Abstract: In an apparatus and method for checking a network synchronization clock signal in a communication system, the apparatus generates a divided clock signal which is the same as an externally inputted network synchronization clock signal, compares the value of one period of the network synchronization clock signal to the value of one period of the divided clock signal, and determines whether the network synchronization clock signal is normal or not. Thus, the reliability of an operation of checking the network synchronization clock signal is enhanced.

Abstract: The present invention relates to a method of calibrating a radial offset of an optical recorder after a recordable record carrier is inserted (1000), the method comprising the steps of: determining wobble signal amplitudes at different radial offset values of a radial control loop (102), finding an optimal radial offset value at which the wobble signal amplitude is substantially maximal (104), and recording the data on at least one wobbled recording track (T1, T2, T3, . . . Tn) of the recordable record carrier using the optimal radial offset value (106). This is useful for all optical recording devices.

Abstract: A recording medium, such as a high-density and/or read-only recording medium, such as BD-ROM, which contains a control ionformation, such as copy protection information, encoded in intermittent or alternate wobbled pits, and to methods and apparatuses for forming, recording, and reproducing data on the recording medium.

Abstract: A wobble signal for an optical storage device is generated by adjusting a center frequency (?0) of a band pass filter based on an expected frequency of the wobble signal and/or an estimated position of a pick-up apparatus and filtering an input signal corresponding to the wobble signal from the pick-up apparatus with the adjusted band pass filter to provide the wobble signal. Adjusting the center frequency (?0) of the band pass filter may also be based on a measured phase change of the band pass filter. Systems for generating a wobble signal, wobble signal detection circuits and optical storage devices are also provided.

Abstract: A focus servo method includes: causing light to enter an objective lens at an eccentric position; irradiating light onto recording marks of an optical recording medium in an oblique direction with respect to a thickness direction of the optical recording medium; detecting light reflected by the recording marks as a reflection of the light irradiated onto the recording marks; and controlling a position of the objective lens based on the detected light.

Abstract: An optical disc medium comprises a track groove, along which main information is recorded. The track groove is divided into a plurality of blocks. The plurality of blocks each include a plurality of frames. The plurality of frames each include one shape of wobbles indicating sub information, among a plurality of prescribed shapes of wobbles. The plurality of blocks each have address information. The address information is represented by a string of at least one piece of sub information represented by the shape of wobbles of at least one of the plurality of frames.

Abstract: An optical disc medium comprises a track groove, along which main information is recorded. The track groove is divided into a plurality of blocks. The plurality of blocks each include a plurality of frames. The plurality of frames each include one shape of wobbles indicating sub information, among a plurality of prescribed shapes of wobbles. The plurality of blocks each have address information. The address information is represented by a string of at least one piece of sub information represented by the shape of wobbles of at least one of the plurality of frames.

Abstract: An optical pickup includes a lens frame, and the lens frame includes protruding portions provided with through-holes, coil connecting portions protruding away from a supporting-wire holding portion at corners. The coil connecting portions are provided with cutout portions constituted by two surfaces intersecting each other at the both side surfaces of the coil connecting portions in order to form waist portions at a wound portion. Supporting wires are overlapped with the lead wires wound around the waist portions of the coil connecting portions when viewed from above and connected to these wound lead wires with solder. With this configuration, it is possible to provide an optical pickup which enables connecting the terminated portions of the wound coil lead wires and the supporting wires with a reduced amount of solder, thereby reducing the weight and the cost.

Abstract: An optical disc medium comprises a track groove, along which main information is recorded. The track groove is divided into a plurality of blocks. The plurality of blocks each include a plurality of frames. The plurality of frames each include one shape of wobbles indicating sub information, among a plurality of prescribed shapes of wobbles. The plurality of blocks each have address information. The address information is represented by a string of at least one piece of sub information represented by the shape of wobbles of at least one of the plurality of frames.

Abstract: A recording medium includes a substrate having a microscopic pattern, which includes a shape of continuous substance of approximately parallel grooves formed with a convex shaped section and a concave shaped section alternating on a surface of the substrate. A recording layer is formed on the microscopic pattern and a light transmitting layer has a thickness of 0.05 mm to 0.12 mm formed on the recording layer. The microscopic pattern satisfies a relation of P??/NA, wherein P is a pitch of the convex shaped section, ? is a wavelength of a reproducing light beam and NA is a numerical aperture of an objective lens. The microscopic pattern also includes modulated address information formed on both side walls of the convex shaped section viewed from the light transmitting layer as a wobble, both the side walls being parallel to each other, and furthermore wherein the address information is modulated by the phase-shift keying modulation system.

Abstract: This invention improves the accuracy of wobble signal detection for disc discrimination and reduces discrimination errors due to noise. In an optical disc apparatus, a wobble signal generator creates a wobble signal from an electrical signal which has been obtained from conversion by a pickup. A bandpass filter (BPF) is set to change its central frequency to a wobble frequency f0 and to fn different from the wobble frequency, and the filter extracts the respective frequency components from the wobble signal. An amplitude-measuring section measures amplitude levels A0 and An of the extracted multiple signals. A disc discriminator compares the multiple amplitude levels and if the amplitude A0 is greater than the amplitude An by at least a threshold level Ath, judges that a wobble is present.

Abstract: An optical disk (D) is provided with multiple grooves (G) and multiple lands (L) alternating with each other. The address data recording regions have a pair of wobbling sections (31a, 31b) formed on both sidewalls of a groove (G) and having an identical phase. Thus, it is possible to obtain push-pull signals having a larger amplitude, which is advantageous for increasing the data recording density.

Abstract: A recording medium, such as a high-density and/or read-only recording medium, such as BD-ROM, which includes copy protection information for preventing illegal copying of the contents recorded on the recording medium, and to methods and apparatuses for forming, recording, and reproducing data on the recording medium.

Abstract: According to one embodiment, when a focus servo goes off and the distance between an objective lens and a recording layer of an optical disc does not coincide with a focal length of the objective lens, a control voltage or current corresponding to an optical disc wobble stored in a memory is superimposed on a control voltage or current supplied to a driving mechanism to move an objective lens along an optical axis for re-focusing, and the superimposed voltage or current is supplied to the driving mechanism. Therefore, pull-in of a focus servo for re-focusing is possible in a short time.

Abstract: A wobble signal extraction circuit includes: an RF signal component acquiring portion for acquiring an RF signal component from at least one of first and second signals received by two light receiving portions, the two light receiving portions being obtained through division in halves with a direction along which each track of an optical recording medium extends as a boundary; a wobble signal acquiring portion for acquiring a wobble signal by subtracting the second signal from the first signal; an RF signal component binarizing portion for binarizing the RF signal component; a wobble signal binarizing portion for binarizing the wobble signal; and an exclusive OR arithmetically operating portion for arithmetically operating an exclusive OR of the binarized RF signal component and the binarized wobble signal; wherein balances between amplitudes of the first and second signals are detected based on an arithmetic operation result obtained in the exclusive OR arithmetically operating portion.

Abstract: An optical disc has a wobble pregroove which continues in a circumferential direction of the optical disc and wobbles in a radial direction of the optical disc such that the wobble pregroove meanders around a mean center line of meandering. Information recording process is performed by the steps of irradiating an optical beam along the wobble pregroove to form pits, thereby recording information in the form of the pits, and controlling the recording of the information in accordance with a radial distance of the wobble pregroove relative to the mean center line of meandering. Information reproducing process is performed by the steps of irradiating an optical beam along the wobble pregroove to optically detect pits which are formed along the wobble pregroove, thereby reproducing information in the form of the detected pits, and controlling the reproducing of the information in accordance with a radial distance of the wobble pregroove relative to the mean center line of meandering.

Abstract: An information recording method recording information on an information recording medium in the form of a recording mark having a time-length nT by irradiating optical beam pulses thereto according to a recording strategy, the recording strategy comprises the steps of forming the recording mark on the recording medium by controlling a power of the optical beam pulses to one of ternary values Pw, Pb and Pe (Pw>Pe>Pb) and irradiating a heating pulse having a power set to Pw, and a cooling pulse having a power set to Pb, upon the information recording medium alternately; and forming a space on the recording medium subsequent to the recording mark by irradiating the optical beam pulse with the power Pe, the recording strategy increasing the number of said heating pulses by one each time the time-length of the recording mark is increased by 2T, the recording strategy setting a heat pulse starting time sTtop and a heat pulse termination time eTtop for a first heating pulse, when forming a recording mark of a

Abstract: A mark S/H circuit (66) samples, for example, a signal A generated as a photodetector (20) detects a return beam from marks of an optical disk (10), a space S/H circuit (68) samples a signal A generated through detection of a return beam from spaces, and amplifiers (70 and 72) justify amplitudes of the sampled A signals from the marks and spaces. A mark/space selector switch (74) selects alternately and combines the mark and space signals whose amplitudes have been justified. After A, B, C, and D signals A1 to D1 are subjected individually to a series of processes up to the combination process, a wobble processing circuit (80) adds them in predetermined combinations, finds differences among the added signals after justifying the amplitudes of the added signals, and thereby reproduces a wobble signal (107).

Abstract: A TE signal polarity determining method, includes: (a) obtaining a wobble related signal, an RF related signal, a TE signal and an accessing direction; and (b) determining if an original polarity of a TE signal should be changed or not according to phases of the RF related signal, the wobble related signal and/or the accessing direction.

Abstract: Disclosed is a TE signal polarity determining method, which includes: (a) obtaining a detection signal from an optical disc; (b) obtaining characteristics of the detection signal corresponding to different polarities of the TE signal; and (c) determining whether an original polarity of the TE signal should be changed or not according to the obtained characteristics.

Abstract: An apparatus and a method for generating an ATIP data are provided. The apparatus, based on a wobble signal generated by reading a re-writable compact disc, generates an ATIP data; the apparatus includes: a frequency demodulator for demodulating the wobble signal to generate an original ATIP data signal; an ATIP clock generating circuit for generating an ATIP clock signal based on the wobble signal; and a data generating circuit, coupled to the frequency demodulator and the ATIP clock generating circuit, for generating the ATIP data based on the number of the original ATIP data signal at a first logic level during one period of the ATIP clock signal. This apparatus uses the number of the original ATIP data signal at a first logic level during one period of the ATIP clock signal and the bi-phase rule to precisely generate the ATIP data.

Abstract: An apparatus for reading subdivided information from an optical disk, which comprises a track groove and on which information is recorded along the track groove is disclosed. The apparatus includes an optical head, which irradiates the optical disk with light and generates an electric signal responsive to part of the light that has been reflected from the optical disk, read signal processing means for generating a wobble signal which has an amplitude changing with the wobble pattern from the electric signal, rise value acquiring means for sampling and holding an absolute gradient value of the wobble signal when the signal rises, fall value acquiring means for sampling and holding an absolute gradient value of the wobble signal when the signal falls, and subdivided information detecting means for determining the subdivided information by majority by comparing the values held by the rise and fall value acquiring means with each other.

Abstract: An objective lens is included in an optical pickup device that records and/or reproduces an information signal onto and/or from an optical recording medium. The objective lens has a numerical aperture of 0.82 or higher, has first and second surfaces that are both aspherical, and focuses a light beam onto the optical recording medium. The first and second surfaces have surface-to-surface eccentricity therebetween that causes an aberration, the aberration being correctable by tilting an optical axis of the objective lens relative to a central axis of the light beam incident on the objective lens. The aberration caused by the surface-to-surface eccentricity includes a third-order coma aberration. When the optical axis is tilted relative to the central axis of the incident light beam so that the third-order coma aberration becomes substantially 0 m? rms, each of astigmatism, spherical aberration, and high-order coma aberration becomes 20 m? rms or less.

Abstract: The present invention provides a first light source (21) that emits light of a first wavelength, that at least either records onto or reproduces information from an information recording medium (30), a light source (22) that emits light of a second wavelength that records onto or reproduces information from an information recording medium (33), a light source (23) that emits light of a third wavelength that records onto or reproduces information from an information recording medium (23), focusing means, an optical element (28) that passes light of the first wavelength and diffracts light of the second and third wavelengths, wherein the optical element (28) is an optical element in which grooves are formed in a substrate, wherein the expression: 380 nm?(n?1)×d?420 nm is satisfied, where n is a refractive index of the substrate at a wavelength of 400 nm, and d (nm) is a depth per step of the grooves, and wherein the grooves are formed in two steps of depth d and depth 2d.

Abstract: In a method of and an apparatus for creating a reproduced wobble signal by subtracting an estimated crosstalk signal, expressed by a sine waveform having a frequency approximately equal to the meandering frequency of grooves, from an original wobble signal and recording or reproducing an information pattern at a predetermined position of an optical disc, a carrier signal, which is caused to correspond to the meandering of the groove by being subjected to phase synchronization, is assumed based on the reproduced wobble signal, a crosstalk remaining component is estimated from the amplitude and phase of the region, which meanders in approximately the same phase as the estimated carrier signal in the reproduced wobble signal, and from the amplitude and phase of the region which meanders according to a signal different from the estimated carrier signal, and the estimated crosstalk is updated to cancel the remaining component.

Abstract: A recording medium includes a substrate having a microscopic pattern, which includes a shape of continuous substance of approximately parallel grooves formed with a convex shaped section and a concave shaped section alternating on a surface of the substrate. A recording layer is formed on the microscopic pattern and a light transmitting layer has a thickness of 0.05 mm to 0.12 mm formed on the recording layer. The microscopic pattern satisfies a relation of P??/NA, wherein P is a pitch of the convex shaped section, ? is a wavelength of a reproducing light beam and NA is a numerical aperture of an objective lens. The microscopic pattern also includes modulated address information formed on both side walls of the convex shaped section viewed from the light transmitting layer as a wobble, both the side walls being parallel to each other, and furthermore wherein the address information is modulated by the phase-shift keying modulation system.

Abstract: Pseudo synchronization due to crosstalk is detected with a small circuit scale in decoding address information from an MSK-modulated wobble signal. An MSK mark detection unit detects MSK marks periodically placed as synchronization signals in a wobble signal. A first synchronization state determination unit determines synchronization establishment with a detection position of each MSK mark as a reference, or out-of-synchronization. A prediction timing generation unit periodically generates a timing at which each MSK mark is to be detected based on the synchronization position after the establishment of synchronization.

Abstract: A method for generating a wobble clock signal. When the wobble signal becomes deformed or a defect on the optical disc is found, the present invention provides a stable wobble clock signal, which is used to maintain a stable rotation speed when the optical disc is processed. In addition, the present invention also determines whether the wobble signal is deformed according to the result of comparing the width of the wobble signal at different status with the average of the half cycle width of the wobble signal.

Abstract: Wobble detection for detecting data in a wobble signal modulated with a base signal includes sampling the wobble signal at a substantial maximum and a substantial minimum of a base signal within a wobble period, producing a value of the wobble signal at the substantial maximum of the base signal with an unchanged sign and a value of the wobble signal at the substantial minimum of the base signal with a reversed sign, determining a sum of the values within the wobble period, and decoding the sum to detect data.

Abstract: An apparatus for scanning a track on a record carrier has a head for scanning the track and generating a read signal. The tilt between the head and the record carrier (11) is compensated via a tilt servo loop. Thereto the head is provided with tilt compensating actuators (42). A measure of the tilt is jitter in the read signal generated by a front end (43) and filter (44). A wobble generator (40) provides a wobble signal to the actuators and to an input of multiplier (45) for synchronous detection of the jitter. The output of the multiplier (45) is coupled to a low pass filter (46) for generating a tilt error signal coupled to a tilt controller (47) for generating a tilt control signal.

Abstract: An information recording medium 1 at least comprises a substrate 13 having a microscopic pattern 20, which is constituted by a shape of continuous substance of approximately parallel grooves formed with a groove section G and a land section L alternately, a recording layer 12 formed on the microscopic pattern 20 and a light transmission layer 11 formed on the recording layer. The microscopic pattern 20 is formed so as to satisfy a relation of P<?<NA and a thickness of the light transmission layer 11 is within a range of 0.07 to 0.12 mm, wherein P is a pitch of the groove section G or the land section L, ? is a wavelength of reproducing light beam and NA is a numerical aperture of an objective lens. Further, there provided an information recording medium, which is improved in cross erase and recorded in high density, and a reproducing apparatus and a recording apparatus for the information recording medium.

Abstract: An information recording medium 1 at least comprises a substrate 13 having a microscopic pattern 20, which is constituted by a shape of continuous substance of approximately parallel grooves formed with a groove section G and a land section L alternately, a recording layer 12 formed on the microscopic pattern 20 and a light transmission layer 11 formed on the recording layer. The microscopic pattern 20 is formed so as to satisfy a relation of P<?<NA and a thickness of the light transmission layer 11 is within a range of 0.07 to 0.12 mm, wherein P is a pitch of the groove section G or the land section L, ? is a wavelength of reproducing light beam and NA is a numerical aperture of an objective lens. Further, there provided an information recording medium, which is improved in cross erase and recorded in high density, and a reproducing apparatus and a recording apparatus for the information recording medium.

Abstract: An information recording system for recording information on an optical disc using a reference clock signal generated based on a push-pull signal including a wobble frequency component, the system includes an amplitude obtaining unit for obtaining an amplitude value of the push-pull signal, a threshold calculation unit for calculating a displacement threshold of the push-pull signal based on the amplitude value obtained by the amplitude obtaining unit, and a noise reduction unit for generating a corrected push-pull signal by correcting the push-pull signal such that a displacement exceeding the displacement threshold is reduced. The reference clock signal is generated based on the corrected push-pull signal generated by the noise reduction unit.

Abstract: The invention provides an optical disk that enables high-speed reproduction of address signals. A wobble address system for optical disk supports various types of synchronization, such as phase synchronization, bit synchronization, word synchronization, etc., to be established easily with high detection reliability with the use of an self-orthogonal code. Thus, the invention provides a method for easily synchronizing an address signal, i.e., high-speed reproduction of the address signal. Further, by virtue of an efficient modulation system of the address signal and redundancy thereof, it becomes possible to detect address information with high reliability. This capability is particularly effective in optical recording/reproduction with a blue light source whose signal light quantity and reproduction quality are prone to reduce.

Abstract: In a particular type of high-density optical recording systems, a solid immersion lens (SIL) is used in the objective system to focus a radiation beam onto an information layer of an optical record carrier. The distance between the exit surface of the SIL and the entrance surface of the record carrier is typically 25 nm to allow evanescent coupling of the radiation from the SIL to the optical record carrier for a system using a blue laser as radiation source. Such a system is also called a near-field system, deriving its name from the near field formed by the evanescent wave at the exit face of the SIL. A suitable gap signal, representing the width of the gap, is used to control the width of the gap during operation of the system. Tolerances in the optical elements and opto-mechanical components of the optical system of the optical recording system can lead to an offset in the position of the focus point of the objective system.

Abstract: Described herewith is an optical disk manufacturing apparatus for reading recorded digital data from an optical disk, comprising an encryption unit (22, 23) for encrypting entered digital data according to a plurality of key information; an optical disk substrate manufacturing unit 2 for manufacturing an optical disk substrate 4 on which the encrypted digital data and key information are recorded in the form of physical form changes; a reflection film forming unit 41 for forming a reflection film on the optical disk substrate 4; and a key information recording unit 7 for recording key information on the optical disk substrate on which the reflection film is formed. The reflection factor of the optical disk is changed locally, thereby giving a jitter to the position information of each pit edge, and desired data is recorded additionally according to this jitter. Pits, etc.

Abstract: An information recording medium 1 at least comprises a substrate 13 having a microscopic pattern 20, which is constituted by a shape of continuous substance of approximately parallel grooves formed with a groove section G and a land section L alternately, a recording layer 12 formed on the microscopic pattern 20 and a light transmission layer 11 formed on the recording layer. The microscopic pattern 20 is formed so as to satisfy a relation of P<?<NA and a thickness of the light transmission layer 11 is within a range of 0.07 to 0.12 mm, wherein P is a pitch of the groove section G or the land section L, ? is a wavelength of reproducing light beam and NA is a numerical aperture of an objective lens. Further, there provided an information recording medium, which is improved in cross erase and recorded in high density, and a reproducing apparatus and a recording apparatus for the information recording medium.

Abstract: An optical disc apparatus includes a reproduction unit that reproduces a wobble signal on an optical disc, the wobble signal having physical address information subjected to phase modulation by using a code sequence that has a predetermined cycle and that is subjected to code modulation in accordance with a modulation rule common to the cycles; a phase detection unit that performs phase detection to the reproduced wobble signal to demodulate the code sequence; an evaluation value calculating unit that sequentially calculates an evaluation value indicating how much the code sequence coincides with the modulation rule in units of codes in the code sequence; an integrator that cyclically integrates the evaluation value in the cycle; and a synchronous detection unit that detects the presence of the code sequence and a reference position of the code sequence from the integrated evaluation value.

Abstract: A groove is formed on a master disc. The groove is formed substantially along a spiral standard locus, but a groove position is displaced in a direction crossing the standard locus according to record data. The wobble is determined from a wobble signal. A wobble is formed such that an average value of displacement of the groove position with the standard locus as a reference is zero for each predetermined data unit.

Abstract: An apparatus of phase-frequency detector for adjusting wobble clock signal and wobble signal in the same phase, comprising: a first logic gate, receiving a first protection signal and a second protection signal and outputting a third protection signal according to a logic operation; a first flip-flop, coupled to the first logic gate, outputting the third protection signal as a first output signal when the wobble clock trigger; a second flip-flop, coupled to the first logic gate, outputting the third protection signal as a second output signal when the wobble signal trigger; a second logic gate, coupled to the first and the second flip-flop, outputting a fourth protection signal according to a logic operation; a third logic gate, coupled to the second logic gate, receiving the third and the fourth protection signal, and outputting a fifth protection signal according to a logic operation; and a control signal generator, receiving the wobble clock, the input signal, and the fifth protection signal and determinin

Abstract: A method for restoring focusing of a laser beam on a track of an optical disc for reading or writing data from/to the track when the focusing of said beam onto said track has been lost, wherein two categories, A and B, of focus lost causes are defined, A being due to an external shock and B due to other reasons and wherein a focus re-capture is performed with the use of focus control information stored in a memory only for a category B focus lost.

Abstract: An optical recording medium allowing high-density recording, where a groove having a shallow U-shaped cross section wider than certain width, a master for manufacturing optical recording medium, a manufacturing apparatus thereof, and a manufacturing method thereof are provided. A exposure beam (61) and a exposure beam (62) are recombined together with a first exposure beam (60) in a second PBS (47) so that traveling directions thereof may be the same direction. At this time, the exposure beam (61) and the exposure beam (62) are arranged so that both optical axes may be aligned at certain distance. Thereby, a width of a spot formed by combining these beams can be extended, and light exposure of the spot can be proper to form a shallow groove, as typically showed in FIG. 3.

Abstract: The invention relates to an optical drive for e.g. CD, DVD, HD-DVD or BD disks. A radial servomechanism controls the radial position of a laser beam in response to a push pull signal (PP). The radial servomechanism has an amplifier (VGA, 55) with a variable gain (G). The drive contains wobble signal detection means (51, 52, 53) so as to provide an amplitude (WA) of the wobble signal from the push pull signal (PP). Transition detection means (54) assesses if the focused radiation beam is or has been exposed to a change in a local optical environment on the optical carrier, such a read-write transition. In case of a transition, the radial servo gain (G) is adjusted in dependence of a ratio (r) of a wobble amplitude (WA_b) just before said transition to a wobble amplitude (WA_a) just after said transition so as to obtain a substantially constant radial bandwidth of the radial servomechanism.

Abstract: A wobble demodulator for reproducing digital information from an optical recording medium in which a track is formed in accordance with a wobble signal that is MSK-modulated so as to contain the digital information by a carrier signal with a predetermined frequency and a sine wave signal with a frequency different from that of the carrier signal, includes: a wobble signal detector for detecting a wobble signal of the track from the optical recording medium; a wobble PLL for detecting the carrier signal based on the wobble signal detected by the wobble signal detector; a multiplier for multiplying the carrier signal detected by the wobble PLL by the wobble signal detected by the wobble signal detector and outputting a multiplied output; a MSK detector for detecting a MSK modulation mark having a phase or a frequency different from that of the carrier signal, based on an integrated value obtained by integrating the multiplied output from the multiplier on a predetermined section basis; and a MSK synchronization

Abstract: A demodulation circuit accurately demodulates a wobble signal of an optical disk without being affected by a phase shift induced by crosstalk. An A-D converter subjects wobble signal reproduced from an optical disk to A-D conversion and feeds a result of conversion to a zero-crossing detection circuit. The zero-crossing detection circuit detects zero-crossing points of the wobble signal. A sinusoidal wave generation circuit generates a sinusoidal wave by means of sequentially connecting sinusoidal wave elements whose periods are each equal to a time interval between zero-crossing points. A multiplier multiplies an original wobble signal by a sinusoidal wave signal. A slicer detects an HMW-modulated portion of the wobble signal, and another slicer detects an MSK-modulated portion of the wobble signal.

Abstract: An optical recording medium has a user data area and a lead-out area, wherein the user data area and the lead-out area each has grooves and lands formed thereon. Wobbles are formed on at least one lateral surface of grooves of the user data area and the lead-out area, and configured such that wobble characteristics are made different between the user data area and the lead-out area. Different types of wobbles are formed on the grooves of either the user data area or the lead-out area, thereby preventing an optical pickup that performs recording/reproduction from deviating from the user data area. Also, in a multi-layer optical recording medium, a whole area of a recording layer is configured to have a same condition, thereby preventing deterioration in reproduction and/or recording due to a difference in light power transmittance of another recording layer.

Abstract: An apparatus for reproducing a wobble signal, including: a first filter unit receiving a wobble signal obtained by reading a wobble from a disc and passing a first band including a monotone frequency set according to the type or speed of the disc so as to generate a first wobble output signal; a second filter unit, when the wobble signal includes at least one frequency component, receiving the wobble signal and passing a second band including a multi-frequency set according to the speed of the disc so as to generate a second wobble output signal; and a wobble clock signal generation unit generating a wobble clock signal by quantizing one of the first and second wobble output signals. Accordingly, the wobble signal can be detected according to the type of disc, the speed of a disc, or a driving mode for the disc.

Abstract: A method for recording address information on an optical recording medium, and the optical recording medium are discussed. According to an embodiment, there is provided an optical recording medium including a wobble-shaped recording track that is formed thereon based on a wobble signal, the wobble signal being modulated by a predetermined modulation method, wherein a physical address information is included in the wobble modulation, data bit “0” and “1” comprising the physical address information being comprised of a 2n+4 (n?0)-wobble basis and being distinguished from each other such that each data bit has at least three same values and at least one different value in the modulated wobble signal with respect to the 2n+4 (n?0)-wobble basis.

Abstract: The present invention relates to a device (1) for scanning an optical recording medium (3), comprising an optical unit (5) for reading data from and/or writing data to said recording medium (3) by scanning said recording medium (3) with a radiation beam (21), said radiation beam (21) being positioned on said recording medium (3) in response to a tracking error signal, a tracking means (7) for generating said tracking error signal and a position control means (11) for controlling a radial scanning position of said radiation beam (21) in respect to a track on said recording medium (3).

Abstract: An optical disc is manufactured under a uniform condition by forming grooves and lands on the entire surface of the disc. The optical disc is configured to obtain a reliable reproduction signal, and the grooves and lands are formed on a lead-in area, a user data area and a lead-out area of the optical disc. Since the same manufacturing condition can be adopted in mastering discs, the yield can be enhanced and the manufacturing cost can be reduced.