JP2003257128A - Information recorder and modulation circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an information recorder and a data modulation circuit with which satisfactory data can be obtained during reproduction. <P>SOLUTION: When exclusive OR transformation is performed by adding initial data Tj at the head of block data, the DSV (digital sum variation) value, the variation component of a DC signal, the maximum value of a 0/1-run length, and the maximum value of a 1T-run length of the recorded signal on a medium are measured with a DSV measuring circuit 3, a peak value measuring circuit 4, a 0/1-run length measuring circuit 5, and a 1T-run length measuring circuit 6, and the initial data Tj such that all of these become minimums are selected by a selection circuit 7 on the basis of these measured results. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording device for recording digital information on a recording medium and a modulation circuit for modulating digital information.

[0002]

2. Description of the Related Art Regarding an information recording apparatus for recording digital information on a recording medium and a modulation circuit for modulating the digital information, the applicant previously filed Japanese Patent Application No. 10-518167 (Japanese Patent Application Laid-Open No. 10-816929). I am applying.

In the data modulation according to the prior application, as shown in FIG. 7, N-bit initial data Tj is added to the head of one block of data, and the initial data Tj and the head N-bit data D0 of the basic data are added. And an exclusive OR between the calculation result D'0 and the next N-bit data D1 of the basic data. Thereafter, in the same manner, the exclusive OR calculation is repeated up to the last N bits of one block, so that Tj is added to the beginning 1
Calculate the transformed data for the block. Such converted data is calculated by changing Tj and only the type of Tj, that is, 2 N powers.

In the invention of the above-mentioned prior application, the N of 2
DSV (Digital Sum Variant)
ation) and the peak value of DC fluctuation (when each converted data is actually recorded in the medium) are calculated, and Tj having the smallest peak value and DSV is selected as the initial data. In this selection, the peak values of the DC fluctuations are first compared for the converted data of the Nth power of 2, and Tj having the smallest peak value is selected as the initial data. Then, in such selection, if there are a plurality of Tj's having the smallest peak values, then the converted data having the plurality of Tj's as initial data is converted into the DSV.
And Tj having the smallest DSV is selected as initial data.

According to the invention of the above-mentioned prior application, both the peak value of the DC fluctuation and the DSV can be suppressed, so that data can be efficiently recorded on the medium. Further, by taking the exclusive OR as described above, it is possible to suppress the error propagation in the data series at the time of reproduction. Since the details of the configuration that brings about these effects are described in the specification of the above-mentioned prior application, the description thereof is omitted here.

[0006]

However, according to the invention of the prior application, modulated data in which 0 or 1 continues for a long period of time may be selected when recording on a medium, which results in There is a problem that the DC component becomes redundant. Even if the modulated data with suppressed DSV is selected, if there are many 1T patterns on the medium or if they are repeated for a long time, the Viterbi decoding during reproduction is adversely affected, and as a result, reproduction is performed. There was a problem that an error was triggered.

Therefore, an object of the present invention is to provide an information recording apparatus and a data modulation circuit which eliminate such disadvantages and can obtain good data during reproduction.

[0008]

According to the present invention, in addition to the peak value of the DC fluctuation and the DSV, the run length of 0 or 1 and the number of repetitions of 1T when recording data on the medium are noted. The data conversion is performed by selecting an initial value that is suppressed.

According to a first aspect of the present invention, in an information recording apparatus that modulates block data and then records the modulated data on a medium, the modulating means that performs the modulation has at least 2 bits or more for the block data. After adding the initial data, the additional conversion means for performing a predetermined data conversion by the initial data and the block data, and the peak value of the DC fluctuation when the converted data generated by the additional conversion means is recorded on the medium. A peak value measuring means for measuring, a DSV value measuring means for measuring a DSV value when the converted data is recorded on the medium, and a run length of 0 or 1 when the converted data is recorded on the medium. 0/1 run length measuring means for measuring the maximum value, and a plurality of types of conversions generated by the additional conversion means for a plurality of types of the initial data The peak value, the DSV value, and the 0/1 run length value measured on the data are compared with each other, and the selection means selects the initial data that suppresses these values together as the initial data. To do.

According to a second aspect of the present invention, in the first aspect, the selecting means gives priority to the converted data of the plurality of types in the order in which the peak value and the DSV value are suppressed, and the priority is high. 0 of the converted data in order from the one
The / 1 run length value is compared with the set value, and the initial data of the converted data whose 0/1 run length value first falls below the set value is selected.

According to the invention of claim 3, in claim 2, 0
When there is no converted data whose run length value is lower than the set value for the first time, the initial value of the converted data having the highest priority is selected.

According to a fourth aspect of the present invention, in an information recording apparatus for modulating block data and then recording the same on a medium, the modulating means for modulating the block data has at least 2 bits or more. After adding the initial data, the additional conversion means for performing a predetermined data conversion by the initial data and the block data, and the peak value of the DC fluctuation when the converted data generated by the additional conversion means is recorded on the medium. Peak value measuring means for measuring, DSV value measuring means for measuring DSV value when recording the converted data on the medium, and maximum value of 1T repetition times when recording the converted data on the medium 1T run-length measuring means for measuring, and a plurality of types of converted data generated by the additional converting means for a plurality of types of the initial data The peak value measured with, D
It is characterized by further comprising: selecting means for comparing the SV value and the 1T run length value, respectively, and selecting as initial data initial data such that these values are both suppressed.

According to a fifth aspect of the present invention, in the fourth aspect, the selecting means gives priority to the plurality of types of converted data in the order in which the peak value and the DSV value are suppressed, and the priority is high. 1 of the converted data in order from the one
The T run length value and the set value are compared, and the initial data of the converted data in which the 1T run length value first falls below the set value is selected.

According to the invention of claim 6, in claim 5, 1
If there is no post-conversion data whose T run-length value first falls below the set value, the initial value of the post-conversion data with the highest priority is selected.

According to a seventh aspect of the present invention, in an information recording apparatus for modulating block data and then recording the same on a medium, the modulating means for performing the modulation has at least 2 bits or more for the block data. After adding the initial data, the additional conversion means for performing a predetermined data conversion by the initial data and the block data, and the peak value of the DC fluctuation when the converted data generated by the additional conversion means is recorded on the medium. A peak value measuring means for measuring, a DSV value measuring means for measuring a DSV value when the converted data is recorded on the medium, and a run length of 0 or 1 when the converted data is recorded on the medium. 0/1 run length measuring means for measuring the maximum value, and 1T for measuring the maximum value of the number of repetitions of 1T when recording the converted data on the medium. And a peak value, a DSV value, a 0/1 run length value, and a 1T run length value measured with respect to a plurality of types of converted data generated by the additional conversion means with respect to a plurality of types of the initial data, respectively. And a selecting means for comparing and selecting initial data as the initial data such that these values are suppressed together.

According to an eighth aspect of the present invention, in the seventh aspect, the selecting means gives priority to the converted data of the plurality of types in the order in which the peak value and the DSV value are suppressed, and the priority is high. 0 of the converted data in order from the one
After the conversion of the / 1 run length value and the set value and the comparison of the 1T run length value and the set value, both of the 0/1 run length value and the 1T run length value are first below the respective set values after conversion. Select the initial data of the data,
It is characterized by

According to a ninth aspect of the present invention, in the eighth aspect, when there is no converted data in which both the 0/1 run length value and the 1T run length value are first lower than the respective set values, there is no priority. It is characterized in that the initial value of the converted data having the highest rank is selected.

The invention of claim 10 is the same as that of claim 8
If there is no post-conversion data in which both the 0/1 run length value and the 1T run length value first fall below the respective set values, the 0/1 run length value and 1T
It is characterized in that either one of the run length values is first selected to be the initial value of the converted data which is lower than the set value.

According to a fourteenth aspect of the present invention, additional conversion means for adding at least 2 bits or more of initial data to the block data and then performing predetermined data conversion by the initial data and the block data, and the additional conversion means generate the additional data. Peak value measuring means for measuring the peak value of the DC fluctuation when recording the converted data on the medium, and DSV value measuring means for measuring the DSV value when recording the converted data on the medium, 0/1 run length measuring means for measuring the maximum value of the run length of 0 or 1 when recording the converted data on the medium, and a plurality of the plurality of types generated by the additional converting means for the plurality of types of the initial data. The peak value, DS measured on the converted data of the type
A modulation circuit comprising: a selection unit that compares V value and 0/1 run length value and selects initial data as the initial data such that these values are suppressed together.

According to a fifteenth aspect of the present invention, in the fourteenth aspect, the selecting means gives a higher priority to the plurality of types of converted data in the order in which the peak value and the DSV value are suppressed, and the higher priority is given. The 0/1 run length value and the set value of the converted data are compared in order from
It is characterized in that the initial data of the converted data whose run length value is first lower than the set value is selected.

According to a sixteenth aspect of the present invention, in the fifteenth aspect, when there is no converted data whose 0/1 run length value is lower than the set value for the first time, the initial value of the converted data having the highest priority is given. Is selected.

According to a seventeenth aspect of the present invention, additional data is added to the block data by at least 2 bits, and then the predetermined data is converted by the initial data and the block data. Peak value measuring means for measuring the peak value of the DC fluctuation when recording the converted data on the medium, and DSV value measuring means for measuring the DSV value when recording the converted data on the medium, 1T run length measuring means for measuring the maximum number of 1T repetitions when recording the converted data on a medium, and a plurality of kinds of converted data generated by the additional converting means for a plurality of kinds of the initial data The peak value, the DSV value, and the 1T run length value measured on the data are compared with each other, and both of these values are suppressed. A modulation circuit which is characterized by having a selection means for selecting an initial data as the initial data.

According to the invention of claim 18, in claim 17, the selecting means gives priority to the converted data of the plurality of types in the order in which the peak value and the DSV value are suppressed, and the priority is high. It is characterized in that the 1T run length value of the post-conversion data is compared with the set value in order from the first one, and the initial data of the post-conversion data in which the 1T run length value first falls below the set value is selected.

According to a nineteenth aspect of the present invention, in the eighteenth aspect, when there is no converted data whose 1T run length value is first less than the set value, the initial value of the converted data having the highest priority is selected. It is characterized by:

According to a twentieth aspect of the present invention, additional conversion means for adding at least 2 bits or more of initial data to the block data and then performing predetermined data conversion by the initial data and the block data, and the additional conversion means generate the additional data. Peak value measuring means for measuring the peak value of the DC fluctuation when recording the converted data on the medium, and DSV value measuring means for measuring the DSV value when recording the converted data on the medium, A 0/1 run length measuring means for measuring the maximum value of the run length of 0 or 1 when recording the converted data on the medium; and a number of 1T repetitions when recording the converted data on the medium. 1T run length measuring means for measuring the maximum value, and a plurality of types of converted data generated by the additional converting means for a plurality of types of the initial data. The peak value measured for, D
A modulation circuit comprising: SV value, 0/1 run length value and 1T run length value, respectively, and selecting means for selecting as initial data initial data such that these values are both suppressed. Is.

According to a twenty-first aspect of the present invention, in the twentieth aspect, the selecting means gives priority to the converted data of the plurality of types in the order in which the peak value and the DSV value are suppressed, and the priority is high. The 0/1 run length value and the set value of the converted data are compared and the 1T run length value and the set value are compared in order from the data, and both the 0/1 run length value and the 1T run length value are both It is characterized in that the initial data of the converted data that first falls below each set value is selected.

According to a twenty-second aspect of the present invention, in the twenty-first aspect, when there is no converted data in which both the 0/1 run length value and the 1T run length value are first lower than the respective set values, there is no priority. It is characterized in that the initial value of the converted data having the highest rank is selected.

According to a twenty-third aspect of the present invention, in the twenty-first aspect, when there is no post-conversion data in which both the 0/1 run length value and the 1T run length value first fall below the respective set values, It is characterized in that either one of the 0/1 run length value and the 1T run length value first selects the initial value of the converted data which is lower than the set value.

In the inventions of the above claims, the peak value of the DC fluctuation and the DSV value are suppressed, and the 0/1 run length value and / or the 1T run length value is further suppressed. Focusing on the redundancy of components and the suppression of adverse effects on Viterbi decoding, 0/1 run length value and 1
Only one or both of the T run length values may be suppressed. In this way, even if either or both of the 0/1 run length value and the 1T run length value are suppressed, a smooth reproduction operation can be realized.

Therefore, according to the invention of claim 11, in the information recording apparatus for modulating the block data and recording the modulated data on the medium, the modulating means for modulating the block data has at least 2 bits. After adding the above initial data, additional conversion means for performing predetermined data conversion by the initial data and block data, and 0 or 1 for recording the converted data generated by the additional conversion means on the medium. A 0/1 run length measuring means for measuring the maximum value of the run length, a 1T run length measuring means for measuring the maximum value of the number of 1T repetitions when the converted data is recorded on the medium, and a plurality of types of the above The 0/1 measured on a plurality of types of converted data generated by the additional conversion means with respect to the initial data
The present invention is characterized by further comprising: a selection unit that compares the run-length value and the 1T run-length value and selects the initial data such that these values are both suppressed as the initial data.

According to a twelfth aspect of the present invention, in an information recording apparatus for modulating block data and then recording the modulated data on a medium, the modulating means for performing the modulation has at least 2 bits or more for the block data. Additional conversion means for performing predetermined data conversion by the initial data and the block data after adding the initial data, and a run length of 0 or 1 when recording the converted data generated by the additional conversion means on the medium. The maximum value of 0
/ 1 run-length measuring means and the 0/1 run-length values measured for the plurality of types of converted data generated by the additional converting means for the plurality of types of the initial data are compared, and this value is suppressed most. Selecting means for selecting such initial data as the initial data.

According to a thirteenth aspect of the present invention, in the information recording apparatus for modulating the block data and recording the modulated data on the medium, the modulation means for modulating the block data has at least 2 bits or more. Additional conversion means for performing predetermined data conversion by adding the initial data and the initial data and the block data, and the maximum number of 1T repetitions when recording the converted data generated by the additional conversion means on the medium. A 1T run length measuring means for measuring a value is compared with the 1T run length value measured for a plurality of types of converted data generated by the additional converting means for a plurality of types of the initial data, and this value is most suppressed. Selecting means for selecting such initial data as the initial data.

According to a twenty-fourth aspect of the present invention, additional conversion means for adding at least 2 bits or more of initial data to the block data and then performing predetermined data conversion by the initial data and the block data, and the additional conversion means are generated. 0/1 run length measuring means for measuring the maximum value of the run length of 0 or 1 when recording the converted data on the medium, and the number of 1T repetitions when recording the converted data on the medium 1T run-length value measuring means for measuring the maximum value of 0, and the 0/1 run-length value and 1T run-length value measured with respect to a plurality of types of converted data generated by the additional conversion means with respect to a plurality of types of the initial data. And the selection means for selecting the initial data such that these values are suppressed together as the initial data. Having a modulation circuit, characterized in that.

According to a twenty-fifth aspect of the present invention, additional data converting means adds at least two bits of initial data to the block data, and then performs predetermined data conversion by the initial data and the block data, and the additional conversion means. 0/1 run length measuring means for measuring the maximum value of run length of 0 or 1 when recording the converted data on the medium, and a plurality of kinds of the initial data generated by the additional converting means. A modulation circuit comprising: a selection unit that compares the 0/1 run length values measured for a plurality of types of converted data, and selects initial data that minimizes the values as initial data. is there.

According to a twenty-sixth aspect of the present invention, additional data converting means adds at least 2 bits or more of initial data to the block data, and then performs predetermined data conversion by the initial data and the block data, and the additional conversion means. 1T when recording the converted data on the medium
Of 1T run length measuring means for measuring the maximum value of the number of repetitions of, and the 1T run length value measured for a plurality of types of converted data generated by the additional converting means for a plurality of types of the initial data, The modulation circuit is characterized by having selection means for selecting, as initial data, initial data such that this value is most suppressed.

The adverse effect on Viterbi decoding is that the 1T pattern (the minimum interval between the rising and falling edges of the recording signal)
Therefore, even if the number of 1T repetitions is not as large as the left, the 1T existing in the block
The larger the total number of, the greater the adverse effect on Viterbi decoding. Therefore, by selecting the initial value Tj that suppresses the total number of 1Ts existing in the block to be equal to or less than the predetermined set value, it is possible to suppress the adverse effect on the Viterbi decoding.

Therefore, claims 27 to 39 and claim 4
In the invention described in any one of claims 3 to 55, in the invention described in any one of claims 1 to 26, the 1T run length measuring means is replaced with a 1T number measuring means, or a 1T number measuring means is added together with the 1T run length measuring means. The information recording device and the modulation circuit.

Further, claims 40 to 42 and claim 56.
The inventions described in ˜58 describe the features of the invention described in each of the above claims as a superordinate concept. Here, "1
The “measured value of T” is a concept including a run length of 1T and the number of 1T.

By the way, as described above, the selection of the optimum initial data is made by comparing the respective elements of the peak value, the DSV value, the 0/1 run length value, the 1T run length value and the 1T number value. If these elements are simply compared, the value of any one of the elements greatly affects the selection of optimum initial data, and there is a possibility that appropriate initial data cannot be selected as optimum initial data. In order to prevent such an inconvenience, for example, in the invention of claim 2, first, each initial value is given superiority or inferiority depending on the magnitude of suppression of the peak value and the DSV value, and then 0/1, in descending order of priority. The run length value and the 1T run length value were compared so that the optimal initial data was selected.

However, according to this method, an initial value that is excellent in suppressing the peak value and the DSV value but inferior in suppressing the 0/1 run length value and the 1T run length value is not selected as the optimum initial value. On the contrary, an undesired event such that an initial value with poor suppression of peak value and DSV value but excellent suppression of 0/1 run length value and 1T run length value is selected as an optimum initial value rarely occurs. This may cause a problem that the selection accuracy of the optimum initial value is reduced.

Therefore, in the inventions of claims 59 to 66, weighting is set to each element of the peak value, DSV value, 0/1 run length value, 1T run length value and 1T number value, and this weighting is set for each element. The optimum initial value is selected by multiplying the value of. As a result, each element can be comprehensively and statistically evaluated, and thus the accuracy of selecting the optimum desired data can be improved.

That is, the invention of claim 59 is the information recording apparatus according to any one of claims 1, 4, 7, 27, 30, 34 and 40, wherein the selecting means measures the peak value of the converted data. , DSV value, 0/1 run length value, 1T run length value, and 1T number value are compared with the combinations defined in the claims, a predetermined weighting is set to these, and after the weighting is set. Is compared with each other, and the optimum initial data is selected.

According to a 60th aspect of the present invention, in the information recording apparatus according to the 59th aspect, the selecting means multiplies the value of each element by a predetermined weighting value, adds the multiplication values, and adds the addition values. Select the initial data with the smallest value,
It is characterized by

According to a 61st aspect of the present invention, in the information recording apparatus according to the 60th aspect, said selecting means multiplies the value of each element except said DSV value by a weighting value and then adds these multiplication values, In comparing the magnitudes of the added values, if the added values are the same, the initial data having the smaller DSV value is selected.

The invention of claim 62 is based on claims 59 to 61.
In the information recording apparatus according to any one of items 1 to 5, the 1T number value is reduced by performing a predetermined filtering process,
It is characterized in that this value is compared with the values of other elements.

The invention of claim 63 is based on claims 14, 17,
In the modulation circuits described in 20, 43, 46, 50, and 56, the selecting unit includes the peak value, the DSV value, the 0/1 run length value, the 1T run length value, and the 1T number value measured for the converted data. Each element of
When comparing the combinations defined in the claims, a predetermined weighting is set for these, and each element after weighting is compared, and the optimum initial data is selected.

According to a sixty-fourth aspect of the present invention, in the modification circuit according to the sixty-third aspect, the selecting means multiplies the value of each element by a predetermined weighting value, adds these multiplication values, and adds the added value. It is characterized in that the initial data that minimizes is selected.

According to a sixty-fifth aspect of the present invention, in the modification circuit according to the sixty-fourth aspect, the selecting means multiplies the value of each element excluding the DSV value by a weighting value and then adds these multiplication values, and the addition is performed. In comparing the magnitudes of the values, if the added values are equal, the initial data having the smaller DSV value is selected.

The invention of claim 66 is based on claims 63 to 65
In the change circuit described in any one of 1) to 1), the 1T number value is subjected to predetermined filtering to reduce the value, and then this value is compared with the values of other elements.

The features of the present invention will be further clarified by the following description of the embodiments.

The "additional conversion means" in the claims means the T0-15 addition conversion circuits 1a to 1d in the embodiment.
Corresponds. The "peak value measuring means" in the claims corresponds to the recording time data string conversion circuit 2 and the peak value measuring circuit 4 in the embodiment. The "DSV value measuring means" in the claims is the recording data string conversion circuit 2 in the embodiment.
Corresponds to the DSV value measuring circuit 3. "0" in the claims
The "/ 1 run length value measuring means" corresponds to the recording data string conversion circuit 2 and the 0/1 run length measuring circuit 5 in the embodiment. The "1T run length measuring means" in the claims is the recording data string conversion circuit 2 in the embodiment.
Corresponds to the 1T run length measuring circuit. The "1T number measuring means" in the claims corresponds to the recording data string conversion circuit 2 and the 1T number measuring circuit 9 in the embodiment. The "selecting means" in the claims is the selecting circuit 7 in the embodiment.
And correspond.

However, the following embodiment is merely one embodiment of the present invention, and the meanings of the terms of the present invention and each constituent element are limited to those described in the following embodiment. Not something.

[0053]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

First, FIG. 1 shows the structure of a magneto-optical disk according to the embodiment. A spiral groove is formed on the disk 10 from the outer peripheral portion to the inner peripheral portion.
As a result, a spiral flat portion (land) is formed in the region between the grooves. Address regions are assigned to the grooves and lands at fixed rotation angles, and the grooves and lands meander (wobble) in the disk radial direction as shown in FIG. This wobble includes a wobble for holding an address on the disc as information and a wobble for generating a clock at the time of recording / reproducing. Of these, the wobble for address has a wobble waveform modulated according to the address information. Also, the wobble for clock generation is
The waveform has a constant cycle and constant amplitude. Therefore, when the light beam scans this address area, the address signal and the clock signal can be obtained by the reflected light.

Information is magneto-optically recorded in the data area between the address areas. As shown, the recording area is divided into a plurality of zones in the disk radial direction. The disk rotation speed during recording and playback in each zone is constant angular velocity,
The angular velocity of one zone and the angular velocity of another zone are different (zone CAV). Therefore, the address areas are aligned in the disk radial direction within each zone, but the address areas of one zone and the other zones are not aligned on the disk diameter. However, since the start position of each zone is on the disk diameter in all zones, the address areas at the start positions are aligned on the disk diameter in all zones.

FIG. 3 shows a block diagram of a recording system of such a magneto-optical disk. In the figure, 20 is a spindle motor that drives the disk 10 to rotate, 30 is a spindle servo circuit that controls the motor so that the angular velocity is assigned to each zone based on the wobble signal from the disk, and 40 is a groove or land beam. An optical head 50 for irradiating on the top, a magnetic head 50 for applying a magnetic field to the groove or land position where the beam is irradiated by the optical head, and an amplifier 60.

Reference numeral 70 denotes a modulation circuit which modulates the basic data to be recorded and then inputs this to the magnetic head 50 via the amplifier 60. The structure and modulation method of the modulation circuit 70 will be described later in detail.

Reference numeral 80 is a matrix circuit for generating a tracking error signal, a focus error signal, an RF signal, and a wobble signal from the output of a photodetector which receives the reflected beam from the disk 10, and 90 is a groove or land which receives the tracking error signal. A tracking control circuit for correcting the track deviation of the beam on the upper side, and a focus control circuit 100 for receiving the focus error signal and correcting the focus deviation of the beam on the groove or land.

Reference numeral 110 is an address detection circuit for receiving a wobble signal to detect an address, 120 is a PLL (Phase Locked Loop) circuit for receiving a wobble signal to generate a recording clock and supplying it to the modulation circuit 70, and 130 is an address. It is a timing controller that receives a signal, determines the recording start timing on the groove or land, and supplies the timing signal to the modulation circuit 70.

The basic data supplied to the modulation circuit 70 is modulated by the modulation circuit 70, which will be described later.
Depending on the recording clock from the L circuit, NRZ (Non Retu
rn to Zero) is converted into a recording signal (rectangular wave).
The recording signal is supplied to the amplifier 60 in response to the timing signal from the timing controller 130, whereby the basic data is recorded in the data area on the groove or land shown in FIG.

Here, the modulation circuit 70 modulates the basic data in block units obtained by dividing the data to be recorded in one data area shown in FIG. 1 by a predetermined number of bits. The timing controller 130 outputs a timing signal so that the one block of the modulated data is sequentially recorded from the start position of the data area. Therefore, the modulated data for one block is recorded on the groove or land so as to be sequentially assigned to one data area.

FIG. 4 shows a block diagram of a reproducing system of such a magneto-optical disk. The same parts as those of the recording system are designated by the same reference numerals and the description thereof will be omitted.

In the figure, 140 is a matrix circuit 8.
An AD conversion circuit for converting the RF signal from 0 into digital data, a Viterbi decoding circuit 150 for Viterbi decoding the AD converted signal to generate a reproduction signal (rectangular wave), and 160 demodulating the Viterbi decoded reproduction signal. And a demodulation circuit for generating basic data. Note that the Viterbi decoding circuit 150 uses PR
This is a well-known binary signal generation circuit based on ML (Partial Response Maximum Likelihood).

The demodulation circuit 160 is the modulation circuit 70.
The basic data is demodulated by performing the reverse process of. That is, the demodulation circuit 160 includes the timing controller 13
The timing signal from 0 identifies the starting position of the data area. Then, the reproduced signal is subjected to NRZ inverse conversion by the reproduced clock from the PLL circuit 120, and the data obtained by this is subjected to demodulation reverse to the modulation of the modulation circuit 70.

FIG. 5 shows the modulation circuit 70 in the recording system.
Shows the configuration of. In the figure, reference numeral 71 denotes an error correction circuit for adding an error correction code to the base data according to a predetermined error correction method,
Reference numeral 72 denotes an adaptive modulation circuit that performs adaptive modulation, which will be described later, on the data for each block to which the error correction code is added, 73 is a synchronous data generation circuit that generates a fixed pattern data string that can be a synchronization signal, 74 Is a switching circuit that receives a timing signal from the timing controller 130 and adds a synchronization signal to the beginning of a block of data recorded in the data area, and 75 performs NRZ conversion on the data output from the switching circuit 74. This is an NRZ conversion circuit that supplies this to the amplifier 60.

Therefore, the modulation circuit 70 generates a recording signal in which the synchronizing signal is added to the head of the data in each data area. Then, this recording signal is sent to the amplifier 60.
And then applied to the magnetic head 50 for recording.

FIG. 6 shows the demodulation circuit 16 in the reproduction system.
The structure of 0 is shown. In the figure, reference numeral 161 denotes an NRZ inverse conversion circuit for receiving a timing signal from the timing controller 130 and performing NRZ inverse conversion only on a reproduction signal of a data area following the address area, and 162 detects synchronous data from the inversely converted data. A block data extraction circuit for extracting only block data, 163 an adaptive demodulation circuit for performing adaptive demodulation described below on the block data,
An error correction circuit 164 performs error correction on the demodulated data using an error correction code. Therefore, the demodulation circuit 70 sequentially outputs the block data for which error correction has been performed as basic data.

7 and 8 show the adaptive modulation circuit 7 described above.
2 and the modulation method in the adaptive demodulation circuit 163 are shown. First, the modulation method in the adaptive modulation circuit 72 will be described with reference to FIG.

One block of data is divided by a predetermined number of bits (D0 to DL-1). Initial data Tj having the same number of bits as the divided D0 to DL-1 is added to the data of one block. An exclusive OR is calculated for each of Tj and D0 for each bit to obtain D'0.
To calculate. Then, the exclusive OR is similarly calculated between the D'0 and the next D1 to calculate D'1. Similarly, the exclusive OR calculation is repeated up to D′ L−1 to obtain converted data for one block of data.

Here, there are 2 N patterns of the Tj, where the number of bits of the Tj is N bits. The adaptive conversion circuit 72 in FIG.
The above exclusive OR calculation is performed on the powers of Tj, and 2
Then, N converted data items are calculated. Then, regarding the converted data, the peak value variation of the DC component, the DS
V, 0/1 run length and 1T run length are compared, and among these, the most preferable Tj as a recording signal and its converted data are selected, and this is output to the NRZ conversion circuit 73 as recording data.

The peak value fluctuation of the DC component in the adaptive conversion circuit 72, the comparison of DSV, 0/1 run length and 1T run length, and the selection of the most preferable Tj will be described later in detail.

Next, the adaptive demodulation circuit 16 will be described with reference to FIG.
The demodulation method in 3 will be described. Of the data of one block extracted by the block data extraction circuit 162,
An exclusive OR is calculated bit by bit for the first Tj and the next D'0 to calculate D0. Similarly, D'0 and D'1
An exclusive OR is calculated between and to calculate D1. Similarly, the exclusive OR is calculated up to DL-1 to obtain inverse-transformed data for one block of data.

The adaptive demodulation circuit 163 in FIG. 6 only performs the inverse conversion described in FIG. That is, the reverse transformation causes the leading Tj to disappear,
Only playback data is available. The reproduced data is output to the error correction circuit 164, and after error correction is performed here,
It is decoded into reproduction data by the decoding circuit in the subsequent stage.

FIG. 9 shows the configuration of the adaptive modulation circuit 153 shown in FIG. In this adaptive modulation circuit, the initial data Tj in FIG. 7 is set to 4 bits, and therefore the conversion shown in FIG. 7 is performed for 16 types of Tj, and the peak value fluctuation of the DC component, DSV, 0/1 run is obtained for each conversion result. The length is compared.

In the figure, reference numerals 1a to 1d denote T0-16 conversion circuits which add 16 kinds of initial values T0 to T15 to block data and perform the conversion shown in FIG. Where T0-1
The 5 addition conversion circuits 1a to 1d are arranged in 16 stages corresponding to 16 types of Tj. Therefore, 16 stages of T0-
The recording time data string conversion circuit 2 receiving the outputs of the 15 addition conversion circuits 1a to 1d, the DSV value measurement circuit 3, the peak value measurement circuit 4 and the 0/1 run length measurement circuit 5 are also arranged in 16 stages.

Reference numeral 2 is a recording data string conversion circuit,
5 The data for one block converted by the additional conversion circuits 1a to 1d is converted into a signal form for recording on the disc. That is, in the present embodiment, the additional-converted data is NRZ-converted and recorded on the disc, so that in the recording data string conversion circuit 2, T0-15.
The data for one block supplied from the additional conversion circuits 1a to 1d is NRZ-converted, and the recording signal (rectangular wave) after the NRZ conversion is digitally expressed by a data string of 0 or 1. For example, a data string of 1 is output in response to the recording clock in the section where the recording signal is rising, and a data string of 0 is output in the section where the recording signal is falling according to the recording clock.

Reference numeral 3 denotes a DSV value measuring circuit, which is the DSV of the converted data with the data string from the recording data string converting circuit 2 and the initial value Tj selected immediately before by the selecting circuit 7.
The DSV value of the recording signal is measured based on the value and.
Reference numeral 4 denotes a peak value measuring circuit, which is based on the data string from the recording data string converting circuit 2 and the peak value of the converted data with the initial value Tj selected immediately before by the selecting circuit 7, and outputs the direct current of the recording signal. The peak value (absolute value) of fluctuation is detected and held.

Reference numeral 5 is a 0/1 run length measuring circuit, which includes the data string from the recording data string converting circuit 2 and the 0/1 run length information of the converted data according to the initial value Tj selected immediately before by the selecting circuit 7. Based on, the number of consecutive 1s or 0s of the recording signal is measured. This run length information is obtained by converting the data string of the immediately preceding block by the initial value Tj selected immediately before and converting the length of 1 or 0 at the end of the data string converted by the recording time data string conversion circuit 2. It is information to show. The 0/1 run-length measuring circuit 5 refers to the last 1 or 0 and the first 1 or 0 of the data string from the recording data string conversion circuit 2 and refers to the connected portion of the two data strings. 0 or 1
Measure the run length of. Then, the run length of this concatenated portion is compared with the run length of 1 or 0 existing in the data string for one block data, and the longest run length is held from these.

A selection circuit 7 compares the DSV value, the peak value and the run length supplied from the 16-stage DSV value measuring circuit 3, the peak value measuring circuit 4 and the 0/1 run length measuring circuit 5, Determine which step value is most preferable. The details of the control of the selection circuit 7 will be described later.

Reference numeral 8 denotes a Tj addition conversion circuit, which adds the initial value Tj of the stage selected by the selection circuit 7 to the head of the block data to perform the conversion shown in FIG. This is supplied to the NRZ conversion circuit 73.

A selection circuit 170 supplies the block data of the memory 180 to the Tj additional conversion circuit 8 and the block data of the memory 190 to the T0-15 additional conversion circuits 1a to 1d. Reference numeral 180 denotes a memory, which is the selection circuit 7
The block data targeted for comparison / selection is stored. A memory 190 stores the next block data to be compared / selected by the selection circuit 7.

Therefore, the error-corrected block data supplied to the adaptive conversion circuit 72 is first stored in the memory 190, and the optimum initial value Tj is selected by the conversion circuit / measurement circuit of 16 stages and the selection circuit 7. Be targeted. Then, when such selection is completed, the block data stored in the memory 190 is transferred to the memory 180 and the memory 1
The next block data is stored in 90. The selection circuit 170, the memory 180, and the memory 190 are not shown in the block diagram of the recording system in FIG.

FIG. 10 shows a control flowchart of the selection circuit 7. When 16 kinds of DSV values, peak values and run length values are supplied from the 16 stages of the DSV measuring circuit 3, the peak value measuring circuit 4 and the 0/1 run length measuring circuit 5 to the selecting circuit 7, first, step 101 In, the priority order of each stage is set in order from the smallest peak value. Here, when there are a plurality of stages having the same peak value, the one having a smaller DSV value is ranked higher. Furthermore, when the DSV values are also equal, T0-1
5 The order of the additional conversion circuits 1a to 16 is followed. That is, in FIG. 9, the T0 addition conversion circuit 1a is the highest, and
The additional conversion circuit 1d is the lowest.

Next, in step 102, the set value L01 of 0/1 run length is set, and step S103
The variable K is set to 0 at. Here, L01 is a run length threshold value of 0 or 1 which is an allowable range of a DC component generated when data is recorded on a disc.

When L01 is set in this way,
Next, in step S104, the longest run length value RunLM (0) of the stage of the K = 0th priority is compared with L01, and the run length value RunLM (0) is L0.
If it is smaller than 1, the process proceeds to step S107, and the initial value T0 of the stage of the rank K = 0 is selected as the most preferable initial value. On the other hand, if the run length value RunLM (0) is L01 or more, steps S105 to S105
Proceeding to 106, the run length value RunLM (1) of the next priority stage (stage of K = 1) is compared with L01.
Then, the run length value RunLM (1) is L0 here.
When it is smaller than 1, the initial value T1 of the stage of K = 1
Is selected as the most preferable initial value.

In the same manner, the lower rank (K = 2 to K = 2)
Runlength value RunLM with 15 priority levels)
(K) and L01 are compared in order. Such comparison is
The process is repeated until the run length value RunLM (K) is smaller than L01 (steps S104 to S1).
06). Then, the run length value RunLM (K) is L
When a stage smaller than 01 is detected, the initial value T of that stage is detected.
k is chosen as the most preferred initial value.

The run length value RunLM (K) is L01 even if the determination in steps S104 to S105 is performed up to K = 15, that is, for the stage having the lowest priority.
If no smaller step is detected, step S1
Proceeding to 08, the initial value T0 of the highest priority stage of K = 0 is selected as the preferred initial value.

When the most preferable initial value is selected as described above, the selection circuit 7 selects it as the Tj addition conversion circuit 8
Supply to. At the same time, the DSV value, the peak value, and the 0/1 run length information of the selected stage are set to the DSV of 16 stages.
The value measurement circuit 3, the peak value measurement circuit 4, and the 0/1 run length measurement circuit 6 are initialized (step S10).
9).

By such selection control, the selection circuit 7 can select the initial value Tk such that the peak value, the DSV value, and the 0/1 run length value are the smallest. Therefore, when the block data is converted with the initial value Tk and recorded on the disk, the peak value of the DC fluctuation,
The promotion of the DSV value and the DC component can be suppressed at the same time, and a stable recording / reproducing operation can be realized.

FIG. 11 shows another configuration example of the adaptive modulation circuit 153 in FIG. Such a configuration example and the above FIG.
The difference from the example of the configuration is only the 1T run length measuring circuit 6. That is, in the configuration example, 0 / of FIG.
A 1T run length measuring circuit 6 is arranged in place of the 1 run length measuring circuit 5. The selection circuit 7 compares the 1T run length value from the 1T run length measurement circuit 6 with the peak value variation of the DC component, DSV, and selects the most preferable initial value Tj. The other configuration is the same as the configuration example of FIG. 9 described above, and therefore the description thereof is omitted here.

The 1T run length measuring circuit 6 outputs 1 of the converted data by the data string from the recording data string converting circuit 2 and the initial value Tj selected immediately before by the selecting circuit 7.
1T of the recording signal based on the T run length information
Measure the number of repetitions (minimum section of rising and falling). The 1T run length information indicates the number of 1T repetitions at the end of the data string obtained by converting the data string of the immediately preceding block with the initial value Tj selected immediately before and converting the data string by the recording data string conversion circuit 2. Information. The 1T run length measuring circuit 6 refers to the last 1T run length and the first 1T run length of the data string from the recording data string conversion circuit 2 and refers to the 1T run in the concatenated portion of the two data strings. Measure the length. Then, the 1T run length of this concatenated portion is compared with the 1T run length existing in the data string for one block data, and the longest 1T run length among these is held.

FIG. 12 shows a selection control flowchart of the selection circuit 7. This flowchart is different from the flowchart of FIG. 10 in steps S202, S204 and S202.
209 is different.

That is, in step S202, 1
Set the threshold of T run length, and this and 1T of each stage
The maximum run length value Run1TM (K) is compared in order from the highest priority. And step S2
From 04 to S206, 1T Run Length Run1TM
(K) and L1t are compared, and 1T run length Run1
If there is a stage satisfying TM (K) <L1t, the initial value Tk of the stage is set as the most preferable initial value (step S207),
On the other hand, if there is no stage that satisfies 1T run length Run1TM (K) <L1t, the initial value of the stage with the highest priority is selected as the most preferable initial value (step S20).
8).

The selected initial value is supplied to the Tj addition conversion circuit 8. At the same time, the DSV of such initial value stage
Value, peak value and 1T run length value are calculated in step S
At 209, the 16-stage DSV value measuring circuit 3, the peak value measuring circuit 4, and the 1T run length measuring circuit 6 are initialized.

By such selection control, the selection circuit 7 can select the initial value Tk such that the peak value, the DSV value, and the 1T run length value are the smallest. Therefore, when the block data is converted with the initial value Tk and recorded on the disc, the peak value of the DC fluctuation, D
It is possible to suppress adverse effects on the SV value and Viterbi decoding at the same time, and to realize stable recording / reproducing operation.

FIG. 13 shows still another configuration example of the adaptive modulation circuit 153 in FIG. In this configuration example, both the 0/1 run length measuring circuit 5 and the 1T run length measuring circuit 6 are arranged. The selection circuit 7 compares the 0/1 run length value and the 1T run length value from the 0/1 run length measurement circuit 5 and the 1T run length measurement circuit 6 with the peak value fluctuation value and the DSV value of the DC component. , The most preferable initial value Tj is selected. The configuration of each part is the same as the configuration example of FIGS. 9 and 11 described above, and thus the description thereof is omitted here.

FIG. 14 shows the selection circuit 7 in the configuration example.
7 shows a selection control flowchart of The flowchart is different from the flowcharts of FIGS. 8 and 10 in steps S302, S304, and S309.

That is, in step S302, 0
/ 1 run length and 1T run length threshold L
01 and L1t are set, and the maximum value Run1TM of 0/1 run length and 1T run length at each stage is set.
(K) is compared in descending order of priority. Then, in steps S304 to S306, the 0/1 run length RunLM (K) and the 1T run length Run are executed.
1TM (K) is compared with L01 and L1t, and 0 /
If there is a stage that simultaneously satisfies both 1 run length RunLM (K) <L10 and 1T run length Run1TM (K) <L1t, the initial value Tk of that stage is set as the most preferable initial value (step S307). On the other hand, 0/1 run length RunLM (K) <L10 and 1T run length R
If there is no stage that satisfies both un1TM (K) <L1t at the same time, the initial value of the stage with the highest priority is selected as the most preferable initial value (step S308).

The selected initial value is supplied to the Tj addition conversion circuit 8. At the same time, the DSV of such initial value stage
The value, the peak value, the 0/1 run length value, and the 1T run length value are set in the DS of 16 stages in step S309.
The V value measuring circuit 3, the peak value measuring circuit 4, the 0/1 run length measuring circuit 5 and the 0/1 run length measuring circuit 6 are initialized respectively.

By such selection control, the selection circuit 7 can select the initial value Tk such that the peak value, the DSV value, the 0/1 run length value and the 1T run length value are all the smallest. Therefore, when the block data is converted with the initial value Tk and recorded on the disc, the peak value of the DC fluctuation, the DSV value, the promotion of the DC component, and the adverse effect on the Viterbi decoding can be suppressed at the same time. Therefore, stable recording / reproducing operation can be realized.

By the way, in the above-described embodiment, the peak value of the DC fluctuation and the DSV value are suppressed, and the 0/1 run length value and / or the 1T run length value is further suppressed. If attention is paid only to the redundancy and the suppression of the adverse effect on the Viterbi decoding, either or both of the 0/1 run length value and the 1T run length value may be suppressed. For example, when only one of the 0/1 run length value and the 1T run length value is suppressed, the 0/1 run length value or the 1T run length value of each of 0 to 15 stages is compared, and , The minimum value of 0/1 run length value or 1T run length value of the stage initial value may be selected by the selection circuit 7.

Further, in the case of suppressing both the 0/1 run length value and the 1T run length value, as shown in FIG. 15, in the case of FIG. Similarly, each step is given a priority order (step S401), and it is determined in order from the highest priority order whether the 1T run length is smaller than the set value (steps S402 to S406). If there is one, the initial value of that stage is selected (step S407), and if there is no smaller value than the set value, the initial value of the stage with the highest priority is selected (step S408).

In the above embodiment, the 1T run length value (the number of 1T repetitions) is compared with the set value, and the DC
It was intended to suppress the redundancy of components and the adverse effect on Viterbi decoding. However, such an adverse effect on Viterbi decoding is due to the existence of the 1T pattern (the minimum interval between the rising and falling edges of the recording signal) in the first place. Therefore, even if the number of 1T repetitions does not reach the set value, If there are a large number of 1Ts present therein, the adverse effect on Viterbi decoding will be increased. Therefore, in order to solve the problem more fundamentally, it is preferable to select the initial value Tj that suppresses the number of 1Ts existing in the block to a predetermined set value or less.

FIG. 16 shows an initial value T based on the number of 1T.
An example of the configuration of the adaptive modulation circuit 153 for selecting j is shown.

First, FIG. 16 shows another configuration example of the adaptive modulation circuit 153 in FIG. An example of such a configuration is
The 1T run length measuring circuit 6 in the configuration example of FIG. 11 is replaced with a 1T number measuring circuit 9. The 1T number measuring circuit 9 counts the number of 1T existing in the data string from the recording data string converting circuit 2. The selection circuit 7 determines the number of 1T and the peak value variation of the DC component, D
Comparing SV with a predetermined set value, the most preferable initial value T
Select j. The other configuration in FIG. 16 is
Since it is the same as the configuration example of FIG. 11, the description thereof is omitted here.

FIG. 17 shows a selection control flowchart of the selection circuit 7. This flowchart is different from the flowchart of FIG. 12 in steps S502, S504 and S.
509 is different.

That is, in step S502, 1
Set a threshold value for the number of Ts, and this and the 1T number value N of each stage.
um1TM (K) is compared in order from the highest priority. Then, in steps S504 to S506, 1
The T number value Num1TM (K) is compared with L1tn, and 1
If there is a stage that satisfies the T number value Num1TM (K) <L1tn, the initial value Tk of the stage is set as the most preferable initial value (step S507), while the 1T number value Num1TM is set.
If there is no stage satisfying (K) <L1tn, the initial value of the stage having the highest priority is selected as the most preferable initial value (step S508).

The selected initial value is supplied to the Tj addition conversion circuit 8. At the same time, the DSV value and the peak value of the stage of the initial value are, in step S509, the DSV value measuring circuit 3 of the 16 stages, the peak value measuring circuits 4 and 1T.
The number measuring circuit 6 is initialized respectively.

By such selection control, the selection circuit 7 can select the initial value Tk such that the peak value, the DSV value, and the 1T number value are the smallest. Therefore, when the block data is converted with the initial value Tk and recorded on the disk, adverse effects on the peak value of the DC fluctuation, the DSV value, and the Viterbi decoding can be suppressed at the same time, and stable recording / reproduction can be performed. The operation can be realized.

FIG. 18 shows still another configuration example. In this configuration example, both the 0/1 run length measuring circuit 5 and the 1T number measuring circuit 9 are arranged. The selection circuit 7 includes the 0/1 run length measuring circuit 5 and the 1T number measuring circuit 9
The most preferable initial value Tj is selected by comparing the 0/1 run-length value and the 1T number value from (3) with the peak value fluctuation value of the DC component and the DSV value.

FIG. 19 shows a selection circuit 7 in the configuration example.
7 shows a selection control flowchart of This flowchart is different from the flowchart of FIG. 17 in step S6.
02, S604 and S609 are different.

That is, in step S602, 0
The thresholds L01 and L1tn for the / 1 run length and the 1T number are set, and this and the 0/1 run length and the 1T number value of each stage are compared in order from the highest priority. Then, in steps S604 to S606, 0
/ 1 run length RunLM (K) and 1T number value N
um1TM (K) is compared with L01 and L1tn, and 0/1 run length RunLM (K) <L01,
If there is a stage that simultaneously satisfies both 1T number value Run1TM (K) <L1tn, the initial value Tk of that stage is set as the most preferable initial value (step S607). On the other hand, 0/1 run length RunLM (K) <L10 and 1T number value Nu
If there is no stage that satisfies both m1TM (K) <L1t at the same time, the initial value of the stage with the highest priority is selected as the most preferable initial value (step S608).

The selected initial value is supplied to the Tj addition conversion circuit 8. At the same time, the DSV of such initial value stage
Value, peak value, 0/1 run length value, step S6
At 09, the 16-stage DSV value measuring circuit 3, the peak value measuring circuit 4, and the 0/1 run length measuring circuit 5 are initialized.

By such selection control, the selection circuit 7 can select the initial value Tk such that the peak value, the DSV value, the 0/1 run length value, and the 1T number value are all the smallest. Therefore, when the block data is converted with the initial value Tk and recorded on the disc, the peak value of the DC fluctuation, the DSV value, the promotion of the DC component, and the adverse effect on the Viterbi decoding can be suppressed at the same time. Therefore, stable recording / reproducing operation can be realized.

FIG. 20 shows still another configuration example. In such a configuration example, in addition to the 0/1 run length measuring circuit 5 and the 1T run length measuring circuit 6, a 1T number measuring circuit 9 is arranged. The selection circuit 7 uses the 0/1 run length measurement circuit 5, the 1T run length measurement circuit 6 and the 1T number measurement circuit 9 to output the 0/1 run length value, the 1T run length value and the 1T number value, and the peak of the DC component. Value fluctuation value, D
The SV values are compared and the most preferable initial value Tj is selected.

FIG. 21 shows the selection circuit 7 in this configuration example.
7 shows a selection control flowchart of This flowchart is different from the flowchart of FIG. 19 in step S7.
02, S704 and S709 are different.

That is, in step S702, 0
/ 1 run length, 1T run length, and 1T number threshold values L01, L1t, and L1tn are set, and 0/1 run length, 1T run length, and 1T number value of each stage are set in descending order of priority. Compare in order. Then, in steps 704 to S706, 0/1 run length RunLM (K), 1T run length L1T
M (k) and 1T number value Num1TM (K) and L0
1, L1tn and L1tn are compared, and 0/1 run length RunLM (K) <L01, 1T run length Run1TM (K) <L1t, and 1T number value Run1T
If there is a stage that simultaneously satisfies all of M (K) <L1tn, the initial value Tk of the stage is set as the most preferable initial value (step S707). On the other hand, 0/1 run length RunLM
(K) <L01 and 1T run length Run1TM
(K) <L1t and 1T number value Run1TM (K) <L
If there is no stage that satisfies all 1tn at the same time, the initial value of the stage with the highest priority is selected as the most preferable initial value (step S708).

The selected initial value is supplied to the Tj addition conversion circuit 8. At the same time, the DSV of such initial value stage
The value, the peak value, the 0/1 run length value, and the 1T run length value are set to the DS of 16 stages in step S709.
V value measuring circuit 3, peak value measuring circuit 4, 0/1 run length measuring circuit 5 and 1T run length measuring circuit 6
Are initialized respectively.

By such selection control, the selection circuit 7 can select the initial value Tk such that the peak value, the DSV value, the 0/1 run length value, the 1T run length and the 1T number value are all the smallest. Therefore, when the block data is converted with the initial value Tk and recorded on the disc, the peak value of the DC fluctuation, the DSV value, the promotion of the DC component, and the adverse effect on the Viterbi decoding can be suppressed at the same time. Therefore, stable recording / reproducing operation can be realized.

In the above, the peak value of DC fluctuation and D
While suppressing SV value, 0/1 run length value,
Although the 1T run length and / or the 1T number value are suppressed, if attention is paid only to the redundancy of the DC component and the suppression of the adverse effect on the Viterbi decoding, the 0/1 run length value, 1
Any or all of the T run length value and the 1T number value may be suppressed. For example, one of these
If only one is suppressed, 0/1 run length value, 1T run length value or 1 for each of 0 to 15 stages
The T count values may be compared, and the minimum value of 0/1 run length value, 1T run length value, or the initial value of the stage of the 1T count value may be selected by the selection circuit 7.

FIG. 22 shows a control flowchart of the selection circuit 7 in the case of suppressing both the 0/1 run length value and the 1T run length number value. In such a control flowchart, the 0T run lengths are sorted in ascending order, and each step is prioritized in the same manner as in FIG. 10 (step S801). Is smaller than the set value (steps S802 to S806), and if there is one smaller than the set value, the initial value of the stage is selected (step S80).
7) If there is no smaller value than the set value, the initial value of the stage with the highest priority is selected (step S808).

By this selection control, the selection circuit 7 becomes 0
It is possible to select the initial value Tk such that both the / 1 run length value and the 1T number value are the smallest. Therefore, when the block data is converted with the initial value Tk and recorded on the disc, the promotion of the DC component and the adverse effect on the Viterbi decoding can be suppressed at the same time, and a stable recording / reproducing operation is realized. be able to.

Although various embodiments of the present invention have been described above, the present invention is not limited to these embodiments and various modifications can be made. For example, in the configuration examples of FIG. 9, FIG. 11, FIG. 13, FIG. 16, FIG. 18 and FIG. 20 described above, the circuits of 16 stages are arranged by making each circuit independent for 16 types of initial values. It is not necessary to make each circuit independent, and one circuit may be shared to perform processing for 16 types of initial values.

Further, the above-mentioned FIG. 9, FIG. 11, FIG. 13, and FIG.
In the configuration examples of FIGS. 6, 18 and 20, 16 types of initial values are set with the initial value being 4 bits, but the number of bits of the initial value and the number of patterns of the initial value are not limited to this. Alternatively, other numbers of bits and other numbers of patterns can be adopted.

In the selection control of FIG. 14, 0 /
When there is no stage that satisfies both 1 run length RunLM (K) <L10 and 1T run length Run1TM (K) <L1t at the same time, the initial value of the stage with the highest priority is simply selected ( Step S308)
In such a case, 0/1 run length RunLM (K) <
L10 and 1T run length Run1TM (K) <L1
It is also possible to select the initial value of the stage that first satisfies either one of t. By controlling in this way, the selection circuit 7 can select the initial value Tk such that either the 0/1 run length value or the 1T run length value becomes smaller in addition to the peak value and the DSV value. In addition to the peak value of direct current fluctuation and the DSV value, either the promotion of the DC component or the adverse effect on Viterbi decoding can be suppressed at the same time.

Similarly, in the selection control of FIG. 18, 0
/ 1 run length RunLM (K) <L10 and 1T number value Num1TM (K) <L1tn If there is no stage that satisfies both at the same time, the initial value of the stage with the highest priority is simply selected. (Step S608), in such a case, 0/1 run length RunLM (K) <L
Of 10 and 1T number value Num1TM (K) <L1tn, the initial value of the stage that first satisfies either one may be selected. When controlled in this way, the selection circuit 7
Is an initial value Tk such that the 0/1 run length value or the 1T number value is smaller than the peak value and the DSV value.
Therefore, in addition to the peak value of the DC fluctuation and the DSV value, either the promotion of the DC component or the adverse effect on Viterbi decoding can be suppressed at the same time.

Further, in the selection control of FIG. 20, 0
/ 1 run length RunLM (K) <L10, 1T run length Run1TM (K) <L1t, and 1T number value Num1TM (K) <L1tn, if there is no step that satisfies all at the same time, the priority is simply the highest. Although the initial value of the higher step is selected (step S708), in such a case, 0/1 run length RunLM (K) <L10
And 1T run length Run1TM (K) <L1t,
Of the 1T number value Num1TM (K) <L1tn, the initial value of the stage that first satisfies any one may be selected. By controlling in this way, the selection circuit 7 can select the initial value Tk such that either the 0/1 run length value or the 1T number value becomes smaller in addition to the peak value and the DSV value, and therefore the direct current Peak value of fluctuation and DSV
In addition to the value, either promotion of the DC component or adverse effect on Viterbi decoding can be suppressed at the same time.

By the way, in the above embodiment, the priority is set by the peak value and the DSV value, and the 0/1 run length value, the 1T run length value or the 1T number value is compared from the higher order of priority. However, instead of this, it is also possible to set a weight to each of these elements, compare the values of the elements according to the weight, and select the minimum initial value. Here, the weighting value may be determined from the result of repeated measurement, and for example, various measurement values may be statistically processed to determine the optimum weighting value.

The initial value selection processing by setting the weighting values will be described below. FIG. 23 is a flowchart of such selection processing. Such a flowchart corresponds to the block diagram of FIG. That is, a peak value, a DSV value, a 0/1 run length value, or a 1T run length value is supplied to the selection circuit 7 as a comparison element. The selection circuit 7 processes these comparison elements according to the flowchart of FIG.

First, in step S901, the peak value,
The 0/1 run length value and the 1T run length value are respectively multiplied by the weighting values A, B and C, and these are added to calculate Calc (i) as the addition result. The addition result is T0 addition conversion circuit 1a to T15 addition conversion circuit 1d.
Peak value from the circuit system of 16 stages divided by
This is performed for the / 1 run length value and the 1T run length value. Therefore, as a result of the processing in step S901, the addition results Calc (0) to Cal for each stage are calculated.
c (15) is calculated.

Next, in step S902, the magnitude of each addition result is compared. The size comparison is performed on the adjacent stages. That is, Calc (0) and Calc
(1), Calc (2) and Calc (3), ..., C
A magnitude comparison is made between alc (14) and Calc (15).

The size comparison is performed according to the processing shown in FIG.
That is, in step S921, the magnitudes of the two addition results are compared. Here, if either one is smaller, in step S923 or S924, the smaller addition result is left for the next comparison, and the larger one is excluded from the comparison target. If the two addition results are equal, step S9
At 22, the D of the above circuit system stage that is the target of each addition result
The magnitude of the SV value is compared. Then, if either one is smaller, in step S923 or S924, the addition result of the smaller DSV value is left for the next comparison, and the larger one is excluded from the comparison target. If these two DSV values are equal, the number of stages is smaller (in FIG. 13, the number of stages of the circuit system of the T0 addition conversion circuit is the smallest, and the number of stages of the circuit system of the T15 addition conversion circuit is the smallest). The result of addition of (large) is left for the next comparison, and the larger one is excluded from the comparison target.

In this way, the 16 addition results from Calc (0) to Calc (15) are narrowed down to 8.

Thereafter, in step S903, the addition result of 8 pieces is narrowed down to 4 pieces by the same processing as described above. The magnitude comparison of the addition results in step S903 is
Of the eight addition results that have been narrowed down, two from the smallest addition stage number are compared as a set. Similar to the above, the comparison process follows the process flow of FIG.

In the same manner, the addition result narrowed down to four is narrowed down to two in step S904, and further narrowed down to one in step S905. Then, the finally remaining added value Calc (i)
The initial value Ti of the circuit stage corresponding to is selected as the most preferable initial value.

Thereafter, in step S906, the DSV value, the peak value, the 0/1 run length value and the 1T run length value of the selected initial value stage are measured by the 16 stage DSV value measuring circuit 3 and the peak value measurement. The circuit 4 and the 0/1 run length measuring circuit 5 and the 1T run length measuring circuit 6 are set as initials, respectively.

According to the above embodiment, all the elements are comprehensively evaluated and the optimum initial value is selected by weighting. Therefore, as described above, the peak value and the DSV value are selected. As a result, it becomes possible to select a more preferable initial value as compared with the case of setting the priority order.

The processing flow according to the above embodiment corresponds to the block diagram of FIG. 13, but should correspond to the block diagrams of FIGS. 9, 11, 16, 18, and 20. You can also That is, in the block diagrams shown in these figures, although the comparison elements are different from those in the case of FIG. 13, if the weighting is set statistically for each element, the same processing as above is performed.
You will be able to select the optimal initial value. For example, FIG.
In the above, the comparison elements are the DSV value, the peak value, the 0/1 run length, the 1T run length value and the 1T number value, but in such a case, other than the peak value, the 0/1 run length and the 1T run length value, The 1T number value may also be weighted, and the weighted values may be multiplied by the weighted values and then added to calculate the added value Calc (i), as in the above.

However, the 1T number value may be considerably larger than the other elements, and the numerical range is larger than the other elements. Therefore, even if this is suppressed by the weighting value, it may have a great influence on the evaluation processing, and a result may occur in which the selection accuracy of the optimum initial value is slightly reduced. Therefore, the 1T number value may be filtered in advance so as to match the range with other evaluation elements, and then the added value Calc (i) may be calculated.

25 and 26 show the processing when the 1T number value is included as the comparison element. The flowchart of FIG. 25 corresponds to the flowchart of FIG. Figure 25
In the addition process of step S911, 1
A value f (1Tn) obtained by filtering the number value of T
um (i)) is the addition target. Step S90
The processing of 2 to S905 follows the processing of FIG. 24 as above. Then, when the optimum initial value is selected in step S905, in step S916, the DSV value, the peak value, the 0/1 run length, the 1T run length value, and the 1T number value with respect to the initial value are set to the DSV value measurement circuit 3,
The peak value measuring circuit 4, the 0/1 run length measuring circuit 5, the 1T run length measuring circuit 6 and the 1T number measuring circuit 9 are set as initials, respectively.

FIG. 26 is a flowchart of the filtering process for 1T pieces. When the number of 1T exceeds 150, the number of IT is used as it is without performing any filtering process. When the number of 1T exceeds 150, the element values such as the peak value and the DSV value are usually large.
It is better to exclude such an initial value from the selection candidates. Therefore, the value is used as it is without filtering the 1T number, and the initial value is excluded by the flow of FIG.

When the 1T number is less than 150 and is 130 or more, the value obtained by subtracting 50 from the number value is added target f (1
Tnum (i)). Similarly, when the number of 1T is less than 130 and 110 or more, a value obtained by subtracting 45 from the number value is set as the addition target f (1Tnum (i)). Similarly, the addition target f (1Tnum (i)) is calculated by subtracting each predetermined value from the 1T number value according to whether or not the 1T number exceeds a predetermined set value.

The numerical values shown in FIG. 26 can be changed appropriately by statistical processing.

Although the selection process of the optimum initial value by setting the weighting value has been described above, other selection process may be used. For example, in the above, the DSV value is excluded from the targets of addition (step S901 in FIG. 23), and the magnitude of the DSV value is compared in step S922 of the comparison process in FIG. It can also be set and added. In such a case, FIG.
The step S922 of 4 may be omitted, and the process may shift from the step S921 to the step S923, or the step S922 may be left and the DSV values may be compared again when the addition results are equal. good.

In addition, when the DSV value is included in the addition target, the magnitude comparison may be performed using another comparison element instead of using the DSV value in step S922 of FIG.

The embodiments of the present invention can be appropriately modified in various ways within the scope of the technical idea of the present invention.

[0147]

As described above, according to the present invention, when the data conversion is performed by adding the initial value to suppress both the peak value fluctuation of the DC fluctuation and the DSV, the 0/1 run length and the 1T run length are further added. Since the lengthening and the number of 1T can be suppressed together, the peak value fluctuation of the DC fluctuation and the DSV can be suppressed, as well as the redundancy of the DC component and the adverse effect on the Viterbi decoding can be further suppressed. Can be realized.

[Brief description of drawings]

FIG. 1 is a diagram showing a structure of a magneto-optical disk according to an embodiment.

FIG. 2 is a diagram showing a structure of a magneto-optical disk according to an embodiment.

FIG. 3 is a block diagram of a recording system according to an embodiment.

FIG. 4 is a block diagram of a reproduction system according to an embodiment.

FIG. 5 is a block diagram of a modulation circuit according to an embodiment.

FIG. 6 is a block diagram of a demodulation circuit according to an embodiment.

FIG. 7 is a diagram showing data conversion of the modulation circuit according to the embodiment.

FIG. 8 is a diagram showing data conversion of the demodulation circuit according to the embodiment.

FIG. 9 is a diagram showing a configuration example of an adaptive modulation circuit according to an embodiment.

FIG. 10 is an operation flowchart of the adaptive modulation circuit according to the embodiment.

FIG. 11 is a diagram showing another configuration example of the adaptive modulation circuit according to the embodiment.

FIG. 12 is an operation flowchart of the adaptive modulation circuit according to the embodiment.

FIG. 13 is a diagram showing still another configuration example of the adaptive modulation circuit according to the embodiment.

FIG. 14 is an operation flowchart of the adaptive modulation circuit according to the embodiment.

FIG. 15 is an operation flowchart of another adaptive modulation circuit according to the embodiment.

FIG. 16 is a diagram showing still another configuration example of the adaptive modulation circuit according to the embodiment.

FIG. 17 is an operation flowchart of the adaptive modulation circuit according to the embodiment.

FIG. 18 is a diagram showing still another configuration example of the adaptive modulation circuit according to the embodiment.

FIG. 19 is an operation flowchart of the adaptive modulation circuit according to the embodiment.

FIG. 20 is a diagram showing still another configuration example of the adaptive modulation circuit according to the embodiment.

FIG. 21 is an operation flowchart of the adaptive modulation circuit according to the embodiment.

FIG. 22 is an operation flowchart of another adaptive modulation circuit according to the embodiment.

FIG. 23 is still another operation flowchart of the adaptive modulation circuit according to the embodiment.

FIG. 24 is a processing flowchart of a magnitude comparison processing step in the flowchart.

FIG. 25 is a flowchart of yet another operation of the adaptive modulation circuit according to the embodiment.

FIG. 26 is a processing flowchart of a filter processing step in the flowchart.

[Explanation of symbols]

1 T0-15 additional conversion circuit 2 Recording data string conversion circuit 3 DSV value measurement circuit 4 Peak value measurement circuit 50/1 run length measurement circuit 6 1T run length measurement circuit 7 selection circuit 8 Tj additional conversion circuit 9 1T number measuring circuit

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Claims (66)

[Claims] 1. An information recording apparatus for modulating block data and then recording the same on a medium, wherein the modulating means for applying the modulation adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
Peak value measuring means for measuring the peak value of DC fluctuation when recording the converted data generated by the additional converting means on the medium, and measuring the DSV value when recording the converted data on the medium. DSV value measuring means, 0/1 run length measuring means for measuring the maximum value of the run length of 0 or 1 when recording the converted data on the medium, and the additional conversion for plural kinds of the initial data. The peak value, the DSV value, and the 0/1 run length value measured on the plurality of types of converted data generated by the means are compared with each other, and the initial data that suppresses these values are selected as the initial data. An information recording apparatus comprising: a selection unit. 2. The selecting means according to claim 1, wherein the selecting means prioritizes the plurality of types of converted data in an order in which the peak value and the DSV value are suppressed, and the conversion is performed in descending order of priority. An information recording apparatus, characterized in that the 0/1 run length value of the post data is compared with a set value, and the initial data of the converted data in which the 0/1 run length value first falls below the set value is selected. 3. The method according to claim 2, wherein when there is no converted data whose 0/1 run length value is first lower than the set value, the initial value of the converted data having the highest priority is selected. Characteristic information recording device. 4. An information recording apparatus for modulating block data and then recording the modulated data on a medium, wherein the modulating means for modulating adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
Peak value measuring means for measuring the peak value of DC fluctuation when recording the converted data generated by the additional converting means on the medium, and measuring the DSV value when recording the converted data on the medium. DSV value measuring means, 1T run-length measuring means for measuring the maximum value of the number of 1T repetitions when the converted data is recorded on the medium, and the additional converting means for a plurality of types of the initial data. And a selecting means for comparing the peak value, the DSV value, and the 1T run length value measured for a plurality of types of converted data, and selecting the initial data such that these values are suppressed as the initial data. An information recording device characterized by. 5. The selecting device according to claim 4, wherein the selecting means prioritizes the plurality of types of converted data in the order in which the peak value and the DSV value are suppressed, and the conversion is performed in descending order of priority. An information recording apparatus, characterized in that the 1T run length value of post data is compared with a set value, and the initial data of the converted data whose 1T run length value is first lower than the set value is selected. 6. The initial value of the post-conversion data having the highest priority is selected when no post-conversion data having a 1T run-length value first lower than the set value is present. Information recording device. 7. An information recording device for modulating block data and then recording the same on a medium, wherein the modulating means for applying the modulation adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
Peak value measuring means for measuring the peak value of DC fluctuation when recording the converted data generated by the additional converting means on the medium, and measuring the DSV value when recording the converted data on the medium. DSV value measuring means, 0/1 run length measuring means for measuring the maximum value of 0 or 1 run length when recording the converted data on the medium, and recording the converted data on the medium 1T run length measuring means for measuring the maximum value of the number of 1T repetitions, and the peak value, DSV value, measured for a plurality of types of converted data generated by the additional converting means with respect to a plurality of types of the initial data, A selector for comparing the 0/1 run length value and the 1T run length value, and selecting the initial data that suppresses both of these values as the initial data. Information recording apparatus characterized by having and. 8. The selecting means according to claim 7, wherein the selecting means prioritizes the plurality of types of converted data in the order in which the peak value and the DSV value are suppressed, and the conversion is performed in descending order of priority. The 0/1 run length value and the set value of the post data are compared, and the 1T run length value and the set value are compared, and both of the 0/1 run length value and the 1T run length value first set the respective set values. An information recording device, characterized in that it selects initial data of converted data that is lower than the above. 9. The conversion method with the highest priority according to claim 8, when there is no converted data in which both of the 0/1 run length value and the 1T run length value first fall below the respective set values. An information recording device characterized by selecting an initial value of post data. 10. The method according to claim 8, wherein there is no converted data in which both of the 0/1 run length value and the 1T run length value first fall below the respective set values.
An information recording apparatus, characterized in that either one of the 0/1 run length value and the 1T run length value is first selected to be an initial value of the converted data which is lower than the set value. 11. An information recording apparatus for modulating block data and then recording the same on a medium, wherein the modulating means for modulating adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and block data, and 0 or 1 for recording the converted data generated by the additional conversion means on the medium.
Of 0/1 run length measuring means for measuring the maximum value of the run lengths, and 1T run length measuring means for measuring the maximum value of the number of 1T repetitions when the converted data is recorded on the medium, The 0/1 run length value and 1T measured with respect to the plurality of types of converted data generated by the additional conversion means with respect to the initial data
An information recording apparatus, comprising: a selection unit that compares the run-length values and selects, as initial data, initial data that suppresses these values together. 12. An information recording apparatus for modulating block data and then recording the same on a medium, wherein the modulating means for applying the modulation adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
0/1 run length measuring means for measuring the maximum value of the run length of 0 or 1 when recording the converted data generated by the additional converting means on the medium, and the adding to the plural kinds of the initial data. 0 / measured on a plurality of types of post-conversion data generated by the conversion means
An information recording apparatus comprising: a selection unit that compares one run length value and selects, as initial data, initial data that minimizes this value. 13. An information recording device for modulating block data and then recording the same on a medium, wherein the modulating means for applying the modulation adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
1T run length measuring means for measuring the maximum number of 1T repetitions when recording the converted data generated by the additional converting means on a medium, and the additional converting means for generating a plurality of types of the initial data Information recording apparatus, comprising: a selection unit that compares the 1T run-length values measured for the converted plural types of converted data and selects the initial data that minimizes the value as the initial data. . 14. Additional conversion means for adding at least 2 bits or more of initial data to the block data, and then performing predetermined data conversion by the initial data and the block data, and post-conversion data generated by the additional conversion means. A peak value measuring means for measuring the peak value of the DC fluctuation when recording the data on the medium, a DSV value measuring means for measuring the DSV value when recording the converted data on the medium, and the converted data. 0/1 run length measuring means for measuring the maximum value of 0 or 1 run length when recording on a medium, and a plurality of types of converted data generated by the additional converting means for a plurality of types of the initial data Peak value, DSV value and 0/1
A modulation circuit, comprising: a selection unit that compares the run-length values and selects initial data such that these values are suppressed together as initial data. 15. The selecting means according to claim 14, wherein the selecting means prioritizes the plurality of types of converted data in the order in which the peak value and the DSV value are suppressed, and the conversion is performed in descending order of priority. A modulation circuit, wherein the 0/1 run-length value of post-data is compared with a set value, and the initial data of the converted data whose 0/1 run-length value first falls below the set value is selected. 16. The method according to claim 15, wherein when there is no converted data whose 0/1 run length value is first lower than the set value, the initial value of the converted data having the highest priority is selected. Characteristic modulation circuit. 17. Addition conversion means for adding at least 2 bits or more of initial data to block data, and then performing predetermined data conversion by the initial data and block data, and post-conversion data generated by the addition conversion means. A peak value measuring means for measuring the peak value of the DC fluctuation when recording the data on the medium, a DSV value measuring means for measuring the DSV value when recording the converted data on the medium, and the converted data. 1T run length measuring means for measuring the maximum value of the number of 1T repetitions when recording on a medium, and a plurality of kinds of converted data generated by the additional converting means for a plurality of kinds of the initial data are measured. The peak value, DSV value, and 1T run length value are compared, and the initial data that suppresses these values together A modulation circuit having a selecting means for selecting the period data. 18. The selecting means according to claim 17, wherein the selecting means prioritizes the plurality of types of converted data in an order in which the peak value and the DSV value are suppressed, and the conversion is performed in descending order of priority. A modulation circuit, wherein the 1T run-length value of the post-data is compared with a set value, and the initial data of the converted data whose 1T run-length value first falls below the set value is selected. 19. The method according to claim 18, wherein when there is no converted data whose 1T run-length value is first lower than the set value, the initial value of the converted data having the highest priority is selected. Modulation circuit to do. 20. Additional conversion means for adding at least 2 bits or more of initial data to the block data and then performing predetermined data conversion by the initial data and the block data, and post-conversion data generated by the additional conversion means. A peak value measuring means for measuring the peak value of the DC fluctuation when recording the data on the medium, a DSV value measuring means for measuring the DSV value when recording the converted data on the medium, and the converted data. 0/1 run length measuring means for measuring the maximum value of the run length of 0 or 1 when recording on the medium, and measuring the maximum value of the number of 1T repetitions when recording the converted data on the medium. 1T run length measuring means and a plurality of types of converted data generated by the additional converting means with respect to a plurality of types of the initial data were measured. The peak value, the DSV value, the 0/1 run length value, and the 1T run length value, respectively, and selecting means for selecting as initial data initial data such that these values are suppressed together. Modulation circuit to do. 21. The selecting means according to claim 20, wherein the selecting means prioritizes the plurality of types of converted data in the order in which the peak value and the DSV value are suppressed, and the conversion is performed in descending order of priority. The 0/1 run length value and the set value of the post data and the 1T run length value and the set value are compared, and the 0/1 run length value and 1T are compared.
A modulation circuit, wherein both of the run length values are initially lower than the respective set values, and the initial data of the converted data is selected. 22. The conversion with the highest priority according to claim 21, when there is no converted data in which both the 0/1 run length value and the 1T run length value are first lower than the respective set values. A modulation circuit characterized by selecting an initial value of post-data. 23. In claim 21, if there is no post-conversion data in which both the 0/1 run length value and the 1T run length value first fall below the respective set values, the 0/1 run is present. A modulation circuit, wherein one of a length value and a 1T run length value is first selected to be an initial value of converted data which is lower than the set value. 24. Additional conversion means for adding at least 2 bits or more of initial data to the block data, and then performing predetermined data conversion by the initial data and the block data; and post-conversion data generated by the additional conversion means. 0/1 run length measuring means for measuring the maximum value of the run length of 0 or 1 when recording the data on the medium, and the maximum value of the number of 1T repetitions when recording the converted data on the medium. 1T run length measuring means for comparing the 0/1 run length value and the 1T run length value measured for a plurality of types of converted data generated by the additional conversion means with respect to a plurality of types of the initial data, respectively, It has a selecting means for selecting as initial data initial data such that these values are both suppressed. And a modulation circuit. 25. Additional conversion means for adding at least 2 bits or more of initial data to the block data and then performing predetermined data conversion by the initial data and the block data, and post-conversion data generated by the additional conversion means. 0/1 run length measuring means for measuring the maximum value of the run length of 0 or 1 when recording the data on the medium, and a plurality of types of converted data generated by the additional converting means for the plurality of types of the initial data. A modulation circuit comprising: a selection unit that compares the 0/1 run length values measured for data and selects, as initial data, initial data that minimizes this value. 26. Additional conversion means for adding at least 2 bits or more of initial data to the block data, and then performing predetermined data conversion by the initial data and the block data, and post-conversion data generated by the additional conversion means. 1T run length measuring means for measuring the maximum value of the number of 1T repetitions when recording on a medium, and a plurality of types of converted data generated by the additional converting means with respect to a plurality of types of the initial data were measured. A modulation circuit comprising: a selection unit that compares the 1T run length values and selects, as initial data, initial data that minimizes this value. 27. In an information recording apparatus for modulating block data and recording the same on a medium, the modulating means for modulating adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
Peak value measuring means for measuring the peak value of DC fluctuation when recording the converted data generated by the additional converting means on the medium, and measuring the DSV value when recording the converted data on the medium. DSV value measuring means, 1T number measuring means for measuring the number of 1T when recording the converted data on a medium, and plural kinds of conversions generated by the additional conversion means for plural kinds of the initial data. The peak value, DSV value and 1 measured for the post data
An information recording apparatus comprising: a selection unit that compares the T number values with each other and selects, as initial data, initial data such that these values are suppressed together. 28. The selecting means according to claim 27, wherein the selecting means prioritizes the plurality of types of converted data in an order in which the peak value and the DSV value are suppressed, and the conversion is performed in descending order of priority. An information recording apparatus, characterized in that the 1T number value of post data is compared with a set value, and the initial data of the converted data in which the 1T number value first falls below the set value is selected. 29. An initial value of the converted data having the highest priority is selected when there is no converted data whose 1T run-length value is first lower than the set value. Information recording device. 30. In an information recording device for modulating block data and recording the same on a medium, the modulating means for modulating adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
Peak value measuring means for measuring the peak value of DC fluctuation when recording the converted data generated by the additional converting means on the medium, and measuring the DSV value when recording the converted data on the medium. DSV value measuring means, 0/1 run length measuring means for measuring the maximum value of 0 or 1 run length when recording the converted data on the medium, and recording the converted data on the medium 1T number measuring means for measuring the number of 1T, and the peak value, DS, measured on a plurality of types of converted data generated by the additional conversion means with respect to a plurality of types of the initial data.
An information recording apparatus comprising: a V value, a 0/1 run length value, and a 1T number value, respectively, and selecting means for selecting as initial data initial data such that these values are both suppressed. 31. The selecting means according to claim 30, wherein the selecting means prioritizes the plurality of types of converted data in the order in which the peak value and the DSV value are suppressed, and the conversion is performed in descending order of priority. The 0/1 run length value and the set value of the post data are compared, and the 1T number value and the set value are compared, and both of the 0/1 run length value and the 1T number value are first below the respective set values. An information recording device characterized by selecting initial data of converted data. 32. In claim 31, if there is no post-conversion data in which both the 0/1 run length value and the 1T number value are first lower than the respective set values, the post-conversion data having the highest priority is given. An information recording apparatus characterized by selecting an initial value of data. 33. The converted 0/1 run length according to claim 31, wherein both of the 0/1 run length value and the 1T number value first fall below the respective set values, if there is no converted data. An information recording apparatus, wherein either one of a value and a 1T number value is first selected to be an initial value of converted data which is lower than the set value. 34. In an information recording device for modulating block data and recording the same on a medium, the modulating means for modulating adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
Peak value measuring means for measuring the peak value of DC fluctuation when recording the converted data generated by the additional converting means on the medium, and measuring the DSV value when recording the converted data on the medium. DSV value measuring means, 0/1 run length measuring means for measuring the maximum value of 0 or 1 run length when recording the converted data on the medium, and recording the converted data on the medium 1T run length measuring means for measuring the maximum number of 1T repetitions, 1T number measuring means for measuring the number of 1T when the converted data is recorded on the medium, and a plurality of types of the initial data. The peak value measured for a plurality of types of converted data generated by the additional conversion means, D
SV value, 0/1 run length value, 1T run length value, and 1T number value are respectively compared, and there is provided a selection means for selecting initial data as the initial data such that these values are suppressed together. Information recording device. 35. The selecting means according to claim 34, wherein the selecting means prioritizes the plurality of types of converted data in an order in which the peak value and the DSV value are suppressed, and the conversion is performed in descending order of priority. Comparing the 0/1 run length value and the setting value of the post data, comparing the 1T run length value and the setting value, and comparing the 1T number value and the setting value,
An information recording apparatus, wherein the 0/1 run length value, the 1T run length value, and the 1T number value all select initial data of the converted data that is first lower than the respective set values. 36. The priority order according to claim 35, when there is no post-conversion data in which all of the 0/1 run length value, the 1T run length value and the 1T number value all first fall below the respective set values. An information recording device, characterized in that the initial value of the converted data having the highest value is selected. 37. The converted data according to claim 35, wherein all of the 0/1 run length value, the 1T run length value, and the 1T number value all first fall below the respective set values, and there is no converted data. 0/1 run length value,
An information recording apparatus, wherein any one of a 1T run length value and a 1T number value first selects an initial value of converted data having a value lower than the set value. 38. In an information recording device for modulating block data and recording the same on a medium, the modulating means for modulating adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
0/1 run length measuring means for measuring the maximum value of the run length of 0 or 1 when the converted data generated by the additional converting means is recorded on the medium, and the converted data is recorded on the medium. 1T number measuring means for measuring the number value of 1T at the time, and the 0/1 run length value and 1T pieces measured for a plurality of types of converted data generated by the additional conversion means with respect to a plurality of types of the initial data. An information recording apparatus, comprising: a selection unit that compares numerical values and selects initial data such that these values are both suppressed as initial data. 39. In an information recording device for modulating block data and recording it on a medium, the modulating means for modulating adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
1T number measuring means for measuring the number of 1T when the converted data generated by the additional conversion means is recorded on the medium, and a plurality of types of the initial data of a plurality of types generated by the additional conversion means. An information recording apparatus comprising: a selection unit that compares the 1T number values measured for the converted data and selects, as the initial data, the initial data that minimizes this value. 40. In an information recording device for modulating block data and recording the same on a medium, the modulating means for modulating adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
Selecting means for selecting the initial data, wherein the selecting means records the converted data generated by the additional converting means on a medium, the peak value of the DC fluctuation, and the converted data on the medium. And a DSV value when recording on the medium, and a run length value of 0 or 1 when recording the converted data on the medium and / or 1T when recording the converted data on the medium. An information recording apparatus comprising: selecting initial data that suppresses a measured value as the initial data. 41. In an information recording apparatus for modulating block data and recording the same on a medium, the modulating means for modulating adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
Selecting means for selecting the initial data, wherein the selecting means is a run length value of 0 or 1 when recording the converted data generated by the additional converting means on a medium and / or the converted data. When recording on a medium
An information recording apparatus, wherein initial data that suppresses a measured value of T is selected as the initial data. 42. In an information recording device for modulating block data and recording the same on a medium, the modulating means for modulating adds at least 2 bits or more of initial data to the block data. After that, additional conversion means for performing predetermined data conversion by the initial data and the block data,
Selecting means for selecting the initial data, wherein the selecting means sets the initial data for suppressing the 1T measurement value when the converted data generated by the additional converting means is recorded on the medium. An information recording device characterized by being selected as data. 43. Additional conversion means for adding at least 2 bits or more of initial data to the block data, and then performing predetermined data conversion by the initial data and the block data, and post-conversion data generated by the additional conversion means. A peak value measuring means for measuring the peak value of the DC fluctuation when recording the data on the medium, a DSV value measuring means for measuring the DSV value when recording the converted data on the medium, and the converted data. 1T number measuring means for measuring the number of 1T when recording on a medium, the peak value measured for a plurality of types of converted data generated by the additional conversion means with respect to a plurality of types of the initial data, DS
A modulation circuit comprising: a selection unit that compares the V value and the 1T number value with each other and selects, as initial data, initial data such that these values are both suppressed. 44. The selecting means according to claim 43, wherein the selecting means prioritizes the plurality of types of converted data in an order in which the peak value and the DSV value are suppressed, and the conversion is performed in descending order of priority. A modulation circuit, wherein the 1T number value of post-data is compared with a set value, and the initial data of the converted data whose 1T number value first falls below the set value is selected. 45. The converted data having the highest priority is selected when there is no converted data whose 1T run-length value is first lower than the set value. Modulation circuit to do. 46. Additional conversion means for adding at least 2 bits or more of initial data to the block data and then performing predetermined data conversion by the initial data and the block data, and post-conversion data generated by the additional conversion means. A peak value measuring means for measuring the peak value of the DC fluctuation when recording the data on the medium, a DSV value measuring means for measuring the DSV value when recording the converted data on the medium, and the converted data. 0/1 run length measuring means for measuring the maximum value of the run length of 0 or 1 when recording on the medium, and 1T number measuring means for measuring the number of 1T when recording the converted data on the medium And the peak value, DSV value, 0 measured on the plurality of types of converted data generated by the additional conversion means with respect to the plurality of types of the initial data. And a 1T run length value and a 1T number value, respectively, and selecting means for selecting as initial data initial data such that these values are both suppressed. 47. The selecting means according to claim 46, wherein the selecting means prioritizes the plurality of types of converted data in an order in which the peak value and the DSV value are suppressed, and the conversion is performed in descending order of priority. The 0/1 run length value and the set value of the post data are compared, and the 1T number value and the set value are compared, and both of the 0/1 run length value and the 1T number value are first below the respective set values. A modulation circuit for selecting initial data of converted data. 48. In claim 47, when there is no post-conversion data in which both the 0/1 run length value and the 1T number value first fall below the respective setting values, the post-conversion data having the highest priority is given. A modulation circuit characterized by selecting an initial value of data. 49. The 0/1 run length according to claim 47, when there is no converted data in which both the 0/1 run length value and the 1T number value are first lower than the respective set values. A modulation circuit, wherein one of a value and a 1T number value is first selected to be an initial value of the converted data which is lower than the set value. 50. Additional conversion means for adding at least 2 bits or more of initial data to the block data, and then performing predetermined data conversion by the initial data and the block data; and post-conversion data generated by the additional conversion means. A peak value measuring means for measuring the peak value of the DC fluctuation when recording the data on the medium, a DSV value measuring means for measuring the DSV value when recording the converted data on the medium, and the converted data. 0/1 run length measuring means for measuring the maximum value of the run length of 0 or 1 when recording on the medium, and measuring the maximum value of the number of 1T repetitions when recording the converted data on the medium. 1T run length measuring means, 1T number measuring means for measuring the number of 1T when recording the converted data on a medium, and a plurality of types of the initial data. On the other hand, the peak value, the DSV value, the 0/1 run length value, the 1T run length value, and the 1T number value measured on the plurality of types of converted data generated by the additional conversion means are compared, and these values are A modulation circuit, comprising: selecting means for selecting, as initial data, initial data that is suppressed. 51. The selecting means according to claim 50, wherein the selecting means prioritizes the plurality of types of converted data in an order in which the peak value and the DSV value are suppressed, and the conversion is performed in descending order of priority. Comparing the 0/1 run length value and the setting value of the post data, comparing the 1T run length value and the setting value, and comparing the 1T number value and the setting value,
A modulation circuit, wherein the 0/1 run length value, the 1T run length value, and the 1T number value are all selected to be initial data of the converted data that first falls below the respective set values. 52. The priority order according to claim 51, when there is no converted data in which all of the 0/1 run length value, the 1T run length value and the 1T number value are first lower than the respective set values. The modulation circuit is characterized by selecting the initial value of the converted data which is the highest. 53. The converted data according to claim 51, wherein all of the 0/1 run length value, the 1T run length value, and the 1T number value all first fall below the respective set values, and there is no converted data. 0/1 run length value,
A modulation circuit, wherein any one of a 1T run-length value and a 1T number value first selects an initial value of converted data which is lower than the set value. 54. Additional conversion means for adding at least 2 bits or more of initial data to the block data, and then performing predetermined data conversion by the initial data and the block data, and post-conversion data generated by the additional conversion means. 0/1 run length measuring means for measuring the maximum value of the run length of 0 or 1 when recording the data on the medium, and the 1T number for measuring the number value of 1T when recording the converted data on the medium The measuring means and the 0/1 run-length value and the 1T number value measured on the plurality of types of converted data generated by the additional converting means with respect to the plurality of types of the initial data are respectively compared, and these values are the same. A modulation circuit, comprising: selecting means for selecting, as initial data, initial data that is suppressed. 55. Additional conversion means for adding at least 2 bits or more of initial data to the block data and then performing predetermined data conversion by the initial data and the block data, and post-conversion data generated by the additional conversion means. 1T number measuring means for measuring the number of 1T when recording on a medium, and the 1T number value measured for a plurality of kinds of converted data generated by the additional converting means with respect to a plurality of kinds of the initial data, And a selecting means for comparing and selecting as initial data initial data such that this value is most suppressed. 56. Addition conversion means for adding at least 2 bits or more of initial data to the block data, and then performing predetermined data conversion by the initial data and the block data, and selection means for selecting the initial data. The selecting means suppresses the peak value of the DC fluctuation when recording the converted data generated by the additional converting means on the medium and the DSV value when recording the converted data on the medium. And the initial data for suppressing the run length value of 0 or 1 when recording the converted data on the medium and / or the 1T measurement value when recording the converted data on the medium. A modulation circuit characterized in that it is selected as initial data. 57. Addition conversion means for adding at least 2 bits or more of initial data to the block data and then performing predetermined data conversion by the initial data and the block data, and a selection means for selecting the initial data. The selecting means is a run length value of 0 or 1 when recording the converted data generated by the additional converting means on the medium and / or 1 when recording the converted data on the medium.
A modulation circuit, wherein initial data that suppresses a measured value of T is selected as the initial data. 58. Additional conversion means for adding at least 2 bits or more of initial data to the block data and then performing predetermined data conversion by the initial data and the block data, and a selection means for selecting the initial data. The selection means selects, as the initial data, initial data that suppresses a measured value of 1T when the converted data generated by the additional conversion means is recorded on a medium. Information recording device. 59. Claims 1, 4, 7, 27, 30, 34.
40. The information recording device according to 40, wherein the selecting means selects the peak value, the DSV value, the 0/1 run length value, the 1T run length value, and the 1T number value elements measured for the converted data, An information recording device characterized by setting predetermined weights for the combinations defined in the claims and comparing each element after setting the weights to select the optimum initial data. . 60. The information recording device according to claim 59, wherein the selection unit multiplies the value of each element by a predetermined weighting value, and then adds the multiplication values so that the added value becomes minimum. An information recording device characterized by selecting initial data. 61. The information recording apparatus according to claim 60, wherein the selecting means multiplies the values of the respective elements excluding the DSV value by a weighting value and then adds these multiplication values to determine the magnitude of the addition value. In comparison, when the added values are equal, the initial data having the smaller DSV value is selected. 62. The information recording device according to any one of claims 59 to 61, wherein the 1T number value is subjected to predetermined filtering to reduce the value, and then this value is compared with the values of other elements. An information recording device characterized by: 63. Claims 14, 17, 20, 43, 4
In the modulation circuits described in 6, 50 and 56, the selecting unit selects each element of the peak value, the DSV value, the 0/1 run length value, the 1T run length value, and the 1T number value measured for the converted data. When comparing the combinations defined in each of the claims, a predetermined weighting is set for these, and each element after the weighting is set is compared, and the optimum initial data is selected. circuit. 64. The change circuit according to claim 63, wherein the selection unit multiplies the value of each element by a predetermined weighting value and then adds the multiplication values to each other to obtain an initial value that minimizes the addition value. A change circuit characterized by selecting data. 65. The change circuit according to claim 64, wherein the selecting means multiplies the value of each element excluding the DSV value by a weighting value, adds the multiplication values, and compares the addition values. In doing so, when the added values are equal, the initial data having the smaller DSV value is selected. 66. The modification circuit according to claim 63, wherein the 1T number value is subjected to predetermined filtering to reduce the value, and then this value is compared with the values of other elements. , A modified circuit characterized by the following.