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Class 369/44.32 - Means to compensate for defect or abnormal condition


Subclass of Class 369 - Dynamic information storage or retrieval
Definition: Subject matter wherein the servo system structure or operation
No. of patents: 1199
Last issue date: 05/22/2012


1                      
NumberTitleIssue Date
8184510Method of recording and reproducing an optical recording medium
There is provided a method of recording and reproducing an optical recording medium which performs a tracking servo and a focusing servo by irradiating a laser beam onto determined positions including lands and grooves of a track of the recording medium and detectin...
05/22/2012
8180196Optical recording/reproducing apparatus and data recording method thereof
An optical recording/reproducing apparatus and a data recording method thereof. The optical recording and/or reproducing apparatus includes: an encoder which encodes a data for recording in a specified format; an optical pickup which records the encoded data onto a ...
05/15/2012
8179753Positioning control unit and optical disk drive
A position-error-signal calculation circuit (105) calculates a relative position error between a laser-focused-beam spot (103) and an information recording layer (102), and generates a focus error signal (106). A filter (108) ampli...
05/15/2012
8174941Optical disc apparatus, crosstalk correction method and integrated circuit
When a focus error signal (FE signal) is detected with an astigmatic method, a track crossing component leaks into the FE signal. Another detection method for the FE signal would reduce the leaking signal, but is not applicable when the light use efficiency decrease...
05/08/2012
8164991Optical disk apparatus and optical pickup device
A temperature sensor is disposed in an optical pickup to detect a temperature of an objective lens. An optical element (for example, a collimator lens) is driven according to a temperature change of the objective lens, which corrects deterioration of an optical char...
04/24/2012
8144553Disk drive
A disk drive for driving a disk is disclosed, which includes: a driving unit configured to provide a driving force onto the disk, a main circuit pattern electrically connected with the driving unit, a sensor unit configured to sense a rotation speed of the disk, a f...
03/27/2012
8130604Spherical aberration compensation method and device of optical disc drive
A spherical aberration compensation method is provided. A first thickness of a cover layer at a first radius position of an optical disc is measured. A second thickness of the cover layer at a second radius position of the optical disc is measured. A spherical aberr...
03/06/2012
8130603Optical disk driving apparatus, optical disk driving system, vehicle equipped with optical disk driving system, method of correcting spherical aberration in optical disk driving apparatus, program and recording medium
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 opt...
03/06/2012
8121001Method and device for protecting a servo in reading signals on a defect disc
A device for protecting a servo in reading signals on a defect disc from disturbance and instability is provided. The device includes a defect detection unit and a logic combination unit. The defect detection unit receives a plurality of defect detection signals to ...
02/21/2012
8107330Information recording and reproducing apparatus
An information recording and reproducing apparatus for increasing a speed of tilt control, including a portion for storing reference data, a portion for storing sample values data, a portion for obtaining positional information, a stilt servo generator, a tilt adjus...
01/31/2012
8089835Optical disc apparatus and tracking control method
An optical disc apparatus of the present application has a lens position signal generator for generating a lens position signal representative of a position of an objective lens in a disc radial direction, an amplitude corrector for correcting an amplitude of a trac...
01/03/2012
8081544Method and apparatus for deciding spherical aberration compensation value
A method and an apparatus for deciding a spherical aberration compensation (SAC) value for an optical storage medium are provided. The optical storage medium comprises at least one recording layer and a cover layer. The SAC value is suitable for a selected one of th...
12/20/2011
8077565Optical disc device and lens tilt control method
With an optical disc apparatus of the present invention, the number of tracks of an optical disc crossed by a light spot when the tracking control is inactive is measured and stored in a memory for each passage of a predetermined rotation angle. When the tracking co...
12/13/2011
8054716Optical disc apparatus and defocus control method
A defocus adjustment method includes a step of storing in a memory a range of defocus values for smooth operation of an optical disc apparatus, a step of measuring the defocus value of the optical disc loaded in the optical disc apparatus, a step of comparing the de...
11/08/2011
8050154Drive control apparatus, drive control method and optical pickup apparatus
A control unit is caused to drive a collimator lens from a position of an origin, by a clock number A of drive pulses of a pulse rate T1, thereby to move the collimator lens, and is caused to return the lens to the position of the origin at a pulse rate T2...
11/01/2011
8040766Method and apparatus for compensating for defect of storage medium
An apparatus for compensating for a defect of a storage medium of an optical driving includes a memory to store sample values of a servo driving signal during at least one track sampled by a first signal and cycle information about the first signal; a servo driving ...
10/18/2011
8031566Gap servo control method and apparatus in near-field optical disc drive
A gap servo control method and apparatus for increasing a disturbance cancellation capability and decreasing the occurrence of an overshoot in a near-field optical disc drive include: generating an actuator driving signal of a transient response process by using a s...
10/04/2011
8031565Optical pickup and optical information reproduction system
In an optical disk apparatus having an exclusive RF detector plane mounted therefore, as a method of obtaining a synthesized readout signal based on band-synthesis is used in order to obtain a readout signal having a good S/N ratio, a waveform distortion easily caus...
10/04/2011
8027231Information recording apparatus and method, information reproducing apparatus and method, and computer program
An information recording apparatus (1) is provided with: a first judging device (191) for judging whether or not a tracking error signal is greater than or equal to a first threshold value; a detecting device (192) for detecting, as a detection ...
09/27/2011
8027232Devices and methods for determining a critical rotation speed of an optical data carrier, monitoring a condition of an optical data carrier, and generating a reference signal
A device determines a critical rotation speed of an optical data carrier at which a critical deflection of said optical data carrier may occur. The device includes a drive unit, a measurement unit and a determination unit. The drive unit rotates the optical data car...
09/27/2011
8009526Optical pickup device and collimate lens
It is an object of the present invention to provide an optical pickup device being capable of correcting coma aberration induced in a light-condensing optical system including an objective lens for an optical disc and having a reduced size and a reduced thickness in...
08/30/2011
8009525Optical disc signal processing device, optical disc signal processing method, optical disc reproduction and recording device, and optical disc reproduction and recording method
An optimum method for adjusting the physical position or angle of an optical pickup (a1) is automatically selected for each optical disc signal processing device so that a control target value after adjusted is included in a previous margin measurement result...
08/30/2011
8000186Acting track-crossing during tracking error adjust
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 ...
08/16/2011
8000187Optical disc device
An optical disc device includes: a first searching part which searches a condition where amplitude level of a TE signal is made maximum by changing either one of position of a movable lens and a focus balance value in a state where a focus servo control is performed...
08/16/2011
7995429Optical disk device and tilt correction method thereof
There are provided an optical disk device and tilt correction processing method for performing recording/reproduction by rapidly acquiring an optimal tilt correction value for an optical disk having a plurality of recording/reproducing layers. In an optical disk dev...
08/09/2011
7983121Optical axis shift correcting device and method, and computer program
An optical axis shift correcting device is provided in an optical information device including an irradiation element for applying a laser, an optical system for guiding a laser applied to an optical disc having a recording track, and a light reception element for r...
07/19/2011
7983122Defocus detection device, defocus detection method and optical disk unit using the same
Defocus detection device and method capable of detecting a defocus accurately during recording of information to an optical disk having a plurality of recording layers and an optical disk unit using the device and method are provided. A temporal restriction is impos...
07/19/2011
7961567Optical disk apparatus
In an optical disk apparatus according to an exemplary embodiment of the invention, a management information retaining unit retains an information group which should regularly be recorded as disk management information. The disk management information is obtained fr...
06/14/2011
7957233Near-field gap pull-in method and optical disc apparatus therefor
A gap pull-in method and an optical disc apparatus. Whether light condensed on a disc as an actuator ascends is near-field light is determined using a gap error signal. The range of an actuator driving voltage value during a section where the decrease rate of the ga...
06/07/2011
7957234Optical pickup apparatus
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 ...
06/07/2011
7952965Optical pickup device, optical pickup controller and optical pickup control method
An optical pickup device such that the driving force of the drive unit provided on the same optical base as that of the objective lens exerts no adverse influence on controlling of the objective lens is provided. The optical pickup device 1 has an objective l...
05/31/2011
7948841Diffraction grating, optical pickup device and optical disc apparatus
A pickup device splits and detects a light beam reflected from a disc with the use of a grating. The grating has first to six areas, wherein the first area and the second area, the third area and the fifth area, and the fourth area and the sixth area are arranged in...
05/24/2011
7940612Optical disc apparatus and control method thereof
The present invention provides an optical disc apparatus that reduces access time while suppressing the emanation of heat from a beam expander. A microcomputer manages the operation time and pause time of a stepping motor constructed to move the movable lens of the ...
05/10/2011
7940611Optical disc apparatus
An optical disc apparatus comprises an overcurrent detector and when the overcurrent detector detects an overcurrent during a recording operation or a reproduction operation and during an operation for controlling a focus of an objective lens, a rotation speed of an...
05/10/2011
7929387Adjusting system for adjusting tilt of an optical pickup head
An adjusting system for adjusting a tilt of an optical pickup head includes a collimator, a processing device, and a controller. The collimator receives reflected light beams from the optical pickup head and generating images from the reflected light beams. The proc...
04/19/2011
7929386Optical disc device
A focus error signal is generated by a first-order diffracted light diffracted by regions 23b, 24b on a hologram plane 2a, and an offset of a tracking error signal is canceled by first-order diffracted light diffracted by re...
04/19/2011
RE42235Compensation method and device for tracking operation of optical storage system
An optical storage system includes a pickup head for picking up data from a storage medium. Firstly, the maxima of a tracking error signal and runout are obtained in a calibration procedure in a close loop formed by an optical pickup head, a pre-amplifier, a compens...
03/22/2011
7911893Disc device
A disc device capable of achieving a slimming down of a tilt adjusting portion is provided. A tilt adjusting member 404 of a tilt adjusting portion 400 moves an optical pickup driving portion 307 along a guide face 401a to adjust a...
03/22/2011
7907482Method and system for correction of errors
A method and system for removing periodic disturbances pertaining to turntable and spindle motor errors during recording of a blank optical information carrier. The periodic disturbances are determined in advance and removed only during recording by a repetitive con...
03/15/2011
7898911Optical pickup apparatus equipped with a lens angle adjusting member and a semiconductor laser element
In an optical pickup apparatus, a collimator lens is rockably supported by edges of two protruding portions formed on opposing sides of a groove of an optical base. The collimator lens is urged against the edges of the two protruding portions by a leaf spring. The p...
03/01/2011
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