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Of storage or retrieval information signal

Subclass of:

369 - Dynamic information storage or retrieval

369530100 - CONDITION INDICATING, MONITORING, OR TESTING

369530110 - Including radiation storage or retrieval

Patent class list (only not empty are listed)

Deeper subclasses:

Class / Patent application numberDescriptionNumber of patent applications / Date published
369530350 Signal error correcting or detecting 37
369530340 Time based parameter 10
369530330 Unwanted signal component indicating 1
20090040897Reproducing signal measuring method, signal reproducing apparatus, and optical recording medium - Regarding a signal recorded with a first frequency in a recording area on a specific first recording layer and a signal recorded with a second frequency different from the first frequency in a recording area on a second recording layer which might cause interlayer crosstalk in relation to the first recording layer, a reproducing signal measurement method for a multilayer optical recording medium having at least three recording layers includes reproducing the signal recorded in the recording area on the first recording layer, separating signals recorded respectively with the first and second frequencies, discriminating signal amplitude of the first frequency and a maximum value in signal amplitude of the second frequency, and calculating a signal amplitude ratio between them to measure interlayer crosstalk contained in the signal reproduced from the recording area on the first recording layer. Thus, the interlayer crosstalk quantity caused by unnecessary light can be measured quantitatively.02-12-2009
369530320 Dropout indicating 1
20080285412Dropout Detection Device, Disk Reproduction apparatus, And Dropout Detection Method - A dropout detection device, a disk reproduction apparatus, and a dropout detection method for detecting the occurrence of a dropout are provided. A low-pass filter outputs, as a signal LFENV, a low-frequency component of an envelope signal ENV generated by an envelope generation circuit, which represents an upper envelope of a first RF signal RF11-20-2008
Entries
DocumentTitleDate
20100020661INFORMATION RECORDING APPARATUS AND METHOD, COMPUTER PROGRAM, AND RECORDING MEDIUM - An information recording apparatus (01-28-2010
20100157765COLLECTION OF READBACK SIGNAL MODULATION DATA - A data storage system having a read channel configured to function in a normal operation mode and a test mode. In the normal operation mode, the read channel is configured to decode a readback signal to obtain data bits. In the test mode, the read channel is configured to extract gain control loop data and/or timing control loop data from the readback signal.06-24-2010
20110032809INFORMATION RECORDING MEDIUM EVALUATION METHOD, INFORMATION RECORDING MEDIUM, METHOD FOR MANUFACTURING INFORMATION RECORDING MEDIUM, SIGNAL PROCESSING METHOD AND ACCESS CONTROL APPARATUS - A method for rating an information recording medium according to the present invention includes the steps of: receiving a digital read signal, which has been generated based on an analog read signal representing information that has been read from the information recording medium, and shaping the waveform of the digital read signal; subjecting the shaped digital read signal to maximum likelihood decoding, thereby generating a binarized signal showing a result of the maximum likelihood decoding; and calculating the quality of the digital read signal based on the shaped digital read signal and the binarized signal. If the quality of the read signal is calculated by a PRML method in which a number of zero-cross portions are included in a merging path of a minimum difference metric, the quality is calculated by using only a state transition pattern in which only one zero-cross portion is included in a merging path of a non-minimum difference metric.02-10-2011
20100278027APPARATUS AND METHOD FOR MEASURING SIGNAL QUALITY - An apparatus and method for measuring the quality of a signal on an optical disc based on level information of a viterbi decoder are provided. The signal quality measuring apparatus includes: a binary unit that generates binary signals from input RF signals; a channel identifier that receives the input RF signals and the binary signals output from the binary unit and outputs reference level values corresponding to the binary signals; and an information calculator that receives the reference level values and detects a signal quality value.11-04-2010
20090141604Optical disk, method for producing the same, and recording and reproducing apparatus - An optical disk includes a first area on which user information is recorded, and a second area in which a plurality of marks radially extending are arranged in a track direction in the optical disk. Information about the reflectance of the optical disk is recorded in the second area. It is intended to optimize the amplification factor of the reproduced signal on the basis of the information about the reflectance of the optical disk in the second area. Control data and user data can be reproduced quickly and highly reliably without depending on the relationship between the reflectances of a recording area and a non-recorded area of the optical disk.06-04-2009
20100128587METHOD AND RECORDER FOR REDUCING REJECTION OF RECORD CARRIERS DUE TO WRITE ERRORS - When writing on a recordable medium the recorder can encounter write errors. When a write error occurrs the record carrier is discarded. By ignoring write errors in sections of the record carrier comprising unused information, for instance sections of the lead-in or lead-out the record carrier no longer needs to be discarded.05-27-2010
20090303853Optical information recording/reproduction apparatus and recording condition adjusting method - An adaptive equalization circuit (12-10-2009
20090290466OPTICAL DISC APPARATUS, METHOD OF CONTROLLING THE SAME, AND INFORMATION STORAGE MEDIUM - An optical disc apparatus includes an optical pickup for outputting an output signal according to reflected light from an optical disc medium, measures a level of a reflected signal corresponding to reflected light from a medium surface prior to reading of information recorded on the medium, predicts, based on the measured level of the reflected signal, whether or not the reflected signal from the medium surface will satisfy a predetermined detection condition when a focus state is to be detected, and uses a result of the predicting to detect a state where the output signal satisfies the predetermined detection condition as a state where a focus of an objective lens included in the optical pickup is on a signal surface of the medium while relatively moving the objective lens with respect to the medium surface when the information recorded on the medium is to be read therefrom.11-26-2009
20100220570SIGNAL QUALITY EVALUATING APPARATUS AND METHOD, AND INFORMATION RECORDING MEDIUM - A signal quality evaluating method necessary for a signal quality evaluation index and a margin design is provided for an apparatus utilizing hologram recording techniques. An evaluation index is used being obtained by dividing root sum square of standard deviations of luminance value distribution of on- and off-pixels obtained from reproduced signals, by a difference between average values.09-02-2010
20080304388Optical Disc Recording Apparatus and Optical Disc Recording Method - In a recording/reproducing apparatus and a recording method, for enabling a high reliability on reproduction data are conducted the followings: recording a test mark within the test aria with a predetermined write strategy; obtaining signal amplitudes corresponding to a front portion, a middle portion, and a rear portion of the test mark, by reproducing the test mark; determining on whether the test mark has a desirable configuration or not, upon basis of at least one of ratios, defined between the amplitude of the front portion and the amplitude of the rear portion, and between the amplitude of the middle portion and the amplitude of the rear portion; correcting the write strategy if it is determined that the test mark has not the desirable configuration; and recording the information within the data area with the write strategy after the correction thereof.12-11-2008
20080285411OPTICAL DISK DRIVE - An optical disk drive capable of reproducing data even when warpage is present in an optical disk. A system controller of the optical disk drive reproduces data by setting a maximum speed in accordance with the type of an optical disk, an amount of side-to-side runout, or the like. In the meantime, when a read error arises as a result of trial reproduction being performed at an outer radius of the disk at startup, warpage is determined to be present in the optical disk, and a limitation on the maximum speed is raised. The rotational speed is set to allowable maximum speed of the optical disk drive, and warpage is corrected by means of centrifugal force. When reproduction becomes impracticable for reasons of meandering of a tack, or the like, during the course of reproduction of data, the rotational speed is decreased, to thus perform a retry.11-20-2008
20090003171Method and Device for Reading Data - The present invention relates to a method of reading data from a record carrier, the method comprising the steps of: obtaining a readout signal by radiating the record carrier in a first mode and a second mode of operation of a light source, computing a quality factor of the readout signal for the first mode and the second mode of operation of the light source, determining a best mode of operation of the light source based on the computed quality factors and selecting the determined best mode of operation of the light source for reading data from the record carrier. This is useful for high-speed Blu-ray disc applications.01-01-2009
20080198718RECORDING APPARATUS - A recording apparatus includes a write unit to write information data read from a memory by irradiating a disk medium with a beam in accordance with the information data, and a control unit to, upon the amount of information data stored in the memory reaching a threshold, instruct the write unit to start writing of the information data. In response to the write instruction, the write unit reads the information data stored in the memory and writes the read information data onto the disk medium while it is rotating. Upon the amount of information data in the memory decreasing to a predetermined value, the write unit stops reading and writing of the information data from the memory and onto the disk medium. The control unit sets a value of the threshold in accordance with the number of times the write unit has performed writing of the information data.08-21-2008
20110026388METHOD FOR CALIBRATION FOCUSING ERROR SIGNAL OF LIGHTSCRIBE DISC - A method for calibrating a focusing error signal of a lightscribe disc includes the following steps. An optical pickup head is moved to a focusing reference surface by utilizing radial voltages to some predetermined measuring positions to find and record the best gain value used to calibrate the asymmetry of the focusing error signal. The best gain fitting curve is formed by curve-fitting, based on the recorded radial voltages and the best gain values. The best gain value is obtained by an interpolation or extrapolation method, and used to calibrate the asymmetry of the focusing error signal of a lightscribe disc.02-03-2011
20100002556REPRODUCTION SIGNAL EVALUATION METHOD, REPRODUCTION SIGNAL EVALUATION UNIT, AND OPTICAL DISK DEVICE ADOPTING THE SAME - A reproduction signal evaluation method for evaluating quality of a reproduction signal reproduced from an information recording medium based on a binary signal generated from the reproduction signal using a PRML signal processing system, includes: a pattern extraction step of extracting, from the binary signal, a specific state transition pattern which has the possibility of causing a bit error; a step of computing a differential metric based on the binary signal; an extraction step of extracting the differential metric which is not greater than a predetermined signal processing threshold; a step of determining a mean value of the differential metrics which are not greater than the signal processing threshold and extracted in the extraction step; a standard deviation computing step of determining a standard deviation which corresponds to an error rate predicted from the mean value; and an evaluation step of evaluating a quality of the reproduction signal using the standard deviation.01-07-2010
20090316552Time interval analyzer which measures delay of read signal from medium - A time interval analyzer includes a phase comparator which decides whether a measured signal contains a delay quantity for either a positive delay or a negative delay relative to a characteristic value, and a processor circuit which outputs a ratio of a number of the measured signals containing the positive delay and a number of the measured signals containing the negative delay.12-24-2009
20090316551APPARATUS AND METHOD FOR WRITING DATA INTO STORAGE MEDIUM - An apparatus for writing encoded data into a storage medium includes a quality-check signal generator, a defect judgment unit and a verification unit. The quality-check signal generator is utilized for generating a quality-check signal; the defect judgment unit is coupled to the quality-check signal generator and is utilized for generating a defect judgment result according to the quality-check signal; and the verification unit is coupled to the defect judgment unit and is utilized for referring to the defect judgment result to selectively verify the encoded data that have been written into the storage medium.12-24-2009
20120195178OPTICAL 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 data record area of an optical recording medium which is loaded in the optical recording/reproducing apparatus; and a controller which allocates a specified area of the optical recording medium as a management information record area, controls the optical pickup to record the management information regarding the data being recorded in the data record area to be recorded in the management information record area, and controls the optical pickup to periodically record the management information of the management information record area onto a file information record area of the optical recording medium.08-02-2012
20100302925REPRODUCED SIGNAL EVALUATING METHOD, INFORMATION RECORDING MEDIUM, REPRODUCING DEVICE, AND RECORDING DEVICE - A reproduction signal evaluation method according to the present invention includes a step of generating a binary signal from an information recording medium on which a data sequence including marks and spaces in combination is recordable, using a PRML signal processing method from a signal obtained by reproducing the data sequence; and a differential calculation step of calculating a differential metric using a first state transition path having a maximum likelihood and a second state transition path having a second maximum likelihood, and a reproduction signal, the first state transition path and the second state transition path being obtained based on the binary signal. In a pattern including a shortest mark and a shortest space adjacent before or after the shortest mark, a shift amount of an edge of the shortest mark is obtained from a differential metric calculated regarding one of a first pattern in which a space adjacent to the shortest mark and not adjacent to the shortest space is longer than the shortest space; and a second pattern in which a mark adjacent to the shortest space and not adjacent to the shortest mark is longer than the shortest mark.12-02-2010
20110019520DATA RECORDING EVALUATING METHOD AND OPTICAL DISK RECORDING AND REPRODUCING DEVICE - A novel evaluation index is introduced so as to allow both a total evaluation of data recording and an evaluation of individual detection patterns. A data recording evaluation method includes a step of reproducing the result of data recording performed on an optical disk and identifying a predetermined detection pattern in a reproduction signal, a step of detecting the signal state of the reproduction signal corresponding to the predetermined detection pattern, and a first calculation step of calculating a first recording state evaluation index value based on the detected signal state and a reference condition which is identified from the predetermined detection pattern and adjusted so as to reflect the signal state of the reproduction signal. When there is a plurality of predetermined detection patterns, the method further includes a second calculation step of calculating a second recording state evaluation index value using the first recording state evaluation index value for each of the predetermined detection patterns. Data recording can be evaluated properly using the first and second recording state evaluation index values.01-27-2011
20100014405Method for Evaluating Quality of Read Signal And Apparatus for Reading Information - A most probable path is selected from a number n (where n≧2) of paths of state transitions occurring from a first state S01-21-2010
20110096651EVALUATION APPARATUS AND EVALUATION METHOD - An evaluation apparatus includes: a signal reading block; a first waveform equalization block; a boundary detection block; a selective output block; and an evaluation value generation block.04-28-2011
20090022026METHOD FOR CALIBRATING FOCUS LEVEL ON A LIGHT SCRIBE DISC - A method for calibrating a focus level on a light scribe disc includes driving a pick-up head with a predetermined speed in a predetermined direction to calibrate a focus level for a moving stage, detecting light summed signals along the light path of the moving stage, and finding and recording the maximum light summed signal and corresponding position of the pick-up head as the focus level for the moving stage. When a number of the moving stages is greater than a predetermined value, the focus level of the moving stage serves as the optimum focus level of the light scribe disc. When the number of moving stages is fewer, lowering the speed with a stage reduction and change the direction opposite to the predetermined direction, and proceeding to a next moving stage to calibrate the focus level.01-22-2009
20100322052REPRODUCTION SIGNAL QUALITY EVALUATION DEVICE AND METHOD - In a reproduction signal quality evaluation device, a pattern detector detects, from a code sequence obtained by PRML decoding, a predetermined pattern including a portion corresponding to a zero-cross point of a reproduction signal sequence obtained by PR equalization in PRML decoding. A distance difference calculator calculates a difference between the distances between the reproduction signal sequence and each of two ideal transition sequences of the reproduction signal sequence by computing an expression corresponding to the detected pattern using the value of a sample point of the reproduction signal sequence that is in a portion corresponding to the detected pattern and corresponds to a code relatively greatly weighted in an equalization expected value of a code sequence subsequent to the detected pattern. A dispersion calculator calculates a dispersion of the calculated distance difference.12-23-2010
20100097908REPRODUCTION SIGNAL EVALUATION METHOD, INFORMATION RECORDING MEDIUM, REPRODUCTION APPARATUS AND RECORDING APPARATUS - A reproduction signal evaluation method according to the present invention includes a step of generating a binary signal from an information recording medium on which a data sequence including marks and spaces in combination is recordable, using a PRML signal processing method from a signal obtained by reproducing the data sequence; and a differential calculation step of calculating a differential metric using a first state transition path having a maximum likelihood and a second state transition path having a second maximum likelihood, and a reproduction signal, the first state transition path and the second state transition path being obtained based on the binary signal. In a pattern including a shortest mark and a shortest space adjacent before or after the shortest mark, a shift amount of an edge of the shortest mark is obtained from a differential metric calculated regarding one of a first pattern in which a space adjacent to the shortest mark and not adjacent to the shortest space is longer than the shortest space; and a second pattern in which a mark adjacent to the shortest space and not adjacent to the shortest mark is longer than the shortest mark.04-22-2010
20100097909METHOD AND APPARATUS FOR DETECTING SPECIFIC SIGNAL PATTERN IN A SIGNAL READ FROM AN OPTICAL DISC - A signal pattern detecting apparatus, which is capable of detecting a physical mark in a read back signal being read from an optical disc, includes a matching signal generator, a signal comparing device, and a decision circuit. The matching signal generator is utilized for generating a matching signal, capable of being utilized to identify the physical mark, according to a reference clock and a wobble clock. The signal comparing device is electrically connected to the matching signal generator, and utilized for comparing the matching signal with a wobble data signal to generate a comparison signal. The decision circuit is electrically connected to the signal comparing device, and utilized for generating an indication signal according to the comparison signal and a threshold value. Both the wobble data signal and the wobble clock are derived from the read back signal.04-22-2010
20120201112REPRODUCTION SIGNAL EVALUATION METHOD, REPRODUCTION SIGNAL EVALUATION UNIT, AND OPTICAL DISK DEVICE ADOPTING THE SAME - A reproduction signal evaluation method evaluates the quality of a reproduction signal reproduced from an information recording medium based on a binary signal generated from the reproduction signal using a PRML signal processing system. A pattern extraction step extracts, from the binary signal, a specific state transition pattern which has the possibility of causing a bit error; a step computes a differential metric based on the binary signal; an extraction step extracts the differential metric which is not greater than a predetermined signal processing threshold; a step determines a mean value of the differential metrics which are not greater than the signal processing threshold and extracted in the extraction step; a standard deviation computing step determines a standard deviation which corresponds to an error rate predicted from the mean value; and an evaluation step evaluates a quality of the reproduction signal using the standard deviation.08-09-2012
20120170434INFORMATION RECORDER, INFORMATION REPRODUCER, RECORDING MEDIA MANUFACTURING SYSTEM, AND INFORMATION RECORDING MEDIA, METHOD AND PROGRAM - The present invention provides an information recording configuration that achieves both difficulty in reading and highly accurate reading. Highly confidential additional information such as encryption key is recorded in a groove signal. During recording of the additional information, a groove signal is recorded that has an amplitude offset setting commensurate with the bit value. During reading of the additional information, a signal R07-05-2012
20100322051Recording and reproducing apparatus, method of calculating temperature characteristic compensation operation coefficient, and reproducing apparatus - A recording and reproducing apparatus is provided, which includes a rotary drive unit, an optical pickup unit, an adjustment unit which compensates for changes in characteristics of the laser light caused by changes in temperature, a temperature detection unit which detects a temperature of the optical pickup unit, an evaluation value generation unit which generates an evaluation value based on reflected light information, and a control unit. The control unit performs a temperature acquisition process, an optimum point adjustment process, a temperature acquisition process for acquiring a detected temperature during spin down, an optimum point search process, and a temperature characteristic compensation operation coefficient calculation process for performing temperature compensation with respect to the adjustment values.12-23-2010
20100214895REPRODUCTION SIGNAL EVALUATION METHOD, REPRODUCTION SIGNAL EVALUATION UNIT, AND OPTICAL DISK DEVICE ADOPTING THE SAME - A reproduction signal evaluation unit has: a pattern detection section for extracting, from a binary signal, a specific state transition pattern which has a possibility of causing a bit error; a differential metric computing section for computing a differential metric based on the binary signal of the extracted state transition pattern; an error computing section for computing an error rate predicted based on an integration value that is integrated by an integration section, a count value that is counted by a pattern count section, an integration value that is integrated by another integration section, and a count value that is counted by another pattern count section, and a standard deviation computing section for computing a standard deviation based on the computed error rate.08-26-2010
20100195462METHOD OF EVALUATING REPRODUCE SIGNAL AND OPTICAL DISC DRIVE - A highly efficient and reliable reproduced signal evaluation method and an optical disc drive using that method in which assuming that the number of 2T's appearing successively in a predetermined evaluation bitstream is i, the evaluation bitstream is divided into a main bitstream (5+2i) long and sub bitstreams at the ends of the main bitstream. The check process to determine whether a predetermined evaluation bitstream is included in the binarized bitstreams is replaced with a main bitstream agreement check. This can prevent an increase in the circuit size. At the same time, by separately summing up for each main bitstream the calculated results of Euclidean distance between the reproduced signal and the target signal corresponding to the evaluation bitstream, the size of an evaluation summing circuit can be reduced.08-05-2010
20110188364OPTICAL DISC DRIVE AND TRACKING METHOD THEREOF - An optical disc drive and tracking method thereof are disclosed. The optical disc drive includes an optical pickup head, a slip compensation module, a tracking control module and a tracking drive. The optical pickup head generates a detected signal according to an optical signal from an optical disc. The slip compensation module generates a slip compensation signal according to the detected signal. The tracking control module generates a tracking out signal according to the detected signal and the slip compensation signal and, according to the tracking out signal, the tracking drive drives the optical pickup head.08-04-2011
20110051578METHOD FOR TESTING OPTICAL DISK DRIVE - The invention provides a method for testing an optical disk drive. The method comprises: resetting a successful number of a test and setting an upper limit for the successful number of the test; proceeding with a virtual writing by a laser beam with predetermined power; checking whether the output power is different from the predetermined power; if the output power is different from the predetermined power, determine the test fails, and if the output power is not different from the predetermined power, plus one to the successful number, wherein the optical disk drive passes the test when the number of successful test reaches the upper limit. The invention can reduce the time of testing the optical disk drive.03-03-2011
20110216639DETECTOR AND DETECTION METHOD - The present disclosure improves tracking characteristics of an envelope detected from an input signal to the input signal. A detector, which obtains an output signal from an input signal containing a target signal, and outputs the output signal, includes: a comparator configured to compare the input signal to the output signal, and output an obtained comparison result; and an envelope generator configured to weight a first value and a second value having a sign opposite to that of the first value in accordance with the comparison result, integrate the weighted first value and the weighted second value, and output an integral value as the output signal. The envelope generator includes a first gain generator configured to output the first value in accordance with an amplitude of the input signal.09-08-2011
20110305129RECORDING DEVICE, RECORDING METHOD, AND PROGRAM - A recording device includes: a recording and reproducing unit that records or reproduces data stored on a recording medium; and a control unit that interrupts recording during recording performed by the recording and reproducing unit, acquires an evaluation value of a recording quality of a recorded portion, changes recording speed based on the evaluation value, and resuming the recording.12-15-2011
20110075539 RECORDING MEDIUM RECORDING/REPRODUCING METHOD AND A RECORDING MEDIUM RECORDING/REPRODUCING APPARATUS - The present invention provides a recording medium reproducing method comprising the steps of: irradiating light onto a recording medium, the recording medium including a data image and a reference pattern, the reference pattern being divided by a plurality of fractional regions, the fractional regions being in invert, rotational and symmetrical relationship; determining information associated to data-image distortion based on the reference pattern; and correcting position of the data image based on the information relating to data-image distortion.03-31-2011
20080310275METHOD FOR DISPLAYING RESULT OF MEASUREMENT OF ECCENTRICITY - A method for displaying a result of measurement of eccentricity in an optical system is provided where an amount of eccentricity for each lens element's surface in a lens system can be displayed and where the amount of eccentricity displayed can be a magnified amount of eccentricity. Additionally a sectional view of the lens system can be displayed using scaling factor.12-18-2008
20120002526METHOD OF EVALUATING REPRODUCE SIGNAL AND OPTICAL DISC DEVICE - A highly efficient and reliable reproduced signal evaluation method and an optical disc drive using that method in which assuming that the number of 2T's appearing successively in a predetermined evaluation bitstream is i, the evaluation bitstream is divided into a main bitstream (5+2i) long and sub bitstreams at the ends of the main bitstream. The check process to determine whether a predetermined evaluation bitstream is included in the binarized bitstreams is replaced with a main bitstream agreement check. This can prevent an increase in the circuit size. At the same time, by separately summing up for each main bitstream the calculated results of Euclidean distance between the reproduced signal and the target signal corresponding to the evaluation bitstream, the size of an evaluation summing circuit can be reduced.01-05-2012
20110090778OPTICAL INFORMATION RECORDING METHOD, OPTICAL INFORMATION RECORDING DEVICE AND OPTICAL INFORMATION RECORDING MEDIUM - The present invention provides an optical information recording apparatus and method capable of effectively determining appropriate recording parameters in a short time with favorable efficiency, when recording information onto an optical disk having different information recording conditions and information recording characteristics. An information recording condition or an information recording characteristic of an optical disk 04-21-2011
20090135696OPTICAL DISC APPARATUS AND SELECTION METHOD FOR EVALUATION METHODS OF RECORDING QUALITY - An optical disc apparatus in which a β method using a β value showing asymmetry of an amplitude of a reproduction signal or a κ method using a modulation degree of the reproduction signal is executed as an evaluation method of evaluating recording quality of data in an optical disc, wherein: the data recorded by a recording power of a different intensity is reproduced; a β value and a jitter value are obtained on the basis of the reproduced data, respectively; the β method is selected as an evaluation method of evaluating the recording quality of the data in the optical disc under such a condition that the obtained β value satisfies a predetermined requirement for the recording power of the different intensity; and a target β value is set on the basis of the obtained jitter value when the β method has been selected.05-28-2009
20120250483WRITE POWER ADJUSTMENT METHOD AND INFORMATION RECORDING METHOD - In write power adjustment for an optical disc having a plurality of information storage layers, data of trial writing is varied by the influence of layers other than a target layer. It is difficult, therefore, to determine optimal write power. A modulation M[m] is obtained from a reproduction signal amplitude of a signal subjected to the trial writing performed with use of write powers Pw[m] (m being an integer) of a plurality of kinds. At least an optimum write power intercept Pint_opt is determined by fitting a relation between the Pw[m] and the M[m] by a modulation characteristic formula M=Masy×(1−(Pint−Pasy)/(Pw−Pasy)) having an asymptotic modulation Masy, a write power intercept Pint, and an asymptotic write power Pasy as parameters. Approximation accuracy by the fitting and/or quality of the trial writing signal are evaluated with use of at least the M[m], the modulation characteristic formula, and the Pint_opt. An optimum write power Pw_opt is calculated by performing a specified operation at least with use of the Pint_opt.10-04-2012
20100208561OPTICAL ACCESSING SYSTEM - An optical storage system includes an optical pick-up head for receiving and transforming an optical signal into an electric signal; a pre-amplifier for receiving the electric signal and outputting a RF signal and a position error signal; a data and timing recovery unit for receiving the RF signal and generating a modulated signal and a clock signal; an error correction unit for generating a data signal according to the modulation signal and the clock signal; a defect signal generator for receiving the RF signal and generating a defect signal according to the RF signal, wherein the defect signal is enabled when the RF signal has a defect; and an error correction controller for receiving the defect signal and generating an error correction control signal according to the defect signal, wherein the error correction unit further receives the error correction control signal and adjusts the decoding strategy of the error correction unit according to the error correction control signal.08-19-2010
20110158071WRITE STRATEGY DETERMINING METHOD, OPTICAL DISC RECORDING METHOD, OPTICAL DISC AND OPTICAL DISC APPARATUS - An optical disc recording method of suppressing variations in the record quality due to variations in an initial strategy of a write strategy using many parameters corresponding to a next-generation large-capacity optical disc. Modulation conditions for recorded data on the optical disc are determined based on a real measurement thereof; an initial strategy that meets the modulation conditions is determined; an optical strategy is determined in which the record quality is best in the vicinity of the initial strategy; and data is recorded on the optical disc, using the optimal strategy.06-30-2011
20120243392RECORDING ADJUSTING METHOD, INFORMATION RECORDING AND REPRODUCING DEVICE, AND INFORMATION RECORDING MEDIUM - The present invention achieves tracking servo using a recording signal on a grooveless optical disc. Trial writing signals are written by using multiple recording conditions, and a recommended recording condition having favorable qualities of a reproduction signal and a tracking error signal is determined based on the trial writing signals. Then, recording is performed by using the recommended recording condition. In addition, by using a recording condition determined based on an optimum power control performed prior to the recording, signals are recorded adjacent to each other in at least two tracks. Signals are recorded by using the determined recording condition under which a tracking error signal quality obtained from the recording signal matches a desired value of a tracking error signal quality of the medium.09-27-2012
20100315927WRITE SPLICE FOR OPTICAL RECORDING CHANNELS - An enhanced write splice for optical recording channels is disclosed. Optical control circuitry locks to previously-written data and determines the estimated write splice location. A training sequence is written to the optical medium at a location based on the estimated write splice location. The phase offset is then estimated by reading the training sequence. A new write splice location may then be calculated compensating for the phase offset estimate. Finally, the new data to be spliced may be written or overwritten to the channel at the new write splice location.12-16-2010
20120281514METHOD AND SYSTEM FOR EQUALIZING HOLOGRAPHIC DATA PAGES - Methods and systems for equalizing a holographic image page and for compensating nonlinearity of a holographic data storage channel are disclosed. In one embodiment, a method for equalizing a holographic image page includes receiving the holographic image page and dividing the holographic image page into a plurality of local image regions. The method further includes generating a local alignment error vector for each local image region, computing a local finite impulse response kernel for each local image region according to the corresponding local alignment error vector, and adjusting misaligned pixels of each local image region using the corresponding local finite impulse response kernel.11-08-2012
20110310719OPTICAL INFORMATION REPRODUCING DEVICE, OPTICAL INFORMATION REPRODUCING METHOD AND INTEGRATED CIRCUIT - An optical information reproducing device is provided with a light focusing unit (12-22-2011
20120087223METHOD OF WRITING DATA TO A DISC, DISC DRIVE - The invention relates to a method of writing data to a disc (OD). The method comprised: a) performing a plurality of writing actions in which a plurality of data portions are written to the disc, b) performing a plurality of verification actions in which written data portions are at least partly verified and at least part of the data portions are replaced if needed. The method further comprises a2) performing a decision action for each writing action in which a decision whether or not to perform the verification action for a specific written data portion is taken.04-12-2012

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