Abstract: The invention relates to a predetermined synchronization pattern (40), a so-called VFO field, in, for example, the headers 3 of an information carrier. The proposed predetermined synchronization pattern (40) consists of sequences of 3T marks and spaces (41), of 8T marks and spaces (42) and of 5T marks and spaces (43). This sequence of patterns is advantageous for setting the dynamic range of an Automatic Gain Controlled (AGC) amplifier located within a device reading the information carrier.

Abstract: When a code word sequence is generated by converting input data words of p bits into code words of q bits and concatenating adjacent ones of the code words with a merge bit sequence of r bits in order to obtain the best DSV value, according to one aspect, the adjacent code words are concatenated with the merge bit sequence of r bits which is selected, free from the restriction of the minimum run-length of (d+1)T and the maximum run-length of (k+1)T based on the run-length limiting rule RLL(d, k) but permitting the minimum run-length of (d+1)T and the maximum run-length of (k+2)T.

Abstract: A record carrier, and method for manufacturing such record carrier, which can be copies with the aid of a copying apparatus, while the copied record carrier is unreadable. During copying with the aid of the copying apparatus, merge bits are selected such that consecutive channel bits or a first type, the type “1”, are separated by at least Ia and at most Ib consecutive and continuous bits of the second type, the type “0”, and vice versa. The original record carrier, at least over a number of neighboring blocks of channel bits, is provided with specific blocks of merge bits, while consecutive channel bits of one type are separated by Ic or Id consecutive bits of the other type, with Ic<Ia and Id<Ib.

Abstract: A method for producing polycarbonate based on 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexanone and 4,4-(metaphenylene diisopropyl) diphenol is disclosed. The method is characterized in that the recovery and/or further processing of the polycarbonate is performed at temperatures below 290° C. The polycarbonate thus produced has high purity and high transmission and is suitable for the manufacture of optical data stores.

Abstract: The present invention is relative with a method for recording further data on a recording medium on which there re pre-recorded data obtained on modulating M-bit data to N-bit data, where M<N. The further recorded data are recorded by changing a certain bit or bits of the N-bit data, with the remaining portion of the bits of the N-bit data being fixed.

Abstract: A method of recording information in which each recording mark is formed in a recording medium, by irradiating a pulse chain of an energy beam including a first pulse, a middle pulse chain, a last pulse and a negative pulse following the last pulse. The adjusting average power of the first middle, last and negative pulses to designated power levels of the first, middle, last and negative pulses recorded in a control data zone.

Abstract: A recording method includes the steps of generating recording data in such a manner that, when m-bit data is converted into a data symbol of n bits (m<n), and connection bits such that the summed value of DC components per unit time decreases are selected from among a plurality of connection bits and are added after the m-bit data symbol, the connection bits differing from connection bits which are added when the n-bit data symbol is a data symbol other than the special data symbol are added to generate recording data; and recording the generated recording data on a recording medium.

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 optical disc recording apparatus can draw an image by radially vibrating a laser beam under stable focus control. A pickup radiates the laser beam onto the optical disc rotated by a spindle motor. A focus servo controller maintains a constant spot diameter of the laser beam on the optical disc by detecting a return light of the laser beam reflected back from the optical disc. An irradiation position controller operates when the pickup opposes a label face of the optical disc for controlling an irradiation trajectory of the laser beam to vibrate in a radial direction of the optical disc while the laser beam runs along circumferential zones defined on a coloring layer of the label face. A modulating section modulates an intensity of the laser beam for forming dots along the circumferential zones so as to draw the image.

Abstract: A method of recording data on an optical recording medium includes forming a mark or a space using a recording waveform which includes a DC record pattern, and an erase pattern that includes a multi pulse. According to the method and an apparatus using the method, the distortion of a mark can be prevented and the shape of a mark can be improved, thereby increasing recording/reproducing characteristics.

Abstract: A recording apparatus for recording modulated data on a rewritable recording medium includes a data modulation section for modulating data in accordance with a prescribed modulation rule; a parameter value changing section for changing at least one parameter value of the prescribed modulation rule; and a recording section for recording the data modulated in accordance with the prescribed modulation rule on the recording medium.

Abstract: The present invention relates to a recording and reproducing method and apparatus for an optical disk of the phase transition type that can be overwritten. According to this invention, the capacity of repeated rewriting of the optical disk is expanded by recording either non-inverted write data or inverted write data at random. The deterioration due to the repeated rewriting at a start point and an end point of the recording is suppressed by recording a synchronizing signal 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 to stop recording.

Abstract: In an information recording medium including a plurality of sector fields and having various pieces of information recorded in the sector fields, the header field in each sector field includes a first field in which a continuously repeated pattern complying with the run length limitation in the predetermined range is recorded, a second field in which an address mark including a violation pattern different from a reproduced pattern obtained by reproducing the repeated pattern when a defective pit which cannot be recognized as a pit is included in pits representing the repeated pattern is recorded, the violation pattern exceeding the run length limitation in the predetermined range, and a third field in which address data is recorded.

Abstract: An optical storage medium can be provided by which illegal usage of the optical storage medium involving an infringement on the copyright can be prevented effectively without impairment of the functions for reproducing physical format information and optical storage medium manufacturing information. The optical storage medium includes a main information region in which encrypted data information is recorded as a pit row that is capable of being read out by means of light and a control data region. In the control data region, key information for decoding the encryption of the data information, the physical format information and the optical storage medium manufacturing information are recorded by wobbling a groove.

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: In an information recording medium including a plurality of sector fields and having various pieces of information recorded in the sector fields, the header field in each sector field includes a first field in which a continuously repeated pattern complying with the run length limitation in the predetermined range is recorded, a second field in which an address mark including a violation pattern different from a reproduced pattern obtained by reproducing the repeated pattern when a defective pit which cannot be recognized as a pit is included in pits representing the repeated pattern is recorded, the violation pattern exceeding the run length limitation in the predetermined range, and a third field in which address data is recorded.

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 recording medium in which information is to be recorded is permitted to get into a first state by a first power level of an energy beam and permitted to get into a second state by a second power level higher than the first power level of the energy beam. The information is recorded on the recording medium by moving the energy beam and the recording medium relatively to each other and irradiating the recording medium with the energy beam so that the first and second states are formed with predetermined lengths and at predetermined intervals on the recording medium. Four power levels (first, second, third and fourth power levels) are used as the power level of the energy beam. The information is recorded while the second power level is increased to x times and the first, third and fourth power levels are increased to y times. The information recorded as described above is reproduced, and reproductive jitter is observed.

Abstract: A device according to the invention for writing information to an information carrier (1) includes conversion means (7) for converting symbols in an information signal (SINFO) into pulse sequences in a control signal (STR). The device further includes a transducer (10) for generating a physically detectable pattern on the information carrier (1) in response to the control signal (STR). The conversion means (7) include assignment means (702) for assigning properties of the pulse sequences to symbols in the information signal (SINFO). These properties include the duration and the magnitude of pulses in the pulse sequence. The conversion means (7) further include at least one counter (711) for supplying a count signal (TC1) after a time interval, which counter is coupled to the assignment means (702). The conversion means (7) further include a controllable delay line (761) coupled to the at least one counter (711), for delaying the count signal (TC1), and to the assignment means (702).

Abstract: A data recording controller for speedily modulating input data and generating modulated data. The controller includes a modulation circuit for modulating input data and generating modulation candidates. A selection circuit is connected to the modulation circuit to receive the modulation candidates from the modulation circuit and select one of the modulation candidates as the modulated data based on a conversion parameter. A plurality of memories simultaneously store the modulation candidates, respectively. An output circuit receives the modulation candidates read from the memories and outputs the modulated data, which the selection circuit selects from the modulation candidates.

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: The present invention provides a data recording device that can restrain the low-pass component in data to be written onto a recording medium without causing a problem in decoding the data using likelihood information. This data recording device includes: a data bit string combining unit that combines, by predetermined combining rules, a plurality of predetermined parity bit strings one by one with a data bit string obtained prior to a change to the bit order in a bit order rearranging procedure, thereby generating a plurality of composite data bit strings; and a data bit string selecting unit that selects one encoded data bit string from a plurality of encoded data bit strings generated through encoding procedures including the bit order rearranging procedure carried out for each of the plurality of composite data bit strings. Based on the selected encoded data bit string, the data recording device performs a data write operation onto the recording medium.

Abstract: An information recording medium includes a data recording area for recording data; a first drive information area for recording first drive information: and a second drive information area for recording second drive information. The first drive information and the second drive information each include a plurality of recording and reproduction conditions, and the plurality of recording and reproduction conditions each define an operation condition of an information recording and reproduction apparatus, which can have the information recording medium mounted thereon, for recording and reproducing the data. The plurality of recording and reproduction conditions are arranged in the order of time at which the plurality of recording and reproduction conditions are recorded.

Abstract: A method of generating an efficient sequence of “nm+m−1” level random numbers, each sub-sequence of “m” successive random numbers thereof having a different pattern, including the steps of generating a sequence of n-level random numbers based on an initial value, a number being generated at a time, determining whether a pattern of a sub-sequence is “used”, if the pattern of the sub-sequence is “used”, setting a different value to the initial value, if the pattern of the sub-sequence is not “used”, accepting the newly generated number and marking the pattern as “used”. All of the steps are repeated until all of “nm” patterns are exhausted. Since the newly generated number is rejected if the pattern of the sub-sequence is “used”, the sequence becomes the shortest one of which all of “nm” patterns are exhausted.

Abstract: The present invention relates to a modulated signal generator capable of carrying out signal processing at a higher speed or capable of supporting a special format and a new format with ease. A modulation processing storing unit 130 has a modulation processing program required for producing an optical disc master 320 stored therein in advance. Information data recorded in an master optical disc 310 is reproduced by an information reproducing unit 110 and is outputted to a modulation controller 120. The modulation controller 120 carries out the signal modulation processing onto the reproduced information data in accordance with the signal modulation processing program so as to generate a data stream and stores the data stream in a modulated information storing unit 140 as necessary.

Abstract: In an information recording medium including a plurality of sector fields and having various pieces of information recorded in the sector fields, the header field in each sector field includes a first field in which a continuously repeated pattern complying with the run length limitation in the predetermined range is recorded, a second field in which an address mark including a violation pattern different from a reproduced pattern obtained by reproducing the repeated pattern when a defective pit which cannot be recognized as a pit is included in pits representing the repeated pattern is recorded, the violation pattern exceeding the run length limitation in the predetermined range, and a third field in which address data is recorded.

Abstract: A method of recording data on a compact disc is provided includes modulating the data of 1 byte to p-channel bits, recording the modulated data when a minimum mark length is greater than 0.5 &mgr;m and smaller than 1.0 &mgr;m, p/q is greater than 4.5 and smaller than 8 when the minimum mark length corresponds to q-channel bits, and a format efficiency is greater than 0.6 and smaller than 1.0. Thus, data can be recorded on an existing compact disc at a higher density.

Abstract: The present invention relates to an optical disk device and can be applied to, for example, a reproduction system of a phase-change-type optical disk device handling high density recording in order to improve the detection accuracy of specific patterns, such as a synchronizing pattern, without increasing the redundancy of the format. A specific pattern is detected by using NRZI data D1R that is obtained by signal processing of a reproduction signal DRF, and has been NRAI-modulated from pulse-position-modulated data D2R.

Abstract: The present invention relates to a recording and reproducing method and apparatus for an optical disk of the phase transition type that can be overwritten. According to this invention, the capacity of repeated rewriting of the optical disk is expanded by recording either non-inverted write data or inverted write data at random. The deterioration due to the repeated rewriting at a start point and an end point of the recording is suppressed by recording a synchronizing signal 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 to stop recording.

Abstract: A recording method and a recording apparatus whereby digital data is recorded onto a disc as run-length limited code used for modulating marks or spaces on the disc and, at the same time, the recorded digital data is encrypted by using key data which is also recorded onto the same disc by varying the shape of marks or spaces with timing having no effect on the edges of the marks or the spaces. A playback method and a playback apparatus reproduces the digital data and the key data recorded on the disc by the recording method and/or the recording apparatus from the disc with the key data used for decrypting the reproduced digital data.

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: Disclosed are a method for recording wobble signals on an optical disc and an optical disc on which the wobble signals are recorded. After pre-coding bit data of address information to be recorded on an optical disc on the basis of at least 4 wobble units, wobble data pre-coded on at least 4 wobble units is modulated by a BPSK (Binary Phase Shift Keying) or ASK (Amplitude Shift Keying) method, and the modulated wobble data is alternately recorded on both sides of a land and/or groove of the optical disc. The case where wobble signals, recorded on sides of signal tracks of a groove and a land, in anti-phase are consecutively repeated is avoided. Further, the case where wobble signals, recorded on sides of signal tracks of a groove and a land, having different amplitudes are consecutively repeated is avoided.

Abstract: A method of and apparatus for recording data on an optical recording medium form a mark or a space by using a recording waveform having an erase pattern containing a multi-pulse. The method and the apparatus prevent distortion of the mark or the space and improve a mark shape such that a recording/reproducing characteristic of the optical recording medium is improved.

Abstract: Signal quality evaluation is performed using a predetermined reproduction signal, a first pattern corresponding to a signal waveform pattern of the reproduction signal, and a given pattern corresponding to the signal waveform pattern of the reproduction signal and being different from the first pattern.

Abstract: When a record decision unit 22 judges that recording has been interrupted, the recording data in a predetermined frame is ended. Data are continuously recorded onto a disk until the frame synchronous signal duration following the predetermined frame. Thereafter, the control output generated from the head output controller 14 is controlled to interrupt the recording operation. When the record decision unit 22 judges the resuming of recording, the control output from the head output controller 14 is controlled to resume the recording operation onto the disk from the frame synchronous signal duration in which the recording of data onto the disk has been interrupted.

Abstract: A plurality of types of recording pulse control rules for which the recording pulse waveform is determined according to the information signals to be recorded are stored in advance in an optical disk. When recording to the optical disk, information is recorded using a recording pulse where, due to the focused laser beam, the temperature in the recording layer cools more rapidly at a second information recording layer closer to the side where light is incident than at a first information recording layer farther away from the side where light is incident.

Abstract: Information is recorded on and reproduced from a disk ECC-block by ECC-block. Every ECC block is composed of plural sectors. A recording command is generated which contains information of a recording position on the disk. The information of the recording position is stored into a nonvolatile memory. Data is recorded on the disk in response to the recording command. In cases where power supply is turned on after interruption of power supply terminates, a specified ECC block is detected from the information stored in the nonvolatile memory. The specified ECC block is adversely affected by the interruption of power supply during the recording of data on the disk. One of a reproducing command and a verify command is generated for at least one sector of the specified ECC block. Data is reproduced from the specified ECC block on the disk in response to the one of the reproducing command and the verify command.

Abstract: According to the present invention, in an optical disk apparatus constructed to supply signals for controlling a semiconductor laser drive circuit provided to an optical pickup from a signal processing circuit through a flexible cable, the semiconductor laser drive circuit is so constructed as to generate a drive current signal for the semiconductor laser on the basis of a binary signal and a clock signal which are supplied from the signal processing circuit through the flexible cable and the signal processing circuit is so constructed as to supply the clock signal during recording of data and stop the supply of the block signal during reproduction of data.

Abstract: In an information recording medium, positions of pits are modulated in a direction intersecting a direction of reading of pits, so that a predetermined information is recorded. In this information recording medium, the whole of the predetermined information or a part of the predetermined information is randomized through the used of spread spectrum.

Abstract: A digital sum variation (DSV) computation method and system is proposed, which is capable of determining the DSV value of a bit stream of channel-bit symbols to thereby find the optimal merge-bit symbol for insertion between each succeeding pair of the channel-bit symbols. This DSV computation method and system is characterized in the use of a Zero Digital Sum Variation (ZDSV) principle to determine the DSV. This DSV computation method and system can find the optimal merge-bit symbol for insertion between each succeeding pair of the channel-bit symbols in a more cost-effective manner with the need for a reduced amount of memory and utilizes a lookup table requiring a reduced amount of memory space for storage so that memory space can be reduced as compared to the prior art. This DSV computation method and system is therefore more advantageous to use than the prior art.

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: An optical disc of a sampled servo format allows a simplifed configuration of an apparatus recording a master disc for optical discs. A method for recording on the optical disc and an optical information recording and/or reproducing apparatus are also disclosed. Onto the optical disc according to the sampled servo method where a synchronization pit and a tracking pit are formed on the same track, data marks that carry information data is recorded between two tracks that are adjacent to each other. Furthermore, when the information data are recorded on and reproduced from such an optical disc, firstly a difference value between read values that are read from the respective tracking pits formed on two tracks adjacent to each other is obtained as a tracking error signal.

Abstract: An information storage medium according to an embodiment of this invention has an area for storing predetermined data modulated according to the (d, k; m, n) modulation rule. The predetermined data includes at least one SYNC code in a predetermined recording unit, and the number of “1”s included in a predetermined number of a series of channel bits at an arbitrary position in the SYNC code is not more than a half the predetermined number.

Abstract: The object of the present invention is to provide a data recording method and optic recording medium that is capable of reproducing address data accurately by reducing the correlation of address data between adjacent tracks, reducing the effect of cross-talk between adjacent tracks on the recording clock and by making it possible to apply a cross-talk canceller to the wobble signal. The data-recording method of recording data while controlling the correlation between a first data string and a second data string that are contained in recording data, and is provided with a selecting process of selecting inversion/no inversion of first data string such that the correlation between first data string and second data string is reduced; and a recording process of recording first data string according to selected inversion/no inversion polarity, and recording control code that indicates whether inversion/no inversion was selected for first data string.

Abstract: The irradiation time and/or the irradiation power of a laser beam is varied to perform multi-level recording on a recording layer in five stages or more. On the recording layer 12 of an optical recording medium 10, defined contiguously are virtual recording cells 40 within a groove 16 along tracks arranged at track pitches of 1 to 1.5 &mgr;m. The time and/or the irradiation irradiation power of the laser beam is modulated in five stages or more corresponding to the information to be recorded on each of the virtual recording cells 40 in order to form recording marks 48A-48G having five stages or more of different sizes and/or optical transmittance. The overall optical reflectivity of each of the virtual recording cells 40 is modulated in multi-stages to vary in five stages or more the entire reflectivity level of the reading laser beam used upon reading in the virtual recording cell including the outside of the recording mark.

Abstract: A code modulation and demodulation method includes removing a DC component of a code stream to be modulated when source data is recorded on an optical information storage medium and controlling a suppression of the DC component contained in the code stream when the source data is converted into a codeword to be recorded on an optical information storage medium. The method includes determining a control timing to suppress the DC component of the code stream to which the source data are converted, performing a code conversion at each control time for the DC component so that the code stream branches into a pair of branch code streams one of which extends in a direction where a running digital sum (RDS) of the code stream increases, and another one of which extends in the direction where the RDS of the code stream decreases, and selecting the path of the code stream that has a most bounded path around RDS ‘0’ from the paths of the branch code streams each control time.

Abstract: A recording and reproducing system is broken down into a recording unit for producing a digital audio data signal from MIDI music data words asynchronously produced at irregular intervals and a playback unit for reproducing the MIDI music data codes from the digital audio data signal, wherein synchronous data nibbles are supplemented in the irregular intervals among the MIDI music data words for producing a data stream, and the digital audio data signal is produced from the data stream through a differential phase shift keying and a phase code modulation so as to record the MIDI messages in a digital versatile disk at high dense.

Abstract: In an information recording medium including a plurality of sector fields and having various pieces of information recorded in the sector fields, the header field in each sector field includes a first field in which a continuously repeated pattern complying with the run length limitation in the predetermined range is recorded, a second field in which an address mark including a violation pattern different from a reproduced pattern obtained by reproducing the repeated pattern when a defective pit which cannot be recognized as a pit is included in pits representing the repeated pattern is recorded, the violation pattern exceeding the run length limitation in the predetermined range, and a third field in which address data is recorded.

Abstract: In an information recording medium including a plurality of sector fields and having various pieces of information recorded in the sector fields, the header field in each sector field includes a first field in which a continuously repeated pattern complying with the run length limitation in the predetermined range is recorded, a second field in which an address mark including a violation pattern different from a reproduced pattern obtained by reproducing the repeated pattern when a defective pit which cannot be recognized as a pit is included in pits representing the repeated pattern is recorded, the violation pattern exceeding the run length limitation in the predetermined range, and a third field in which address data is recorded.

Abstract: A digital modulation apparatus and method used for a DVD-RAM and a DVD-R/RW and for increasing the margin of an operation of an external device is provided. The digital modulation apparatus includes a 4-stage pipeline and includes a mode selection unit, a field enabling signal generation unit, a data fetch and sync code generating unit, an eight-to-fourteen modulation plus (EFMplus) conversion unit, and a non-return-to-zero inverted (NRZI) conversion unit. The mode selection unit generates a mode selection signal for selecting one from a DVD-RAM operation mode and a DVD-R/RW operation mode in response to a control signal. The field enabling signal generation unit selectively generates recording field enabling signals related to a DVD-RAM, or selectively generates recording field enabling signals related to a DVD-R/RW, in response to a start signal and the mode selection signal and provides the recording field enabling signals to the data fetch and sync code generation unit.