Abstract: A recording method is provided, which comprises the steps of (a) generating a plurality of pulse sequences corresponding to a plurality of linear velocities, (b) while rotating a recording medium with a linear velocity selected from the plurality of linear velocities, forming at least one of a recording mark and a space by irradiating the recording medium with a pulse sequence selected from the plurality of pulse sequences, the pulse corresponding to the linear velocity. The step (a) comprises the steps of (a-1) measuring at least one first recording parameter corresponding to at least one linear velocity selected from the plurality of linear velocities, (a-2) determining a second recording parameter corresponding to the plurality of linear velocities based on the at least one first recording parameter measured, and (a-3) generating the plurality of pulse sequences corresponding to the plurality of linear velocities based on the second recording parameter measured.

Abstract: A recording method suitable for high-density recording is provided. When information is recorded on an optical recording medium with irradiation of a write pulse of a laser beam, a length corresponding to 7 T is set to be equal to or less than the spot diameter ?/NA of the laser beam where T is one recording clock cycle, ? is a wavelength of the laser beam, and NA is a numerical aperture of the objective lens, and a specified mark with a length corresponding to 3 T or more is recorded by a single write pulse.

Abstract: Provided herein are hybrid laser diode drivers (LDDs) that drive a laser diode in response to receiving enable signals from a controller. In accordance with specific embodiments, a hybrid LDD includes a read channel to selectively output a read current, one or more write channel each to selectively output a write current, and an oscillator channel to selectively output an oscillator current. Additionally, in specific embodiments the hybrid LDD includes a decoder that receives the enable signals from the controller, and based on the enable signals, controls timing of the currents output by the read, write and oscillator channels.

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: 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 0T 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 the present invention, there is provided a method of recording a unique ID to a read-only optical disc based on the 17PP modulation. The read-only optical disc (1) has set thereon a specific physical cluster to which a unique ID is to be recorded. With user data to be recorded to the specific physical cluster being made all zero (0), a pit/land pattern is formed, and a molding machine using a molding die is used to form many optical discs in the common manner. Thereafter, an ID unique to each optical disc is generated, and a land in a predetermined position in the specific physical cluster is transited to a pit by irradiating high-power laser light to the land correspondingly to the bit information, so that the pit/land pattern will comply the 17PP modulation rule even after the transition of the land to the pit.

Abstract: A write power adjustment method makes it possible to set optimum write power with high precision. Trial writing is conducted by using write power Pw,m (where m is an integer) of a plurality of kinds, and a modulation M,m associated with each write power is calculated. Optimum asymptotic power Pasy-opt is calculated by performing predetermined computation by using reference asymptotic power Pasy-ref and reference write start power Pws-ref which are previously determined for each medium. An evaluated value S,m=M,m×(Pw,m?Pasy-opt) is calculated by using the optimum asymptotic power Pasy-opt. Write power Pw that makes the evaluated value S equal to zero when applying straight line approximation to a relation between the write power Pw,m and the evaluated value S,m is calculated as optimum write start power Pws-opt. And optimum write power Pw-opt is found by performing predetermined computation on the optimum write start power Pws-opt.

Abstract: An optical storage system modulates a laser beam based on a high frequency modulation (HFM) signal and a pattern to be recorded on an optical storage medium. At least one of an amplitude and a frequency of the HFM signal is adjusted when using the light beam to record the pattern on the optical storage medium or read data from the medium.

Abstract: A device and method of recording marks representing data in an information layer of a record carrier includes irradiating the information layer by a pulsed radiation beam, each mark being written by a sequence of pulses. The recorded marks are erasable by irradiating the information layer with an erase radiation beam. The erase radiation beam has a first erase power level (e1) for a first erase period (t1), a second erase power level (e2) higher than or equal to the first erase power level (e1) for a second erase period (t2), and a third erase power level (e3) lower than the second erase power level (e2) for a third erase period (t3).

Abstract: A system includes an encoding module and a laser driver module. The encoding module is configured to encode a data stream. The laser driver module is configured to convert the encoded data stream into a write signal including one or more edges. The write signal is output to an optical writer. The laser driver module is configured to adjust an actual position at which the optical writer writes a first edge of the one or more edges on an optical storage medium away from a desired position for the first edge. The adjustment is made based on (i) a first preceding edge position, (ii) a first following edge position, (iii) a second preceding edge position or a second following edge position, and (iv) a third preceding edge position or a third following edge position. The first edge corresponds to a beginning of a mark edge of the write signal.

Abstract: In pulse width control equalization, attention is paid to the existence of the symmetry of anteroposterior signals and thereby the size of a table in which the adjustment amount of an edge position is stored is reduced to the power of one-half. Pattern jitters caused by inter-symbol interference are suppressed. The pulse time span of each symbol is adjusted to an optimum pulse width determined by a calculating formula or search in a table in response to a code sequence to be transmitted. In the configuration wherein a table is used, the table to store an edge position adjustment amount wherein the row of the exclusive OR of two symbols located at positions symmetrical to each other before and after a center symbol now ready to be sent in the code sequence is used as a search key is made.

Abstract: An optical disc apparatus capable of improving an overwrite performance for performing an overwrite operation on a re-writable type optical disc. The apparatus includes a calculating section which calculates out a recording power at the time of previously performing recording in a recording area of the optical disc, and a recording power determining section which determines a write power of the recording power calculated out by the calculating section as a write power of the currently recorded recording power, and at the same time, adjusts erase power, cooling power, and/or middle power of the recording power calculated out by the calculating section to finally determine the currently recorded recording power.

Abstract: The present invention is aimed at providing an optical disc device and a recording condition setting method which can automatically determine an optical recording condition to an optical disc, and the optical disc device comprises an optical pickup which records data on a disc; a data encoder which modulates data to be recorded; a recording timing setting means which sets a timing of recording the data on the disc; a phase error detection means which measures an error amount of a mark recorded on the disc from a position where the mark should be properly located; an error convergence means which calculates error information indicating an optimum position of the mark; a recording timing calculation means which calculates a correction value of the recording timing to be set on the recording timing setting means, based on the error information; and a control means which feedbacks an output of the recording timing calculation means to the recording timing setting means, thereby to optimize the recording timing.

Abstract: A hybrid LDD includes a read channel to selectively output a read current, a plurality of write channels, each to selectively output a different write current, and an oscillator channel to selectively output an oscillator current. Additionally, the hybrid LDD includes programmable LDD controller that receives the plurality of enable signals from the external controller, and based on the enable signals, controls timing of the currents output by at least the write channels. The programmable LDD controller can also control timing of the currents output by the read and oscillator channels, based on the enable signals. Further and alternative embodiments are also provided.

Abstract: A recording/reproducing device includes an optical head unit which performs writing and reading of information expressed by marks and spaces on an optical recording medium by irradiating laser light onto the optical recording medium, a laser driving pulse generating unit that generates a laser driving pulse according to the recorded information to supply a laser driving signal to the optical head unit, and executes the irradiation of the laser light onto the optical head unit for recording, an evaluation value calculating unit that calculates a quality evaluation value, which is an index of recording signal quality based on a signal read from the optical recording medium by the optical head unit, and an adjustment controlling unit that performs an adjustment setting of the laser driving pulse generated in the laser driving pulse generating unit.

Abstract: The optical data recording method comprising the steps of: modulating data to be recorded, to generate a plurality of recording modulation codes; and emitting a pulse-like light beam to an optical disc, so that a plurality of recording marks and spaces which have lengths corresponding to the plurality of recording modulation codes are formed on the optical disc. In the optical data recording method, at least two of the plurality of recording marks comprises: a first pulse which is disposed at a front and forms a leading edge of the recording mark, a last pulse which is disposed at a backend and forms a trailing edge of the recording mark, and a multi-pulse train which is disposed between the first pulse and the last pulse and forms a center of the recording mark. The multi-pulse train has a pulse period longer than T which represents a reference period of the recording modulation code.

Abstract: An optical recording medium is provided for allowing data to be recorded on, erased from, and reproduced from, and storing information about power levels of an erase pulse. The recorded erase pattern information may include information about power levels of first and last pulses of an erase pattern for erasing data. The first and last pulses of the erase pattern can be differently set depending on the differing kind of recording layer or layers of a disk or differing kinds of disks and recorded in a reproducible only area or rewritable area of the optical recording medium. Thus, by presetting the appropriate erase power levels, the time required for selecting an optimal erase power for the optical recording medium can be considerably reduced.

Abstract: A hybrid LDD includes a read channel to selectively output a read current, a plurality of write channels, each to selectively output a different write current, and an oscillator channel to selectively output an oscillator current. Additionally, the hybrid LDD includes programmable LDD controller that receives the plurality of enable signals from the external controller, and based on the enable signals, controls timing of the currents output by at least the write channels. The programmable LDD controller can also control timing of the currents output by the read and oscillator channels, based on the enable signals. Further and alternative embodiments are also provided.

Abstract: An information reproducing apparatus (1) is provided with: a correcting device (18) for correcting waveform distortion occurring in a read signal corresponding to a long mark, of read signal (RRF) read from a recording medium (100); an amplitude limiting device (182) for limiting an amplitude level of the read signal in which the waveform distortion is corrected, by a predetermined amplitude limit value (L, ?L), thereby obtaining an amplitude limit signal; and a filtering device (183) for performing a high-frequency emphasis filtering process on the amplitude limit signal, thereby obtaining an equalization-corrected signal.

Abstract: A write control method which varies a write power in response to a recording speed, a recording density, and a type of recording medium, and an optical disc recording apparatus suitable for the write control method. The write control method includes preparing a plurality of standard power values corresponding to recording speeds or recording densities for a plurality of record marks, selecting one of the plurality of standard power values with respect to a record mark to be recorded according to a recording speed or a recording density, and controlling write power of a laser beam according to the selected standard power value. The write control method and apparatus improve recording performance of an optical disc recording apparatus by differently setting write power values according to recording speeds, recording densities, and types of recording media.

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: A method of recording marks onto an optical disc, the optical disc comprising an information layer, by irradiating the information layer by a pulsed radiation beam, a mark (I3 . . . I14) having a time length of nT, n representing an integer larger than one and T representing the length of one period of a reference clock, being recorded by a sequence comprising m write pulses separated by cooling periods, the write pulses within the sequence being allowed to have different time lengths, the write pulses comprised in sequences corresponding to marks of different time lengths being allowed to have different lengths, m being an integer number given by Floor(n/?), where Floor(n/?) defines the largest integer smaller than n/?, wherein a is an integer number larger than or equal to 2. The method characterized by modifying at least the sequence comprising the longest write pulse such that the longest write pulse is replaced by two write pulses.

Abstract: There is disclosed a method of permitting recording setup information required to perform a test recording on an optical disk to be obtained from an external device as the need arises. The method comprises the steps of: measuring an evaluation index associated with recording characteristics with which data was recorded on the optical disk by an optical disk drive; making a decision as to whether the measured evaluation index indicates a state in which recording setup information used in data recording by the optical disk drive should be updated; acquiring recording setup information corresponding to at least the machine ID of the optical disk drive and the medium ID of the optical disk when the evaluation index is judged to indicate the state in which the recording setup information should be updated; and setting the acquired recording setup information in the optical disk drive.

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: 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: The invention discloses an optical recording drive for recording data on an optical carrier such as an optical disk of the DVD or BD format. A radiation source is arranged to emit a write pulse train (80) for writing an optically detectable effect (90) i.e. a pit or mark. Photo detection means (10) detects a first reflected radiation beam pulse (R1) from a start time portion of the write pulse train (80) and generates a corresponding first signal (PS1) indicative of the power in the first pulse, the photo detection means (10) further detects a second reflected radiation pulse (R2) from an end time portion of the write pulse train (80) and generates a corresponding second signal (PS2) indicative of the power in the second pulse. By comparing (e.g.

Abstract: An adaptive writing method of a high-density optical recording apparatus and a circuit thereof. The circuit includes a discriminator for discriminating a magnitude of a present mark of input NRZI data and magnitudes of leading and/or trailing spaces of the input NRZI data, a generator for controlling the waveform of a write pulse in accordance with the magnitude of the present mark of the input NRZI data and the magnitudes of the leading and/or trailing spaces of the input NRZI data to generate an adaptive write pulse, and a driver for driving a light source by converting the adaptive write pulse into a current signal in accordance with driving power levels for respective channels of the adaptive write pulse. The widths of the first and/or last pulses of the write pulse waveform are varied in accordance with the magnitude of the present mark of input NRZI data and the magnitude of the leading and/or trailing spaces, thereby minimizing jitter to enhance system reliability and performance.

Abstract: An exemplary method for optimizing a recording signal of an optical recording apparatus to record data onto a disc, the recording signal having a first pulse-width parameter, the method includes selecting an initial value of the first pulse-width parameter; generating adjusted values based on the initial value to record test data onto the disc respectively; measuring mark lengths of lands; determining average lengths of the mark lengths of lands; determining differences between the average lengths and a predetermined standard length; linear curve fitting the adjusted values and the differences employing the following linear curve fitting equation: Y=AX+B to obtain the constants A and B, wherein X represents the adjusted values, Y represents the differences; determining and storing an optimum value of the first pulse-width parameter to be used for recording the data onto the disc, this optimum value equals to ?B/A. An optical recording apparatus is also provided.

Abstract: A writing current circuit (42) supplies a controlled electrical current to a laser diode (34) for recording data swiftly onto a DVD (16). A plurality of current sources (62) in the writing current circuit (42) supply electrical current directly to the laser diode (34). Each current source (62) respectively receives a single output signal from a current control register (52) included in the writing current circuit (42) which activates or deactivates the current source (62) for supplying a particular quantity of current to the laser diode (34). In one aspect, a pair of current reference signals received by the current source (62) control electrical current supply to the diode (34). Incorporated into these controlling reference signals is a simulation of electrical characteristics of the diode (34). In another aspect, each current source (62) responds to a logical inverse of the output signal from the current control register (52) for controlling overshoot in voltage applied across the diode (34).

Abstract: To provide a new recording method and recording apparatus with respect to an optical recording medium, the recording method and recording apparatus being able to deal with a high density of an optical recording medium of recent years. Recording of a recording track and a prepit is carried out by sequentially deflecting a single beam.

Abstract: In the information recording apparatus, by driving the light source by the pulse signal corresponding to the recording signal, the laser pulse corresponding to the recording signal is irradiated onto the recording medium. The recording signal has the mark period to form the recording mark, and the space period in which the recording mark is not formed. In the mark period, the output level of the laser pulse changes between the normal level and the writing level, thereby, the recording mark is formed on the recording medium. On the one hand, over a predetermined period in the space period, the output level of the laser pulse is changed to the low level lower than the normal level. Thereby, the heat accumulation onto the recording medium, due to the transient response of the laser pulse in the mark period, is reduced, and in the mark period after that, the correct recording mark can be formed.

Abstract: A data recording method according to the present invention is a method for recording data as edge position information, including marks and spaces of multiple different lengths, on a storage medium by irradiating the storage medium with a pulsed energy beam. The method includes the steps of: (A) generating a write code sequence based on the data to be recorded; (B) determining a write pulse waveform, defining the power modulation of the energy beam, according to the code lengths of respective codes included in the write code sequence; and (C) modulating the power of the energy beam based on the write pulse waveform.

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: Methods and devices or writing an optical record carrier, in which a mark representing recorded data is written in a phase-change layer of a record carrier by a sequence of radiation pulses. A rear heating pulse is introduced after a last write pulse and a front heating pulse is introduced before the first write pulse. The power level of the front heating pulse and the power level of the rear heating pulse may be dependent on the length of the mark to be recorded and on properties of the record carrier.

Abstract: A method and apparatus for recording data on an optical disk calculates an optical power at a first recording speed, compares the calculated optical power to a predetermined value, and then determines whether to apply the first recording speed based on a result of the comparison. The optical power at the first recording speed is calculated based on a reference optical power and a measured optical power, and the predetermined value may correspond to the maximum allowable power of a laser pickup. The method and apparatus may be used to control the speeding, timing, and/power of a data recording operation, as well as to compensate for temperature variations and/or power margins of one or more circuits in an optical disk device.

Abstract: In order to ensure recording quality while suppressing the adverse effects due to performance variations among apparatuses and disc radial positions on an optical disc, an optical disc apparatus according to the present invention performs, at the time of data recording, the steps of: acquiring a jitter value and ? value from a reproduced signal based on laser light reflected from the optical disc in relation to a disc radial position; learning a ? value when the acquired jitter value is a minimum as a target ? value; and, if a jitter value acquired thereafter is larger than the minimum jitter value by a preset reference value or above, correcting recording power based on the magnitude relation and the difference between the ? value associated with the acquired jitter value and the target ? value or performing trial record processing.

Abstract: Methods and devices are described for writing to an optical record carrier, in which a mark representing recorded data is written in a phase-change layer of a record carrier by a sequence of radiation pulses. A rear heating pulse is introduced after a last write pulse and a front heating pulse is introduced before the first write pulse. The power level of the front heating pulse and the power level of the rear heating pulse may be dependent on the length of the mark to be recorded and on properties of the record carrier. The method results in a reduced jitter of the marks written, especially when writing at high recording speeds.

Abstract: The present invention provides for an apparatus and method of controlling writing a signal to an optical disc in an optical disk system and including the step of generating a feedback signal to dynamically tune the signal output from a laser source, and including generating a plurality of timing signals serving to define a plurality of sampling windows for selecting data samples from RF signals derived from a signal reflected from the disc, generating a plurality of runlength selection signals to allow for measurement of light reflection at required runlength lands or pits, and measuring light reflected at a runlength land or pit in processing means and employing the measured signal as the said feedback signal for the said tuning of the signal source.

Abstract: In a multilayer optical recording medium having three or more recording layers, when data is recorded on a recording layer far away from an incident surface of laser light, and especially on a recording layer farthest away from the incident surface of the laser light, by applying the laser light, the recording power margin of the farthest recording layer allows for a variation in the optimal recording sensitivity even if the transmittance of the recording layers located between the laser light incident surface side and the target recording layer is varied due to existing recordings and the amount of the laser light passing therethrough is also varied. In this case, the recording layer which is the farthest from an incident surface of laser light has a phase change recording film, and the recording layer which is the nearest from the incident surface of the laser light has a write-once read-multiple recording film.

Abstract: The present invention provides an optical information reproducing method of detecting a record mark formed in an optical information recording medium and generating a reproduced signal, comprising the steps of: detecting a mark length of each record mark on basis of a reproduced signal, and correcting the reproduced signal by a correction amount corresponding to the detected mark length, and an optical information reproducing apparatus for detecting a record mark formed in an optical information recording medium and generating a reproduced signal, comprising: a detection circuit for detecting a mark length of each record mark on basis of a reproduced signal, and a correction circuit for correcting the reproduced signal by a correction amount corresponding to the detected mark length.

Abstract: An optical disk writing apparatus enhances writing accuracy by writing first data (e.g., test data) that encodes a first writing strategy within first patterns on an optical disk, in response to a first writing signal. A reproducing signal is generated in response to reading the first data from the optical disk. Variations between leading and trailing edges of the first writing signal and leading and trailing edges of the reproducing signal are detected. A correction value is determined using a jitter evaluation function to evaluate the detected variations. From these operations, a second writing strategy is determined using the correction value to modify the first writing strategy. Thereafter, second data (e.g., actual data) is written, which encodes the second writing strategy within second patterns on the optical disk.

Abstract: When recording recording information by forming on a recording medium a recording mark whose mark length is an integral multiple of the reference mark length according to a recording signal generated from a recording information signal, this method performs a process of: generating, after recording compensation recording information on the recording medium, a reproduction signal by reading out the compensation recording information; generating from the reproduction signal a reproduction clock whose cycle corresponds to the reference mark length; setting a signal level suitable for binarization determination of the reproduction signal as a distribution reference level, according to the difference in variation between white and black levels of the reproduction signal; and calculating the recording correction value for correcting the compensation recording signal, so that the reproduction signal becomes closer to the distribution reference level around a target cross timing determined based on the reproduction c

Abstract: A recording method, a recording apparatus, and an optical recording medium that can improve quality of a signal reproduced from a high multi-speed recording medium. The recording method includes generating a box type recording pattern including a first pulse, which has a duration determined according to a length of a recording mark and which has a first power level, and a second pulse which has a second power level different from that of the first power level, and recording data according to the box type recording pattern.

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: Provided are a recording/reproducing apparatus and method for optimizing data recording. The recording/reproducing apparatus sets a predetermined length which is an integer multiple of a unit recording length and sets a plurality of recording parameters, with reference to mark/space combinations which can be configured within the predetermined length ahead of a start point of a mark for recording data and mark/space combinations which can be configured within the predetermined length behind an end point of the mark for recording data. Accordingly, by setting a predetermined length and limiting conditions for optimizing recording parameters, and considering run-length combinations which can be configured within the predetermined length, it is possible to quickly and efficiently optimize parameters.

Abstract: An adaptive writing method of a high-density optical recording apparatus and a circuit thereof. The circuit includes a discriminator for discriminating a magnitude of a present mark of input NRZI data and magnitudes of leading and/or trailing spaces of the input NRZI data, a generator for controlling the waveform of a write pulse in accordance with the magnitude of the present mark of the input NRZI data and the magnitudes of the leading and/or trailing spaces of the input NRZI data to generate an adaptive write pulse, and a driver for driving a light source by converting the adaptive write pulse into a current signal in accordance with driving power levels for respective channels of the adaptive write pulse. The widths of the first and/or last pulses of the write pulse waveform are varied in accordance with the magnitude of the present mark of input NRZI data and the magnitude of the leading and/or trailing spaces, thereby minimizing jitter to enhance system reliability and performance.

Abstract: A write strategy method, medium, and apparatus. The method includes writing a signal to a storage medium by using a predetermined power and an initial write strategy, calculating variation characteristics of a data signal which separately correspond to variations of write strategy parameters, if the written signal does not satisfy initial quality standards, and calculating correlations among periods of the data signal and correlations among the write strategy parameters by using the variation characteristics of the data signal, and determining the write strategy parameters based on the correlations among the periods of the data signal and the correlations among the write strategy parameters.

Abstract: An optical recording and reproducing apparatus includes a recording-pulse-shift setting unit that shifts a front edge and a rear edge of a recording pulse and sets a write strategy of the recording pulse, an mark-edge-position evaluating unit that detects a front edge and a rear edge of a mark formed and detects a front mark edge position error and a rear mark edge position error, an assuming unit that assumes that the front mark edge position error is represented by a first linear function and assumes that the rear mark edge position error is represented by a second linear function, a sensitivity calculating unit that executes test recording and calculates sensitivities, and a write-strategy calculating unit that calculates a write strategy of the recording pulse on the basis of the sensitivities.

Abstract: Method and device for generating a stable power control signal in a CD recorder. The power control signal for controlling a laser diode may be a read level, an erase level and a write level. A pickup device outputs a feedback control signal to a read control circuit, and a read power control voltage is thus obtained. Then, the read power control voltage is inputted to a write control circuit, which generates first and second write power control voltages. The read level equals a reference voltage added by the read power control voltage, the erase level equals the read level added by the first write power control voltage, and the write level equals the erase level added by the second write power control voltage, so the read power control voltage and thus the read, erase and write levels are automatically and dynamically adjusted as the feedback control signal varies.

Abstract: An optical recording method for recording mark length-modulated information on a recording medium by using a plurality of recording mark lengths. The optical recording method comprises the steps of: when a time length of one recording mark is denoted nT (T is a reference clock period equal to or less than 25 ns, and n is a natural number equal to or more than 2), (i) dividing the time length of the recording mark nT into ?1T, ?1T, ?1T, ?2T, ?2T, . . . , ?iT, ?iT, . . .