JP2004127417A - Recording medium, its recording/reproducing device, and its recording/reproducing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide format constitution which raises the driving reliability of a high density recording optical disk by a driving device. <P>SOLUTION: Secondary data are recorded on an optical disk 100 by using the jitter margin of the clock window of main data. In a first section, main data are recorded on the disk by a reference clock which positioned at a reference phase disposition. In a second section following the first section, main data are recorded on the disk by a reference clock whose phase is shifted by a prescribed amount from the reference phase disposition. In a third section following the second section, main data are recorded on the disk by the reference clock which is positioned at the reference phase disposition. For example, a section positioned at the reference phase disposition is made to correspond to "0" of the secondary data and a section having a reference clock whose phase is shifted is made to correspond to "1" of the secondary data. As a result, management information, etc. can be recorded simultaneously with main data on the optical disk as secondary data. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a recording medium, a recording and / or reproducing apparatus thereof, and a recording and / or reproducing method thereof.
[0002]
[Prior art]
Recently, recording media, such as DVDs, DVD-RAMs, CDs, CD-Rs, and optical disks such as MOs and MDs, are required to have higher and higher densities. In accordance with the demand, a technology enabling higher density recording on a recording medium has been studied and realized. In order to achieve a higher density of the recording medium, it is necessary not only to improve and improve the characteristics of the recording medium itself and the recording method, but also to make sure that the driving device for driving the recording medium has a driving condition suitable for the recording medium. Therefore, it is necessary to drive the recording medium.
[0003]
For example, in many CD-Rs, recording of information on the CD-R can be performed at double speed and quadruple speed. However, in a specific CD-R, only recording at a normal speed is possible, and when information is recorded at a double speed or a quadruple speed, the recorded information may not be accurately reproduced. Therefore, in order to appropriately drive the recording medium, detailed conditions for driving the recording medium must be set in the driving device.
[0004]
It is necessary to change these setting conditions for each recording medium to be inserted and driven, and set appropriate conditions. In order to reliably perform recording / reproducing of the optical disk and configure a highly reliable recording system, it is necessary to appropriately set the recording characteristics / recording / reproducing conditions of the optical disk in the driving device. If the recording and reproduction conditions cannot be set to appropriate ones, appropriate reproduction or recording cannot be performed.
[0005]
In view of the above, an environment in which recording and reproduction can be performed is required only as a format for high-density recording, as long as the drive device can appropriately set recording and reproduction conditions. As described above, the problem exists in the relationship between the recording medium and the driving device. For example, when the recording medium cannot perform high-density recording and reproduction, the information cannot be appropriately recorded even if the drive unit attempts to perform high-density recording on the medium.
[0006]
On the other hand, it is also important to protect information recorded on an optical disc. There is a demand for a function of preventing information from being easily read out and copied from a recording medium recorded at high density. In particular, since a large amount of information is recorded on a single recording medium, it is required to make it difficult to reproduce the information from the recording medium and create a recording medium on which the information is duplicated.
[0007]
For example, key information for reading information from the information recording medium and unique information for confirming compatibility between the information recording medium and the medium driving device are written in the information recording medium using a transparent latent image ink having a photoluminescence effect. It is known to form a latent image mark on the surface. As a result, the confidentiality of such information is high, information can be prevented from being read out by means other than a dedicated medium drive device, and duplication and spread of copyrighted works and secret information can be prevented (see Patent Document 1).
[0008]
One mode of copying illegal information by a third party is copying information as content recorded by a user. As a means for preventing duplication of user information, a technique using ID information as described above is known. However, once the ID information for confirming the suitability has been copied, the third party can repeat the information by continuing to use the information. Alternatively, when an authentication algorithm based on ID information is known to a third party, there is a problem that the ID information is duplicated and the information is thereby duplicated easily.
[0009]
Alternatively, it is important to prevent unauthorized duplication of information by a third party from duplication of information pre-recorded on a recording medium at the manufacturing stage, including management information, in addition to information as content recorded by a user. It is. For example, there is a problem that a so-called imitation of a rewritable recording medium is supplied to the market after being copied from a rewritable recording medium having no content as body information by a third party such as a manufacturer identification ID and management information. There is.
[0010]
[Patent Document 1]
JP-A-7-192385
[0011]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION The present invention has been made in view of the above prior art, and an object of the present invention is to provide a recording medium, a recording and / or reproducing apparatus thereof, and a recording thereof, which enable more secure driving of the recording medium. And / or a playback method.
[0012]
[Means for Solving the Problems]
A first aspect of the present invention is a recording medium on which main data is recorded based on a reference clock in a data recording area divided into a plurality of sections, wherein the main data is recorded in a reference phase arrangement of the reference clock. And a second section in which main data is recorded based on a reference clock in a different phase arrangement from the first section. According to the above configuration, for example, the subsidiary data can be recorded, and the management information of the main information can be recorded in parallel. For example, the subsidiary data can be information that assists the reproduction condition of the main information and the like, which facilitates management.
[0013]
It is preferable that the phase shift amount between the first section and the second section is in a predetermined range. Thereby, for example, it is possible to clarify the distinction between the naturally occurring jitter and the jitter intentionally generated in manufacturing.
The data recording area has a plurality of second sections, and each of the plurality of second sections has a phase shift amount delayed or advanced with respect to the reference phase arrangement. Can be.
Preferably, the phase shift amount is substantially 5 to 15% of the reference clock cycle. With this configuration, for example, it is possible to reproduce appropriate main data and subsidiary data.
Preferably, the phase shift amount is substantially 20% or less with respect to the reproduction reference clock window of the recording medium. With this configuration, for example, it is possible to reproduce appropriate main data and subsidiary data.
It is preferable that a minimum section of the second section is longer than a longest mark modulated by the reference clock. With this configuration, since interference does not occur in terms of spectrum, interference with main data can be suppressed.
It is preferable that subsidiary data is recorded by the first section and the second section. By recording the subsidiary data, the security of driving the recording medium can be improved.
[0014]
Another aspect of the present invention is a recording medium in which main data is recorded based on a reference clock in a data recording area divided into a plurality of sections. A first section in which data is recorded, and a second section in which main data is recorded with a phase shift within a range of 5 to 15% of the reference clock cycle from the reference phase arrangement. On the basis of the secondary data. By recording the subsidiary data by the above configuration, the security of driving the recording medium can be improved.
[0015]
Another aspect of the present invention is a recording medium in which main data is recorded based on a plurality of clocks in a data recording area having a plurality of divided sections. Has data recorded at a clock frequency assigned to the plurality of sections, and a clock frequency is assigned to each section of the plurality of sections according to preset frequency data, and the clock frequency differs in at least one track. Is the thing. With this configuration, the security of driving the recording medium can be improved.
[0016]
Another aspect of the present invention is a recording medium on which main data is recorded based on a plurality of clocks in a data recording area having a plurality of divided sections, wherein each section of the plurality of sections is predetermined. The data recording area includes data recorded at the first clock frequency, and a plurality of first sections having data recorded at the first clock frequency, and one section continuous with the first section. And a second section having data recorded at a second frequency different from the first clock frequency. With this configuration, the security of driving the recording medium can be improved.
[0017]
Another aspect of the present invention is a recording medium in which main data is recorded based on a plurality of clocks in a data recording area having a plurality of divided sections. And data recorded at the clock frequency assigned to each section, and the subsidiary data is recorded based on the clock frequency assigned to each section. By recording the subsidiary data by the above configuration, the security of driving the recording medium can be improved.
[0018]
In the minimum section of the plurality of sections, it is preferable to record the subsidiary data in units of a section longer than the longest mark modulated by the clock assigned to each section. With this configuration, since interference does not occur in terms of spectrum, interference with main data can be suppressed.
[0019]
Another aspect of the present invention is an apparatus that performs recording and / or reproduction of a recording medium, wherein the reading unit reads main data recorded on the recording medium, and the main data read based on the read main data. It has a detecting means for detecting phase data which is data relating to a phase, and a secondary data demodulating means for demodulating secondary data based on the phase data detected by the detecting means. By reproducing the subsidiary data by the above configuration, the security of driving the recording medium can be improved.
[0020]
The detecting means can detect a phase shift amount between the main data based on detection of a data reproduction position in a data clock window.
The detecting means can detect a phase shift amount between the main data based on a phase difference signal from a clock reproducing means for reproducing a clock based on the main data.
[0021]
Another aspect of the present invention is a method of recording and / or reproducing a recording medium, comprising: a reading step of reading main data recorded on a recording medium; and reading the main data based on the read main data. A detecting step of detecting phase data which is data relating to a phase; and a sub-data demodulating step of demodulating sub-data based on the phase data detected by the detecting means. By reproducing the subsidiary data by the above configuration, the security of driving the recording medium can be improved.
[0022]
Another aspect of the present invention is an apparatus for recording and / or reproducing data on and from a recording medium, comprising: reading means for reading main data recorded on the recording medium; and a clock for the main data based on the read main data. It has a detecting means for detecting a frequency, and a secondary data demodulating means for demodulating secondary data based on the frequency detected by the detecting means. By reproducing the subsidiary data by the above configuration, the security of driving the recording medium can be improved.
[0023]
Another aspect of the present invention is an apparatus for performing recording and / or reproduction on a recording medium to which different frequencies are assigned to a plurality of data storage sections, wherein a clock frequency corresponding to the plurality of data storage sections is set. A memory having frequency data for generating a clock frequency for the recording medium based on the frequency data stored in the memory; and a data storage section based on the generated clock frequency. Recording or reproduction of data to or from a computer. With the above configuration, the security of driving the recording medium can be improved.
[0024]
Another aspect of the present invention is a method for performing recording and / or reproduction on a recording medium in which different frequencies are assigned to a plurality of data storage sections, and sets a clock frequency corresponding to the plurality of data storage sections. Generating a clock frequency for the recording medium based on the frequency data for recording and reproducing or recording data in the data storage section based on the generated clock frequency. is there. With the above configuration, the security of driving the recording medium can be improved.
[0025]
Another embodiment of the present invention is a recording medium having main data recorded based on a reference clock and subsidiary data recorded by modulating the phase of the reference clock. By having the subsidiary data with the above configuration, the security of driving the recording medium is improved.
Another aspect of the present invention is an apparatus that performs recording and / or reproduction of a recording medium, wherein the clock generating means generates a clock used for recording main data on the recording medium, A recording unit that records data on a recording medium based on a clock; and a memory that records secondary data, wherein the clock generation unit changes a phase based on the secondary data recorded in the memory. To output a clock. By recording the subsidiary data according to the above configuration, the security of driving the recording medium can be improved.
[0026]
Another aspect of the present invention is an apparatus that performs recording and / or reproduction of a recording medium, wherein the clock generating means generates a clock used for recording main data on the recording medium, A recording unit that records main data on a recording medium based on the clock; and a memory that records secondary data, wherein the clock generation unit sets an output clock frequency based on the secondary data recorded in the memory. Change things. By recording the subsidiary data according to the above configuration, the security of driving the recording medium can be improved.
[0027]
Another aspect of the present invention is a method for recording and / or reproducing data on a recording medium, comprising the steps of: generating a clock used for recording main data on the recording medium; And recording the data on a recording medium, wherein the step of generating a clock generates the clock such that the phase of the output clock is shifted based on the subsidiary data recorded in the memory. . By recording the subsidiary data according to the above configuration, the security of driving the recording medium can be improved.
[0028]
Another aspect of the present invention is a method for recording and / or reproducing data on a recording medium, comprising the steps of: generating a clock used for recording main data on the recording medium; And recording the data on a recording medium, wherein the step of generating a clock generates the clock such that the output clock frequency changes based on the subsidiary data recorded in the memory. . By recording the subsidiary data according to the above configuration, the security of driving the recording medium can be improved.
[0029]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following description shows an example of the embodiment of the present invention, and the scope of the present invention is not limited only to the following description. The following description has been omitted or simplified in order to clearly explain the content of the present invention. Also, those skilled in the art can appropriately make changes, substitutions, and additions to the configurations described below within the scope of the present invention.
[0030]
Embodiment 1 FIG.
The optical disc of this embodiment records subsidiary data by phase-modulating the clock of the main data. In particular, the subsidiary data is recorded using the jitter margin of the clock window of the independent data. By recording the subsidiary data by the clock phase shift, the security of the optical disk can be improved. This embodiment is applicable to various recording media represented by optical disks such as DVD, DVD-RW, DVD-RAM, CD, CD-R, MO and MD.
[0031]
FIG. 1 shows a general configuration of a DVD-RAM as an example of a typical optical disc 100. An optical disc of a type such as a DVD-RAM that records data from the inner periphery side has an additional recording in which a lead-in area 101 including a control track is recorded on the inner periphery and user data as main body data is recorded outside the lead-in area 101. An area 102 is formed. Since the DVD-RAM is used from the inner circumference side, the lead-in area 104 is arranged on the inner circumference side. A disk to be recorded from the outer peripheral side has a lead-in area on the outer peripheral side. A magneto-optical disk such as an MO is not called a lead-in area, but has a control track area on both the inner circumference and the outer circumference.
[0032]
The control track records management information relating to the recording / reproducing operation of the recording medium, such as recording / reproducing / erasing conditions of the disc. The management information includes, for example, information used for driving the optical disc, such as TOC, manufacturer identification information of the optical disc, laser power, laser frequency, rotation speed, format information, and information on a modulation method. In addition, information used for driving the optical disc, such as information required for starting data reproduction or data recording on the optical disc, and information for accurate reproduction, such as a scramble key, can be included. The subsidiary data of this embodiment can include, for example, the management information described above. Secondary data can be recorded with a clock in a lead-in or additional recording area.
[0033]
FIG. 2 is a diagram showing a state in which the subsidiary data is recorded in the margin of the jitter of the reference clock in the present embodiment. In an optical disc on which a data string is continuously modulated and recorded, data to be recorded is recorded in synchronization with a reference clock. That is, the information to be recorded is added with an error correction code and control information (synchronization signal, address signal, control signal, etc.) necessary for recording, and if necessary, subjected to scramble processing to perform modulation for recording (1-7 or 2-7RLL, 8-16 conversion). The data string to be recorded is recorded in synchronization with the modulation signal using a reference clock.
[0034]
This reference clock plays an important role in reproducing data from a reproduced signal during reproduction. That is, discrimination of data reproduction is provided in a window partitioned by the reference clock. In general specifications of an optical disk, fluctuations in a clock window of a reproduction signal are defined as jitter. For a medium such as a DVD-ROM, for example, about 8% of the clock window is specified as a guide. That is, if the fluctuation is within this range, it is guaranteed that the reliability of data reproduction can be ensured in the reproduction process of the drive. Actually, it is defined with a margin for the window, and even if there is a jitter exceeding about 8%, there is little problem with reproduction data.
[0035]
In FIG. 2, reference numeral 201 denotes a reference clock used for recording / reproducing main data. Reference numeral 202 denotes a reference clock modulated so as to record subsidiary data. 202 has three sections. In the first section, the reference clock is in a reference phase arrangement. In the second section following the first section, the phase of the reference clock is shifted from the reference phase arrangement by a predetermined amount. The second section in FIG. 2 shows a state where the phase is advanced with respect to the reference phase arrangement. In the third section following the second section, the phase of the reference clock returns to the reference phase arrangement.
[0036]
For example, in the second section, subsidiary data of "1" is recorded, and in the first and third sections, subsidiary data of "0" is recorded. Thus, the phase shift in each section is controlled according to the value of the subsidiary data. The phase shift can be advanced or delayed with respect to the reference phase arrangement. Further, the relationship between the phase shift and the subsidiary data corresponding to the shift can be appropriately selected. For example, a case having a phase shift advanced by a predetermined amount can correspond to subsidiary data of "1", and a case having a phase shift delayed by a predetermined amount can correspond to subsidiary data of "0". A plurality of sections out of phase with respect to the reference phase arrangement are formed according to the data length of the subsidiary data.
[0037]
As shown in FIG. 2B, it is preferable that the phase of the reference clock in the second section is ahead of the reference phase arrangement by 5 to 15% of the reference clock cycle. In consideration of a proper operation of the driving device and a balance with a shift amount for recording the subsidiary data, the phase shift amount is preferably substantially 5 to 15% of the reference clock cycle. If it is 5% or less, there is a high possibility that the secondary data cannot be reproduced due to the problems of modulation sensitivity and detection. On the other hand, a jitter exceeding 15% may be a factor that hinders proper operation of the driving device. If the drive is designed so as to allow a jitter margin of up to 15%, it is possible to control the medium jitter amount up to 15%. Further, from the same viewpoint, the phase shift amount is preferably less than 20% with respect to the reproduction reference clock window. The section length of the section for modulating the phase of the reference clock can be changed depending on the modulation section.
[0038]
By shifting the reference clock phase for recording in a certain range, a window of the reproduced clock reproduced from the shifted point by the previous clock phase information generates instantaneous jitter by the shifted amount. Normally, the reproduced clock is generated by the PLL circuit from the reproduced signal, but the window does not return immediately by the time constant of the PLL circuit (phase synchronization is shifted). Therefore, at this time, in the PLL circuit, the jitter is evaluated by opening the window timing before. Then, the deviation of the reference clock of the reproduction signal is detected as the value of the jitter.
[0039]
Since the PLL circuit is a feedback circuit, even if the phase is shifted for a long time exceeding the operation time constant, it is not preferable from the viewpoint of reproducing the subsidiary data. On the other hand, if the modulation section is shorter than the longest pattern when the main data is modulated, the main data is undesirably spectrally disturbed. For example, in a DVD-ROM, main data is recorded in a pattern of 3T to 14T. It is preferable that the modulation section is longer than 14T which is the longest pattern of the main data. Therefore, it is preferable to set the modulation timing for the clock in a range longer than the longest pattern of the main data and shorter than the operation time constant of the reproduction PLL circuit.
[0040]
The mastering process of the optical disc will be described. As is well known, a replica disk is duplicated by forming a stamper as a mold from an optical disk master on which a desired preformat pattern is cut, and performing injection molding using the stamper. Cutting of the optical disk master is performed by an optical disk master exposure apparatus. FIG. 3A shows an embodiment of an optical disk recording apparatus, and shows an optical disk master exposure apparatus 300 used in the mastering process of the present embodiment. In FIG. 3A, reference numeral 301 denotes a first clock generator that generates a first clock, and 302 denotes a second clock generator that generates a second clock. A formatter 303 modulates a reproduction signal from a master tape or the like into a DVD recording electric signal. Reference numeral 304 denotes a switch for switching an input clock signal. A PC 305 controls the clock switch 304 based on a signal from the formatter and pre-stored subsidiary data. Reference numeral 306 denotes a laser cutter for cutting the master optical disc, and reference numeral 307 denotes a basic clock generator.
[0041]
The operation will be described. The first clock generator 301 and the second clock generator 302 generate clocks having different phases based on the output clock from the basic clock generator 307. FIG. 3B shows output clocks of the first clock generator 301 and the second clock generator 302. There is a phase shift of α between the clock 1 output from the first clock generator 301 and the clock 2 output from the second clock generator 302. The clock 2 is ahead of the clock 1 by the phase shift amount of α. Clock 1 and clock 2 have the same frequency. The phase shift can be generated using, for example, a delay circuit.
[0042]
The PC has subsidiary data in its memory in advance. The changeover switch 304 is switched according to the subsidiary data. For example, when the subsidiary data is “0”, the PC controls the changeover switch to select the clock 1, and when the subsidiary data is “1”, the PC controls the changeover switch to select the clock 2. To control. The formatter 303 that has received the reproduction signal from the master tape or the like modulates the reproduction signal into a DVD recording electric signal according to the clock output from the changeover switch 304. By the above operation, the main data can be recorded on the master optical disk and the subsidiary data can be recorded on the clock of the main data at the same time.
[0043]
FIG. 4 shows a schematic logical configuration of the optical disk drive of the present embodiment. 4, reference numeral 401 denotes a modulation circuit that modulates recording main data from a PC or the like into data to be recorded on the optical disc 412. Reference numeral 402 denotes a clock generation circuit that generates a clock, and 403 denotes a clock controller that controls the clock generation circuit 402. Reference numeral 404 denotes a write pulse generation circuit that generates a recording pulse corresponding to a recording position based on the input main data and clock. A laser driver 405 outputs a signal for driving a laser based on a power setting value corresponding to a recording position and a recording pulse. Note that the clock generation circuit can have a function of a clock controller. This is the same in the following description.
[0044]
An optical head 406 writes data on an optical disk and reads data from the optical disk. The optical head 406 typically includes a laser light source, an objective lens, an optical component for guiding a laser beam emitted from the laser light source to the objective lens, an optical modulator for performing signal modulation on the laser beam, and an optical disk. It includes a photodetector for detecting the intensity of reflected light, and servo means for applying autofocus servo and tracking servo to the laser beam emitted from the objective lens.
[0045]
Reference numeral 407 denotes an RF amplifier that amplifies a reproduction signal from the optical head 406. Reference numeral 408 denotes a clock generation circuit that generates a clock for data detection from the reproduction signal amplified by the RF amplifier 407. A data detection circuit 409 detects main data based on the input reproduction signal and clock. A secondary data detection circuit 410 detects secondary data based on a signal from the data detection circuit. A secondary data detection circuit 411 demodulates the secondary data detected by the secondary data detection circuit 410 and demodulates the secondary data necessary for reproduction. It is a demodulation circuit that performs processing.
[0046]
The basic operation of reproduction will be described with reference to FIG. The data (S5-1) read from the optical disk is input to the clock generation circuit 408, and a reference clock is generated (S5-2). The data detection circuit 409 generates a window pulse based on the reference clock (S5-3). Based on the reference clock and the read data, the data detection circuit 409 detects a reproduction signal within the clock window, performs data discrimination, and detects data (S5-4). The data detection circuit 409 detects a data reproduction position in the clock window and outputs a detection signal (S5-5). The secondary data detection circuit 410 detects secondary data based on the detection signal (S5-6), and the demodulation circuit 411 demodulates the detected secondary data (S5-7).
[0047]
This will be specifically described. The optical head 406 reads data from an optical disk and outputs a reproduction signal that is an electric signal. The output reproduction signal is amplified at a predetermined frequency by the RF amplifier 407. The clock generation circuit 408 generates a clock signal from the reproduced signal by feedback processing, and the clock signal and the reproduced signal are input to the data detection circuit 409. The data detection circuit 409 generates a window pulse from the clock signal.
[0048]
The data detection circuit 409 further performs data discrimination based on the presence or absence of a reproduction signal in the window pulse, and detects main data. This data is demodulated by the demodulation circuit to obtain reproduction main data. The data detection circuit 409 further detects a data reproduction position in the clock window, and outputs a detection signal. The detection signal changes according to the phase shift amount. The secondary data detection circuit 410 detects the amount of phase shift from the detection signal and detects secondary data. The detected subsidiary data is input to the demodulation circuit 411, and reproduced subsidiary data, which is reproduced data, is obtained. Incidentally, the subsidiary data can be detected based on the phase difference signal from the clock generation circuit. This will be described in a second embodiment.
[0049]
The basic operation of the recording operation will be described with reference to FIG. The clock generation circuit 402 generates and outputs a plurality of clocks having different phases based on the secondary data (S6-1) obtained from a PC or the like (S6-2). A write pulse is generated based on the output clock and the recording main data (S6-3), and data is recorded on the optical disk based on the write pulse (S6-4).
[0050]
This will be specifically described. Secondary data output from the PC is input to the clock controller 403. The clock controller 403 outputs a control signal to the clock generation circuit 402 according to the subsidiary data. The clock generation circuit 402 outputs a plurality of clocks having different phases in a predetermined section according to the control signal. For example, the clock 1 shown in FIG. 3 can be output in response to the subsidiary data “0”, and the clock 2 can be output in response to the subsidiary data “1”. Each clock has the same reference clock frequency. As described above, the amount of phase shift is preferably 5 to 15% of the period of the reference clock. The length of the section output by each clock is preferably longer than the longest pattern of the main data and shorter than the operation time constant of the reproduction PLL circuit.
[0051]
The main data output from the PC is subjected to necessary modulation in a modulation circuit 401 and input to a write pulse generation circuit 404. The light pal generation circuit 404 generates a recording pulse corresponding to the recording position based on the input main data and the clock from the clock generation circuit. The laser driver 405 controls the optical head by outputting a signal for driving the laser based on the power setting value corresponding to the recording position and the recording pulse. The optical head 406 writes data to an optical disk based on a control signal from the laser driver 405.
[0052]
FIG. 7 is a configuration diagram illustrating an example of the clock generation circuit 402. 7, 701 is a PLL circuit, 702 is a delay circuit, 703 is a switch for selecting and outputting an input signal according to a control signal, and 704 is a frequency oscillator. The signal output from the frequency oscillator is modulated into a predetermined clock signal in the PLL circuit 701 and output. The clock signal from the PLL circuit 701 is branched, and one is input to the switch 703, and the other is input to the switch 703 via the delay circuit 702. The signal input to the switch 703 via the delay circuit 702 has a phase delayed by a predetermined amount as compared with the other signal. The switch 703 selects and outputs one clock signal based on the subsidiary data. The switch 703 of this embodiment selects a clock signal according to a control signal output from the clock controller based on the subsidiary data.
[0053]
According to the present embodiment, by changing the phase of the reference clock of the main data, management information and the like can be recorded on the optical disc as sub-data, thereby improving the security of the optical disc.
[0054]
Embodiment 2 FIG.
FIG. 8 is a logical configuration diagram schematically showing an optical disk drive according to another embodiment. In FIG. 8, elements denoted by the same reference numerals as those in FIG. 4 are substantially the same as the elements described in FIG. 4, and a description thereof will be omitted. In the optical disc of the present embodiment, main data is recorded at a plurality of sections at different reference clock frequencies. In each section, data is recorded with one clock selected from a plurality of reference clocks having different frequencies. By making the subsidiary data correspond to the reference clock frequency in each section, the subsidiary data can be recorded in the clock signal of the main data. With reference to FIG. 2, for example, main data is recorded in the first section of 202 at the reference clock frequency F1. In the second section, main data is recorded at the reference clock frequency F2. In the third section, main data is recorded at the reference clock frequency F1. The section of the reference clock frequency F1 corresponds to the subsidiary data “0”, and the section of the reference clock frequency F2 corresponds to the subsidiary data “1”.
[0055]
In FIG. 8, reference numeral 801 denotes a clock controller that outputs a control signal based on subsidiary data, and 802 denotes a clock generation circuit that outputs clock signals of different frequencies based on a control signal from the clock controller 801. A clock generation circuit 803 outputs a clock based on a reproduction signal from the optical disk. A data detection circuit 804 discriminates main data based on the reproduction signal and the clock signal. A secondary data detection circuit 805 detects secondary data based on the phase difference signal from the clock generation circuit 803. A demodulation circuit 806 performs demodulation processing required for reproducing the detected subsidiary data.
[0056]
With reference to FIG. 10, the basic operation of the reproduction process in the present embodiment will be described. Data read from the optical disk by the optical head 406 (S10-1) is input to the clock generation circuit 803. The clock generation circuit 803 detects a phase shift from the main data (S10-2), and outputs a phase difference signal based on the phase difference between the main data. The clock generation circuit 803 generates and outputs a clock based on the phase difference signal (S10-3). The phase difference signal is input to the secondary data detection circuit 805, and the secondary data detection circuit 805 detects secondary data based on the phase difference signal (S10-4). Thereafter, the demodulation circuit 806 performs necessary demodulation processing on the subsidiary data (S10-5).
[0057]
This will be specifically described. FIG. 9 shows an example of a logical configuration that mainly contributes to the reproduction of the subsidiary data. In FIG. 9, reference numeral 901 denotes a binarizing circuit for binarizing input data based on a predetermined value. Reference numeral 902 denotes a phase comparison circuit that compares the phase difference between two pieces of input data and outputs a phase difference signal based on the phase difference amount. 903 is a loop filter. Reference numeral 904 denotes a VCO (Voltage Controlled Oscillator) that outputs a frequency signal controlled based on an input signal.
[0058]
The reproduction data output from the optical head 406 is amplified by the RF amplifier 407 and then input to the clock generation circuit 803. The reproduction signal is binarized by a binarization circuit and output. The output data is branched, and one is output as a reproduced signal of the main data. The other is input to the phase comparison circuit 902. The clock signal output from the VCO 904 is input to the phase comparison circuit 902. The clock signal is a signal generated based on past reproduction data, and the phase comparison circuit 902 receives the reproduction data and a clock signal.
[0059]
The phase comparison circuit 902 detects a phase difference between the clock signal and the reproduced signal, and outputs a phase difference signal based on the phase difference. The phase difference signal is branched, one is input to the loop filter 903, and the other is input to the secondary data detection circuit 805. The phase difference signal that has passed through the loop filter 903 is input to the VCO 904. The VCO 904 changes the frequency of the output signal based on the input phase difference signal. If there is a phase difference, VCO 904 changes the frequency of the output signal so as to reduce the phase difference.
[0060]
When the reference clock frequency of the main data changes depending on the section, a phase difference occurs between the clock signal from the VCO 904 and the reproduced signal from the binarization circuit 901, and the output from the phase comparison circuit changes. For example, referring to FIG. 2, when the frequency F2 of the second section is higher than the frequency F1 of the first section, when reproducing the data of the second section, the phase of the reproduced data is ahead of the clock signal. . The phase difference comparison circuit 902 outputs a phase difference signal to two pieces of input data based on the amount of phase difference. The VCO 904 increases the frequency of the clock signal so as to reduce the phase difference. As will be understood, the frequency shift must not exceed the allowable jitter range of the reproduced data. It is important that the main data be reproduced normally and modulated within the allowable jitter margin.
[0061]
The secondary data detection circuit 805 detects secondary data based on the phase difference signal. FIG. 9B shows an example of the phase difference signal from the phase comparison circuit 902. By switching the frequency, a peak signal appears in the phase difference signal. The section in which the reference clock frequency is different, that is, the section in FIG. 9B is larger than the maximum mark length and smaller than the time constant of the clock generation circuit. Therefore, it can be distinguished from a phase shift caused by an error. This is because, in a phase shift caused by an error, the peak interval is usually smaller than the maximum mark length. The detected secondary data is input to the demodulation circuit 806, and the demodulation circuit 806 performs demodulation processing required for secondary data reproduction.
[0062]
In the above example, secondary data is detected based on the output from the phase comparison circuit 902. The secondary data can be detected based on the output from the loop filter 903. However, since a signal in which the phase shift is accumulated is output, the phase shift is increased, and there is a possibility that reproduction failure occurs. For this reason, it is necessary to reset the phase shift every time the frequency is switched. Alternatively, the secondary data can be detected based on the output from the VCO 904 whose frequency changes. The frequency of the output signal of the VCO 904 changes in accordance with the change in the frequency of the reference clock accompanying the section transition. Therefore, it is possible to specify the frequency from this signal and detect the subsidiary data.
[0063]
With reference to FIG. 11, the basic operation of the recording operation of the present embodiment will be described. The secondary data output from the PC or the like is obtained (S11-1), and the clock generation circuit 802 generates and outputs a plurality of clocks having different frequencies based on the secondary data (S11-2). A write pulse is generated and output based on the clock signal output from the clock generation circuit 802 and main data input from a PC or the like (S11-3). Data is recorded on the optical disk based on the output write pulse (S11-4).
[0064]
This will be specifically described. Secondary data input from a PC or the like is input to the clock controller 801. Clock controller 801 outputs a control signal based on the subsidiary data. The clock generation circuit 802 outputs clock signals having different frequencies based on a control signal from a clock controller. Clock generation circuit 802 outputs a clock signal having a frequency corresponding to the subsidiary data. For example, the clock generation circuit 802 outputs a clock signal of the frequency F1 corresponding to the subsidiary data “0”, and outputs a clock signal of the frequency F2 corresponding to the subsidiary data “1”. The clock generation circuit 802 can generate and output clocks having different frequencies, for example, by selecting clocks having different frequencies output from the frequency generator using switches. The switch selects a clock signal according to a control signal from the clock controller 801. According to the above example, the switch selects the clock of the frequency F1 by the control signal corresponding to the subsidiary data “0”, and selects the clock of the frequency F2 by the control signal corresponding to the subsidiary data “1”. I do.
[0065]
According to the present embodiment, by changing the reference clock frequency of the main data, management information and the like can be recorded on the optical disc as sub-data, so that the security of the optical disc is improved.
[0066]
Embodiment 3 FIG.
In the optical disc of the present embodiment, the predetermined data recording area has a plurality of divided sections. In each section, main data is recorded by a clock having a predetermined corresponding frequency. The clock assigned to each section is selected from a plurality of clocks having different frequencies. The predetermined data recording area can be set to, for example, part or all of the lead-in or additional recording area.
[0067]
FIG. 12 shows a state where main data is recorded on the optical disc of the present embodiment. The data recording area has m divided sections. The size of each section can be all the same, or each section can have a different size. A clock of a predetermined frequency is allocated to each section according to predetermined frequency data. The frequency data can include information such as the clock frequency of each section, the size of each section, or the timing for the recording position.
[0068]
The frequency data can be disclosed only to some parties, such as an authorized drive manufacturer or a recording medium manufacturer. Alternatively, the non-disclosure can be improved by recording this frequency data on an IC. Information about the frequency can be recorded in the optical disk in advance. For example, this information can be encrypted and recorded on an optical disk, or its recording position can be recorded privately.
[0069]
The order of the frequencies assigned to each section may follow a predetermined rule or may be random. The same frequency can be assigned to different sections. For example, the frequency f1 can be assigned to the first section, the frequency f2 can be assigned to the second section, and the frequency f1 can be assigned to the third section. A plurality of sections can be assigned to one track. Here, one track is one round of a data string recorded in a spiral. One section can be longer than one track. In the example of FIG. 12, clocks having five different frequencies are assigned to each section. The first section from 0 to n0 has main data recorded with the reference clock f0. In a second section from n0 to n1 following the first section, main data is recorded with the reference clock f1. In the section from n (m-4) to n (m-3), main data is recorded with the reference clock f0. In a subsequent section, that is, a section from n (m-3) to n (m-2), main data is recorded by the reference clock f4. In the example of FIG. 12, a plurality of sections to which the same frequency is assigned can have different sizes. The order of the frequencies assigned to the continuous sections is random.
[0070]
Since the clock frequency to be assigned and the timing for the recording position are determined in advance, secure data reproduction can be achieved. The reference clock frequency is selected from a plurality of clock frequencies and is assigned to each section. Further, the recording amount (or the number of recording clocks) in each section is set corresponding to the assigned frequency. In reproducing the optical disk by the driving device, signal processing can be performed while predicting that the value of the clock frequency fluctuates in advance.
[0071]
The driving device can accurately reproduce the optical disk by changing the clock signal to a clock having a predetermined frequency at a predetermined timing according to frequency data set in advance. If the drive device reproduces data without knowing the relationship between the recording timing and the frequency step, an error occurs. It is important for the drive to know the relationship between the recording timing and the frequency step in order to ensure security.
[0072]
By setting the amount of frequency change small under the condition that no error occurs, it is possible to perform the same processing as the reproduction of the secondary data broadcast in the previous jitter detection. That is, although the main data can be normally reproduced, the reproduction of the subsidiary data proceeds in parallel. Security can be improved by using the secondary data obtained here.
[0073]
FIG. 13 is a configuration diagram schematically showing the driving device of the present embodiment. 13, elements denoted by the same reference numerals as those in FIG. 4 are substantially the same as corresponding elements in FIG. 4, and description thereof will be omitted. In FIG. 13, reference numeral 1301 denotes a memory for recording frequency data; 1302, a clock controller for outputting a control signal based on the frequency data; 1303, based on frequency data which is data relating to a clock frequency corresponding to a plurality of data storage sections; A clock generation circuit that generates and outputs a clock having a predetermined frequency for a predetermined period at a predetermined timing.
[0074]
1304 is a memory for recording frequency data. A clock controller 1305 outputs a control signal based on frequency data. A clock generation circuit 1306 generates and outputs a clock having a predetermined frequency for a predetermined period based on predetermined frequency data based on predetermined frequency data. A detection unit 1307 detects main data based on a clock and a reproduced signal. Circuit.
[0075]
With reference to FIG. 14, the basic operation of the reproduction process by the driving device will be described. Data is read from the optical disk (S14-1). Frequency data previously stored in a memory or recorded on an optical disk is obtained (S14-2), and a clock is generated based on the frequency data (S14-3). A clock window is generated from the generated clock (S14-4), and main data is detected based on the clock window and the read reproduction signal (S14-5).
[0076]
The reproduction operation will be specifically described. Data read from the optical disk by the optical head 406 is output as a reproduction signal that is an electric signal. The reproduction signal is amplified by the RF amplifier 407 and then input to the clock generation circuit 1306. The clock controller 1305 acquires frequency data from the memory 1304, and outputs a control signal to the clock generation circuit 1306 based on the frequency data. The frequency data has information on the clock frequency and the change timing of the clock frequency.
[0077]
The clock generation circuit 1306 receives information on the frequency allocated to each section from the clock controller 1305 according to the control signal, and generates and outputs a reproduction clock of the main data based on the information and the reproduction signal. The clock generation circuit 1306 can change from the current clock frequency to the next clock frequency in a synchronized state by knowing the next frequency and the frequency change timing in advance. The data detection circuit 1307 generates a window pulse from the clock signal. The data detection circuit 1307 further performs data discrimination based on the presence or absence of a reproduced signal in the window pulse, and detects main data. The data is obtained from the generated main data by a demodulation circuit.
[0078]
With reference to FIG. 15, a basic operation in recording data will be described. Frequency data previously recorded in a memory or the like is acquired (S15-1), and clocks having different frequencies are sequentially generated and output based on the frequency data (S15-2). A write pulse is generated and output based on the output clock and main data input from a PC or the like (S15-3). The main data is recorded on the optical disk based on the output write pulse (S15-4).
[0079]
This will be specifically described. The memory 1301 has frequency data in advance. The clock controller 1302 obtains frequency data from the memory 1301, and outputs a control signal based on the frequency data. The clock generation circuit 1303 changes the frequency at a predetermined timing based on the control signal and outputs a clock signal. The frequency data has information on the clock frequency and the timing at which the clock frequency is changed.
[0080]
The clock generation circuit 1305 can output a clock signal whose frequency changes in accordance with preset frequency data. The clock generation circuit 1305 can output clock signals having different frequencies, for example, by selecting a plurality of generated clock signals with a switch. The switch selects a predetermined clock signal at a predetermined timing.
[0081]
According to the present embodiment, since data is recorded on a recording medium according to a predetermined timing and frequency, security of the recording medium can be improved.
[0082]
【The invention's effect】
According to the present invention, it is possible to drive the recording medium more securely.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an optical disc according to a first embodiment.
FIG. 2 is a diagram showing a recording state of subsidiary data in the first embodiment.
FIG. 3 is a diagram showing a configuration of an optical disk master exposure apparatus in the first embodiment.
FIG. 4 is a diagram illustrating an optical disk drive according to the first embodiment.
FIG. 5 is a flowchart illustrating a method of reproducing subsidiary data according to the first embodiment.
FIG. 6 is a flowchart illustrating a method of recording subsidiary data according to the first embodiment.
FIG. 7 is a diagram illustrating a clock generation circuit for recording subsidiary data according to the first embodiment.
FIG. 8 is a diagram illustrating an optical disc driving device according to a second embodiment.
FIG. 9 is a diagram illustrating a clock generation circuit used for secondary data reproduction in the second embodiment.
FIG. 10 is a flowchart illustrating a method of reproducing subsidiary data according to the second embodiment.
FIG. 11 is a flowchart illustrating a method for recording subsidiary data according to the second embodiment.
FIG. 12 is a diagram illustrating a recording state of main data according to a third embodiment.
FIG. 13 is a diagram illustrating an optical disc driving device according to a third embodiment.
FIG. 14 is a flowchart illustrating a method for reproducing main data according to the third embodiment.
FIG. 15 is a flowchart illustrating a main data recording method according to the third embodiment.
[Explanation of symbols]
301 first clock generator, 302 second clock generator, 303 formatter, 304 switch, 305 PC, 306 laser cutter, 307 basic clock generator, 401 modulation circuit, 402 clock generation circuit, 403 clock controller, 404 write pulse generation Circuit, 405 laser driver, 406 optical head, 407 RF amplifier, 408 clock generation circuit, 409 data detection circuit, 410 secondary data detection circuit, 411 demodulation circuit, 412 optical disk, 701 PLL circuit, 702 delay circuit, 703 switch, 704 Frequency oscillator, 801 clock controller, 802 clock generation circuit, 803 clock generation circuit, 804 data detection circuit, 805 secondary data detection circuit, 806 demodulation circuit, 901 binarization circuit, 902 phase comparison Road, 903 loop filter, 904 VCO, 1301 memory, 1302 a clock controller, 1303 a clock generation circuit, 1304 a memory, 1305 a clock controller, 1306 a clock generation circuit, 1307 detection circuit

Claims (25)

A recording medium in which main data is recorded based on a reference clock in a data recording area divided into a plurality of sections,
A first section in which main data is recorded in the reference phase arrangement of the reference clock;
A second section in which main data is recorded based on the reference clock in a different phase arrangement from the first section;
Recording medium comprising: The recording medium according to claim 1, wherein a phase shift amount between the first section and the second section is in a predetermined range. The data recording area has a plurality of second sections,
3. The recording medium according to claim 2, wherein each of the plurality of second sections has a phase shift amount delayed or advanced with respect to the reference phase arrangement. 3. The recording medium according to claim 2, wherein a phase shift amount between the first section and the second section is 5 to 15% of the reference clock cycle. 3. The recording medium according to claim 2, wherein a phase shift amount between the first section and the second section is less than 20% with respect to a reproduction reference clock window of the recording medium. The recording medium according to claim 2, wherein a minimum section of the second section is longer than a longest mark modulated by the reference clock. The recording medium according to claim 6, wherein subsidiary data is recorded by the first section and the second section. A recording medium in which main data is recorded based on a reference clock in a data recording area divided into a plurality of sections, wherein the data recording area is
A first section in which main data is recorded in the reference phase arrangement of the reference clock;
A second section in which main data is recorded with a phase shift amount within a range of 5 to 15% of the reference clock cycle from the reference phase arrangement;
Secondary data is recorded based on the phase shift amount,
recoding media. A recording medium in which main data is recorded based on a plurality of clocks in a data recording area having a plurality of divided sections,
Each section of the plurality of sections has data recorded at a clock frequency assigned to each section,
A clock frequency is assigned to each of the plurality of sections according to preset frequency data,
A recording medium wherein the clock frequency is different in at least one track. A recording medium in which main data is recorded based on a plurality of clocks in a data recording area having a plurality of divided sections,
Each section of the plurality of sections has data recorded at a predetermined clock frequency,
The data recording area is
A plurality of first sections having data recorded at a first clock frequency;
A second section having data recorded at a second frequency different from the first clock frequency, the second section being a section that is continuous with the one first section. The recording medium according to claim 9, wherein each section has a predetermined section length. A recording medium in which main data is recorded based on a plurality of clocks in a data recording area having a plurality of divided sections,
Each section of the plurality of sections has data recorded at a clock frequency assigned to each section,
A recording medium on which subsidiary data is recorded based on a clock frequency assigned to each section. 13. The recording medium according to claim 12, wherein the minimum section of the plurality of sections records subsidiary data in units of a section longer than a longest mark modulated by a clock assigned to each section. An apparatus for recording and / or reproducing a recording medium,
Reading means for reading main data recorded on the recording medium,
Based on the read main data, detecting means for detecting phase data of the main data,
Based on the phase data detected by the detection means, to demodulate the secondary data, secondary data demodulation means,
An apparatus comprising: 15. The apparatus according to claim 14, wherein the detection unit detects a phase shift amount between data of the main data based on detection of a data reproduction position in a data clock window. 15. The apparatus according to claim 14, wherein the detecting unit detects a phase shift amount between the main data based on a phase difference signal from a clock reproducing unit that reproduces a clock based on the main data. A method for recording and / or reproducing a recording medium,
A reading step of reading main data recorded on the recording medium,
Based on the read main data, a detection step of detecting phase data of the main data,
Based on the phase data detected by the detection means, to demodulate the secondary data, a secondary data demodulation step,
Having a method. An apparatus for recording and / or reproducing a recording medium,
Reading means for reading main data recorded on the recording medium,
Detecting means for detecting a clock frequency of the main data based on the read main data,
Based on the frequency detected by the detection means, to demodulate the secondary data, secondary data demodulation means,
An apparatus comprising: An apparatus for performing recording and / or reproduction of a recording medium, wherein different frequencies are assigned to a plurality of data storage sections,
A memory having frequency data for setting a clock frequency corresponding to the plurality of data storage sections,
Based on the frequency data stored in the memory, to generate a clock frequency for the recording medium, clock frequency generation means,
An apparatus that performs a process of recording or reproducing data in the data storage section based on the generated clock frequency. A method for performing recording and / or reproduction on a recording medium, wherein different frequencies are assigned to a plurality of data storage sections,
Generating a clock frequency for the recording medium based on frequency data for setting a clock frequency corresponding to the plurality of data storage sections;
Performing a recording or reproducing process of data in the data storage section based on the generated clock frequency;
A method comprising: Main data recorded based on the reference clock,
Secondary data recorded by modulating the phase of the reference clock,
A recording medium having: An apparatus for recording and / or reproducing a recording medium,
Clock generation means for generating a clock used for recording main data on the recording medium,
A recording unit that records data on the recording medium based on a clock from the clock generation unit;
A memory for recording the subsidiary data,
An apparatus, wherein the clock generator outputs a clock with a phase changed based on the subsidiary data recorded in the memory. An apparatus for recording and / or reproducing a recording medium,
Clock generation means for generating a clock used for recording main data on the recording medium,
Recording means for recording main data on the recording medium based on a clock from the clock generation means,
A memory for recording the subsidiary data,
An apparatus, wherein the clock generation means changes an output clock frequency based on subsidiary data recorded in the memory. A method for recording and / or reproducing a recording medium,
Generating a clock used for recording main data on the recording medium;
Recording data on the recording medium based on a clock from the clock generation unit,
The method of generating a clock, wherein a clock is generated such that an output clock is out of phase based on subsidiary data recorded in a memory. A method for recording and / or reproducing a recording medium,
Generating a clock used for recording main data on the recording medium;
Recording data on the recording medium based on a clock from the clock generation unit,
The method of generating a clock, wherein the clock is generated such that an output clock frequency changes based on subsidiary data recorded in a memory.

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