| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 369440130 | Dithering or wobbling the beam or track | 49 |
| 20080205207 | Radial Tracking Method and Apparatus for an Optical Information Carrier Format with Non-Uniformly Spaced Tracks - A radial tracking method for an optical information carrier format with non-uniformly spaced tracks is disclosed, wherein a plurality of tracks ( | 08-28-2008 |
| 20080205208 | Optical System With Filtered Push Pull Radial Tracking - The present invention relates to optical system capable of reproducing information from an optical carrier by a main beam (C) for reading information as readable effects on the carrier, and a first (A) and a second (B) auxiliary beam. The optical system is adapted to direct the main beam (C) and the first (A) and second (B) auxiliary beam onto the carrier so that the main beam is positioned on a first track, and the first and second auxiliary beam are oppositely positioned on a second and a third track. The optical system can adjust a push pull (PP) radial error signal from the main beam by a function; ƒ=ƒ(A, B, C), where the function ƒ is dependent upon adjacently positioned readable effects in the first, second and third track i.e. the local optical environment of the main beam. Therefore a filtering or “cleaning” of the push pull signal is performed depending on the local optical environment of the main beam. | 08-28-2008 |
| 20080219108 | Device and Method for Scanning an Optical Recording Medium and Optical Recording Medium - The present invention relates to a device ( | 09-11-2008 |
| 20080232202 | APPARATUS AND METHOD OF REPRODUCING WOBBLE SIGNAL - An apparatus for reproducing a wobble signal, including: a first filter unit receiving a wobble signal obtained by reading a wobble from a disc and passing a first band including a monotone frequency set according to the type or speed of the disc so as to generate a first wobble output signal; a second filter unit, when the wobble signal includes at least one frequency component, receiving the wobble signal and passing a second band including a multi-frequency set according to the speed of the disc so as to generate a second wobble output signal; and a wobble clock signal generation unit generating a wobble clock signal by quantizing one of the first and second wobble output signals. Accordingly, the wobble signal can be detected according to the type of disc, the speed of a disc, or a driving mode for the disc. | 09-25-2008 |
| 20080239889 | DEMODULATION CIRCUIT AND OPTICAL DISK DRIVE - A demodulation circuit accurately demodulates a wobble signal of an optical disk without being affected by a phase shift induced by crosstalk. An A-D converter subjects wobble signal reproduced from an optical disk to A-D conversion and feeds a result of conversion to a zero-crossing detection circuit. The zero-crossing detection circuit detects zero-crossing points of the wobble signal. A sinusoidal wave generation circuit generates a sinusoidal wave by means of sequentially connecting sinusoidal wave elements whose periods are each equal to a time interval between zero-crossing points. A multiplier multiplies an original wobble signal by a sinusoidal wave signal. A slicer detects an HMW-modulated portion of the wobble signal, and another slicer detects an MSK-modulated portion of the wobble signal. | 10-02-2008 |
| 20080247280 | Optical Drive with Constant Radial Bandwidth - The invention relates to an optical drive for e.g. CD, DVD, HD-DVD or BD disks. A radial servomechanism controls the radial position of a laser beam in response to a push pull signal (PP). The radial servomechanism has an amplifier (VGA, | 10-09-2008 |
| 20080259749 | Recovery of Lost Track Focusing on an Optical Disc - A method for restoring focusing of a laser beam on a track of an optical disc for reading or writing data from/to the track when the focusing of said beam onto said track has been lost, wherein two categories, A and B, of focus lost causes are defined, A being due to an external shock and B due to other reasons and wherein a focus re-capture is performed with the use of focus control information stored in a memory only for a category B focus lost. | 10-23-2008 |
| 20080285394 | OPTICAL DISC APPARATUS AND METHOD OF PROCESSING SYNCHRONIZATION SIGNAL FOR THE APPARATUS - An optical disc apparatus includes a reproduction unit that reproduces a wobble signal on an optical disc, the wobble signal having physical address information subjected to phase modulation by using a code sequence that has a predetermined cycle and that is subjected to code modulation in accordance with a modulation rule common to the cycles; a phase detection unit that performs phase detection to the reproduced wobble signal to demodulate the code sequence; an evaluation value calculating unit that sequentially calculates an evaluation value indicating how much the code sequence coincides with the modulation rule in units of codes in the code sequence; an integrator that cyclically integrates the evaluation value in the cycle; and a synchronous detection unit that detects the presence of the code sequence and a reference position of the code sequence from the integrated evaluation value. | 11-20-2008 |
| 20080304374 | Initial Focus Optimization for an Optical Scanning Device - In a particular type of high-density optical recording systems, a solid immersion lens (SIL) is used in the objective system to focus a radiation beam onto an information layer of an optical record carrier. The distance between the exit surface of the SIL and the entrance surface of the record carrier is typically 25 nm to allow evanescent coupling of the radiation from the SIL to the optical record carrier for a system using a blue laser as radiation source. Such a system is also called a near-field system, deriving its name from the near field formed by the evanescent wave at the exit face of the SIL. A suitable gap signal, representing the width of the gap, is used to control the width of the gap during operation of the system. Tolerances in the optical elements and opto-mechanical components of the optical system of the optical recording system can lead to an offset in the position of the focus point of the objective system. The offset can be larger than the typically used gap width for such a recording system. This can lead to direct contact between the SIL and the record carrier, which may result in damaging one or both of them. The invention discloses a method and implementation for a focus initialization correcting the focus offset of the optical system used to read out or record the optical record carrier such that a reliable and robust gap signal can be derived for gap width control. | 12-11-2008 |
| 20080316876 | Optical disk - The invention provides an optical disk that enables high-speed reproduction of address signals. A wobble address system for optical disk supports various types of synchronization, such as phase synchronization, bit synchronization, word synchronization, etc., to be established easily with high detection reliability with the use of an self-orthogonal code. Thus, the invention provides a method for easily synchronizing an address signal, i.e., high-speed reproduction of the address signal. Further, by virtue of an efficient modulation system of the address signal and redundancy thereof, it becomes possible to detect address information with high reliability. This capability is particularly effective in optical recording/reproduction with a blue light source whose signal light quantity and reproduction quality are prone to reduce. Moreover, other additional data of the address data is preserved in the wobbles, which provides medium information to a rewritable optical disk without using embossed pits such that a high-reliability disk (with enhanced security) is realized with a low cost and easily. | 12-25-2008 |
| 20090003148 | INFORMATION RECORDING SYSTEM AND AN INFORMATION RECORDING METHOD - An information recording system for recording information on an optical disc using a reference clock signal generated based on a push-pull signal including a wobble frequency component, the system includes an amplitude obtaining unit for obtaining an amplitude value of the push-pull signal, a threshold calculation unit for calculating a displacement threshold of the push-pull signal based on the amplitude value obtained by the amplitude obtaining unit, and a noise reduction unit for generating a corrected push-pull signal by correcting the push-pull signal such that a displacement exceeding the displacement threshold is reduced. The reference clock signal is generated based on the corrected push-pull signal generated by the noise reduction unit. | 01-01-2009 |
| 20090022016 | RECORDING MEDIUM HAVING A SUBSTRATE CONTAINING MICROSCOPIC PATTERN OF PARALLEL GROOVE AND LAND SECTIONS AND RECORDING/REPRODUCING EQUIPMENT THEREFOR - An information recording medium | 01-22-2009 |
| 20090022017 | RECORDING MEDIUM HAVING A SUBSTRATE CONTAINING MICROSCOPIC PATTERN OF PARALLEL GROOVE AND LAND SECTIONS AND RECORDING/REPRODUCING EQUIPMENT THEREFOR - An information recording medium | 01-22-2009 |
| 20090040888 | METHOD AND APPARATUS FOR GENERATING THE WOBBLE CLOCK SIGNAL - A method for generating a wobble clock signal. When the wobble signal becomes deformed or a defect on the optical disc is found, the present invention provides a stable wobble clock signal, which is used to maintain a stable rotation speed when the optical disc is processed. In addition, the present invention also determines whether the wobble signal is deformed according to the result of comparing the width of the wobble signal at different status with the average of the half cycle width of the wobble signal. | 02-12-2009 |
| 20090040889 | Wobble signal demodulation method and wobble signal demodulator - Pseudo synchronization due to crosstalk is detected with a small circuit scale in decoding address information from an MSK-modulated wobble signal. An MSK mark detection unit detects MSK marks periodically placed as synchronization signals in a wobble signal. A first synchronization state determination unit determines synchronization establishment with a detection position of each MSK mark as a reference, or out-of-synchronization. A prediction timing generation unit periodically generates a timing at which each MSK mark is to be detected based on the synchronization position after the establishment of synchronization. A second synchronization state determination unit compares a detection timing with the prediction timing, after the MSK mark is detected at a predetermined position within a period a predetermined number of times in succession, and determines the synchronization position as a pseudo synchronization position due to crosstalk on condition that there is a shift between the detection timing and the prediction timing. | 02-12-2009 |
| 20090073822 | SIGNAL PROCESSING METHOD OF WOBBLE SIGNAL, RECORDING AND REPRODUCING METHOD OF OPTICAL DISC, OPTICAL DISC APPARATUS, PROGRAM, AND RECORDING MEDIUM - In a method of and an apparatus for creating a reproduced wobble signal by subtracting an estimated crosstalk signal, expressed by a sine waveform having a frequency approximately equal to the meandering frequency of grooves, from an original wobble signal and recording or reproducing an information pattern at a predetermined position of an optical disc, a carrier signal, which is caused to correspond to the meandering of the groove by being subjected to phase synchronization, is assumed based on the reproduced wobble signal, a crosstalk remaining component is estimated from the amplitude and phase of the region, which meanders in approximately the same phase as the estimated carrier signal in the reproduced wobble signal, and from the amplitude and phase of the region which meanders according to a signal different from the estimated carrier signal, and the estimated crosstalk is updated to cancel the remaining component. | 03-19-2009 |
| 20090073823 | OPTICAL ELEMENT, OPTICAL HEAD, OPTICAL INFORMATION RECORDING AND REPRODUCTION APPARATUS, COMPUTER, IMAGE RECORDING DEVICE, IMAGE REPRODUCTION DEVICE, SERVER AND CAR NAVIGATION SYSTEM - The present invention provides a first light source ( | 03-19-2009 |
| 20090086589 | Optical Disk Having Wobble Patterns Representing Control Information - An apparatus for reading subdivided information from an optical disk, which comprises a track groove and on which information is recorded along the track groove is disclosed. The apparatus includes an optical head, which irradiates the optical disk with light and generates an electric signal responsive to part of the light that has been reflected from the optical disk, read signal processing means for generating a wobble signal which has an amplitude changing with the wobble pattern from the electric signal, rise value acquiring means for sampling and holding an absolute gradient value of the wobble signal when the signal rises, fall value acquiring means for sampling and holding an absolute gradient value of the wobble signal when the signal falls, and subdivided information detecting means for determining the subdivided information by majority by comparing the values held by the rise and fall value acquiring means with each other. | 04-02-2009 |
| 20090103402 | METHOD AND APPARATUS FOR GENERATING ABSOLUTE TIME IN PREGROOVE DATA - An apparatus and a method for generating an ATIP data are provided. The apparatus, based on a wobble signal generated by reading a re-writable compact disc, generates an ATIP data; the apparatus includes: a frequency demodulator for demodulating the wobble signal to generate an original ATIP data signal; an ATIP clock generating circuit for generating an ATIP clock signal based on the wobble signal; and a data generating circuit, coupled to the frequency demodulator and the ATIP clock generating circuit, for generating the ATIP data based on the number of the original ATIP data signal at a first logic level during one period of the ATIP clock signal. This apparatus uses the number of the original ATIP data signal at a first logic level during one period of the ATIP clock signal and the bi-phase rule to precisely generate the ATIP data. | 04-23-2009 |
| 20090109806 | TE SIGNAL POLARITY DETERMINING SYSTEM AND RELATED METHOD THEREOF - A TE signal polarity determining method, includes: (a) obtaining a wobble related signal, an RF related signal, a TE signal and an accessing direction; and (b) determining if an original polarity of a TE signal should be changed or not according to phases of the RF related signal, the wobble related signal and/or the accessing direction. | 04-30-2009 |
| 20090109807 | TE SIGNAL POLARITY DETERMINING SYSTEM AND RELATED METHOD THEREOF - Disclosed is a TE signal polarity determining method, which includes: (a) obtaining a detection signal from an optical disc; (b) obtaining characteristics of the detection signal corresponding to different polarities of the TE signal; and (c) determining whether an original polarity of the TE signal should be changed or not according to the obtained characteristics. | 04-30-2009 |
| 20090116344 | INFORMATION RECORDING METHOD, INFORMATION RECORDING MEDIUM, AND INFORMATION RECORDING APPARATUS - An information recording method recording information on an information recording medium in the form of a recording mark having a time-length nT by irradiating optical beam pulses thereto according to a recording strategy, the recording strategy comprises the steps of forming the recording mark on the recording medium by controlling a power of the optical beam pulses to one of ternary values Pw, Pb and Pe (Pw>Pe>Pb) and irradiating a heating pulse having a power set to Pw, and a cooling pulse having a power set to Pb, upon the information recording medium alternately; and forming a space on the recording medium subsequent to the recording mark by irradiating the optical beam pulse with the power Pe, the recording strategy increasing the number of said heating pulses by one each time the time-length of the recording mark is increased by 2T, the recording strategy setting a heat pulse starting time sTtop and a heat pulse termination time eTtop for a first heating pulse, when forming a recording mark of a time-length of at least 2T, individually at least in the case of forming a space-length of 2T and the case in which there is formed a space-length of 3T or more, before or after the currently formed recording mark. | 05-07-2009 |
| 20090154305 | WOBBLE SIGNAL EXTRACTION CIRCUIT AND OPTICAL DISK DEVICE - A wobble signal extraction circuit includes: an RF signal component acquiring portion for acquiring an RF signal component from at least one of first and second signals received by two light receiving portions, the two light receiving portions being obtained through division in halves with a direction along which each track of an optical recording medium extends as a boundary; a wobble signal acquiring portion for acquiring a wobble signal by subtracting the second signal from the first signal; an RF signal component binarizing portion for binarizing the RF signal component; a wobble signal binarizing portion for binarizing the wobble signal; and an exclusive OR arithmetically operating portion for arithmetically operating an exclusive OR of the binarized RF signal component and the binarized wobble signal; wherein balances between amplitudes of the first and second signals are detected based on an arithmetic operation result obtained in the exclusive OR arithmetically operating portion. | 06-18-2009 |
| 20090161501 | FOCUS CONTROL METHOD AND OPTICAL DISC APPARATUS - According to one embodiment, when a focus servo goes off and the distance between an objective lens and a recording layer of an optical disc does not coincide with a focal length of the objective lens, a control voltage or current corresponding to an optical disc wobble stored in a memory is superimposed on a control voltage or current supplied to a driving mechanism to move an objective lens along an optical axis for re-focusing, and the superimposed voltage or current is supplied to the driving mechanism. Therefore, pull-in of a focus servo for re-focusing is possible in a short time. | 06-25-2009 |
| 20090201775 | Optical Disc Apparatus and Method for Discriminating Optical Disc - This invention improves the accuracy of wobble signal detection for disc discrimination and reduces discrimination errors due to noise. In an optical disc apparatus, a wobble signal generator creates a wobble signal from an electrical signal which has been obtained from conversion by a pickup. A bandpass filter (BPF) is set to change its central frequency to a wobble frequency f | 08-13-2009 |
| 20090245037 | Focus Servo Method, Optical Reproducing Method, and Optical Reproducing Apparatus - A focus servo method includes: causing light to enter an objective lens at an eccentric position; irradiating light onto recording marks of an optical recording medium in an oblique direction with respect to a thickness direction of the optical recording medium; detecting light reflected by the recording marks as a reflection of the light irradiated onto the recording marks; and controlling a position of the objective lens based on the detected light. | 10-01-2009 |
| 20090274018 | RECORDING DEVICE AND RADIAL OFFSET CALIBRATION METHOD - The present invention relates to a method of calibrating a radial offset of an optical recorder after a recordable record carrier is inserted ( | 11-05-2009 |
| 20090279396 | Misjudgment correction circuit and optical disk drive - Disclosed herein is a misjudgment correction circuit, including, an edge detection section configured to detect, in a binarized full addition signal obtained by adding first and second signals of the same or opposite polarity, edges at which the logic value of the binarized signal changes, a push-pull signal acquisition section configured to acquire a binarized push-pull signal obtained by subtracting the second signal from the first signal, a majority decision calculation section configured to acquire, in chronologic order, a plurality of logic values of the push-pull signal between the two adjacent edges so as to determine, by a majority decision, the more numerous of the two logic values, and a wave correction section configured to correct the push-pull signal between the edges to the more numerous logic value determined by the majority decision calculation section. | 11-12-2009 |
| 20090285058 | MASTERING DEVICE, DISC MANUFACTURING METHOD, DISC-SHAPED RECORDING MEDIUM, DISC REPRODUCTION DEVICE, AND DISC REPRODUCTION METHOD - Second digital information serving as copyright protection information can be stably and reliably read without any effect of a defect or pit missing on a disk-shaped recording medium. | 11-19-2009 |
| 20100034059 | DISK RECORDING MEDIUM, DISK DRIVE APPARATUS, REPRODUCTION METHOD, AND DISK MANUFACTURING METHOD - A recording and reproducing area and a reproduction-only area are formed by wobbling a groove formed in a spiral fashion to form a track to be tracked on a disk. The recording and reproducing area has address information recorded by wobbling of the groove and information recorded and reproduced by phase change marks on the track formed by the groove where the address information is recorded. The reproduction-only area has prerecorded information recorded by wobbling of the groove. | 02-11-2010 |
| 20100195454 | Optical disc recording apparatus - An optical pickup is disposed which irradiates a laser beam onto an optical disc where a guide groove having characteristics of thermal interference (heat discoloration) is spirally formed. The optical pickup irradiates the laser beam along the guide groove to conduct one of data recording in which pits indicating a data length are formed, and visible-image formation in which a part of the optical disc is discolored. The laser beam irradiation position is controlled so that the data recording is conducted with starting from the inner peripheral side of the optical disc, and the visible-image formation is conducted with starting from the outer peripheral side of the optical disc. | 08-05-2010 |
| 20100315911 | Optical Disk Apparatus - An optical disk apparatus to record data on an optical disk on which a wobble is formed, the optical disk apparatus including; a detection unit including a BPF which a signal obtained from a reflected light from an optical disk passes, the detection unit to detect a wobble signal from a wobble based on the signal passing the BPF; and a register to store an adjustment value for adjusting the BPF as a register value, so as to adjust the BPF based on each of register values obtained by changing the register value 1 LSB by 1 LSB; acquire an amplitude of the signal passing the BPF, the amplitude corresponding to each of the register values; identify one of the register values for the largest acquired amplitude; and adjust the BPF based on a value obtained by adding 1 LSB to the identified register value when data is recorded. | 12-16-2010 |
| 20100329088 | DEVICE FOR DETERMINING EXISTENCE OF WOBBLE, MEDIUM DISCRIMINATION DEVICE, METHOD OF DETERMINING EXISTENCE OF WOBBLE, AND MEDIUM DISCRIMINATION METHOD - The invention device has amplitude correction means for generating, from a radial push-pull signal, a wobble signal which has been corrected such that the amplitude of a predetermined frequency component is kept substantially constant, and for outputting a magnification for correcting the amplitude of the predetermined frequency component as a gain control signal, and determination means for determining whether or not wobble exists based on a minimum value of the magnification indicated by the gain control signal. | 12-30-2010 |
| 20110122742 | RECORDING MEDIUM HAVING A SUBSTRATE CONTAINING MICROSCOPIC PATTERN OF PARALLEL GROOVE AND LAND SECTIONS AND RECORDING/REPRODUCING EQUIPMENT THEREFOR - An information recording medium | 05-26-2011 |
| 20110122743 | RECORDING MEDIUM HAVING A SUBSTRATE CONTAINING MICROSCOPIC PATTERN OF PARALLEL GROOVE AND LAND SECTIONS AND RECORDING/REPRODUCING EQUIPMENT THEREFOR - An information recording medium | 05-26-2011 |
| 20110134730 | RECORDING APPARATUS AND CONTROL METHOD - A recording apparatus for performing information recording using formation of marks by focusing a first light with an objective lens at a given position in a recording layer included in an optical disc recording medium, includes: a rotation driving unit for rotating the optical disc recording medium; a focus servo control unit for condensing a second light which is different from the first light on a reflection film, and for controlling a position of the objective lens so that a focal position of the second light follows the reflection film; a recording position setting unit for setting an information recording position of the first light in a focus direction by changing the collimation of the first light; a surface wobbling amount estimating unit; and a surface wobbling estimation amount acquisition control unit for acquiring a surface wobbling estimation amount for each rotation angle within one revolution of the disc. | 06-09-2011 |
| 20110141863 | DATA STORAGE SYSTEM AND METHOD FOR CALIBRATING SAME - Disclosed herein are aspects of optical tape technology, tape manufacturing, and tape usage. Methods and systems of tape technology disclose optical tape media including: configurations, formulations, markings, and structure; optical tape manufacturing methods, systems, and apparatus methods and systems including: curing processes, coating methods, embossing, drums, testing, tracking alignment stamper strip; optical tape methods and systems including: pick up head adapted for the disclosed optical tape; and optical tape uses including optical storage media devices for multimedia applications | 06-16-2011 |
| 20110182158 | TE SIGNAL POLARITY DETERMINING SYSTEM AND RELATED METHOD THEREOF - A tracking error (TE) signal polarity determining method, comprising: (a) obtaining a wobble related signal and a TE signal from an optical pick-up unit accessing an optical disc; (b) determining an accessing direction; and (c) determining if an original polarity of the TE signal from the optical disc should be changed or not according to the relation between the wobble related signal and the accessing direction. | 07-28-2011 |
| 20110261661 | SEMICONDUCTOR INTEGRATED CIRCUIT AND OPTICAL DISK DEVICE HAVING THE SAME - 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. The first, second, third, and fourth light reception output signals are selectively supplied to the two A/D converters, the arithmetic circuit in a first operation mode generates a first addition output signal of A and C and a second addition output signal of B and D, the DPD generating circuit generates a digital phase comparison signal, the arithmetic circuit in a second operation mode generates a third addition output signal of A and D and a fourth addition output signal of B and C, and the wobble signal generating circuit generates a digital wobble signal. | 10-27-2011 |
| 20120075970 | OPTICAL DISC MEDIUM, REPRODUCTION METHOD THEREOF AND REPRODUCTION APPARATUS - The pit arrays on an optical disc medium are made to wobble at a frequency which is higher than the band of frequencies that a tracking servo can follow and which is lower than the band of frequencies of the reproducing signal. A wobble detection signal according to the amount of wobble is obtained from the tracking error signal and used as a reference signal for frequency acquisition. Alternatively, the pit arrays on the medium are wobbled at a frequency which is within the band of frequencies that the tracking servo can follow and which is lower than the band of frequencies of the reproducing signal. In addition, a wobble detection signal corresponding to the amount of wobble is obtained either from the output signal from a compensator included in a tracking servo system or from a tracking drive signal and is used as a reference signal for frequency acquisition. | 03-29-2012 |
| 20120087219 | WOBBLE SIGNAL EXTRACTING CIRCUIT, METHOD FOR EXTRACTING WOBBLE SIGNAL, AND OPTICAL DISK UNIT - A wobble signal extracting circuit includes: a readout signal generating circuit generating an RF signal by adding first and second detection signals corresponding to reflected light from inside and outside a recording track; a first subtractor generating a push-pull signal by subtracting the first and second detection signals, respectively; a first analog-to-digital converter (ADC) converting the RF signal to digital; a second ADC converting the push-pull signal to digital; a residual RF component generating circuit generating a residual RF signal component equivalent to the RF signal component remaining in the digitized push-pull signal; and a second subtractor generating the wobble signal by subtracting the residual RF signal component from the digitized push-pull signal. The residual RF component generating circuit generates the residual RF signal component so that it may approach the remaining RF signal component based on correlation between the wobble signal and the digitized RF signal. | 04-12-2012 |
| 20120201109 | Optical Pickup Apparatus - An optical-pickup apparatus includes: a diffraction grating that a laser beam enters, the diffraction grating being configured to generate a main beam that is 0th-order light and sub-beams that are +1st-order diffracted light and −1st-order diffracted light; an objective lens to focus the main and sub-beams onto a signal-recording layer; a main-beam light-receiving portion that the main beam reflected by the signal-recording layer is applied to; and sub-beam light-receiving portions that the sub-beams reflected by the signal-recording layer are respectively applied to, each light-receiving area of the sub-beam light-receiving portions being smaller than a light-receiving area of the main-beam light-receiving portion, wherein a focusing-control operation is performed by a differential astigmatic method using the main beam applied to the main-beam light-receiving portion and the sub-beams respectively applied to the sub-beam light-receiving portions. | 08-09-2012 |
| 20120307609 | RECORDING MEDIUM, REPRODUCTION AND RECORDING METHOD, REPRODUCTION AND RECORDING DEVICE - Obtain an expanded address without altering the bit number of an address which is embedded in a wobble. Generate a virtual bit which is not recorded on a disc, and which is expressed by the disparity from the rules and the presence or absence of information embedded in part or all of the wobble address. | 12-06-2012 |
| 20130033973 | OPTICAL RECORDING MEDIUM, RECORDING/REPRODUCING APPARATUS, RECORDING/REPRODUCING METHOD - 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. | 02-07-2013 |
| 20130064058 | OPTICAL DISC APPARATUS - 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. | 03-14-2013 |
| 20130176840 | Optical Pickup - An optical pickup includes a light source, an objective lens, a diffraction grating that divides an optical beam reflected from a predetermined information layer, into a plurality of optical beams, and a detector having a plurality of photo-receivers to receive a plurality of optical beams. The diffraction grating has a predetermined region for dividing from a signal light beam a region including a central portion of a spot which the signal light beam will form on the diffraction grating. A distance from a central section of the detector to that of a spot center photo-receiver on the detector, the spot center photo-receiver being provided to receive the optical beams formed by division in a predetermined region of the diffraction grating, is equal to or greater than a spot radius of the unwanted light beams entering the predetermined region of the diffraction grating, on the detector. | 07-11-2013 |
| 20140086029 | PRE-COMPENSATED OPTICAL TAPE WOBBLE PATTERNS - Amplitude or phase modulated un-compensated wobble patterns representing address patterns for track addresses of optical media are generated. A filter is applied to the un-compensated wobble patterns to pre-compensate the un-compensated wobble patterns. When an inverse of the filter is applied to a signal representing the pre-compensated wobble patterns in the presence of noise, the noise is suppressed and the un-compensated wobble patterns are substantially recovered. | 03-27-2014 |
| 20140112116 | RECORD CARRIER AND APPARATUS FOR SCANNING THE RECORD CARRIER - A record carrier has a servo track indicating an information track intended for recording information blocks. The servo track has a variation of a physical parameter, referred to as wobble. The wobble is modulated for encoding record carrier information, such as addresses. The servo track is subdivided in modulated parts in which the frequency and/or phase of the variation deviates from the wobble frequency, and non-modulated parts. The slope of the wobble is substantially continuous at transitions between the modulated and non-modulated parts by using wobbles starting at the maxima or minima of the wobble in a first part of the modulated parts. | 04-24-2014 |
| 20150146509 | QUADRATURE TRACK ERROR SIGNAL FOR OPTICAL RECORDING MEDIA AND DEVICES - A method for providing tracking error signals in an optical data storage system includes a step of receiving a wobble signal having a first frequency from the wobble detection system. The wobble detection system includes an optical pick up unit that detects positions of the head relative to lands and grooves. Characteristically, the wobble signal is amplitude modulated for positions intermediate between the land and the groove. The method further includes a step of receiving a primary tracking error signal from the wobble detection system. The wobble signal is multiplied with a synchronous signal to about a product signal. The product signal is positive for a first direction of motion and negative for a second direction of motion that is opposite that of the first direction. The product signal is integrated to obtain a quadrature track error signal. | 05-28-2015 |
