumulated output signal; generating the accumulated output signal based on a sum of products generated based on the first input signal and the second input signal; and adjusting the at least one detected characteristic of the laser beam based on the accumulated output signal.
    Type: Grant
    Filed: February 8, 2011
    Date of Patent: February 14, 2012
    Assignee: Marvell International Ltd.
    Inventors: Jeff Mitchem, Chris Turner
  • Patent number: 8107329
    Abstract: A differential phase detector for an optical storage system is set forth. The differential phase detector includes a photodetector circuit arranged to detect light deviations associated with radial errors in the optical storage system. A non-linear equalizer is in communication with the photodetector circuit. The output of the non-linear equalizer is in communication with signal processing circuitry. The signal processing circuitry uses the equalized signals to generate one or more radial error signals.
    Type: Grant
    Filed: July 7, 2008
    Date of Patent: January 31, 2012
    Assignee: Marvell International Ltd.
    Inventors: Christopher Painter, Jin Xie
  • Patent number: 8093845
    Abstract: The present invention discloses a 3-phase brushless DC motor controller, which comprises: a unit for generating a PWM signal; an ADC for converting a back electromotive force (BEMF) signal from an analog form into a digital form; a synchronization and extraction unit operating in synchronization in part with the PWM signal for extracting the digital BEMF signal to obtain a corresponding ZCP signal; and a unit for judging whether a commutation operation is to be performed according to a change of the corresponding ZCP signal. A wait instruction and a delay instruction help to accurately acquire the digital BEMF signal.
    Type: Grant
    Filed: January 12, 2010
    Date of Patent: January 10, 2012
    Assignee: Padauk Technology Co., Ltd.
    Inventor: Mao-Hsin Cheng
  • Patent number: 8081543
    Abstract: An optical disc apparatus according to the present invention steadily performs a focus jump operation and a track-crossing seek operation relative to an optical disc having a plurality of recording layers. A signal processing section generates a focus error signal based on a conventional astigmatism detection (CAD) system and a focus error signal based on a differential astigmatism detection (DAD) system from a detection signal generated by an optical detector. When a focus jump is to be performed from one recording layer of the optical disc to another recording layer, a focus drive signal that is generated from the focus error signal based on the CAD system is used. When a read/write operation is to be performed in relation to one recording layer, a focus drive signal that is generated from the focus error signal based on the DAD system is used.
    Type: Grant
    Filed: August 24, 2007
    Date of Patent: December 20, 2011
    Assignee: Hitachi-LG Data Storage, Inc.
    Inventor: Takeshi Imai
  • Patent number: 8068404
    Abstract: A signal apparatus is provided. The signal value holding apparatus including a determining section to determine a magnitude relationship between a signal value of an input signal and a signal value of a prescribed feedback signal, a first holding section to hold the signal value determined to be larger by the determining section, a subtracting section to subtract a prescribed value from the signal value held by the first holding section and output a result as the feedback signal, and a second holding section to receive the signal value held by the first holding section and hold the signal value supplied from the first holding section when the signal value of the input signal becomes smaller than the signal value of the feedback signal based on a determination result of the magnitude relationship between the signal values by the determining section.
    Type: Grant
    Filed: January 5, 2009
    Date of Patent: November 29, 2011
    Assignee: Sony Corporation
    Inventor: Yuji Gendai
  • Patent number: 8054725
    Abstract: An optical disk apparatus for writing signals on a recording medium by irradiating the recording medium with a laser beam modulated based on the signals includes a first converting unit for converting a first reflected laser beam component from the recording medium into electrical signals; a second converting unit for converting a second reflected laser beam component into electrical signals; a first sample-and-hold unit for sampling and holding the electrical signals from the first converting unit; a second sample-and-hold unit for sampling and holding the electrical signals from the second converting unit; and transmitting devices for transmitting the held signals from the first and the second sample-and-hold units. The sampled signals are averaged, and the averaged signal is held in each of the first and the second sample-and-hold units during signal writing.
    Type: Grant
    Filed: October 15, 2004
    Date of Patent: November 8, 2011
    Assignee: Sony Corporation
    Inventors: Toru Nagara, Yoshio Fukutomi
  • Patent number: 8054723
    Abstract: Disclosed is a method and apparatus for controlling the record and reproduction of optical record medium in which plural nonrecord regions having different phase are arranged between recordable data regions for the distinction in the shape of the data region. The method and apparatus performs the servo using focus error signal and tracking error signal averaged by the low pass filter at the header region of the optical disc. Especially, the tracking servo is performed by holding a fixed DC off-set value at the header region existing on the L/G switching or holding the tracking error value of the previous same track region. As a result, the exact header region is detected, the track sliding phenomenon is removed, and the tracking servo is stabilized, resulting in preventing the degeneration of the record and reproduction characteristics.
    Type: Grant
    Filed: March 2, 2009
    Date of Patent: November 8, 2011
    Assignee: Ionosep X Holdings L.L.C.
    Inventors: Sang On Park, Seong Pyo Hong
  • Publication number: 20110261662
    Abstract: A lens pull-in method is used in a near-field optical accessing system. When a lens is in a far-field range, the lens is driven to approach a surface of an optical disc in an open loop control state. If the lens enters a near-field range, a first GES level is inputted as a set value and the lens is driven in a close loop control state. When the gap error signal decreases to the first GES level, the set value is changed to a second GES level, which is higher than the first GES level. When the gap error signal increases to the first GES level, the set value is changed to a target GES level, so that the gap error signal is maintained at the target gap error signal.
    Type: Application
    Filed: January 5, 2011
    Publication date: October 27, 2011
    Applicant: LITE-ON IT CORP.
    Inventor: Tung-Hsu Hsieh
  • Patent number: 8014724
    Abstract: Methods and systems for processing a signal with a corresponding noise profile are disclosed. Aspects of the method may comprise analyzing spectral content of the noise profile. At least one noise harmonic within the signal may be filtered based on said analyzed spectral content. The filtered signal may be limited. The noise profile may comprise a phase noise profile. The signal may comprise at least one of a sinusoidal signal and a noise signal. At least one filter coefficient that is used to filter said at least one noise harmonic may be determined. The filtering may comprise low pass filtering and the limiting may comprise hard-limiting the filtered signal. The signal may be modulated prior to the filtering. The signal may be downconverted prior to the modulating. At least one signal component of the signal may be downconverted.
    Type: Grant
    Filed: October 1, 2004
    Date of Patent: September 6, 2011
    Inventor: Shervin Moloudi
  • Publication number: 20110211431
    Abstract: The present invention enables a comprehensive evaluation from both of data read from a disk and a servo signal of a servo controller. The present invention provides a semiconductor integrated circuit mountable to a disk recording and reproducing drive, which comprises a signal processor of an RF signal read from a pickup, a servo controller responsive to a servo error signal read from the pickup, a memory controller, and an external interface. The memory controller is supplied with read data and a servo signal and stores the read data and the servo signal in a buffer memory according to a time division process. The read data and the servo signal stored in the buffer memory can be transferred to an external device via the external interface by the memory controller.
    Type: Application
    Filed: February 25, 2011
    Publication date: September 1, 2011
    Inventors: Norihiko NAKANO, Hajime ISHIHARA, Akio FUKUSHIMA
  • Patent number: 8000186
    Abstract: A method for enhancing the optical initializing operation comprises: sending a radial error signal from an optical pick-up unit to a radial error signal calibration unit; sending the radial error signal from the optical pick-up unit to an offset adjuster; sending a calibrated radial error signal from the radial error signal calibration unit to the offset adjuster and a gain adjuster; sending a radial actuator (RA) signal from the radial error signal calibration unit to activate a radial actuator during an initialization or a period for calculating RE signal calibrating parameters.
    Type: Grant
    Filed: June 29, 2009
    Date of Patent: August 16, 2011
    Assignee: Philips & Lite-On Digital Solutions Corporation
    Inventor: Marcel Rieck
  • Patent number: 7995449
    Abstract: A system of sampling interface for an optical pick-up head comprises an optical pick-up head, a PMOS, a boost circuit, and a sample and hold circuit. The optical pick-up head outputs one of a reading voltage and a writing voltage. The PMOS gate receives the gate voltage and then the PMOS is turned on to pass the reading voltage to the sample and hold circuit. Moreover, the substrate of the PMOS receives a control voltage. The boost circuit is used to boost the gate voltage higher than the control voltage for turning off the PMOS and isolating the writing voltage.
    Type: Grant
    Filed: December 21, 2009
    Date of Patent: August 9, 2011
    Assignee: Tian Holdings, LLC
    Inventor: Chih-Min Liu
  • Patent number: 7995430
    Abstract: Provided is an optical disk device capable of recording and/or reproducing information on optical disks with high reliability; and a method for controlling the optical disk device. The position of an optical lens where the amplitude of a reproduction signal during the period corresponding to a minimum-length recording mark and a space having the same length reaches its maximum is detected; and the detected position is set as a reference position for the objective lens relative to the optical disk, for use in focus control. Also, the position of the objective lens where the result of multiplication of resolution and modulation becomes greatest is detected; and the detected position is set as a reference position for the objective lens relative to the optical disk, for use in focus control.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: August 9, 2011
    Assignee: Hitachi-LG Data Storage, Inc.
    Inventors: Tsuyoshi Toda, Toshiki Ishii
  • Publication number: 20110188358
    Abstract: Disclosed herein are an optical recording medium driving device and an additional recording method, which performs tracking servo control for moving an objective lens in a direction orthogonal to a tangential direction of a guide track so that a guide tracking error signal is decreased with respect to a guide track of a guide layer separation type recording medium, detects an additional recording start position subsequent to a recorded track if the recorded track is present in a recording layer of the optical recording medium, generates a tracking correction signal according to the reproduction tracking error signal upon tracking servo control of the recorded track just before the additional recording start position, and corrects tracking servo control according to the tracking correction signal upon additional recording start.
    Type: Application
    Filed: October 3, 2008
    Publication date: August 4, 2011
    Applicant: PIONEER CORPORATION
    Inventors: Kazuo Takahashi, Masaharu Nakano
  • Publication number: 20110170387
    Abstract: An optical disc apparatus and a control method for the optical disc apparatus are provided. A control method for an optical disc apparatus according to one embodiment of the present invention may comprise rotating a disc through a spindle motor if a type of a disc loaded in the optical disc apparatus is determined; and carrying out servo operation which can be processed irrespective of rotation speed of the disc while checking whether the rotation speed of the disc equals a predetermined speed. Servo operation which can be processed independently of the rotation speed of the disc can correspond to operation related to focusing servo and additionally to operation related to tracking servo. Therefore, since the time the user has to wait for requested video, music, or data to be extracted after the user has inserted a medium is reduced, user convenience can be improved.
    Type: Application
    Filed: January 10, 2011
    Publication date: July 14, 2011
    Inventors: Cheol JIN, Donghyeong SEONG
  • Patent number: 7974160
    Abstract: A gain calibration method for optical storage servo systems in which, plant gain calibration is used by injecting a reference sine wave r into an optical storage servo system, obtaining an effort signal m at the input of the servo plant and an error signal y at the output of the servo plant, using a DFT (Discrete Fourier Transformation) to translate the time domain signals m and y into frequency responses M and Y, calculating a Y-to-M ratio, and using the magnitude of the Y-to-M ratio as the plant gain K of the servo system. The servo system's sensor gain K1 at the outermost layer of a disk may be calibrated by, e.g., the conventional peak-to-peak measurement. Since K=K1┬ĚK2, the servo system's actuator gain K2 at the outermost layer of the disk may be obtained. Because the actuator gain K2 is the same for all layers of a disk, the variation of the sensor gain K1 at an inner layer may follow that of the plant gain K at that layer.
    Type: Grant
    Filed: August 15, 2008
    Date of Patent: July 5, 2011
    Assignee: Marvell International Ltd.
    Inventors: Yuan Zheng, Alex Chiang, Enya Cheng
  • Patent number: 7969831
    Abstract: A method of controlling a servo in an optical disc device and a servo control device using the method, in which the servo control device controls a servo for printing on a label surface of an optical disc and includes an optical pickup unit, an error signal generation unit, and a control unit. The optical pickup unit outputs a plurality of signals corresponding to a position of an object lens in response to light reflected from the label surface. The error signal generation unit outputs an error signal by selecting or combining one or more of the plurality of signals. The control unit adjusts the position of the object lens in response to the error signal. Therefore, because the position of the object lens can be adjusted with an increased range, the spot size of a beam condensed by the object lens can be adjusted within an increased range, and a data recording time can be reduced. Moreover, data retention characteristics and recording quality can be improved.
    Type: Grant
    Filed: September 5, 2008
    Date of Patent: June 28, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Soo-yong Kim
  • Patent number: 7957234
    Abstract: An optical pickup apparatus comprising: a laser diode; an objective lens configured to focus laser light emitted from the laser diode on a signal recording layer of an optical disc; a first aberration correction element arranged in an optical path between the laser diode and the objective lens; and a second aberration correction element arranged in the optical path between the laser diode and the objective lens and having an aberration correction speed lower than the aberration correction speed of the first aberration correction element, the first aberration correction element and the second aberration correction element being selectively operated according to the required aberration correction speed.
    Type: Grant
    Filed: February 20, 2009
    Date of Patent: June 7, 2011
    Assignees: Sanyo Electric Co., Ltd., Sanyo Optec Design Co., Ltd.
    Inventors: Tohru Hotta, Ryoichi Kawasaki
  • Patent number: 7924664
    Abstract: Disclosed herein is a technology that enables stable and high-speed writing and/or reading in an optical disk apparatus. The optical disk apparatus has an optical head that includes a first circuit for driving a laser diode, a second circuit for sampling and holding analog electric signals that are based on reflected laser light from the optical disk, and a third circuit for converting said signals being sampled and held into digital signals. Signals digitized in the optical head are transmitted to the apparatus body side using time-division multiplexing. The first circuit, the second circuit, and the third circuit are constructed on a single substrate or in a single IC.
    Type: Grant
    Filed: March 5, 2004
    Date of Patent: April 12, 2011
    Assignee: Hitachi-LG Data Storage, Inc.
    Inventor: Toshimitsu Kaku
  • Patent number: 7911909
    Abstract: A jitter counter according to the present invention is connected to a PLL circuit for generating a clock signal, which is necessary for signal processing, from a binary signal, and counts jitters of the binary signal.
    Type: Grant
    Filed: October 14, 2008
    Date of Patent: March 22, 2011
    Assignee: Rohm Co., Ltd.
    Inventor: Takahiro Nishiyama
  • Patent number: 7885151
    Abstract: A servo accelerator for an optical drive includes input and output (I/O) terminals that receive an input signal from a processor of the optical drive. An error circuit generates an error signal based on a sensed characteristic of a laser beam. A compensation circuit generates a compensation signal based on the input signal and the error signal. A servo output adjusts the sensed characteristic of the laser beam based on the compensation signal.
    Type: Grant
    Filed: November 15, 2007
    Date of Patent: February 8, 2011
    Assignee: Marvell International Ltd.
    Inventors: Jeff Mitchem, Chris Turner
  • Patent number: 7869324
    Abstract: A method for identifying a type of an optical disk includes the steps of: turning on a laser diode of an optical pickup and focusing light emitted from the laser diode on the optical disk; moving the optical pickup to obtain a plurality of servo signals; reading a specific servo signal from the servo signals; and determining the type of the optical disk according to the count of enabled times of the specific servo signal and a corresponding enabled time period.
    Type: Grant
    Filed: June 17, 2008
    Date of Patent: January 11, 2011
    Assignee: Sunplus Technology Co., Ltd.
    Inventors: Jung-Huang Huang, Chia-Ming Chang
  • Patent number: 7870463
    Abstract: A DSP of a DVD recorder includes: a gain setting portion determining appropriate values of a first gain ? and a second gain ? when playback of an optical disc is performed, recording the first gain ? and the second gain ? thus determined in a gain storing portion, and setting them in a main differential amplifier and a sub differential amplifier, respectively; and a correction performing portion reading, when recording on the optical disc is performed, the first gain ? and the second gain ? stored in the gain storing portion, correcting at least one of them, and setting them in the main differential amplifier and the sub differential amplifier, respectively.
    Type: Grant
    Filed: October 20, 2008
    Date of Patent: January 11, 2011
    Assignee: Funai Electric Co., Ltd.
    Inventors: Shunsuke Sehara, Yasunori Kuwayama
  • Patent number: 7859954
    Abstract: An optical disk apparatus is constructed for writing or reading information by irradiating a laser beam onto an optical disk while rotating the optical disk under a focus control of the laser beam relative to the rotated optical disk. In the optical disk apparatus, an irradiating section is operated to irradiate a laser beam onto the optical disk. A determining section determines a process pattern of the focus control by operating the irradiating section to irradiate the laser beam onto a predetermined area of the optical disk and by monitoring the laser beam reflected back from the predetermined area. A focusing section performs the focus control to regulate a spot diameter of the laser beam based on the determined process pattern during either of the writing or reading of information.
    Type: Grant
    Filed: July 14, 2008
    Date of Patent: December 28, 2010
    Assignee: Yamaha Corporation
    Inventor: Morito Morishima
  • Patent number: 7848189
    Abstract: It is an optical disk apparatus that comprises: a laser drive device for outputting a test power larger than a prescribed value in a gap section; an optical pickup for forming a beam spot on a disk and detecting reflected light; a focus error detector for detecting position shift between a recording face of the information recording medium and the beam spot; a focus control device for controlling the position shift; and a focus drive device for driving an objective lens in directions far from and close to the disk, wherein, in the gap section, the focus drive device keeps a focus drive output level of right before the laser drive device outputs the test power, and sets a recording power such that the emitted light power becomes the prescribed value.
    Type: Grant
    Filed: November 13, 2006
    Date of Patent: December 7, 2010
    Assignee: Panasonic Corporation
    Inventor: Masaya Kuwahara
  • Patent number: 7843775
    Abstract: An optical disc apparatus and a focusing method for the same prevent a focusing start error of an optical pickup when using a ring-shaped lens to handle multiple wavelengths, and allow the optical pickup to start focusing at the correct starting time. To write and/or read data to and/or from an optical disc, an optical pickup in the optical disc apparatus emits a laser beam to the disc through an objective lens, and reads a reflected beam to output a read signal. The optical pickup outputs a signal based on the read reflected beam. An actuator controls the position of the objective lens so that the laser beam is focused on a surface of the disc. A focusing controller performs focusing operations on the actuator using a focus error signal generated from the signal outputted from the optical pickup. A focusing start time detector processes the read signal used to generate the focus error signal and detects when to start the focusing control of the focusing controller.
    Type: Grant
    Filed: April 12, 2007
    Date of Patent: November 30, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sang Yeal Park, Kab Kyun Jeong, Kwan Joon Kim
  • Patent number: 7839735
    Abstract: Herein disclosed a phase difference detection apparatus for detecting a phase difference between a first signal and a second signal, which may include a waveform equalization section configured to input the first and second signals as a target waveform and an input waveform, respectively, to perform a waveform equalization process using a FIR filter so that the input waveform may coincide with the target waveform; and a phase difference detection section configured to perform a predetermined calculation based on predetermined tap coefficients of the FIR filter in the waveform equalization section to calculate an asymmetric component of the tap coefficients of the FIR filter thereby to detect the phase difference between the first and second signals.
    Type: Grant
    Filed: July 11, 2007
    Date of Patent: November 23, 2010
    Assignee: Sony Corporation
    Inventor: Junya Shiraishi
  • Patent number: 7839732
    Abstract: A system and method for calibrating a recording track offset of an optical storage device accessing an optical storage medium of land/groove type. The system includes: a tracking servo loop arranged to control tracking operations of an optical head of the optical storage device; a track offset control loop arranged to control the recording track offset for the tracking servo loop; a controller arranged to enable a latest value of the recording track offset to be a readout value for utilization in a recording process performed later; and a comparator arranged to compare a recording length with a threshold value and generate a flag to represent whether the recording length is a long recording length, wherein the latest value is derived from the track offset control loop.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: November 23, 2010
    Assignee: Mediatek Inc.
    Inventors: Kuo-Ting Hsin, Ming-Hsien Tsai