WO2005076262A1

WO2005076262A1 - Information recording medium

Info

Publication number: WO2005076262A1
Application number: PCT/JP2005/001340
Authority: WO
Inventors: Keiji Katata; Takeshi Koda; Eiji Muramatsu
Original assignee: Pioneer Corporation
Priority date: 2004-02-06
Filing date: 2005-01-31
Publication date: 2005-08-18

Abstract

An information recording medium has a groove track formed in advance and capable of recording the recording data and includes: (i) a main recording area capable of detecting clock information (wobble) and address information (LPP); (ii) a recording area (RAM area) including a latter part area following the main recording area along the groove track; and a reproduction-dedicated area (ROM area) containing clock information, having an emboss pit string formed in advance corresponding to predetermined pre-data following the recording area along the groove track, and capable of detecting clock information. In order to prevent recording of the recording data in the reproduction-dedicated area, the clock information and the address information cannot be detected in the latter part area.

Description

Specification

Information recording medium

Technical field

The present invention relates to a technical field of an information recording medium such as a DVD.

Background art

[0002] A part of a recordable information recording medium such as a CD-RZW or a DVD-RZW is made a read-only area from the time of manufacture, and programs and data are written in this read-only area (referred to as a "ROM area" in this application as appropriate). ), There is a demand to record it in advance and then distribute it to the market. In particular, since there is no extra cost for creating a read-only area of a recordable media information recording medium at the time of manufacture, it is highly convenient for distribution of programs and data. When program data is updated or new data is created, write it to a recordable area (referred to as “RAM area” as appropriate in this application) to ensure consistent handling of program data. Can be. The ROM area of the recordable information recording medium is created with the same recording pits (Readable Emboss) as the read-only information recording medium. Usually, in a recordable information recording medium, a recording film such as a dye film is formed in the entire area including the ROM area and the RAM area. Therefore, if data is written into the ROM area in the same manner as the RAM area, that is, if a laser for writing is irradiated, the characteristics of the ROM area are destroyed and reading becomes impossible.

[0003] Therefore, as described in Patent Documents 1 and 2 and the like, in this type of recordable information recording medium, in order to ensure signal read performance in the ROM area, the ROM area includes an LPP. (Land PrePit) and other techniques for canceling the formation of address information are disclosed!

[0004] Further, as described in Patent Document 3, in order to solve the problem that data is overwritten in the ROM area following the RAM area, an ATIP (Absolute Time In Pre- groove) signal, that is, a technique for stopping recording of address information in advance. More specifically, it includes a ROM area in which the first session data is recorded by pits having irregularities, and a first RAM area provided on the outer peripheral side of the powerful ROM area and capable of recording data of the second session, Another data is overwritten in the ROM area In order to prevent the ATIP signal from being recorded in the head area of the ROM area, a technique for stopping recording of the ATIP signal has been disclosed.

[0005] Power! However, if the current recordable optical disc has a! / ヽ area that cannot be recorded, that is, if there is a read-only area, it is impossible to record in the disc format such as the identification information of the optical disc that is read first. Address information is defined. For example, a technology has been developed in which a recording drive such as a disk drive is controlled so as not to recognize and record an unrecordable area.

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2001-307329

Patent Document 2: Japanese Patent Application Laid-Open No. 2002-42347

Patent Document 3: JP 2003-281738 A

Patent Document 4: JP 2001-148140 A

Patent Document 5: JP-A-2003-157572

Patent Document 6: Japanese Patent Application Laid-Open No. 2003-196886

Patent Document 7: JP-A-10-308038

Disclosure of the invention

Problems to be solved by the invention

[0007] However, in Patent Document 3 described above, if an address signal such as LPP or ATIP cannot be read depending on the recording drive, the address signal is complemented in synchronization with a wobble signal. Some have circuits, which are not enough to prevent erroneous writing.

[0008] In addition, according to the above-described technique, when a new standard is adopted and the address range of the read-only area is changed, the conventional recording drive cannot identify the address range of the read-only area based on the new standard. Therefore, in some cases, erroneous writing to the read-only area has a technical problem.

[0009] Therefore, the present invention has been made in view of, for example, the above-described problem, and aims to prevent erroneous writing that cannot be read in a read-only area that is a part of a recordable information recording medium. An object of the present invention is to provide an information recording medium, an information recording device and a method capable of performing the above. Means for solving the problem

[0010] In order to solve the above-mentioned problems, the information recording medium according to claim 1 of the present invention has a groove track on which recording data can be recorded, and (i) clock information (wobble) and A recording area including a main recording area where address information (LPP) can be detected and (ii) a rear area following the main recording area in a direction along the groove track (RAM area: recordable area ), The clock information is recorded, and an embossed row corresponding to predetermined pre-data is formed in advance in the direction along the groove track, behind the recording area, and the reproduction is performed so that the clock information can be detected. A dedicated area (ROM area), and the clock information and the address information are detected in the rear area in order to prevent the recording data from being recorded in the read-only area. It is formed to be impossible.

Brief Description of Drawings

FIG. 1 shows a basic structure of an optical disc according to an embodiment of the information recording medium of the present invention, wherein an upper part is a schematic plan view of an optical disc having a plurality of recording areas, and a lower part corresponding thereto. The side part is a schematic conceptual diagram of the recording area structure in the radial direction.

FIG. 2 is a partially enlarged perspective view of a recording surface of the optical disc according to the embodiment.

FIG. 3 is a schematic conceptual diagram showing clock information and address information necessary for recording to obtain a wobbling force of a groove track in an optical disc according to an embodiment of the information recording medium of the present invention.

FIG. 4 is a schematic conceptual diagram conceptually showing a recording area including a double track to which the basic principle of an optical disc according to an embodiment of the information recording medium of the present invention is applied.

FIG. 5 is a schematic conceptual diagram showing a specific example of a recording area including a double track to which the basic principle of an optical disc according to an embodiment of the information recording medium of the present invention is applied.

FIG. 6 is a schematic conceptual diagram showing another specific example in which attention is paid to a wobble signal to which the basic principle of an optical disc according to an embodiment of the information recording medium of the present invention is applied.

FIG. 7 is a schematic structural diagram of a data area showing a specific example of a recording area of an optical disc according to a comparative example.

FIG. 8 is a schematic data showing another specific example of the recording area of the optical disc according to the comparative example. It is a structural diagram of an area.

FIG. 9 is a block diagram showing an overall configuration of an information recording / reproducing apparatus for recording / reproducing an information recording medium of the present invention.

Explanation of symbols

[0012] 1 ··· Center hole, 10 ··· Track, 11 ··· Sector, 100 ··· Optical disk, 101 ··· Lead-in area, 102 ··· Data area, 103 ···· Lead-out area , 106 ··· Transparent substrate, 107 ··· Recording layer, 108 ··· Reflective layer, 109 ··· Poble, 150 OPC area, 200 ··· Information recording / reproducing device, 201 ··· Objective lens, 202 ··· Optical pickup, 203 ··· spindle motor, 204 · · head amp, 210 · · · sum generation circuit, 211 · · · pit data demodulation circuit, 212 · · · pit data correction circuit, 213 · · · Interface, 220: Push-pull signal generation circuit, 221 ··· Lonos filter, 222 ··· Servo K 227 · “RAND table, 228 ··· Spread spectrum demodulation circuit, 230 ··· Spread spectrum data Regeneration circuit, SS: Spread spectrum data, CK1: 1st Clock signal, CK2-2nd clock signal GT: Groove track, LT: Land track, LB: Laser beam, LPP: Land prepit

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment of Information Recording Medium)

Hereinafter, an information recording medium according to an embodiment of the present invention will be described.

According to the embodiment of the information recording medium of the present invention, a group track capable of recording recording data is formed in advance, and (i) a main recording capable of detecting clock information (wobble) and address information (LPP). A recording area (RAM area: recordable area) including an area and (ii) a rear area following the main recording area in a direction along the groove track, and the clock information is recorded; A read-only area (ROM area) in which an emboss pit row corresponding to predetermined pre-data is formed in advance in the direction along the groove track and behind the recording area, and the clock information can be detected. In the rear area, the clock information and the address information are formed so as to be undetectable in order to prevent the recording data from being recorded in the reproduction-only area.

[0015] According to the embodiment of the information recording medium of the present invention, in a rear area following the main recording area in a direction along the group track in the recording area, clock information is not transmitted. For example, it is configured so that a pebble is hardly or completely formed in order to be undetectable. At the same time, pre-format information such as LPP or ATIP is not recorded so that address information cannot be detected! RU

[0016] Therefore, if an information recording device described later attempts to write erroneously to the read-only area after recording in the recording area, it is determined that clock information and address information cannot be detected in the rear area. Therefore, an error occurs in the recording operation and the recording operation is stopped, so it is possible to prevent erroneous writing in the read-only area regardless of the specifications of the information recording device and the recording control procedure .

[0017] If an information recording device such as a disk drive records only two pieces of information necessary for writing to a recording area, that is, only one of clock information and address information, for example, the OPC process in the OPC process is performed. There is a possibility that the test writing is performed only in the area, the OPC area is protruded, and writing to the read-only area is continued by mistake.

On the other hand, according to the present embodiment, if an erroneous write is attempted to be performed on the read-only area via the information recording apparatus after recording on the recording area, the clock information and the address are recorded in the rear area. Since the information cannot be detected, an error occurs during the recording operation, and the recording operation is stopped.Therefore, regardless of the specifications of the information recording device or the recording control procedure, an error in the read-only area may occur. This makes it possible to prevent writing. In other words, in the existing optical information recording media such as CDs, DVDs, Blu-ray discs, etc., it is possible to maintain the compatibility of the media format and effectively prevent erroneous writing in the read-only area. It can be prevented.

[0019] In one aspect of the embodiment of the information recording medium of the present invention, the clock information is recorded in the main recording area by a wobble in the groove track, and in the rear area, The amplitude of the pebble is gradually decreasing.

[0020] According to this aspect, in the rear region, for example, the amplitude of the pebble is gradually reduced, and AM (Amplitude Modulation) is performed. Therefore, in the rear area, the clock information gradually becomes undetectable even when the main recording area force is applied to the rear area, so that erroneous writing to the reproduction-only area can be more reliably prevented. . In another aspect of the embodiment of the information recording medium of the present invention, the address information is recorded in each of the main recording areas by land pre-pits (LPP).

According to this aspect, the main recording area and the rear area can be significantly distinguished depending on the presence or absence of a land pre-pit (LPP). Therefore, in the rear area, the address information out of the clock information and the address information cannot be detected more reliably, so that erroneous writing to the read-only area can be more reliably prevented.

In another aspect of the embodiment of the information recording medium of the present invention, the read-only area includes: (i) a main playback area in which the clock information can be detected; and (ii) a direction along the groove track. And a front region following the main reproduction region.

[0024] According to this aspect, the front region and the main reproduction region in which clock information can be detected can be significantly distinguished by, for example, the presence or absence of a pebble. Since the clock information among the clock information and the address information cannot be detected more reliably, it is possible to more reliably prevent erroneous writing in the read-only area.

According to this aspect, in the main reproduction area, the clock information is formed by the wobbles of the embossed pit row, and in the front area, the amplitude of the wobbles gradually increases. It may be configured as follows.

With this configuration, for example, the front area and the main reproduction area where only “Null” data is recorded can be remarkably distinguished by the magnitude of the amplitude of the pebble. In addition to the area, in the front area, the clock information of the clock information and the address information cannot be detected more reliably, so that it is possible to more reliably prevent erroneous writing to the read-only area. Become.

According to this aspect, the read-only area is formed with land pre-pits.

[0028] With this configuration, the read-only area and the recording area can be remarkably distinguished depending on the presence or absence of the land pre-pit, so that the clock information and the address information can be detected more reliably in the rear area described above. Since it becomes impossible, erroneous writing to the read-only area can be more reliably prevented. [0029] Such an operation and other advantages of the present embodiment will be apparent from examples described below.

As described above, according to the embodiment of the information recording medium of the present invention, the main recording area, the rear area formed so that the clock information and the address information cannot be detected, and the reproduction area Dedicated area enables compatibility with existing optical information recording media such as CDs, DVDs, Blu-ray discs and other media formats. At the same time, erroneous writing to the read-only area can be effectively prevented.

Example

[0031] (Information recording medium)

Hereinafter, embodiments of the information recording medium of the present invention will be described with reference to FIGS. 1 to 8.

First, with reference to FIG. 1 and FIG. 2, the basic structure of the optical disc of the present embodiment will be described. FIG. 1 shows a basic structure of an optical disc according to an embodiment of the information recording medium of the present invention, wherein an upper part is a schematic plan view of an optical disc having a plurality of recording areas, and a lower part corresponding thereto. The portion is a schematic conceptual diagram of the recording area structure in the radial direction. FIG. 2 is a partially enlarged perspective view of the recording surface of the optical disc of the present embodiment.

[0033] The information recording medium according to the present embodiment is a rewritable optical disc capable of recording many times and reproducing many times by a reversible change recording method by various kinds of heating or the like.

As shown in FIG. 1, the optical disc 100 is, for example, on a recording surface on a disc main body having a diameter of about 12 cm like a DVD, with the center hole 1 being the center and the inner circumferential force being directed toward the outer circumferential side. An OPC area 150, a lead-in area 101, a data area 102, and a lead-out area 103 according to the example are provided. In particular, the OPC area 150 is provided for detecting the optimum recording laser power, that is, for calibrating the recording laser power. In each recording area, for example, tracks 10 such as groove tracks and land tracks are alternately provided in a snail or concentric manner centering on the center hole 1. As shown in FIG. 2, in the present embodiment, the optical disc 100 is placed on a disc-shaped transparent substrate 106 (on the lower side in FIG. 2), and reversible change recording (destruction) by heating or the like constituting an information recording surface is performed. A (write) type recording layer 107 is laminated, and a reflective layer 108 is further laminated thereon (the lower side in FIG. 2). Groove tracks GT and land tracks LT are alternately formed on the information recording surface of the recording layer 107 which also has a surface force. At the time of recording and playback of the optical disc 100, for example, as shown in FIG. 2, the laser beam LB is irradiated onto the groove track GT via the transparent substrate 106. For example, at the time of recording, by irradiating the laser beam LB with the recording laser power, reversible change recording is performed by heating the recording layer 107 or the like according to the recording data. On the other hand, at the time of reproduction, by irradiating the laser beam LB with a reproduction laser power weaker than the recording laser power, the recording data recorded by the reversible change recording by heating the recording layer 107 or the like is executed.

The groove track GT, the land track LT, the wobbled 109, the land pre-pit LPP, and the like will be described later in detail.

In FIG. 1 again, data is recorded on the track 10 in units of 1 unit of sector 11, for example, 1 ECC block (cluster) which is a management unit in which 16 data units are collected. This 1ECC block is a management unit based on preformat address information that can be corrected.

The present invention is not particularly limited to the optical disc 100 having four recording areas as shown in FIG. For example, the OPC area 150 does not have to be located on the innermost circumference.For example, the OPC area 150 may be located in the lead-in area 101, the data area 102, or the lead-out area 103 in FIG. Alternatively, it may be located between the lead-in area 101 and the data area 102, between the data area 102 and the lead-out area 103, or on the outer peripheral side of the lead-out area 103. The presence of the lead-in area 101 and the lead-out area 103 is optional, and two recording areas, an OPC pit or an OPC area 150 for recording an OPC pattern and a data area 102 for recording data, are provided. It is sufficient if at least it is provided. As a matter of fact, such OPC areas 150 may be arranged as one unit or divided into a plurality of units.

Next, with reference to FIGS. 3 to 6 and FIG. 2 described above, the basic principle of the optical disc according to the embodiment of the information recording medium of the present invention will be described in detail with reference to the drawings. First, with reference to FIG. 3, a description will be given of clock information and address information necessary for recording in which the wobbling force of a groove track can be obtained in the optical disc according to the embodiment of the information recording medium of the present invention. Here, FIG. 3 is a schematic conceptual diagram showing clock information and address information necessary at the time of recording to obtain the wobbling force of the groove track in the optical disc according to the embodiment of the information recording medium of the present invention.

As shown in FIGS. 3 (a), (b) and (c), in the optical disc according to the present embodiment, the groove track GT is oscillated at a constant amplitude and a constant spatial frequency. That is, the group track GT is wobbling, and the cycle of the wobble 109 is set to a predetermined value. It should be noted that the preformat address information may be recorded in advance by modulating the groove track GT wobble 109 by a predetermined modulation method such as frequency modulation or phase modulation.

[0042] As shown in Fig. 3 (b), in the case of CD-RZW, due to a delicate frequency change, the address information on the optical disk becomes absolute time information called ATIP (Absolute Time In Pre-groove) signal. Incorporated as

As shown in FIG. 3C, in the case of DVD-RZW, address pits called land pre-pits LPP indicating pre-format address information are formed on the land track LT.

The two types of addressing described above, ie, disk 109 and ATIP or land pre-pit LPP, control of disk rotation during recording and generation of a recording clock (a specific example of “clock information” according to the present invention), Information necessary for data recording such as a recording address (an example of “address information” according to the present invention) can be obtained.

More specifically, for example, in order to write in a recordable area such as a disk drive, for example, in a recordable area such as a RAM area (which constitutes an example of the “recording area” according to the present invention), For example, clock information and address information used for writing are required in addition to the recording parameters such as the optimum recording power of the laser beam and the recording strategy. Usually, address information may be temporarily unreadable during writing due to missing or noise. To cope with this, the recording drive has a function to supplement missing address information with clock information. In the comparative example described later, only the address information is lost. After the address information is acquired in the area, etc., even if an optical pickup enters the read-only area such as the ROM area, writing to the read-only area is erroneously continued by the function to supplement the address information described above. there is a possibility.

Further, since the clock information is a force extracted from the wobble, the wobble is also used for controlling the rotation of the optical disk. Therefore, if the wobble is eliminated in a wide range, the rotation of the optical disk becomes abnormal and the read-only area cannot be read. . Therefore, as will be described later, both the clock information and the address information used for writing in the “rear area” according to the present invention, which is located forward of the track direction from the boundary from the recording area to the reproduction-only area, are used. Is formed so that it cannot be detected.

[0047] As described above, if an erroneous write is attempted to be performed in the read-only area after recording in the recording area by the information recording apparatus described later, it is determined that the clock information and the address information cannot be detected in the rear area. Therefore, an error occurs in the recording operation and the recording operation is stopped, so that erroneous writing to the read-only area can be prevented regardless of the specifications of the information recording apparatus and the recording control procedure. In other words, it is possible to maintain the compatibility of the media format of existing optical information recording media such as CDs, DVDs, and Blu-ray discs, and to prevent erroneous writing in the read-only area. Can be prevented.

Next, with reference to FIGS. 4 to 6, the recording area including the groove track to which the basic principle of the optical disc according to the embodiment of the information recording medium of the present invention is applied will be described in more detail. FIG. 4 is a schematic conceptual diagram conceptually showing a recording area including a groove track to which the basic principle of an optical disc according to an embodiment of the information recording medium of the present invention is applied. FIG. 5 is a schematic conceptual diagram showing a specific example of a recording area including a groove track to which the basic principle of the optical disc according to the embodiment of the information recording medium of the present invention is applied. FIG. 6 is a schematic conceptual diagram showing another specific example in which attention is paid to a double signal to which the basic principle of the optical disc according to the embodiment of the information recording medium of the present invention is applied.

As shown in FIG. 4, the optical disc according to the present embodiment uses the optical disc in order to prevent clock information from being extracted in the area near the boundary where the area shifts from the recordable area to the read-only area. Is not formed. At the same time, preformatting the address information No information is formed. More specifically, in the read-only area, LPP (Land PrePit), which is address information, is not formed in the DVD-RW Verl. 1 format according to the standard. This LPP has not been formed. Therefore, writing cannot be started in the read-only area.

As shown in FIG. 5, one specific example of the optical disk according to the present embodiment is a DVD-RZW or other optical information recording medium that reproduces, for example, the area of the first border (first bordered zone). It is a dedicated area. With reference to the boundary that transitions from the recordable area to the read-only area, the 10 ECC blocks located behind the recording track direction and the 6 ECC blocks located ahead of the boundary in the recording track direction The amplitude is made very small and AM (Amplitude Modulation) is applied (see Fig. 6 (a)). In particular, it is preferable that the change when the amplitude starts to decrease and when the amplitude ends increase gradually. This is because it is possible to further simplify the manufacturing process. More specifically, the comparator in the information recording / reproducing apparatus described later cannot detect the wobble signal from the band-pass filter. In particular, the aforementioned “10 ECC blocks” constitute one specific example of the “rear area” in the “recording area” according to the present invention. At the same time, the “6 ECC block” constitutes a specific example of the “front area” in the “read only area” according to the present invention. It is preferable that an LPP (Land PrePit) is not provided in the 10 ECC block which is a rear area in the recording area. Also, as described above, the read-only area of an optical information recording medium such as a DVD-RZW is provided with LPP (Land PrePit), which is address information, according to the standard.

[0051] As another specific example, a configuration may be adopted in which a pebble is almost or completely eliminated (see FIG. 6 (b)). However, more advanced control is required in the manufacturing process. More specifically, the comparator in the information recording / reproducing apparatus cannot detect the wobble signal from the band-pass filter as in the above-described specific example.

As another specific example, the frequency is modulated from, for example, 例えば to ΙΟΚΗζ,

(Frequency Modulation)! /, (See Fig. 6 (c)). For FM! / In the case of FM, the frequency is increased twice or five times! ], Or 1Z2 times, 1Z5 times, etc. In this specific example, more specifically, as in the above-described specific example, the comparator in the information recording / reproducing apparatus can detect the wobble signal from the band-pass filter. Will not be able to.

[0053] In addition, although not shown, as another specific example, the groove track itself may not be formed in advance in at least the 10 ECC block of the 10 ECC block and the 6 ECC block described above. Also in this specific example, more specifically, as in the above-described specific example, the comparator in the information recording / reproducing apparatus cannot detect a small signal having a bandpass filter power.

Next, with reference to FIGS. 7 and 8, which show a comparative example, the effects of the optical disc according to the embodiment of the information recording medium of the present invention will be further studied. FIG. 7 is a schematic structural diagram of a data area showing a specific example of a recording area of an optical disc according to a comparative example. FIG. 8 is a schematic data area structure diagram showing another specific example of the recording area of the optical disc according to the comparative example.

As shown in FIG. 7, in one specific example of the comparative example, when a non-recordable area is created on the inner peripheral side of a recordable optical disc such as a CD-RZW, the reproduction in the lead-in area is performed. In the dedicated area, for example, the ATIP signal storing the recording parameter information such as the optimum recording power of the laser beam and the recording strategy is deleted. Therefore, it becomes impossible to read the recording parameters on the conventional optical disc such as CD-RZW, so that it becomes incompatible with the conventional recordable optical disc and the conventional recording drive can prevent erroneous writing to the read-only area. It might be power.

However, in a recording drive that records data with fixed recording parameters, a power calibration (Power calibration) that detects an optimal recording power value in the OPC area is performed.

If (Calibration) succeeds, even if the address signal cannot be read in the information recording device, the address signal will be complemented in synchronization with the detectable signal, and the OPC area will continue to be recorded on the read-only area. . It cannot be used in a media format that describes recording parameters in a read-only area, such as DVD-RW Verl.

On the other hand, according to the embodiment of the information recording medium of the present invention, when an information recording device described later attempts to erroneously write to the read-only area via recording in the recording area. In the recording track direction, in the area before the read-only area, the clock Since the information and address information cannot be detected, an error occurs in the recording operation and the recording operation is stopped.Therefore, regardless of the specifications of the information recording device and the recording control procedure, incorrect writing to the read-only area Can be prevented. In other words, it is possible to maintain the compatibility of the existing optical information recording media, such as CDs, DVDs, and Blu-ray discs, with respect to the media format, and to prevent erroneous writing in the read-only area. Effective prevention can be achieved.

Next, as shown in FIG. 8, in another specific example of the comparative example, if the current recordable optical disc has an unrecordable area, that is, a read-only area, the optical disc that is read first In the disc format such as the identification information of the disc, address information of an area that cannot be recorded first is defined.For example, a recording drive such as a disc drive does not recognize and record an unrecordable area. Maybe the power that can be controlled as.

However, if a new standard is adopted and the address range of the read-only area changes, the conventional recording drive cannot identify the new standard-based address range of the read-only area. In some cases, erroneous writing is performed in the read-only area.

On the other hand, according to the embodiment of the information recording medium of the present invention, as described above, in the existing optical information recording medium such as CD, DVD, Blu-ray disc, etc. This makes it possible to maintain compatibility of the media format and effectively prevent erroneous writing in the read-only area.

(Information recording / reproducing device)

Next, an information recording / reproducing apparatus for recording / reproducing the information recording medium of the present invention will be described. FIG. 9 is a block diagram showing the overall configuration of an information recording / reproducing apparatus for recording / reproducing an information recording medium according to the present invention. On the optical disc 100, pit data DP synchronized with the first clock signal CK1 is recorded according to the length of the recording mark. The recording mark in this example is a pit, and the track is formed by a pit row. The track has a meandering shape according to the wobble signal WB obtained by spread spectrum modulation of the wobble data DW. The wobble signal WB is synchronized with the second clock signal CK2. The first clock signal CK1 has a frequency N (N is a natural number) times that of the second clock signal CK2. In this example, N = 25, the second clock signal CK2 is 420 KHz, and the first clock signal CK1 is 10.5 MHz. [0062] The information recording / reproducing apparatus 200 includes an optical pickup 202 that irradiates the optical disc 100 with a reproducing beam and outputs a signal corresponding to the reflected light, a spindle motor 203 that controls the rotation of the optical disc 100, and a servo unit 222. Is provided. The first clock signal CK1 and the pit synchronization signal SYNCp are supplied to the servo unit 222. The servo unit 222 executes a focus servo and a tracking servo which are relative position control of the optical pickup 202 and the spindle servo for controlling the rotation of the spindle motor 203 in synchronization with these signals.

The optical pickup 202 includes a laser diode for irradiating a reproduction beam and a four-division detection circuit (not shown). The four-split detection circuit divides the reflected light of the reproduction beam into four areas 1A, 1B, 1C, and ID shown in FIG. 9, and outputs a signal corresponding to the light amount of each area. The head amplifier 204 amplifies each output signal of the optical pickup 202, and outputs the divided read signal la corresponding to the area 1A, the divided read signal lb corresponding to the area IB, the divided read signal lc corresponding to the area 1C, and the area Outputs divided read signal Id corresponding to ID. Note that the optical pickup 202 and the head amplifier 204 correspond to the optical pickup means according to the present invention.

[0064] The sum generation circuit 210 adds the divided read signals la, lb, lc, and Id to generate an addition circuit that outputs a sum read signal SRF. The total reading signal SRF is a signal indicating the length of the recording mark.

The pit data demodulation circuit 211 reproduces the pit data DP based on the total read signal SRF and generates the first clock signal CK1. More specifically, the pit data DP is demodulated using a predetermined table to generate reproduced data. For example, when EFM modulation is used as a modulation method, a process of converting 14-bit pit data DP into 8-bit reproduced data is performed. Further, a descrambling process for rearranging the order of the reproduced data according to a predetermined rule is executed, and the processed reproduced data is output.

The reproduced data thus obtained is supplied to the pit data correction circuit 212 shown in FIG. 9, where it is subjected to error correction processing, interpolation processing, and the like, and then stored in the buffer 213. The interface 214 sequentially reads out the data stored in the notifier 213, converts the data into a predetermined output format, and outputs it to an external device. The push-pull signal generation circuit 220 calculates (la + ld)-(lb + lc) and generates a push-pull signal. The component (la + ld) corresponds to the areas 1A and 1D on the left side in the reading direction, while the component (lb + lc) corresponds to the areas 1B and 1C on the right side in the reading direction. That is, if the reproduction beam is biased to the left with respect to the pit, the push-pull signal becomes positive with respect to the center of the amplitude, and if the reproduction beam is located at the center of the pit, the value of the push-pull signal becomes the center of the amplitude, If the reproduction beam is shifted to the right with respect to the pit, the push-pull signal becomes negative with respect to the center of amplitude. The relative position of the reproducing beam and the pit changes according to the meandering of the track, and the value of the push-pull signal indicates the relative positional relationship between the reproducing beam and the pit. That is, the push-pull signal is a signal corresponding to the meandering of the track.

The push-pull signal is output to the servo unit 222 via the low-pass filter 221. The servo unit 222 performs tracking control based on the push-pull signal. Further, the push-pull signal is supplied to the band pass filter 223. The pass band of the band-pass filter 223 is set so that a wobble signal WB obtained by performing spread spectrum modulation on the wobble data DW during recording can be extracted from a push-pull signal. Accordingly, the bandpass filter 223 constitutes the above-described detection means together with the push-pull signal generation circuit 220, and its output signal is obtained by reproducing the wobble signal WB from the optical disc 100. In particular, in the comparator 224, if erroneous writing is attempted in the read-only area after recording in the recording area, clock information and address information cannot be detected in the rear area according to the present invention. In addition, since an error occurs during the recording operation and the recording operation is stopped, it is possible to prevent erroneous writing to the read-only area regardless of the specifications of the information recording device and the recording control procedure. It becomes. That is, it is possible to make the PLL (Phase Locked Loop) uncontrollable.

[0069] Spread spectrum data reproducing circuit 230 reproduces spread spectrum data SS based on data B. The details of the spread spectrum data reproduction circuit 230 differ depending on the type of modulation used when creating the master disk DS.

[0070] The RAND table 227 stores randomized patterns used for spread spectrum modulation during recording. A randomized pattern is equivalent to a spreading code and uses a random function. V, a bit string generated. The second clock signal CK2 is supplied to the RAND table 227, and random data RND is generated by reading a randomization pattern in synchronization with the second clock signal CK2, and the generated random data RND is spread spectrum. The signal is supplied to the dispersion demodulation circuit 228. Further, the spread spectrum data SS output from the spread spectrum data reproducing circuit 230 is supplied to the spread spectrum demodulation circuit 228.

[0071] The spread spectrum demodulation circuit 228 is configured by a multiplication circuit (for example, an exclusive OR circuit XOR), and reproduces the double data DW by multiplying the spread spectrum data SS by the random data RND. At this time, signals that are not in the original signal band are converted to signals outside the band by multiplication. The reproduced data DW thus reproduced is subjected to error correction in an error correction circuit 229 and then output.

In this embodiment, a rewritable optical disc such as a CD-RZW or a DVD-RZW has been described as a specific example of the information recording medium. However, the present invention is applicable to all CDs using It can also be used for optical information recording media such as large-capacity recording media such as DVDs and Blu-ray discs.

[0073] The present invention is not limited to the embodiments described above, and may be modified as appropriate without departing from the spirit or spirit of the invention which can be read. The medium is also included in the technical scope of the present invention. Industrial applicability

The information recording medium according to the present invention can be used for, for example, a DVD or the like for consumer use or business use that can record various types of information at high density.

Claims

The scope of the claims

[1] A groove track on which recording data can be recorded is formed in advance, and (i) a main recording area where clock information and address information can be detected; and (ϋ) a rear part of the main recording area in a direction along the groove track. A recording area comprising a rear area following

The clock information is recorded, an emboss pit row corresponding to predetermined pre-data is formed beforehand behind the recording area in a direction along the groove track, and a read-only area in which the clock information can be detected is provided.

With

In order to prevent the recording data from being recorded in the read-only area, the rear area is formed so that the clock information and the address information cannot be detected! An optical information recording medium characterized by the above-mentioned.

[2] In the main recording area, the clock information is recorded by a wobble in the groove track,

2. The optical information recording medium according to claim 1, wherein the amplitude of the wobble is gradually reduced in the rear region.

3. The optical information recording medium according to claim 1, wherein the address information is recorded by land pre-pits in the main recording area.

[4] The reproduction-only area includes (i) a main reproduction area in which the clock information can be detected, and (ii) a front area continuing in front of the main reproduction area in a direction along the groove track. The optical recording medium according to claim 1, wherein:

[5] In the main reproduction area, the clock information is formed by a pebble of the embossed pit row,

5. The optical information recording medium according to claim 4, wherein the amplitude of the wobble is gradually increased in the front region.

6. The optical information recording medium according to claim 4, wherein land read pits are formed in the read-only area.