Abstract: An optical read/write drive such as a DVD+RW drive writes a block of new data to a read/write medium by locating an edit bit in the block of data that has already been written to the medium, and writing the block of new data to the medium, beginning or ending at the edit bit. The edit bit may be chosen to avoid errors arising from polarity conflicts between data already written to the disc and the new data. The edit bit could be, for example, a differing transition bit in a sync codeword of a modulation-encoded block.

Abstract: A signal recording/playback apparatus includes a recording data converter. The recording data converter converts on a data pattern having a large influence on adjacent tracks on an optical disk, and outputs the converted data to an optical pickup. Specifically, by performing a data converting process in which, for a data pattern having a predetermined length of at least consecutive bits having identical values, part of the bits is inverted based on a conversion table, the recording data converter compensates a recording operation. Alternatively, instead of inverting the bits, by controlling the output power and pulse width of a laser, the recording operation is compensated. The signal recording/playback apparatus includes a played-back data converter. In the data playback mode of the signal recording/playback apparatus, the data converted by the recording data converter is identified and decoded into the original data by the played-back data converter. The played-back data converter outputs the original data.

Abstract: A coding table portion includes six coding tables each storing a code word and status information indicating a coding table for use in modulating a next input data word in order to obtain a next code word which satisfies a predetermined run length restriction rule even if the next code word is coupled directly with the preceding code word, corresponding to each input data word. In the coding table portion, the code words and status informations allocated corresponding to input data words of a number set up preliminarily in succession from the highest appearance frequency to a lower one in one or more coding tables of the plural coding tables are replaced with code words having smaller RDSs and status informations allocated corresponding to other input data words in the same coding table. Consequently, the input data word is modulated using the six coding tables.

Abstract: An information recording method for recording information on a rewritable recording medium include recording synchronizing signal information in a synchronizing signal portion on the rewritable recording medium, and recording data information in a data portion of the writable recording medium after the synchronizing signal portion by forming a record mark in the data portion. The data information corresponds to both ends of each record mark. Each time the synchronizing signal information is recorded, a length of the synchronizing signal portion changes and a start position of the synchronizing signal portion changes, and each time the data information is recorded, the record mark and space between the record mark are substantially inverted.

Abstract: A recording and reproducing method and apparatus for an optical disk of the phase transition type is provided. This method comprises the steps of deciding at random to invert or not to invert write data that has a predetermined block length; inverting the write data if the decision is to invert the write data; and recording either the non-inverted write data or the inverted write data into the photo-sensitive record layer. A synchronizing signal is recorded before the write data and/or dummy data after the write data in the way such that thermal stress is less likely to occur. A record end position can be determined precisely by detecting a stop pulse.

Abstract: An optical data storage system, particularly suited for use in the information and entertainment industries. A near-field crystal optical memory (NCOM) system includes an electron trapping media, particularly an &agr;-Al2O3:C crystal or Cu+-doped fused quartz, that is sensitive to light. Information is stored and retrieved using blue and green laser light, respectively. High data density is achieved using a near-field scanning optical microscopy (NSOM) technique, by placing the optical probe in a very close proximity to the crystal surface. The storage system enables ultra-high data densities reaching 2500 Gb/in2.

Abstract: The present invention relates to method and apparatus for suppressing a DC component of coded sequence with no additional bit for suppressing a DC component, and for decoding the coded sequence. The present modulating method modulates a source data twice based on a first mapping table and a second mapping table wherein the first mapping table contains coded data corresponding to the source data and the second mapping table contains at least one coded data, capable of suppressing low frequency components, to which at least one source data among all source data contained in the first mapping table is mapped, selects one of the modulated data based on at least one among the conditions of the value of a previous source data, whether low-frequency suppression has been conducted or not, the value of subsequent modulated data, and whether or not RLL constraints are violated, and records the selected one onto an optical recording medium.

Abstract: The life of a rewritable information carrier such a CD-E covered by a phase-change recording layer is extended by varying the manner of representing information of an information block, for subsequent recordings, in the same portion of the record carrier. The manner can be changed, for example, by shifting the initial position at which representing information is written along the track over a distance randomly selected within predefined boundaries; or by writing a varying amount of information representing information from the end of the block before the start of information from the beginning of the information block to rotate the information in the track; or by scrambling the information in a varying manner such as using different keys. The manner of representation can be changed, for example, for each subsequent recording on the same portion of the record carrier. This causes different patterns to be recorded in the same portion, even if the same information is recorded in that portion of the track.

Abstract: An optical information recording device forms a mark, in which the mark indicating record information is formed by irradiating a record light pulse on a record medium, by controlling a strength of the record light pulse according to both of a mark length of the mark and a record density in a mark length direction of the record medium.

Abstract: An optical read/write drive such as a DVD+RW drive writes a block of new data to a read/write medium by locating an edit bit in the block of data that has already been written to the medium, and writing the block of new data to the medium, beginning or ending at the edit bit. The edit bit may be chosen to avoid errors arising from polarity conflicts between data already written to the disc and the new data. The edit bit could be, for example, a differing transition bit in a sync codeword of a modulation-encoded block.

Abstract: Apparatus and method for recording data to an optical disc to prevent unauthorized duplication of the disc. The disc includes a data placement zone to which first data are written at a first data rate as the disc is rotated at a selected linear velocity. The disc further includes a velocity disruption zone to which second data are written at a second different data rate as the disc is rotated at the selected linear velocity. The variation in frequency between the first and second data rates preferably causes a readback system to lose frequency lock on the second data during a continuous access operation on the first and second data. An unauthorized disc can also be detected by comparing the disc linear velocity as the second data are accessed to a target linear velocity. Access to the disc can be denied when a velocity mismatch is detected.

Abstract: There is disclosed a recording method for performing a DSV control while recording a recording signal generated by inserting a synchronous signal for decoding reproduction data into every predetermined number of code words in a code word string satisfying a predetermined run length restriction rule and to be outputted into a recording medium, when a plurality of coding tables are used to convert an input data word of p-bits to a code word of q-bits (q>p), and the code word string obtained by directly coupling the code words is recorded and reproduced in a recording medium such as an optical disk and magnetic disk, or transmitted via a transmitting portion, wherein the p-bits are 8 bits, the q-bits are 15 bits, and the predetermined run length restriction rule stipulates that a minimum run length of the signal obtained by NRZI-converting the code word excluding the synchronous signal is 3T, and a maximum run length is any one of 11T, 12T, 13T, and 14T.

Abstract: There is disclosed a synchronous signal generating method, recording apparatus, transmitting apparatus, recording medium and transmission medium in which a plurality of coding tables is used to convert an input data word of p-bits to a code word of q-bits (q>p), and a code word string obtained by directly coupling the code words is recorded and reproduced in a recording medium such as an optical disk and magnetic disk, or transmitted via a transmitting portion. A synchronous frame consists of a synchronous signal and the cord word string satisfying restriction on minimum run length and maximum run length.

Abstract: A method of and an apparatus for modulating data to be resistant to channel distortion. A space extending encoder performs a first code transformation to extend a run length of digitized data to a predetermined length and outputs the space-extended data. A multiplexer multiplexes the space-extended data and data transformed by a predetermined second code transformation. A format converter converts the multiplexed data into a predetermined format which is suitable for writing to a recording medium. The apparatus and method enable recorded data to be resistant to channel distortion, enable the data to be recorded with increased recording density, and enable the data written to the recording medium to be reproduced with improved reliability.

Abstract: A recording medium having a dummy signal area on at least one side of a recording area is used and information is recorded with a dummy signal added to at least one of the leading and trailing sides in the recorded information signal. The user data area remains unaffected by repeated overwriting so that recorded user data is reproduced correctly. In particular, the wave form distortion caused by fluidization of a recording film remains at the dummy signal area and does not affect the user data area, so that the reproduction of the target information (user data) is assured.

Abstract: This invention resolves the limitations of the binary data encoding and storage system by encoding multi-valued meaning to data elements prior to the recording and storing of these multi-valued data elements based on a plurality of quantities in a memory point. In order to make a single memory point suitable to record multi-valued data elements, where each value has a special meaning in a particular recording, quantities of magnetism or light, like its intensity, shape, etc., are digitized or analogized so that each of the quantities can be recorded and extracted. The invention additionally includes systems and methods for using multi-valued data elements, including wireless transmission.

Abstract: An encoder converts a binary data word to a binary code word. The encoded bits have first and second binary values at a predetermined clock interval. A pulse generator responds to the encoded bits to generate energizing pulses during each clock interval in which the encoded bits have the first binary value. The energizing pules have a uniform duration less than the clock interval. A laser responds to the energizing pulses for recording on a medium.

Abstract: A method of recording a digital signal representing digital data onto a recording medium by changing a position of each edge of each of a plurality of pits in accordance with the digital signal is provided.

Abstract: A method and apparatus for recording or reproducing data in which high performance encoding and a high efficiency decoding are realized to lower the decoding error rate. A magnetic recording and/or reproducing apparatus 50 includes, in a recording system, a modulation encoder 52 for modulation encoding input data in a predetermined fashion and an interleaver 53 for interleaving data supplied from the modulation encoder 52 to re-array the data sequence.

Abstract: A recording device according to the present invention has a function (202, 206, 207) of dividing precoded record data into data blocks of a prescribed length to adjust to a magneto-optical disk (3) and adding an intrinsic pattern before and after the data blocks. As the intrinsic pattern, a pattern which reduces a decoding error of maximum likelihood decoding at an end of each data block is used. Therefore, even when data is inserted after preceding, code correlation of a precoded signal can be maintained at a location where division is performed.

Abstract: In a run-length limited encoding method used in an optical data storage system for encoding input data of two bits into corresponding output data of five bits, a minimum run-length of zeroes (0's) in a stream of the output data is 3; a maximum run-length of zeroes (0's) in the stream of the output data is 11; and the number of 1 included in binary numbers of five bits expressing the corresponding output data is 1 or 0. In the encoding method, the input data of two bits is one of “00”, “01”, “10” and “11”; and the corresponding output data is one of “10000”, “01000”, “00100” and “00010”.

Abstract: An encoder converts a binary data word to a binary code word. The encoded bits have first and second binary values at a predetermined clock interval. A pulse generator responds to the encoded bits to generate energizing pulses during each clock interval in which the encoded bits have the first binary value. The energizing pules have a uniform duration less than the clock interval. A laser responds to the energizing pulses for recording on a medium.

Abstract: The invention relates to a method for generating a primary binary signal having a predetermined spectral shape in a predetermined frequency range, in particular having a notch in the power spectrum in a predetermined frequency range. In order to avoid crosstalk between a primary binary signal and a secondary binary signal it is proposed according to the invention that data-words are modulated into channel-words forming the channel bitstream of the primary binary signal and that the modulation of the data-words is chosen such that the predetermined spectral shape of the channel bitstream of the primary binary signal is achieved by using an evaluation criterion based on a spectral weight function the shape of which is tailored to the spectral extent of the channel bitstream of a secondary binary signal.

Abstract: A method for encoding and recording non-audio data on a compact disc medium. The non-audio data is encoded as a non-audio data track having an audio format compatible with a standard format which calls for digital audio encoding utilizing a predefined number of bits per sample. The non-audio data is encoded using less than the predefined number of bits per sample, and preferably no more than one-half the predefined number of bits per sample. The non-audio data is preferably encoded such that the audio signal resulting from the non-audio data track is substantially equally distributed across an audible spectrum and is an approximation of white noise. The non-audio data track, once encoded, is recorded along with a plurality of audio tracks on the compact disc. Additional non-audio data may be encoded as a watermark within the non-audio data track. A compact disc recorded thusly is compatible with existing CD players.

Abstract: An apparatus and method are disclosed for optimizing the writing of data to an optical disc to improve readback characteristics and minimize the effects of errors. An optimization circuit generates an optimized modulation signal which is used to modulate a writing beam of a laser beam recorder, the optimized modulation signal comprising a series of data symbols that correspond to resulting pits and lands on the optical disc. The optimization circuit optimizes the locations of pit and land transitions on the optical disc by individually adjusting leading and trailing edges of the data symbols, as well as amplitudes of the data symbols. In this manner, the particular length of each pit and land on the disc can be individually selected based on nominal symbol length, as well as other factors including radial and angular locations of the pits and lands on the disc.

Abstract: Digital signal sequences to be recorded in predetermined unitary recording areas are transformed into blocks, a plurality of bit data carrying all digit levels to be read and determined upon reproduction are included in the resultant blocks, and sequences of the data blocks are recorded in the recording medium in the unitary recording areas. Upon reproduction, the blocks of the read signals obtained from a recording medium are recognized, a threshold value is determined for each block on the basis of the values of read signals corresponding to bit data carrying all digit levels to be read and determined, and each digit level of bit data in the read signal are read and determined on the basis of the threshold values.

Abstract: A magnetic recording and/or reproducing apparatus which achieves high performance encoding and high efficiency decoding to lower the decoding error rate. A magnetic recording and/or reproducing apparatus 50 includes, in its recording system, an error correction coder 51 for error correction coding input data and an interleaver 52 for scrambling the sequence of data supplied from the error correction coder 51.

Abstract: A signal can be detected based on a level slice system and detection delay time can be reduced by setting the recording density of a header field in a linear direction lower (coarse) than that of a user data recording field. Further, a signal can be detected based on the level slice system and detection delay time can be reduced by using a mark position form having a large detection margin as an information recording system of the header field. A readout error of a sector number due to a detection error is compensated for by recording address marks AM for attaining byte synchronization of the header field in both of a head portion and tail portion of information recorded in the header field.

Abstract: Some of various multisignal (a plurality of signals except zero in the conventional binary system ) which are a variety of memories employed as signals instead of a single memory in the binary system are recorded in a medium for multisignal, by moving a recorder for multisignal to a determined position. An extractor is moved to a determined position to extract a part of the multisignal which have been recorded at that position in advance. When any change has to be made to the recorded multisignal, the change is made by the recorder. The multisignal can be used in two or more pairs as well. When processing a signal in the multisignal method in which various signals are used instead of 1 in the conventional binary system, the medium erases, writes, and corrects the signal with a machine which uses multisignal of light, magnetism, etc. that can be clearly discriminated from one another.

Abstract: A data recording medium suitable for an optical disk such as DVD is disclosed. The data recording medium has a plurality of sectors. The sector comprises a header area to store address information of the sector, a gap area for power calibration of a laser beam used for data recording, a data recording area to store a plurality of modulated codes obtained by modulating the data, a postamble area located immediately after the data recording area, and a buffer area to separate sectors. The modulated code includes information to demodulate a modulated code located immediately before the each modulated code. The postamble area stores information to demodulate the final demodulated code in the data recording area. Data pattern stored in the postamble area includes synchronization pattern, is determined based on DSV of the data pattern, or satisfies the run length limitation.

Abstract: An optical disc in which hidden data are stored for forensic tracking or copy protection purposes. This disc includes a contiguous user data portion comprising a set of user data samples which, when accessed by a readback system, generates a human detectable output. The disc further includes a null zone adjacent the contiguous user data portion comprising a sequence of user data fields storing a set of user data samples which, when accessed by a readback system, generates an output with a specified signal to noise ratio so as to be substantially undetectable by a human, wherein hidden data are written to at least selected ones of the user data fields of the null zone to convey a specified informational message related to the optical disc, the specified informational message undetectable by a human when the null zone is accessed by the readback system.

Abstract: The present invention is aimed at providing an optical disk, an optical disk device, and an optical disk reproduction method, for allowing for stable and efficient reading of address information. The optical disk includes a plurality of tracks each divided into a plurality of recording sectors. Each of the recording sectors includes a header region. The header region includes address information for identifying the position of the corresponding recording sector and address synchronous information for identifying the recording position of the address information for bit synchronization. The address information has been modulated using a run length limit code of a maximum inversion interval of Tmax bits (Tmax is a natural number), and the address synchronous information includes two patterns of which inversion interval is (Tmax+3) bits or more, so that the reproduced signal of the address synchronous information is distinguished from the reproduced signal of other information.

Abstract: A jack is provided to be inserted with a cable dedicated to analog transmission, a cable dedicated to digital transmission, and a cable dedicated to analog and digital transmissions. A recording device is also provided to have the jack and a cable identifying unit so that the signal to be recorded is automatically switched according to the transmitted digital signal and the cable identified result given by the cable identifying unit.

Abstract: An information recording apparatus for injecting an energy beam into a recording medium to form locally a region different in physical properties from a non-recording region to thereby record information, has a drive for driving an energy generation source for changing the number of injected energy pulses in a mark forming period in accordance with the mark length so that the interval between arbitrary two points of the change of injected power level at the time of information recording is substantially set to be longer than a half of a detection window width in order to make it easy to drive a recording energy generation source to thereby form said mark accurately and speedily and, at the same time, in order to secure a sufficient time required for cooling the recording medium.

Abstract: Thermal stress is prevented from accumulating on a disk recording medium. Data to be recorded is divided into 32-kilobyte clusters, and a front link area and a back link area, whose lengths are randomly changed, formed of a total of 8 frames are added before and after the clusters. Then, the data is recorded on a predetermined area of a disk on the basis of address data prerecorded on the disk.