Abstract: An exemplary method for recording a first mark with a first length and a second mark with a second length onto an optical storage medium includes: when recording of the first mark requires a power transition from a first laser power level to a second laser power level, making a specific control signal have a logic transition from a low logic value to a high logic value and other control signals have no logic transition; and when recording of the second mark requires a power transition from a third laser power level to a fourth laser power level, making the specific control signal have the logic transition from the low logic value to the high logic value and other control signals have no logic transition.

Abstract: A method for tuning a write strategy parameter of an optical storage device, includes: writing a segment of data according to a plurality of write strategies; reading the data back and detecting a plurality of lengths, each length corresponding to a pit or a land on an optical storage medium accessed by the optical storage device; performing calculations according to the lengths and a plurality of data types to generate a plurality of calculation results, each of the data types corresponding to at least a specific target pit length or at least a specific target land length; and utilizing the calculation results to determine a proper write strategy.

Abstract: Provided is a recording apparatus including a self-excited oscillation semiconductor laser that has a double quantum well separate confinement heterostructure and includes a saturable absorber section to which a negative bias voltage is applied and a gain section into which a gain current is injected, an optical separation unit, an objective lens, a light reception element, a pulse detection unit, a reference signal generation unit, a phase comparison unit, a recording signal generation unit, and a control unit.

Abstract: An optical disk recording method includes the steps of: providing a multi-pulse chain from a recording wave; independently changing the pulse rise timing and pulse fall timing (pulse width) of the first pulse in the multi-pulse chain in accordance with a preceding space length and a recording mark length; changing the pulse rise timing and pulse fall timing (pulse width) in accordance with a following space length and the recording mark length in a predetermined timing or in independence; and in relation to the smallest mark recorded by irradiation with mono pulse, changing the rise timing in accordance with the preceding space length and the recording mark length and the fall timing (pulse width) in accordance with the following space length and recording mark length, compensating various optical disks different in recording material without change of the fundamental waveform.

Abstract: An optical recording method includes the steps of: encoding record data to generate encoded data which is a combination of marks and spaces; classifying the encoded data according to a combination of a mark length of the mark, a space length of a first space that immediately precedes the mark, and a space length of a second space that immediately succeeds the mark; generating a write pulse train for forming the mark, in which at least one of a leading end edge position, a trailing end edge position and a pulse width of the write pulse train is changed according to a classification result; and irradiating the optical disc medium with the write pulse train generated to form the plurality of marks on the optical disc medium.

Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.

Abstract: A method of controlling a laser driver includes determining a set of timing parameters in response to contents of a received bit stream. The method further includes creating a plurality of sets of pulse defining parameters in response to the set of timing parameters, and generating a plurality of generic pulses in response to the plurality of sets of pulse defining parameters. The method also includes combining the plurality of generic pulses into a plurality of enable signals, and creating a plurality of adapted enable signals by selectively replacing one of the plurality of enable signals with an alternative signal. The method further includes outputting the plurality of adapted enable signals to the laser driver.

Abstract: Aspects of the disclosure can provide a method to optimize optical recording. The method can include recording a pre-defined pattern on an optical medium according to a first write strategy, measuring edge timings corresponding to the pre-defined pattern recorded on the optical medium, determining a second write strategy including at least timing modifications to the first write strategy. The timing modifications can be determined based on means and variances of the measured edge timings, edge timing means and variances targets for desired edge timings, and edge timing sensitivities to the timing modifications.

Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.

Abstract: Disclosed herein is a laser driving apparatus, including: a driving unit adapted to current drive a laser device with a current value in accordance with a level of a signal supplied thereto; and an emission light waveform correction unit adapted to receive supply of a pulsed reference signal and generate, based on a correction timing pulse interlocked with a rising edge and/or a falling edge of a pulse, a correction signal having a level different from that of the reference signal and then supply the correction signal to the driving unit so that the shape of the emission light waveform of the laser device becomes close to that of a rectangular wave.

Abstract: An energy converter includes magnetic coils of N phases (N is an integer of 3 or more), and a PWM drive circuit for driving the magnetic coils of N phases, wherein the magnetic coil of each phase can be independently controlled by the PWM drive circuit.

Abstract: In a medium of the phase change type, a power ratio and modulation degree for use in recording are determined from a recommended pulse width value in the recommended write strategy parameters recorded in the optical disk, the recommended power ratio value, the recommended recording power value, and the characteristics of the optical recording device, and recording is carried out on the optical disk according to the power ratio value and modulation degree value thus determined. Optimal recording can be carried out even on an optical disk for which the optimal write strategy information has not been determined in advance, without the need to store write strategy information suitable for each and every optical disk.

Abstract: An optical recording medium is provided, the optical recording medium including a plurality of zones respectively corresponding to width data of first and/or last pulses of an adaptive write pulse waveform stored in a grouping table, the grouping table being configured to group a magnitude of a present mark of input data and magnitudes of leading and/or trailing spaces of the present mark into a short pulse group, a middle pulse group, and a long pulse group using grouping pointers, store data configured to calculate a width of a write pulse, an adaptive write pulse being generated in response to the calculated width, generate the adaptive write pulse waveform by varying a position of a rising edge of a first pulse of a mark to be written according to the magnitudes of the present mark and the leading space, the adaptive write pulse waveform being generated without regard for the trailing space of the present mark being written using the adaptive write pulse waveform, the adaptive write pulse being configured

Abstract: An optical recording medium is provided, the optical recording medium including a plurality of zones configured to store data corresponding to an adaptive write pulse, the adaptive write pulse including a first pulse, a last pulse, and a multi-pulse train, the adaptive write pulse being different for each of the plurality of zones, the plurality of zones being reflected by a grouping table, the grouping table being configured to generate an adaptive write pulse waveform by varying a position of a rising edge of a first pulse of a mark to be written according to a length of the mark to be written and a leading space, the adaptive write pulse waveform being generated without regard for a trailing space of a present mark being written using the adaptive write pulse waveform, the adaptive write pulse being configured to correspond to the adaptive write pulse waveform, and store rising edge data of the first pulse of the adaptive write pulse waveform varying according to corresponding stored values of lengths of m

Abstract: An apparatus configured to write input data on an optical recording medium using a write pulse waveform including a first pulse, a last pulse and a multi-pulse train is provided.

Abstract: An information recording medium having a disc shape and a recording layer configured to store information by light, the information being configured to be recorded on the recording layer with a mark and a space, wherein a channel clock period, represented by T, is provided for recording the mark on the recording layer. A mark corresponding to 2T or more can be recorded, and write parameter information is recorded on a particular area of the information recording medium. The parameter information includes a first peak power value used for a standard recording speed, and a second peak power value used for an increased recording speed which is a quadruple of the standard recording speed, the second peak power value being greater than the first peak power value.

Abstract: A recording medium having a data structure of a control information recorded on the recording medium or to be recorded/reproduced on/from the recording medium, characterized in that the control information is associated with a specific recording velocity and the control information includes write strategy information dependent on a type information indicating whether the control information is associated with CAV mode or CLV mode.

Abstract: An optical disc drive according to the present invention includes an optical pickup and a writing control section for instructing the optical pickup to record a mark, representing the information to be written, on the optical disc. In recording the mark on the optical disc, the writing control section instructs the optical pickup to irradiate the same area on the optical disc with a light beam a plurality of times so that the mark is recorded in that repeatedly irradiated area.

Abstract: An apparatus configured to write input data on an optical recording medium using a write pulse waveform, the write pulse waveform including a first pulse, a last pulse and a multi-pulse train, is provided.

Abstract: A recording and reproducing apparatus includes: an optical head unit irradiating a laser beam on an optical recording medium and performing writing and readout of information represented by marks and spaces on the medium; a laser-driving-pulse generating unit generating and supplying a laser driving pulse to the head unit, and causing the head unit to execute laser beam irradiation; an evaluation-value measuring unit measuring an evaluation value representing an error of an edge position of the mark; and a control and calculating unit causing the apparatus to separately execute, concerning mark lengths to be adjusted among mark lengths of the laser driving pulse, for each set of mark lengths grouped in advance, trial writing with shift amounts of edge positions of a laser driving pulse concerning the lengths belonging to the set changed, causing the apparatus to execute readout of a signal recorded by the execution of the trial writing, causing the measuring unit to measure an evaluation value under setting o

Abstract: There is provided an optical recording method for directing a recording pulse train to an optical disc medium to form marks thereon and for recording information as information about the edge positions of said marks and the spaces between marks, the recording pulse train having been created by modulating laser light into plural power levels. The method includes: coding to-be-recorded data into coded data consisting of the combination of marks and spaces; classifying said marks within said coded data on the basis of the mark length and the preceding or succeeding space lengths of the marks; shifting the position of the second pulse edge counted from the end portion of the recording pulse train for forming said marks, depending on the result of said classification, to adjust said recording pulse train; and directing said recording pulse train to the optical disc medium to form said marks thereon.

Abstract: An information recording medium according to the present invention includes a track on which a data sequence including a plurality of recording marks and a plurality of spaces provided between the plurality of recording marks is recordable; and a recording condition recording area in which a recording condition for recording the data sequence on the track is recordable.

Abstract: An optical disk apparatus is provided that has a signal processing circuit for equalizing a signal so as to achieve predetermined equalization, in which interference between codes is permitted, by means of an adaptive equalization circuit or the like, and for performing binarization by means of a maximum likelihood decoding circuit in which interference is performed as a rule, and thereby achieves stabilized signal reproduction in a narrow-band transmission. When evaluating the quality of the recorded signal through the use of the recording parameter learning and the reproduction system such as recorded signal verification, the optical disk recording apparatus is capable of highly precisely evaluating the quality of the recorded signal by fixing a circuit characteristic after suspending the optimization operation of the adaptive equalization circuit or the like for optimizing the characteristic by the reproduced signal. An optical disk recording method is also provided.

Abstract: When a phase shift is to be evaluated, based on a difference between an output from a waveform equalization circuit to equalize an input reproduced signal to a predetermined target equalization characteristic and the target equalization characteristic, the phase shift of the reproduced signal relative to a channel clock, a group delay characteristic with respect to the frequency of the waveform equalization circuit is fixed. Hence, an equalized waveform as an output from the waveform equalization circuit can preserve phase shift information of the inputted reproduced signal to correctly detect the phase shift of the reproduced waveform using the equalized waveform. It is hence possible to realize, with high precision, optimal value learning of various parameters for the recording, reproduction, and servo by use of the phase shift as an index.

Abstract: An optical recording method for recording information by irradiating an optical disc medium with a modulated write pulse train of laser light variable over a plurality of power levels such that a plurality of marks are formed on the optical disc medium, edge positions of each of the marks and a space between adjacent two of the marks being utilized for recording of the information.

Abstract: In an optimal recording power calibration method for improving seeking stability on a recording power calibration area, a specific area serves as a data recording area during an optimal recording power calibration, wherein a length of the specific area is such that a plurality of times of optimal recording power calibrations can be performed. The method includes: an optimal recording power calibration step of recording, with different recording power, a first length of calibration data in the specific area, and calibrating optimal recording power, wherein a data sector recorded in this step is defined as a calibration recording sector; and a data recording step of recording, with data recording power, a second length of information having a logical address beside the calibration recording sector of the specific area, wherein a data sector recorded in the step is defined as an information recording sector.

Abstract: In the related art, writing of BCA data has been performed by a BCA cutter or the like after a user data area was formed. However, according to such a method, individual steps cannot help being provided for a disc manufacturing step in order to form the BCA. A burden on the disc manufacturer is large from a viewpoint of the number of disc producing steps and, further, manufacturing costs. By using a bit forming method similar to a user data area, the BCA manufacturing steps can be reduced. Specifically speaking, by devising a pit depth, a pit width, and a pit pattern, a modulation degree of a BCA portion can be further increased. A detecting method similar to that for the BCA in the related art can be applied.

Abstract: An optical disc device and an adjusting method for a recording condition for use with the optical disc device that records data into an optical disc medium by using codes whose shortest run length is 2T and reproduces the recorded data by using an adaptive equalizing procedure and a PRML procedure, wherein the recording condition is so adjusted that a reproduced signal with desired quality can be obtained, by using, as the adaptive equalizing procedure, a procedure in which a tap coefficient Cn is set to a value obtained by averaging values of a tap coefficient an renewed by a LMS method, located symmetrically with each other along the time axis.

Abstract: A sync mark detector for detecting a sync mark having alternative polarities includes an input terminal receiving data bits, wherein the data bits include constant bit groups and each constant bit group includes consecutive bits of the same logic value, the first unit outputting constant bit length values that are representative of bit lengths of constant bit groups, respectively, the second unit outputting combined bit length values, wherein each combined bit length value is representative of a sum of two consecutive constant bit length values, the third unit comparing each combined bit length value to a largest previous combined bit length value to determine a largest combined bit length value, the fourth unit determining a threshold value based on the largest combined bit length value, and the fifth unit outputting a sync mark detection signal when an individual combined bit length value is larger than the threshold value.

Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.

Abstract: A semiconductor device mounted in an optical disk apparatus controls writing and reading of data in and from an optical disk. The device performs first processing for adjusting a write strategy in such a manner that based on error information corresponding to a shift in the phase of a reproduction signal with respect to a channel clock signal for data reproduction, which is generated based on the reproduction signal read from the optical disk, the value of the error information related to a plurality of recording marks to be evaluated becomes minimum as a whole. The device also performs second processing for adjusting a write strategy in such a manner that the value of the error information related to a desired recording mark becomes small.

Abstract: An information recording medium, comprising N number (N is an integer fulfilling N?3) of information layers on which information is recordable, and allowing information to be recorded on each of the information layers and allowing information recorded on each of the information layers to be reproduced by being irradiated with laser light. The N number of information layers include an N'th information layer, an (N?1)th information layer, an (N?2)th information layer, . . . a second information layer and a first information layer sequentially located from a laser light incidence side. A reflectance of the N'th information layer is RN, and a reflectance of an M'th information layer (M refers to every integer fulfilling N>M?1) is RM.

Abstract: An energy converter includes magnetic coils of N phases (N is an integer of 3 or more), and a PWM drive circuit for driving the magnetic coils of N phases, wherein the magnetic coil of each phase can be independently controlled by the PWM drive circuit.

Abstract: A recording parameter setting device setting parameters of pulse sequences forming recording marks on recording media. The device includes a storage section storing first and second look-up tables, and a recording parameter setting section for obtaining from the tables and setting parameters corresponding to recording information. The pulse sequences form at least marks equal to or longer than a first predetermined length but not longer than a maximum mark length, and include top and last sections. Also, the first lookup table stores parameters for top sections that control heat of front edges of marks classified into a same group. The second lookup table stores parameters for last sections for controlling heat of rear edges that are equal to or longer than a second predetermined recording mark length, that is longer than the first predetermined recording mark length, through the maximum recording mark length and classified into a same group.

Abstract: In order to ensure a favorable recording characteristic for a write-once recording medium whose recording layer is made of an organic dye having an absorption spectrum at a wavelength ?=405 nm, this optical information recording apparatus includes a unit to set a write power to form recording marks, a space forming power to form spaces and a pulse width of a cooling pulse, and a unit to record information onto the recording medium according to the setting. The pulse width of the cooling pulse and a ratio of the space recording power to the write power are determined from a favorable region in a plane whose one coordinate axis represents the ratio and whose other coordinate axis represents the pulse width of the cooling pulse.

Abstract: A recording apparatus includes a rotation driving portion that rotates and drives an optical disc master; and a recording portion that performs an information recording on the optical disc master, by performing a laser beam irradiation on the optical disc master, based on a recording waveform which has a land pulse of a first power, a recording waveform portion having a recording pulse of a second power higher than the first power, and a cooling pulse which has a third power lower than the first power and is inserted between the land pulse and the recording waveform portion.

Abstract: A reproduction signal evaluation method according to the present invention relates to adjustment of an edge portion between a shortest mark and a shortest space in a data sequence including marks and spaces in combination that is recordable on an information recording medium. 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.

Abstract: An optical recording medium including a plurality of recording layers to record/reproduce information using light with a predetermined wavelength, the information being recorded on one of the recording layers using a mark and a space, wherein a channel clock period T is provided for recording the mark on one of the recording layers. A plurality of pulses, including a last pulse arranged at an end of the pulses, are used to record the mark with length 3T, the mark being recorded with a condition that a width of the last pulse is minimum OT and maximum 1.10T, in which a first subsequent level lower than a peak power level of the last pulse is arranged next to the last pulse, and a second subsequent level lower than the peak power level but higher than the first subsequent level is arranged next to the first subsequent level.

Abstract: According to one embodiment, a re-recordable write-once optical disc by which recording/reproducing can be properly done with a short-wavelength blue laser is provided. The disc has recording layers on which marks are recorded by the laser power of a modulated short wavelength, with a space formed between the recorded marks. The recording layer of the disc uses an organic dye material by which no physical modification or no physical change substantially occurs in an area of the recorded marks.

Abstract: There is provided an optical recording method for directing a recording pulse train to an optical disc medium to form marks thereon and for recording information as information about the edge positions of said marks and the spaces between marks, the recording pulse train having been created by modulating laser light into plural power levels. The method includes: coding to-be-recorded data into coded data consisting of the combination of marks and spaces; classifying said marks within said coded data on the basis of the mark length and the preceding or succeeding space lengths of the marks; shifting the position of the second pulse edge counted from the end portion of the recording pulse train for forming said marks, depending on the result of said classification, to adjust said recording pulse train; and directing said recording pulse train to the optical disc medium to form said marks thereon.

Abstract: The present invention provides a measure for getting read/write control information stored within a space of a predetermined size in a format that ensures compatibility with media of a lower order or an older generation even if the size of the read/write control information increases significantly as the storage densities of information storage media rise in the near future. On an information storage medium, a data sequence is writable as a combination of marks and spaces. The medium has at least one information storage layer, which has an information storage area to store information and a control information area for use to perform a read/write operation on the at least one information storage layer. The control information area stores at least one set of control information, which includes a first kind of write pulse information including information to be used as a reference value and a second kind of write pulse information including information to be used as an offset value.

Abstract: An optical recording method includes the steps of: encoding record data to generate encoded data which is a combination of marks and spaces; classifying the encoded data according to a combination of a mark length of the mark, a space length of a first space that immediately precedes the mark, and a space length of a second space that immediately succeeds the mark; generating a write pulse train for forming the mark, in which at least one of a leading end edge position, a trailing end edge position and a pulse width of the write pulse train is changed according to a classification result; and irradiating the optical disc medium with the write pulse train generated to form the plurality of marks on the optical disc medium.

Abstract: 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.

Abstract: A laser driving device includes a storage unit that stores signal patterns for recording-waveform control representing level information of each divided driving signal to drive a laser device on a space and a mark based on the divided driving signals. Also, it includes a pulse generator that generates the reference pulse and the switching pulse based on a first transmission signal and a second transmission signal. The first transmission signal contains timing information for acquiring a reference pulse that represents a timing of repetitively switching between the space and the mark. The second transmission signal contains timing information for acquiring a switch pulse that represents a timing of switching the signals. Among level information for each of the signals in the storage, reference level information is read together with the reference pulse. Other level information after the reference level information is sequentially read for each switching pulse.

Abstract: According to a method of the present invention for recording data on an optical disk, a recording pulse corresponding to a long mark includes a combination of a leading pulse and a subsequent intermediate pulse. Further, a level of the leading pulse indicates a first recording power, and a level of the intermediate pulse indicates a second recording power. When an optical disk includes a plurality of recording layers, a ratio of the second recording power to the first recording power is determined for each recording layer. When the recording speed is variable, the ratio of the second recording power to the first recording power is determined for each recording speed.

Abstract: According to one embodiment, single-sided dual-layer recordable disc 100 may be used. Information recording is performed by forming mark and space portions on data area DA using modulated laser power. Pp denotes the maximum laser power or peak power for forming the mark portion, and Pb denotes the bias power for forming the space portion. Power ratio Pb/Pp is calculated for each of recording layers L0 and L1. Information is recorded on any of the recording layers L0 and L1 based on the result of calculation. Here, the calculated power ratio Pb/Pp changes among the recording layers L0 and L1, thereby optimizing the recording condition for a multi-layer recordable optical disc within relatively short time.

Abstract: With a large capacity of an optical disk and high-speed recording, a frequency of a recording signal is increased and a pulse width is narrowed. In the case that a laser is driven by a signal having the short pulse width, unfortunately the high-speed recording is hardly performed to an optical disk when a rise time and a fall time of the optical pulse are lengthened. During user data recording, a bottom driving current is set to a second bottom driving current value that is a current value of a threshold or less, so that the rise time and the fall time of the optical pulse can be shortened to perform the high-speed recording of the optical disk.

Abstract: A recording method suitable for high-density recording is provided to increase the reproduction quality. An optical information recording method is for recording information on an optical recording medium by irradiation of a write pulse of a laser beam to perform reproduction in a production system using a PRML detection scheme. The method includes recording a recording mark by a single write pulse, when the total length of the recording mark to be recorded and a space adjacent to the recording mark is less than a diameter of an effective reproduction spot, being 0.82×(?/NA), where ? is a wavelength of a reproduction laser beam and NA is a numerical aperture.

Abstract: A method and apparatus for writing data to an optical storage medium are disclosed. A write signal indicating power levels of a laser diode is generated by encoding and decoding codewords. The codewords are generated and decoded according to a specific requirement proposed by the present invention. By doing so, toggling (i.e. state changing) times occurring in channels transferring the codewords can be significantly reduced to avoid the problems of pulse distortion and disappearance in high frequency transmission. Alternatively, toggles appearing in the respective channels can be spread to avoid interference between the channels. Further, a phase adjustment device for adjusting a phase of each codeword is disclosed.

Abstract: It is desired that the overshooting and undershooting of optical pulse waveforms of optical pickups included in optical disk devices be reduced to improve the quality of recording. Among pulses to be recorded, the trailing edge of each last pulse and the leading edge of the subsequent erase top pulse are made to almost coincide with each other. Ratio a/b, where a is the difference between erase top pulse power level Pet and erasing power level Pe and b is the difference between recording power level Pw and the erasing power level Pe, is adjusted to realize an optical pulse waveform with reduced overshooting and undershooting for each of different recording media. Erase top pulse duration Tert is switched according to different recording speeds for different recording media.