Servo Loop Gain/switching Control Patents (Class 369/44.29)
  • Patent number: 10469103
    Abstract: Systems, devices, and methods are presented that allow a data channel to adaptively vary a change in a reference voltage used to read data from a solid state memory. The change in the reference voltage may be determined based on a measured error statistic of the solid state memory. A hard decision low density parity check (HLDPC) decoder may be utilized in conjunction with a soft decision low density parity check (SLDPC).
    Type: Grant
    Filed: April 19, 2017
    Date of Patent: November 5, 2019
    Assignee: Seagate Technology LLC
    Inventors: Seongwook Jeong, AbdelHakim Alhussien, Erich Franz Haratsch
  • Patent number: 10217480
    Abstract: Techniques for verifying a magnetic tape are disclosed. The techniques include obtaining a position signal generated by reading a magnetic tape using a stationary tape head. Next, a simulated current for adjusting a position of the tape head to follow a track on the magnetic tape is updated using the position signal. The simulated current is then compared to one or more saturation limits to generate a verification result for a servo pattern on the magnetic tape, wherein the verification result classifies the magnetic tape as usable or unusable. Finally, the verification result is outputted for use in managing subsequent use of the magnetic tape.
    Type: Grant
    Filed: February 12, 2018
    Date of Patent: February 26, 2019
    Assignee: Oracle International Corporation
    Inventor: Eduardo Raymaska Wiputra
  • Patent number: 9953671
    Abstract: Techniques for verifying a magnetic tape are disclosed. The techniques include obtaining a position signal generated by reading a magnetic tape using a stationary tape head. Next, a simulated current for adjusting a position of the tape head to follow a track on the magnetic tape is updated using the position signal. The simulated current is then compared to one or more saturation limits to generate a verification result for a servo pattern on the magnetic tape, wherein the verification result classifies the magnetic tape as usable or unusable. Finally, the verification result is outputted for use in managing subsequent use of the magnetic tape.
    Type: Grant
    Filed: July 31, 2017
    Date of Patent: April 24, 2018
    Assignee: Oracle International Corporation
    Inventor: Eduardo Raymaska Wiputra
  • Patent number: 9613657
    Abstract: The recording and reproducing apparatus according to the present disclosure includes: a light source; an optical system configured to divide a beam from the light source, and to form a first optical spot and a second optical spot on a recording medium; a recording circuit configured to drive the light source and to modulate a light amount of the light source, and further to record the information on the recording medium by the first optical spot by modulating the light amount of the light source based on information; and an evaluation circuit configured to evaluate the information recorded on the recording medium by reproducing by the second optical spot in a period in which the recording circuit causes the light source to emit the beam at a constant light amount.
    Type: Grant
    Filed: February 12, 2016
    Date of Patent: April 4, 2017
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Kazuo Momoo, Yuichi Takahashi
  • Patent number: 9336812
    Abstract: A system and method for controlling positioning of an optical pickup unit relative to at least one track of an optical data storage medium include an adaptive track position feedback controller that compensates for defocus of an optical beam relative to the optical data storage medium associated with movement across the medium and/or disturbances in distance between a lens of the optical pickup unit relative to the optical data storage medium. A track position feedback controller may include an adaptive term or parameter based on a focus (or defocus) error signal generated by a focus position feedback controller and associated sensors or detectors of a quadrature photodiode integrated circuit (PDIC).
    Type: Grant
    Filed: January 9, 2015
    Date of Patent: May 10, 2016
    Assignee: Oracle International Corporation
    Inventor: Faramarz Mahnad
  • Patent number: 9245580
    Abstract: Systems and method relating generally to data processing, and more particularly to systems and methods for utilizing multiple data streams for data recovery from a storage device.
    Type: Grant
    Filed: October 31, 2014
    Date of Patent: January 26, 2016
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: Lu Lu, Haitao Xia
  • Patent number: 9231364
    Abstract: A laser light generator emits laser light, a frequency of which can be adjusted. A laser light detector bombards an iodine cell with the laser light and photoelectrically converts the laser light that has passed through the iodine cell, then outputs a light output signal. A third order differential lock-in amplifier generates a third order differential signal of the light output signal. A frequency locker causes the laser light generator to change the frequency of the laser light within a predetermined range, detects an amplitude corresponding to a saturated absorption line occurring in the third order differential signal, and causes the frequency of the laser light to stabilize to a predetermined value. An error detector outputs an error signal in a case where the amplitude corresponding to the saturated absorption line occurring in the third order differential signal is greater than a predetermined value.
    Type: Grant
    Filed: April 28, 2014
    Date of Patent: January 5, 2016
    Assignee: MITUTOYO CORPORATION
    Inventor: Ryunosuke Yano
  • Patent number: 9087524
    Abstract: As for a quadruple light receiving unit, in a case where divided regions of A to D as in a DPD scheme is defined, when binarization signals of light reception signals in regions A to D are set as signals A to D, <1> exclusive OR between the signal A without delay and the signal B with delay, <2> exclusive OR between the signal A with delay and the signal C without delay, <3> exclusive OR between the signal B without delay and the signal D with delay, and exclusive OR between the signal B with delay and the signal D without delay are calculated, and a tracking error signal is obtained on the basis of the calculation of (<1>+<3>)?(<2>+<4>). Thus, the above problem can be solved.
    Type: Grant
    Filed: January 17, 2013
    Date of Patent: July 21, 2015
    Assignee: Sony Corporation
    Inventor: Yuuichi Suzuki
  • Patent number: 9042819
    Abstract: A wireless media player and a related system and methodology are disclosed. One aspect of the wireless media player system pertains to a virtual connector system, apparatus, and method for the automatic establishment of wireless connectivity with other electronic devices. In one embodiment, the media player device employs the use of integrated Radio Frequency Identification (RFID) technology to exchange communication settings, media capability, and other parameters with an external device that also has integrated RFID technology. The automatic exchange of settings and other information via a proximity-based RFID data exchange allows a media player to quickly establish a secure communication link with another device via a commonly supported wireless protocol such as Ultra Wideband (UWB) or Bluetooth. Another aspect of the media player system pertains to a method of using the captured media capability of the connecting device to customize certain menu options and software parameters in the media player.
    Type: Grant
    Filed: September 30, 2014
    Date of Patent: May 26, 2015
    Inventor: Robin Dua
  • Patent number: 9020429
    Abstract: A wireless media player and a related system and methodology are disclosed. One aspect of the wireless media player system pertains to a virtual connector system, apparatus, and method for the automatic establishment of wireless connectivity with other electronic devices. In one embodiment, the media player device employs the use of integrated Radio Frequency Identification (RFID) technology to exchange communication settings, media capability, and other parameters with an external device that also has integrated RFID technology. The automatic exchange of settings and other information via a proximity-based RFID data exchange allows a media player to quickly establish a secure communication link with another device via a commonly supported wireless protocol such as Ultra Wideband (UWB) or Bluetooth. Another aspect of the media player system pertains to a method of using the captured media capability of the connecting device to customize certain menu options and software parameters in the media player.
    Type: Grant
    Filed: March 6, 2014
    Date of Patent: April 28, 2015
    Inventor: Robin Dua
  • Patent number: 9014631
    Abstract: A wireless media player and a related system and methodology are disclosed. One aspect of the wireless media player system pertains to a virtual connector system, apparatus, and method for the automatic establishment of wireless connectivity with other electronic devices. In one embodiment, the media player device employs the use of integrated Radio Frequency Identification (RFID) technology to exchange communication settings, media capability, and other parameters with an external device that also has integrated RFID technology. The automatic exchange of settings and other information via a proximity-based RFID data exchange allows a media player to quickly establish a secure communication link with another device via a commonly supported wireless protocol such as Ultra Wideband (UWB) or Bluetooth. Another aspect of the media player system pertains to a method of using the captured media capability of the connecting device to customize certain menu options and software parameters in the media player.
    Type: Grant
    Filed: February 12, 2014
    Date of Patent: April 21, 2015
    Inventor: Robin Dua
  • Patent number: 8971162
    Abstract: Provided is an optical disc device including: an optical pickup which includes an objective lens and a receiver unit which receives light reflected off an optical disc; a signal processing unit which generates a main push-pull signal and sub push-pull signals from signals from the receiver unit, and obtains a signal obtained by subtracting the main push-pull signal from the sub push-pull signal multiplied K times, to generate a tracking-error signal; and a control unit which performs a midpoint servo process, an offset process of adding an offset value to a lens-error signal indicating displacement of the objective lens, a stabilization awaiting process of waiting for oscillation of the optical disc to stabilize, a measurement process of measuring the tracking-error signal, and a K value adjusting process of adjusting a value of K in response to a result of the measurement process.
    Type: Grant
    Filed: August 18, 2014
    Date of Patent: March 3, 2015
    Assignee: Funai Electric Co., Ltd.
    Inventor: Mamoru Kuwajima
  • Patent number: 8971803
    Abstract: A wireless media player and a related system and methodology are disclosed. One aspect of the wireless media player system pertains to a virtual connector system, apparatus, and method for the automatic establishment of wireless connectivity with other electronic devices. In one embodiment, the media player device employs the use of integrated Radio Frequency Identification (RFID) technology to exchange communication settings, media capability, and other parameters with an external device that also has integrated RFID technology. The automatic exchange of settings and other information via a proximity-based RFID data exchange allows a media player to quickly establish a secure communication link with another device via a commonly supported wireless protocol such as Ultra Wideband (UWB) or Bluetooth. Another aspect of the media player system pertains to a method of using the captured media capability of the connecting device to customize certain menu options and software parameters in the media player.
    Type: Grant
    Filed: August 26, 2013
    Date of Patent: March 3, 2015
    Inventor: Robin Dua
  • Patent number: 8958277
    Abstract: An optical disc device and information recording/reading method for an optical disc in which a recording layer is formed through volume recording by aligning recording tracks, which hold information, in a homogenous recording region that does not internally have a layer defining a recording position. The information recording method includes a step in which a first recording layer forming a complex recording layer is formed by forming a recording track while recording information by focusing a main beam at a predetermined depth position in the recording region, and a step in which a second recording layer forming the complex recording layer is formed by forming a recording track while recording information by focusing the main beam at a depth position that is separated from the first recording layer in a depth direction by a depth offset greater than ? of a wavelength of the main beam.
    Type: Grant
    Filed: November 1, 2011
    Date of Patent: February 17, 2015
    Assignee: Hitachi Consumer Electronics Co., Ltd.
    Inventors: Atsushi Kikugawa, Tatsuro Ide
  • Patent number: 8913469
    Abstract: An optical information storage medium system is provided. The optical information storage medium system includes an optical pickup, which comprises a photo-detector configured to control light power detected by receiving a portion of light emitted from a light source and obtains an output signal proportional to output light power of the light source from a signal detected by the photo-detector, and a signal processor configured to signal-process the output signal input from the optical pickup. The signal processor includes a sensitivity acquisition unit configured to acquire a sensitivity value of the photo-detector, a gain calculator configured to calculate a target gain value to be used in comparing the sensitivity value of the photo-detector, which is acquired by the sensitivity acquisition unit, with a target sensitivity value to be used by the optical information storage medium system, and a gain adjustment unit.
    Type: Grant
    Filed: November 4, 2011
    Date of Patent: December 16, 2014
    Assignee: Toshiba Samsung Storage Technology Korea Corporation
    Inventors: Hong-kuk Kim, Jong-hwa Yu
  • Patent number: 8874323
    Abstract: A device is described for generating a control signal for controlling a passenger protection arrangement of a motor vehicle, having a first acceleration sensor for generating a first acceleration signal, having a second acceleration sensor for generating a second acceleration signal, having a first structure-borne noise sensor for generating a first structure-borne noise signal, having a second structure-borne noise sensor for generating a second structure-borne noise signal, and having an evaluation circuit, the evaluation circuit (being configured for generating a combination signal from the first structure-borne noise signal and the second structure-borne noise signal, the evaluation circuit being configured for generating the control signal as a function of the first acceleration signal, the second acceleration signal and the combination signal.
    Type: Grant
    Filed: August 4, 2011
    Date of Patent: October 28, 2014
    Assignee: Robert Bosch GmbH
    Inventors: Nicolaus Ulbrich, Andreas Wienss
  • 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: 8824260
    Abstract: There is provided a position control apparatus including a light radiating/receiving unit that performs radiation of laser light for recording and laser light for adjacent track servo onto an optical disc recording medium through a common objective lens, and receives return light of the laser light for the adjacent track servo and the laser light for the reference surface, a tracking mechanism unit that displaces the objective lens, a reference surface tracking error signal generating unit that generates a reference surface tracking error signal, a reference surface tracking servo control unit that controls the tracking mechanism unit, a recording layer tracking error signal generating unit that generates a recording layer tracking error signal, an integrating unit that integrates the recording layer tracking error signal, an offset providing unit that provides an integration output by the integrating unit, and a feedforward control unit that generates a control signal.
    Type: Grant
    Filed: October 25, 2013
    Date of Patent: September 2, 2014
    Assignee: Sony Corporation
    Inventor: Yoshiyuki Urakawa
  • Patent number: 8780680
    Abstract: The optical disc device has a circuit which forms a focus error signal for focus servo control based on reflection light from an optical disc exposed to laser light. Also, the device has a data processing unit which can control by feedback a position to which an objective lens is moved by a focusing actuator based on a focus error signal. In label printing, the data processing unit controls, by feedforward, a position to which the objective lens is moved by the focusing actuator based on control data for label printing. The operation resolution of the focusing actuator in feedforward control is made higher than that in feedback control. Thus, an intended position control accuracy is achieved in feedforward control. For instance, in feedforward control, the gain of the driver circuit for the focusing actuator is switched to a smaller one in comparison to that in feedback control.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: July 15, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Yoshimi Iso, Mitsuo Hagiwara, Mitsuyuki Kimura
  • Patent number: 8768256
    Abstract: A wireless media player and a related system and methodology are disclosed. One aspect of the wireless media player system pertains to a virtual connector system, apparatus, and method for the automatic establishment of wireless connectivity with other electronic devices. In one embodiment, the media player device employs the use of integrated Radio Frequency Identification (RFID) technology to exchange communication settings, media capability, and other parameters with an external device that also has integrated RFID technology. The automatic exchange of settings and other information via a proximity-based RFID data exchange allows a media player to quickly establish a secure communication link with another device via a commonly supported wireless protocol such as Ultra Wideband (UWB) or Bluetooth. Another aspect of the media player system pertains to a method of using the captured media capability of the connecting device to customize certain menu options and software parameters in the media player.
    Type: Grant
    Filed: September 6, 2013
    Date of Patent: July 1, 2014
    Inventor: Robin Dua
  • Patent number: 8737181
    Abstract: Provided is an optical recording medium, including a recording target track that is a track on which small record carriers are arranged and on which information recording is performed by modulating the small record carriers through light irradiation; and a wobbling track on which the small record carriers are arranged in a wobbling manner, wherein a single wobbling track is formed to run parallel to a set of a plurality of recording target tracks.
    Type: Grant
    Filed: July 20, 2012
    Date of Patent: May 27, 2014
    Assignee: Sony Corporation
    Inventors: Yoshinori Suzuki, Kazuhiko Fujie, Koji Sekiguchi
  • Patent number: 8730774
    Abstract: An optical disk device includes an optical pickup, and a controller. The optical pickup emits light on an optical disk, and detects return light from the optical disk. The controller performs a focus control based on a focus error signal corresponding to the return light detected by the optical pickup, and performs a tracking control based on a tracking error signal corresponding to the return light detected by the optical pickup. The controller finds a relation of an amount of deviation in a tracking balance of the tracking error signal relative to a change in a focus balance of the focus error signal while the tracking control is stopped prior to reproduction of the optical disk. The controller corrects the deviation in the tracking balance attributable to the change in the focus balance based on the relation while the focus balance is adjusted.
    Type: Grant
    Filed: March 29, 2013
    Date of Patent: May 20, 2014
    Assignee: Funai Electric Co., Ltd.
    Inventor: Mamoru Kuwajima
  • Patent number: 8675463
    Abstract: An optical disc driving device includes a control circuit 4 for performing a gain adjustment for each of two recording surfaces of a multilayered optical disc 1 on the basis of an FE signal in such a way as to maintain a state in which light is focused onto either of the recording surfaces, to generate a focus servo loop signal, and for generating a focus jump signal for causing either a transition from a state in which the light is focused onto one recording surface to a state in which the light is focused onto the other recording surface, or a transition in the opposite direction from a threshold set up on the basis of an amount of gain adjustment, and a focus actuator driving circuit 5 for performing either a focus jump or an operation of maintaining the state in which the light is focused.
    Type: Grant
    Filed: December 27, 2007
    Date of Patent: March 18, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Hiroshi Hoshino, Nobuaki Hirai
  • Patent number: 8619521
    Abstract: A disc drive includes an optical pickup that emits laser light to a predetermined layer position via an objective lens and detects reflection light of the laser light, a tracking mechanism that drives the objective lens in a tracking direction, a tracking error signal generation unit that generates a tracking error signal, based on a light detecting signal for the reflection light obtained by the optical pickup, a tracking servo control unit that performs a tracking servo control based on the tracking error signal, and a control unit that makes the tracking servo control unit perform tracking servo pull-in on the basis of a frequency measurement result of the tracking error signal and a recording or non-recording determination result based on the light detecting signal.
    Type: Grant
    Filed: January 17, 2012
    Date of Patent: December 31, 2013
    Assignee: Sony Corporation
    Inventor: Yuichi Suzuki
  • Patent number: 8619525
    Abstract: An offset correction is automatically determined and routinely updated to reduce or eliminate data retrieval errors that may be caused by low level distortion in optical disc data storage recording, re-recording and retrieval system. An offset control loop is provided for reading information from a modulated wobble signal with which the data is recorded to an optical disc data storage medium to provide detection of an offset and correction of that offset to facilitate implementation of precise timing synchronization and/or encoded information contact in the system. The offset detector measures a wobble signal and mathematically converts detected information regarding the measured wobble signal to an offset correction by integrating the wobble signal over a specific time interval and comparing the integrated value to an expected integrated value. The integration may be performed over at least one period of the sinusoidal wobble signal, and the correction added to the wobble signal.
    Type: Grant
    Filed: November 13, 2012
    Date of Patent: December 31, 2013
    Assignee: Marvell International Ltd.
    Inventors: Mats Oberg, Jingfeng Liu
  • Patent number: 8619526
    Abstract: Aspects of the disclosure can provide a method for generating an offset correction signal with a reduced circuit footprint. The method can include converting samples of a wobble signal into digital values having a reduced number of bits, integrating the digital values having the reduced number of bits over a specified time interval to determine an error signal, and generating an offset correction signal based on the determined error signal.
    Type: Grant
    Filed: January 7, 2013
    Date of Patent: December 31, 2013
    Assignee: Marvell International Ltd.
    Inventor: Mats Oberg
  • Patent number: 8559282
    Abstract: An average servo control method is provided. A target level of at least a servo signal is first detected, which is corresponding to a present condition of the optical disc drive. The target level is then compared with a current level of the servo signal, and a average servo loop gain is adjusted based on the comparison result. A target level calibration may be performed before the gain adjustment. The target level calibration analyzes the servo signal to determine a plurality of preset target levels each corresponding to a different condition. The preset target levels and corresponding conditions are stored as a lookup table. In this way, the target level is acquired based on the lookup table and the present condition.
    Type: Grant
    Filed: March 20, 2008
    Date of Patent: October 15, 2013
    Assignee: Mediatek Inc.
    Inventor: Po-Wei Chang
  • Patent number: 8559285
    Abstract: An optical disc apparatus includes a focus controller including a first digital filter, tracking controller including a second filter, focus actuator driver, tracking actuator driver, defect detector for detecting a defect on an optical disc, and a system controller for controlling the focus controller, the tracking controller and the defect detector. The system controller holds an input and output of at least one of either the focus controller or the tracking controller on the basis of the output of the defect detector, and sets an initial value in a delay memory of the digital filter of the controller held upon awake of the hold state.
    Type: Grant
    Filed: August 3, 2012
    Date of Patent: October 15, 2013
    Assignee: Hitachi Consumer Electronics Co., Ltd.
    Inventor: Seiji Imagawa
  • Patent number: 8547809
    Abstract: There is a need to prevent a possible erroneous detection of an off-track condition during recording to an optical disk. The above need can be addressed by, for example, determining an off-track condition has occurred when a light spot is located at least half-way from the track being recorded toward another track adjacent the track being recorded, and stopping a recording operation. In another example, the above need can be addressed by determining that off-track has occurred based on an output of a first off-track detector which detects that the light spot is off the track based on a wobble signal, an output of a second off-track detector which detects that the light spot is off the track based on a tracking error signal, and an output of a zero-cross detector which detects that the tracking error signal crosses zero based on an output of the tracking error signal.
    Type: Grant
    Filed: June 3, 2009
    Date of Patent: October 1, 2013
    Assignee: Hitachi Consumer Electronics Co., Ltd.
    Inventors: Seiji Imagawa, Yoshinori Ishikawa
  • Patent number: 8537650
    Abstract: An optical read/write apparatus as an embodiment of the present invention includes: a light-splitting element configured to split a light beam emitted from a light source into multiple light beams including a write beam and a read beam; an optical system configured to converge the write and read beams onto the same track on an optical storage medium; a photodetector including a light receiving element configured to detect the read beam reflected from the optical storage medium and output an electrical signal; and a divider configured to generate a read signal by dividing the signal detected by the light receiving element by a signal that represents a write modulated component and that is obtained by detecting a part of the light beam emitted from the light source.
    Type: Grant
    Filed: September 11, 2012
    Date of Patent: September 17, 2013
    Assignee: Panasonic Corporation
    Inventors: Hiroshi Kayama, Kazuo Momoo
  • 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: 8514676
    Abstract: Method and device for generating a control voltage for a position actuator of a disk drive system for displacing a lens of a pick-up unit to a given X-position. The actuator is operated by an open loop control system. First, parameters of the control system are calibrated so that the control system produces a control voltage (Va) from an input position signal (Xact_setp). Then, the control voltage is processed in a feed forward system for generating a processed control signal (Va_p) which is fed to the position actuator for displacing said lens to the X-position. A Z-value corresponding to the axial distance of the lens from a calibrated axial position and a temperature of the pick-up unit are measured. The position actuator operates according to the formula: Xdc=Va—p*K(Temp,Z)/(R(Temp)*C(Temp,Z)).
    Type: Grant
    Filed: April 17, 2012
    Date of Patent: August 20, 2013
    Assignee: Koninklijke Philips N.V.
    Inventor: Cees Hezemans
  • Patent number: 8508161
    Abstract: A drive apparatus includes a magnet rotor having a plurality of magnetic poles that are magnetized, a stator having a magnetic pole portion that opposes each pole of the magnet rotor, a coil configured to excite the magnetic pole portion, a position detector configured to detect a position of the magnet rotor, a first driver configured to switch an electrification state of the coil in accordance with a preset time interval, a second driver configured to switch an electrification state of the coil in accordance with an output of the position detector, and a controller configured to select the first driver when the output of the position detector is less than a first threshold, and to select the second driver when the output of the position detector is equal to or larger than the first threshold.
    Type: Grant
    Filed: August 27, 2012
    Date of Patent: August 13, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kousuke Kiyamura, Hiromu Yasuda, Chikara Aoshima
  • Patent number: 8488424
    Abstract: Laser write parameters in an optical drive are calibrated. A parameter range for the write parameters is set based on a recordable medium, and a number of test runs are recorded on the recordable medium while varying the write parameters. Write performance characteristics over the test runs are measured. Based on the measured performance characteristics, actual write parameters are selected for use in writing actual data.
    Type: Grant
    Filed: April 26, 2012
    Date of Patent: July 16, 2013
    Assignee: Marvell International Ltd.
    Inventors: Peter Kivits, Julie Faminial, Jake Ballares, Jents Temmerman
  • Patent number: 8483024
    Abstract: Detection is made as to at least one of a ratio between a tracking error and a focus error, and a duty cycle of an off-track signal with respect to an optical disc. A decision is made as to whether or not the optical disc is playable on the basis of the detected at least one of the ratio and the duty cycle. The ratio is a ratio of the focus error to the tracking error or a ratio of the tracking error to the focus error.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: July 9, 2013
    Assignee: J & K Car Electronics Corporation
    Inventors: Takahiro Komatsu, Seiichiro Fujii, Masao Ubukata
  • Patent number: 8472290
    Abstract: A method and apparatus identifying a type of a recordable disc according to whether a land pre-pit (LPP) is formed on the disc. The apparatus includes an RF (radio frequency) amplifier amplifying light reflected by the disc to a predetermined value; an LPP signal detector detecting an LPP (Land Pre-Pit) signal from output signals of the RF amplifier; and a system controller identifying a type of the disc according to whether the LPP signal is detected by the LPP signal detector. Since a disc type is discriminated and operational conditions of a disc drive are adequately set during an early stage of a disc driving period, a lead-in time of a disc can be reduced.
    Type: Grant
    Filed: June 26, 2003
    Date of Patent: June 25, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Young-woo Lee, Sang-whook Kim
  • Patent number: 8462603
    Abstract: A three-dimensional optical memory device comprises an optical disc positioning system, two sources of radiation with wavelengths ?1 and ?2, a focusing system, an illumination system, focusing system positioning means, a spectrum splitter, an optical sensor, and a control unit. The radiation source with wavelength ?2 is an array of laser diodes, which optical axes are parallel and lie in the same plane. The illumination system comprises: a cylindrical lens positioned so that the generatrix of its cylindrical surface is parallel to the plane of the p-n junctions of the laser diodes; a focusing lens; and a stabilizing circuit comprising a beam splitter situated between the focusing lens and the cylindrical lens, a second optical sensor optically coupled to the focusing lens via the beam splitter, and a stabilizer coupled to the focusing lens, wherein the stabilizer and the second optical sensor are electrically connected to the control unit.
    Type: Grant
    Filed: March 22, 2012
    Date of Patent: June 11, 2013
    Assignee: Everhost Investments Limited
    Inventor: Vadim Veniaminovich Kiyko
  • Patent number: 8456971
    Abstract: An optical disk driving apparatus includes an optical head device having a laser light source, a converging optical system converging a light beam emitted by the laser light source onto an optical disk, a photo detector receiving reflected light reflected by the optical disk, and an aberration correcting optical system controlling aberration of the converging optical system; a motor rotating the optical disk; and a control section receiving a signal from the photo detector, wherein the converging optical system has an objective lens formed using resin as a main material, the aberration correcting optical system has a spherical aberration correcting element correcting spherical aberration, and the control section evaluates quality of a reproduction signal for information in the optical disk by using the reflected light received by the photo detector, and utilizes a result of the evaluation to perform closed loop control on the spherical aberration correcting element.
    Type: Grant
    Filed: January 27, 2012
    Date of Patent: June 4, 2013
    Assignee: Panasonic Corporation
    Inventors: Yoshiaki Komma, Fumitomo Yamasaki, Toshiyasu Tanaka, Kanji Wakabayashi
  • Patent number: 8451698
    Abstract: An optical disk reproducing device includes: a signal reproducing section configured to read and decode information recorded on an optical disk by an optical pickup unit, and reproduce the information, wherein the signal reproducing section includes a gain controlled amplifier circuit configured to amplify an radio frequency signal generated from a light receiving element, an automatic gain control circuit configured to control a gain of the gain controlled amplifier circuit, and a signal processing section configured to derive a part of an automatic gain control value generated in the automatic gain control circuit, and generate a control signal for adjusting one of an optical system path and a detection system path for controlling the optical pickup unit.
    Type: Grant
    Filed: June 1, 2010
    Date of Patent: May 28, 2013
    Assignee: Sony Corporation
    Inventors: Nobuyuki Asai, Nobuyoshi Kobayashi, Yuji Gendai, Kazumasa Nishimoto, Masaaki Ishihara, Satoshi Kato
  • Patent number: 8451697
    Abstract: A disk drive is disclosed comprising a head actuated over a disk comprising a plurality of spiral tracks. During a seek operation, a demodulation window is opened in response to a window offset during a first revolution of the disk, wherein the demodulation window corresponds to the head approaching a spiral track. A window position error signal (PES) is generated representing a difference between a target framing of the demodulation window around the spiral track crossing and a detected framing of the demodulation window around the spiral track crossing. The window offset is adjusted in response to the first window PES, and the demodulation window is opened in response to the adjusted window offset during a second revolution of the disk.
    Type: Grant
    Filed: May 23, 2011
    Date of Patent: May 28, 2013
    Assignee: Western Digital Technologies, Inc.
    Inventors: Brian P. Rigney, Siri S. Weerasooriya, Steven C. Smith
  • Patent number: 8441899
    Abstract: An apparatus and a method for compensating periodic signal in an optical disc drive are described. The control apparatus includes an amplitude processing unit, a phase processing unit, a wave generator, a first switch module and a second switch module. The amplitude processing unit processes the amplitude of the input signal based on a reference signal for generating an amplitude signal. The phase processing unit processes the phase of the input signal based on the reference signal for generating a phase signal. The first switch module switches the amplitude signal to select one of the amplitude value and a predetermined amplitude value. The second switch module switches the phase signal to select one of the phase value and a predetermined phase value. The wave generator generates a compensated wave signal based on the selected amplitude value and the selected phase value, and outputs the compensated wave signal.
    Type: Grant
    Filed: July 12, 2011
    Date of Patent: May 14, 2013
    Assignee: Mediatek, Inc.
    Inventor: Kuo-jung Lan
  • Patent number: 8437231
    Abstract: A servo control device includes a plurality of reproduction channels, a plurality of analog/digital (A/D) converters, a servo error detecting circuit that generates a servo error signal, a servo signal processing device that executes predetermined processing for the servo error signal to generate a control signal, and a sampling frequency converter that converts the sampling frequency between the servo error detecting circuit and the servo signal processing device. A first clock is included as a sampling clock of the A/D converters and a processing clock of the servo error detecting circuit. A second clock is included as a processing clock of the servo signal processing device. The sampling frequency converter converts the sampling frequency by processing the servo error signal by the servo error detecting circuit in synchronization with the first clock and processing the signal processed in synchronization with the first clock in synchronization with the second clock.
    Type: Grant
    Filed: June 26, 2012
    Date of Patent: May 7, 2013
    Assignee: Sony Corporation
    Inventor: Nobuyoshi Kobayashi
  • Patent number: 8427913
    Abstract: A servo control signal generation device for discriminating a kind of an optical disk, changing over between top and bottom envelope signals of an RF signal, and generating a defect signal and a mirror signal includes an RF generator for generating the RF signal from reflected light of an optical disk, a disk discriminator for discriminating a kind of the optical disk from the RF signal, and a top envelope generator and a bottom envelope generator respectively for generating the top and bottom envelope signals of the RF signal. If the disk has reflectance after recording which is lower than that before recording, the defect and mirror signals are generated respectively from the top and bottom envelope signals. If the disk has reflectance after recording which is higher than that before recording, the defect and mirror signals are generated respectively from the bottom and top envelope signals.
    Type: Grant
    Filed: January 19, 2010
    Date of Patent: April 23, 2013
    Assignees: Hitachi, Ltd., Hitachi-LG Data Storage, Inc.
    Inventor: Yoshinori Ishikawa
  • Patent number: 8422341
    Abstract: An apparatus 100 according to the present invention is designed to read and/or write data from/on an information recording medium 1 using near-field light. The apparatus 100 includes: a light source 3 for emitting laser light; a condensing section 7 for producing the near-field light based on the laser light; a detecting section 22, 23 for detecting the relative positions of the condensing section 7 and the information recording medium 1; and a control section 14 for controlling the position of the condensing section 7. In starting a gap servo operation, the control section 14 controls the position of the condensing section 7 so that the gap servo operation is started at a different location on the information recording medium 1 from any other location where the gap servo operation has ever been started.
    Type: Grant
    Filed: April 22, 2008
    Date of Patent: April 16, 2013
    Assignee: Panasonic Corporation
    Inventors: Kenji Narumi, Masahiro Birukawa
  • Patent number: 8411543
    Abstract: A recording apparatus including: a light-illuminating/receiving-unit illuminating an optical-disc-recording-medium through a common object-lens with recording-light and ATS-light and receiving reflected-ATS-light; a rotation-driving-unit driving rotation of the medium; a tracking-mechanism driving the lens in a tracking-direction parallel to the radial direction; a tracking-error-signal-generation-unit generating a tracking-error-signal; and a tracking-servo-controller performing tracking-servo-control on the lens based on the tracking-error-signal, wherein the tracking-servo-controller includes: a servo-calculation-unit based on the tracking-error-signal in a feedback-loop as a tracking-servo-loop; and a feed-forward-controller calculating an estimated control-target-value of the tracking-servo-control based on an estimated illumination-spot-position value of the ATS-light obtained in a first-filter-process emulating a transfer-characteristic of the tracking-mechanism on an output of the servo-calculation-un
    Type: Grant
    Filed: October 4, 2011
    Date of Patent: April 2, 2013
    Assignee: Sony Corporation
    Inventor: Yoshiyuki Urakawa
  • Patent number: 8406105
    Abstract: A model is derived for write parameters of a laser in an optical drive. A parameter range for the write parameters is set based on a recordable medium. A number of test runs are recorded on the recordable medium while varying the write parameters. Write performance characteristics are measured over the test runs, and a model of write performance as a function of the write parameters is derived. Values for write parameters are selected for use in writing actual data based on the derived model. A first section of user data is written to the data-carrying region of the recordable medium using the selected values. The write performance characteristics of the first section of user data are measured, and the model is updated by including the measurements from the data-carrying region. New values for the write parameters of the laser are selected based on the updated model.
    Type: Grant
    Filed: July 8, 2011
    Date of Patent: March 26, 2013
    Assignee: Marvell International Ltd.
    Inventors: Peter Kivits, Jents Temmerman
  • Patent number: 8395976
    Abstract: An optical disc apparatus can make the focus of an information light beam converged by an objective lens agree with a target track of a target mark layer of an optical disc by appropriately predefining the distance between the focus of a servo light beam and that of the information light beam with regard to the direction of the thickness and a radial direction of the optical disc by means of the optical pickup of the apparatus and then operating for focus control and tracking control of the objective lens so as to make focus of the servo light beam converged by the objective lens agree with a reference track of a reference mark layer.
    Type: Grant
    Filed: November 17, 2008
    Date of Patent: March 12, 2013
    Assignee: Sony Corporation
    Inventors: Kimihiro Saito, Hirotaka Miyamoto, Toshihiro Horigome
  • Patent number: 8391111
    Abstract: An optical pickup control circuit includes an adding portion that adds a tracking driving signal which is for moving an objective lens, provided to face a discoid optical information recording medium, in a tracking direction of the corresponding optical information recording medium, to a tilt driving signal which is for moving the corresponding objective lens in a tilt direction of the corresponding optical information recording medium, and supplies the signal to a tilt actuator.
    Type: Grant
    Filed: June 7, 2011
    Date of Patent: March 5, 2013
    Assignee: Sony Corporation
    Inventors: Takao Maruyama, Muneyuki Horiguchi, Hitoshi Sakaguchi
  • Patent number: 8363532
    Abstract: A method and apparatus to control a position in which data is to be recorded on a holographic data recording medium by using interference between a reference light and a signal light, the method including: irradiating the reference light and the signal light on the holographic data recording medium; generating a focus error signal that indicates a distance difference between a first focus corresponding to a focus of the reference light on the holographic data recording medium and a second focus corresponding to a focus of the signal light on the holographic data recording medium, based on information about a reflective signal light generated when the irradiated signal light is reflected from a reflective transmission layer of the holographic data recording medium; and moving the second focus to a position of the first focus, based on the focus error signal.
    Type: Grant
    Filed: October 1, 2009
    Date of Patent: January 29, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Young-jae Park, Jae-cheol Bae, In-Joo Kim
  • Patent number: 8355302
    Abstract: Aspects of the disclosure can provide a method for generating an offset correction signal with a reduced circuit footprint. The method can include converting samples of a wobble signal into digital values having a reduced number of bits, integrating the digital values having the reduced number of bits over a specified time interval to determine an error signal, and generating an offset correction signal based on the determined error signal.
    Type: Grant
    Filed: June 15, 2009
    Date of Patent: January 15, 2013
    Assignee: Marvell International Ltd.
    Inventor: Mats Oberg