JP3664722B2 - Optical disc medium and reproducing method thereof - Google Patents

Description

  The present invention relates to an optical disc medium and an optical disc apparatus, and more specifically, signals are supplied to both a recording track in a concave portion formed by a guide groove on the disc and a recording track in a convex portion formed between the guide grooves. The present invention relates to an optical disc medium and an optical disc apparatus which are made to record.

  In recent years, as a recording method for a large-capacity rewritable optical disk medium, data is recorded in both the groove portion (also referred to as groove: G) and the groove portion (also referred to as land: L) in order to improve the recording density. A so-called land / groove recording system is being studied. Since the track pitch can be halved with the same groove pitch disk, the effect of increasing the density is great. As described above, the groove portion and the inter-groove portion may be referred to as a concave portion and a convex portion, respectively, as described above.

  Conventional optical disc apparatuses are described in Patent Documents 1 to 4 below.

JP-A-6-176404 JP-A-4-38633 JP-A-7-110944 Japanese Patent Publication No. 7-46430

  First, a conventional land / groove recording type optical disk apparatus will be described. FIG. 11 is a block diagram showing a configuration of a conventional optical disc apparatus described in Patent Document 1. In FIG. In FIG. 11, 100 is an optical disk, 101 is a semiconductor laser, 102 is a collimating lens that converts laser light from the semiconductor laser 101 into parallel light, 103 is a half mirror, and 105 is a parallel light that has passed through the half mirror 103. An objective lens 105 is a photodetector that receives reflected light from the optical disc 100 that has passed through the objective lens 104 and the half mirror 103, and is divided into two in parallel with the track direction of the disc to obtain a tracking error signal. It consists of two light receiving parts. Reference numeral 106 denotes an actuator that supports the objective lens 104. A portion 107 surrounded by a dotted line is attached to the head base, and constitutes an optical head. 108 is a differential amplifier to which a detection signal output from the photodetector 105 is input, 109 is a tracking error signal from the differential amplifier 108, and a control signal T1 is input from a system control unit, which will be described later, to the tracking control unit 110. A polarity inversion unit that outputs a tracking error signal. Here, regarding the polarity of the tracking control, when the tracking error signal is input from the differential amplifier 108 to the tracking control unit 110 with the same polarity, tracking pull-in is performed on the recording track of the groove. A tracking control unit 110 receives an output signal from the polarity inversion unit 109 and a control signal T2 from a system control unit 121 (to be described later) and outputs a tracking control signal to the driving unit 120 and the traverse control unit 116 (to be described later). Reference numeral 111 denotes an addition amplifier that receives a detection signal output from the photodetector 105 and outputs a sum signal. Reference numeral 112 denotes a high-frequency component input from the addition amplifier 111, and a digital signal is input to a reproduction signal processing unit 113 and an address reproduction unit 114 described later. The waveform shaping unit 113 outputs a reproduction data to an output terminal. Reference numeral 114 denotes a digital signal input from the waveform shaping unit, and an address reproduction unit that outputs an address signal to an address calculation unit 115 described later. Reference numeral 115 denotes an address signal from the address reproduction unit 114 and control signal T1 from the system control unit 121. The address calculation unit outputs an accurate address signal to the system control unit 121. Reference numeral 116 denotes a traverse control unit that outputs a drive current to a traverse motor 117 described later in response to a control signal T3 from a system control unit 121 described later. Reference numeral 117 denotes a traverse motor that moves the optical head 107 in the radial direction of the optical disc 100. A recording signal processing unit 118 receives recording data and outputs a recording signal to a laser (LD) driving unit 119, which will be described later. 119 receives a control signal T4 from a system control unit 121, which is described later, and a recording signal from a recording signal processing unit 118. Is a laser drive unit that inputs a drive current to the semiconductor laser 101. A driving unit 120 outputs a driving current to the actuator 106. Reference numeral 121 denotes a control signal T1 to T4 output to the tracking control unit 110, traverse control unit 116, address calculation unit 115, polarity inversion unit 109, recording signal processing unit 118, and LD drive unit, and an address signal is input from the address calculation unit 115. System control unit.

  The operation of the conventional optical disc apparatus configured as described above will be described with reference to FIG. The laser beam output from the semiconductor laser 101 is collimated by the collimator lens 102 and converged on the optical disc 100 by the objective lens 104 through the beam splitter 103. The laser beam reflected by the optical disc 100 has information on the recording track, and is guided onto the photodetector 105 by the beam splitter 103 through the objective lens 104. The photodetector 105 converts the change in the light amount distribution of the incident light beam into an electrical signal and outputs the electrical signal to the differential amplifier 108 and the addition amplifier 111, respectively. The differential amplifier 108 performs a current-voltage conversion (IV conversion) on each input current, takes a difference, and outputs it as a push-pull signal. The polarity inversion unit 109 recognizes whether the track being accessed is a land or a groove by the control signal T1 from the system control unit, and inverts the polarity only when the track is a land, for example. The tracking control unit 110 outputs a tracking control signal to the driving unit 120 according to the level of the input tracking error signal, and the driving unit 120 sends a driving current to the actuator 106 according to this signal to record the objective lens 104. Position control in the direction across the track. As a result, the light spot correctly scans the track. On the other hand, the addition amplifier 111 performs addition after current-voltage conversion (IV conversion) of the output current of the light receiving unit 106 and outputs the result as a sum signal to the waveform shaping circuit 112. The waveform shaping circuit 112 data-slices the analog waveform data signal and the address signal with a certain threshold value to form a pulse waveform, and outputs the pulse waveform to the reproduction signal processing unit 113 and the address reproduction unit 114. The reproduction signal processing unit 113 demodulates the input digital data signal, and thereafter performs processing such as error correction and outputs it as reproduction data. The address reproducing unit 114 demodulates the input digital address signal and outputs it to the address calculating unit 115 as position information on the disk. The address calculation unit 115 calculates the address of the accessed sector from the address signal read from the optical disc 100 and the land / groove signal from the system control unit 121. The calculation method will be described later. Based on this address signal, the system control unit 121 determines whether the current light beam is at a desired address. The traverse control unit 116 outputs a drive current to the traverse motor 117 according to the control signal T3 from the system control unit 121 when the optical head is moved, and moves the optical head 107 to the target track. At this time, the tracking control unit 110 temporarily suspends the tracking servo by the control signal T2 from the system control unit 121. During normal reproduction, the traverse motor 117 is driven in accordance with the tracking error signal input from the tracking control unit 110, and the optical head 107 is gradually moved in the radial direction along with the progress of reproduction. The recording signal processing unit 118 adds an error correction code or the like to the recording data input at the time of recording, and outputs it to the LD driving unit 119 as an encoded recording signal. When the system control unit 121 sets the LD driving unit 119 to the recording mode by the control signal T4, the LD driving circuit 119 modulates the driving current applied to the semiconductor laser 101 according to the recording signal. As a result, the intensity of the light spot irradiated onto the optical disc 100 changes according to the recording signal, and a recording pit is formed. On the other hand, at the time of reproduction, the LD drive unit 119 is set to the reproduction mode by the control signal T4, and the drive current is controlled so that the semiconductor laser 101 emits light with a constant intensity. As a result, the recording pits and pre-pits on the recording track can be detected.

  Next, the single spiral land groove format will be described. In a conventional land / groove recording type optical disk, the groove portions are continuously connected on the disk, and therefore the inter-groove portions are also continuously connected on the disk. FIG. 12 is a diagram showing an optical disc having a format in which a recording track in a conventional groove portion and a recording track in the groove portion are alternately connected to form one recording spiral. As shown in FIG. 12, an optical disc having a format in which recording tracks in the groove and recording tracks in the groove are alternately connected to form one recording spiral is disclosed in Patent Document 2 and the like. An optical disc having such a format is referred to herein as a single spiral / land groove format: SS-L / G format.

  In order to apply tracking servo to an SS-L / G format disk, the connection point where the recording track of the groove portion and the recording track of the groove portion are alternately connected is accurately detected, and the tracking servo is then detected in the groove portion. It is necessary to switch the servo polarity to be applied to the recording track or to the recording track between the grooves.

  Now, a description will be given of how to insert an identification signal prepit in an optical disk medium driven by the land / groove recording type optical disk apparatus described above. In the land / groove recording system, there are three known methods for inserting the identification signal prepit as shown in FIG. In the method shown in FIG. 13A, which is also called a land / groove independent address system, a unique sector address is assigned to each of the land track sector and the groove track sector. If the pit width representing the identification signal is the same as the groove width, the identification signal pre-pits of the sectors of adjacent tracks are connected and the signal cannot be detected. Therefore, the pit width of the identification signal is narrower than the groove width. , About half of the groove width. However, at this time, grooves and prepits having different widths cannot be continuously formed unless the beam diameters of the beam for cutting the prepit and the beam for cutting the groove are changed in the optical disk master production process. Therefore, the master disk must be cut using two beams, a groove cutting beam and a pit cutting beam. If the centers of the two beams are deviated, a tracking offset occurs during the reproduction of the identification signal prepit and during the recording / reproduction of the information recording signal, which deteriorates the quality of the reproduced data. Specifically, the error rate increases due to the tracking error, leading to a decrease in data reliability. For this reason, high accuracy is required for the alignment of the two beams, which causes a cost increase in the disc master production process.

  Considering such circumstances, the method shown in FIG. 13B or FIG. 13C in which grooves and pits can be cut with a single beam is desirable from the viewpoint of accuracy of disk manufacture and cost. FIGS. 13B and 13C show a method of adding an identification signal prepit that can make the groove width and the prepit width substantially equal.

  FIG. 13B shows a conventional optical disk recorded in Patent Document 1, which is also called a land / groove shared address system. In this system, identification signal prepits are arranged near the center of a pair of adjacent groove tracks and land tracks, and the same identification signal prepits are shared by both tracks.

  FIG. 13C shows a time division L / G independent address system. An independent address is added to each of the land track and the groove track, but the prepits of the identification signals are shifted in the direction parallel to the tracks so that the prepits of the identification signal are not adjacent to each other in adjacent tracks. It is. An example is disclosed in Patent Document 3.

  When applying the sector address assignment method applied to the conventional land / groove disk to the optical disk having the SS-L / G format shown in FIG. 12 and described, the following problems arise. For example, consider a case in which the identification signal prepit is shifted from the center of the groove by a certain amount (such as ¼ of the track pitch) in the radial direction by the method shown in FIG. 13B as described in Patent Document 1. . In the SS-L / G format optical disk, the recording track in the groove and the recording track in the groove are connected once per recording track. FIG. 14 shows an arrangement diagram of recording tracks on the disk before and after the connection point in this case. In the recording sector, an identification signal pre-pit is added to the front of the recording track in the groove, and the identification signal pre-pit is displaced from the groove center in the radial direction, for example, by 1/2 of the groove width from the outer periphery side. Will be placed. Although nothing is recorded at the position of the identification signal prepit of the recording track in the groove portion, the identification signal of the adjacent track (recording track in the groove portion) on the inner peripheral side protrudes. A light spot scans the recording track in order to record / reproduce information. The identification signal of the recording track in the groove is detected because the outer half of the light spot is modulated by the identification signal preformatted. During scanning of the recording track in the groove portion, the identification signal of the track in the groove portion on the inner circumference side is detected by modulating the inner half portion of the light spot. Therefore, the same identification signal is read by the recording track in the groove portion and the recording track in the groove portion adjacent to the outer peripheral side thereof. Since the system controller 121 recognizes whether the optical disk apparatus scans the groove portion or the inter-groove portion with the light spot (that is, the polarity of tracking), the recording sector is identified by the output of the address reproducing unit 114. This can be performed by the address calculation unit 115 by using address information obtained from a certain identification signal and a control signal T2 coming from the system control unit.

  As shown in the figure, the address of the recording sector of the recording track in the groove next to a certain connection point is assumed to be #n. Assuming that the number of sectors of one recording track is N, when the recording track in the groove on the disk is traced once, the address of the sector of the recording track in the groove before the next connection point is # (n + N-1). . This sector is connected to the sector of the recording track in the groove portion through the connection point. Since the address of the sector in the groove portion is the same as the sector of the groove portion in contact with the inner peripheral side, Return. Similarly, when the recording track in the groove portion is traced once on the disk, the address becomes # (n + N-1) in the recording sector in the groove portion before the next connection point. This sector is connected to the sector of sector address # (n + N) of the recording track in the groove through a connection point. In the same manner, N recording sectors in the groove and N recording sectors in the groove are continuously connected alternately. FIG. 15 shows the change of the recording sector address when the recording spiral is traced in this way.

  In conventional optical discs such as compact discs and magneto-optical discs, only one of the grooves or the inter-groove portions is used as a recording track, so the information track generally forms one spiral, and the recordings are arranged on the spiral. Address numbers are assigned to the sectors in order. When accessing a sector, the relationship between the address number and the order before and after the sector was very easy to understand. On the other hand, when the conventional technique is applied to the SS-L / G recording disk, the sector address value and the position on the recording spiral do not change monotonously as shown in FIG. Hateful. The read recording sector address is temporarily replaced with an address value representing the sector order in consideration of the tracking polarity recognized by the apparatus, and the arrangement order on the recording spiral is known for the first time. Whenever a specific sector of such an optical disk is to be accessed on the optical disk device, such an address calculation is required. When performing random access, complicated address calculation is required every time, and the burden on the apparatus is large.

  This burden becomes more prominent in the format adopted for the high-density optical disc. The optical disk surface is divided into a plurality of zones, and the so-called ZCAV (Zoned Constant Angular Velocity) format or ZCLV (Zoned Constant Linear Velocity) format is used to increase the number of recording sectors constituting one recording track in the outer peripheral zone. In the disk, the number N of sectors per track shown in FIG. 14 and FIG. 15 changes as the zone moves depending on the radial position on the disk, so the recording spiral is determined from the recording sector address and the tracking polarity as described above. The calculation for calculating the addresses corresponding to the above arrangement order is further complicated. For example, it is assumed that one zone is configured by collecting pairs of tracks in the groove portion and tracks in the groove portion that share identification information. This is because the identification information portion is not arranged across the zone boundary where the number of sectors per track changes. At this time, there are two sectors each having the same address. Since the number of sectors included in one track increases in the outer peripheral zone, the period of appearance of sectors having the same sector address becomes longer when following the recording spiral.

  Here, it is also conceivable to apply the L / G independent address system as shown in FIG. Since no information is disclosed about how to give an address in Patent Document 3 of the conventional example, a specific implementation method is unknown, but as an example, addresses that are continuously independent from each other in the groove part and the inter-groove part. It is easily conceivable to give. At this time, the relationship between the position on the recording spiral and the recording sector address is the same as that of the land / groove shared address method shown in FIG. The change is set as shown in FIG. 15, for example. The zone format is schematically as shown in FIG.

  However, unlike the case of FIG. 13B, it is not necessary to discriminate the land sector / groove sector from the tracking polarity on the drive device side, but it can be discriminated by the content of the identification signal reproduced from the disk surface. Although it can be said that there has been some progress, it has not yet solved the above-mentioned problem of complicated address calculation.

  Next, I will point out problems related to the servo system. In the SS-L / G system, recording is performed on both the land and the groove, so that the track density is high. For this reason, when the tracking offset is increased, the reproduction signal quality deteriorates due to crosstalk from the adjacent track, for example, the error rate increases due to an increase in jitter, or the cross erase that erases a part of the adjacent track occurs during recording. To do. The error signal causing the tracking offset is generated in combination by the optical head system, the track arrangement on the disk, and the servo circuit system, and therefore generally has different sizes for the land track and the groove track. In order to eliminate crosstalk and cross erase, it is necessary to perform offset compensation of different sizes for each land and groove track. In the conventional land / groove method, that is, a method in which only one groove track and one land track constitute each recording spiral, each track is continuously tracked for offset compensation according to each land / groove track. During the process, it took some time, and after the adjustment, the compensation amount could be maintained, so that the offset compensation could be easily performed. However, in the SS-L / G disc, since the switching of the tracking polarity between the land track and the groove track is performed at a high frequency of once per rotation of the disc, it is necessary to accurately perform the tracking offset compensation in a short time. .

  In the conventional method of inserting the identification signal into the land / groove recording described above, such offset compensation is not taken into consideration. For example, in the case of the land / groove shared address system shown in FIG. 13 (b), since the pit is only on one side during reproduction of the identification signal, the tracking offset is increasing. Further, in the case of the L / G independent address system as shown in FIG. 13C, the same applies to the case shown in FIG. 13B, but it is difficult to detect the tracking offset.

  Conventionally, a so-called composite track wobbling method disclosed in Patent Document 4 or the like is known as a typical method for correcting such a tracking offset generated in a push-pull tracking servo system. In this method, a header area consisting of a pit array shifted to the left and right with respect to a track center arranged at a predetermined location and a data storage area consisting of a pregroove having a predetermined depth are alternately formed in advance along the track. Reproducing left and right wobbling pits by using the symmetry of the signal amplitude when playing pits wobbling in the header area while tracking servo control is continuously performed using the push-pull method. By controlling the amplitude to be equal, the tracking offset in the low band is corrected.

  The use of such a conventional technique in inserting a header identification signal is more effective than the respective systems shown in FIG.

  Since the conventional land / groove recording optical disk medium and optical disk apparatus are configured as described above, calculation of the recording sector address becomes complicated when the identification signal addition method is applied to the single spiral land / groove recording format as it is. There was a problem.

  In addition, the single spiral land groove recording format has a problem that it is difficult to detect the tracking offset while it is necessary to perform the tracking offset compensation accurately in a short time.

  Further, in the single spiral land / groove recording format, a method capable of easily detecting the connection point between the land track and the groove track is required.

  The present invention has been made to solve the above-mentioned problems. In an optical disc in which recording tracks in the groove and recording tracks in the groove are alternately connected to form one recording spiral, An object of the present invention is to obtain an optical disk medium in which addresses correspond to one-to-one recording sectors.

  According to the present invention, in the optical disk in which the recording tracks in the groove portions and the recording tracks in the groove portions are alternately connected to form one recording spiral, the sector addresses of all the recording sectors are arranged in the order arranged on the recording spiral. The object is to obtain a numbered optical disc medium.

  An optical disk medium capable of accurately performing tracking offset compensation in a short time in an optical disk in which recording tracks in grooves and recording tracks in grooves are alternately connected to form one recording spiral. The purpose is to obtain.

  Furthermore, in an optical disc in which recording tracks in the groove portion and recording tracks in the groove portion are alternately connected to form one recording spiral, an optical disc medium capable of easily detecting the connection point between the land track and the groove track is provided. The purpose is to obtain.

  Still another object of the present invention is to obtain a method for reproducing the above optical disk medium.

The present invention
Groove track and inter-groove track form a recording area,
Sectors radially aligned with each other of adjacent groove tracks and inter-groove tracks share one identification information area,
The identification information indicating the address of each sector is represented by being displaced in the radial direction from the groove center on the disk surface,
A plurality of pieces of identification information are continuously arranged in the track direction in one identification information area,
One identification information area is divided in the track direction, and a portion of identification information indicating the address of the groove sector and a portion of identification information indicating the address of the groove sector are separately provided,
The recording area is divided into multiple zones,
When an integer value equal to or larger than the number of recording sectors constituting one recording track in the outermost circumferential zone is J, the difference between the address values of the radially aligned sectors of adjacent tracks in each zone is The present invention provides an optical disk medium characterized by J.

  According to the present invention, when the address information of the target sector cannot be read due to a read error, it can be complemented by referring to the address information of the sector of the adjacent track. It is also possible to always read both addresses and increase the degree of multiplexing of the address information, so that the read reliability of the address information can be improved. Further, the address management of the connection point between the land track and the groove track can be simplified with the ZCAV formatter and the ZCLV format.

  Embodiments of the present invention will be specifically described below with reference to the drawings.

Embodiment 1 FIG.
In the following embodiments, description will be made centering on the identification information portion of an optical disk having a single spiral land / groove (SS-L / G) recording format. In an SS-L / G format disc, there are two types of recording tracks, groove portions (grooves, concave portions) and groove portions (lands, convex portions), and the two recording tracks are alternately connected to form one recording spiral. The structure is formed. FIG. 1 is a schematic diagram for explaining the arrangement of identification information prepits and their address values in a recording sector of an optical disk medium according to Embodiment 1 of the present invention. As shown in the figure, the recording sector is composed of an information recording section capable of recording identification information section user data in which prepits are embossed. The identification information part is displaced from the groove center to the outer periphery of the disk by ½ of the groove width. That is, the identification information center is located on the boundary line between the groove track and the inter-groove track. This identification information includes four PIDs (Physical IDs). Further, in the identification information, as used in a conventional optical disk, a VFO (Variable Frequency Oscillator) used by the disk drive device to generate a reproduction clock frequency, an AM (byte synchronization probability at the time of address reproduction) ( Address Mark) and the like. Here, in order to explain the address values, these are omitted hereinafter. The first two PIDs contain the address value of the following groove sector, and the latter two PIDs contain the address value of the following groove sector.

  The identification information arrangement of the groove / inter-groove connection portion will be described. FIG. 2 is a schematic diagram for explaining the arrangement of identification information prepits and their address values in the recording sector in the vicinity of the groove / inter-groove connection portion of the optical disk medium according to the first embodiment of the present invention. As shown in the figure, the identification information part is located in front of the information recording part in the recording sector and has four PIDs, as in the parts other than the connection part. Further, each PID is displaced from the groove center to the outer periphery of the disk by ½ of the groove width.

  A method for recognizing the identification information portion of the drive device for the medium and the connecting portion between the groove / inter-groove will be described. Assume that the light spot from the apparatus is scanning the recording sector of the groove track. When a light spot enters the next recording sector identification information section, the identification information section is displaced to the outer circumference by a half of the groove width with respect to the groove center. Is detected. In other words, the tracking error signal of the apparatus detects this identification information part by utilizing that the tracking is shifted to the inner peripheral side while the light spot passes through the identification information part. Since the identification information part is located at the head of each sector and is read periodically, masking is performed with a detection window or the like, so that the identification information part can be reliably captured.

  When scanning the recording sector of the inter-groove track, the identification information portion is displaced to the inner peripheral side by ½ of the groove width, so that tracking is performed on the outer peripheral side as opposed to scanning the groove portion. The presence of the identification information part is detected from the tracking error signal indicating that the deviation is present. Since the tracking correction has a frequency band lower than the tracking error signal, the light spot does not move. In an actual apparatus, while scanning the identification information portion, a process such as applying a mask is performed so as not to perform tracking correction.

  Below, the detection method of the connection part of a groove part / inter-groove part is described. When the recording track is scanned, the groove / inter-groove connection portion appears only once per track. Now, consider the case of switching from the groove portion to the groove portion. The identification information portion of the first sector in the inter-groove portion is displaced from the center of the inter-groove portion to the inner periphery of the disk by ½ of the groove width. Since the previous sector is a groove, as described above, it should have been displaced to the outer circumference by ½ of the groove width. As a result, the recording sector including the identification information portion can be recognized as a connection portion between the grooves / inter-grooves. That is, when scanning the groove portion, the identification information is displaced to the outer periphery, but when it is displaced to the inner periphery, it is known that the groove portion has been entered at that time. In addition, when scanning the inter-groove portion, the identification information should have been displaced to the inner periphery, but if it is displaced to the outer periphery, it is known that the groove portion has been entered at that time. In this way, the groove / inter-groove connection point can be detected according to the direction of the tracking error signal in the identification information section.

  Next, a method for adding the PID address value in the identification information will be described. The address of the groove sector is added to the previous two PIDs 1 and 2 among the PIDs in the identification information that is arranged to be displaced from the groove center to the outer periphery by ½ of the groove width immediately before the sector information recording unit. Further, the address of the inter-groove sector is the last two of the PIDs in the identification information that is arranged just before the information recording part of the sector and is displaced from the inter-groove center to the inner peripheral side by ½ of the groove width. It is added to PID3 and 4.

  As shown in FIG. 1, when the address of a recording sector (groove in this figure) is #m (integer) and the number of sectors constituting one track is N (integer), the track from the sector of address #m is tracked. Is the sector address # (m + N). In the case of a further round, the address value is linear regardless of the physical shape of the sector (groove portion or inter-groove portion) alternately with # (m + 2N), thereafter # (m + 3N), # (m + 4N), and the groove portion and inter-groove portion. To change.

  At the groove / inter-groove connection point, as shown in FIG. 2, when the address of a certain recording sector (groove in this figure) is #n (integer) and the number of sectors in one track is #N (integer) The sector address that makes a round of the track from the sector of address #n is # (n + N). In the case of a further round, # (n + 2N), thereafter # (n + 3N), # (n + 4N), and the physical shape of the sector are alternately changed between the groove portion and the inter-groove portion, but the address value changes linearly. .

  This is illustrated in FIG. FIG. 3 is a diagram showing the relationship between the position on the recording spiral and the recording sector address of the optical disk medium according to Embodiment 1 of the present invention. Regardless of the tracking polarity, that is, whether the track is a groove or a groove, a one-to-one address value is obtained.

  In a conventional optical disk apparatus that drives a land / groove optical disk medium, there are two types of corresponding areas, a groove and an inter-groove, for one physical address. In other words, conventionally, for example, even one address value such as address 100 of a groove and address 100 of an inter-groove portion has shown two regions using a combination of types (groove portions or inter-groove portions).

  On the other hand, in the present invention, when creating a control program, the specific area can be accessed only with the address value without being aware of the groove portion or the groove portion.

  In order to specify an address value by the apparatus, for example, there is a method of specifying an address value using PIDs 1 and 2 of the identification information part while scanning a groove. This is because even if one of the two PIDs fails to be read for some reason, the address value can be specified by using the other PID.

  As another method, when the number N of sectors per track in the zone being accessed is known, the address value can be specified using PID 1, 2, 3, 4. In this case, more reliable address specification can be performed. That is, for example, the PIDs 1, 2, 3, and 4 of the identification information portion immediately before the groove sector of the address value p should be p, p, p + N, and p + N. Therefore, by comparing (majority decision) of PIDs 1, 2, 3, and 4 that can be actually read, address specification can be performed based on the four PIDs.

  Or, the PIDs 1, 2, 3, and 4 that could actually be read are corrected so that N is subtracted from PIDs 3, 4, and then the four parties are judged by simple majority logic. A highly specific address can be specified.

  In the embodiment described above, four PIDs are put in one identification information section. However, for example, six or eight pieces of PID information can be put, multiplexing can be increased, and necessary reliability can be secured. Needless to say.

  Further, although not shown, as a more basic form of the embodiment, a form without multiplexing such as having only PID1 and PID3 is naturally conceivable.

  In the first embodiment, in the identification information portion, the address information portions of different sectors (sectors of adjacent tracks aligned in the radial direction) are continuous, so that synchronization pull-in for reproduction is performed in each identification information portion. This has the advantage that it only needs to be done once at the beginning and the format overhead is small.

  In addition, by assigning the address of the recording sector so as to monotonously increase or monotonously decrease in the order in which they are arranged on the recording spiral, regardless of whether the recording sector is a recording sector in a groove portion or a recording sector in a groove portion. The address calculation becomes very simple, and the control program of the apparatus and the access control circuit can be simplified.

  In FIG. 1, PID1 and PID2 in the first half of the identification information portion are assigned addresses of the sectors in the groove portion, and PID3 and PID4 in the second half are assigned addresses of the sectors in the groove portion adjacent to the outer periphery of the sector in the groove portion. However, the assignment method is not limited to this. PID1 and PID2 may indicate sectors in the groove portion, and PID3 and PID4 may indicate sectors in the groove portion. In short, it suffices if the identification information part arranged in a shared manner on the boundary between the groove part and the groove part contains all the address indications of the sectors sharing the identification information part.

Embodiment 2. FIG.
FIG. 4 is a schematic diagram for explaining the arrangement of identification number prepits and their address values in the recording sector of the optical disk medium according to the second embodiment of the present invention.

  In this embodiment, the identification signal consists of two parts, a front part and a rear part in the scanning direction, and the front part is displaced from the groove part to the outer peripheral side by ½ of the groove width. The rear part is displaced from the groove part to the inner peripheral side by ½ of the groove width.

  Next, a method for adding the address value of the identification signal will be described. The address of the groove is added to the identification signal immediately before the information recording unit, to the front identification signal that is displaced from the groove center to the outer circumference by ½ of the groove width. Further, the address of the groove part is the inner circumference side of the groove part from the groove center in the identification signal immediately before the information recording part of the recording track of the groove part on the outer peripheral side of the recording track in the groove part. Is added to the rear identification signal which is displaced. As a result, the address of the groove portion is added to the identification signal immediately before the information recording portion added to the rear portion identification signal that is displaced from the center of the groove portion to the outer peripheral side by 1/2 of the groove width. Become.

  This is because it is considered that the tracking offset generated when the disc master is cut is smaller when cutting the groove track and the groove address at the same time when cutting the recording track of the groove. In view of the tracking offset characteristics, when the recording track in the groove is cut (scanning while applying a light spot), the address of the groove is cut, and the recording track in the groove is cut (scanning without applying a light spot). If the tracking offset is sometimes smaller when cutting the address of the groove part, it may be cut separately.

  As shown in the figure, when an address of a recording sector (groove portion in this figure) is #m (integer), and the number of sectors constituting one track is N (integer), the track goes around from the sector of address #m. The sector address thus obtained is # (m + N). In the case of a further round, # (m + 2N), # (m + 3N), # (m + 4N), and the physical shape of the sector alternately change between the groove part and the groove part, but the address value changes linearly.

  Next, a description will be given of a method of adding an address at the connection portion between the land and the groove that are aligned in the radial direction of the disk once per disk. FIG. 5 is a schematic diagram for explaining the arrangement of the identification number prepits in the recording sector and the address values thereof at the connection point between the optical disk medium land and the groove according to the second embodiment. In the SS-L / G format disc, there is a connection point where the recording track in the groove portion and the recording track in the groove portion are connected to one another in the circumferential direction of the track and aligned in the radial direction. In the same manner as the arrangement of the identification signals other than the connection point, the identification signal is arranged so that the front part is displaced from the groove part to the outer peripheral side by 1/2 of the groove width. The rear part is displaced from the groove part to the inner peripheral side by ½ of the groove width. In addition to the addition of the connection point, the address of the groove is added to the front identification signal arranged so as to be displaced from the groove immediately before the information recording portion to the outer periphery by ½ of the groove width. In addition, the address of the inter-groove portion is added to a rear identification signal that is disposed by being displaced from the inter-groove portion immediately before the information recording portion to the outer peripheral side by ½ of the groove width.

  As shown in the figure, when the address of a certain recording sector (groove in this figure) is #n (integer), and the number of sectors in one track is N (integer), the track is circled from the sector of address #n. The sector address is # (n + N). In the case of a further round, # (n + 2N), thereafter # (n + 3N), # (n + 4N), and the physical shape of the sector are alternately changed between the groove portion and the inter-groove portion, but the address value changes linearly. . Also, when looking at the continuity before and after the connection point, the sector of the groove part is the identification signal of the first half that is displaced from the groove part to the outer peripheral side by ½ of the groove width, and the sector of the groove part is from the groove part. The address can be specified from the identification signal in the latter half that is displaced to the outer circumference by ½ of the groove width.

  The relationship between the position on the recording spiral of the optical disc medium according to the second embodiment and the recording sector address is as shown in FIG. 3, regardless of the tracking polarity, that is, whether the track is a groove or a groove, That is, a one-to-one address value is obtained.

  Next, an apparatus for recording / reproducing the optical disk medium will be described. FIG. 6 is a block diagram showing a configuration of an optical disc apparatus according to Embodiment 2 of the present invention. In FIG. 6, 100 is an optical disk, 101 is a semiconductor laser, 102 is a collimating lens, 103 is a half mirror, 104 is an objective lens, 105 is a photodetector, 106 is an actuator, 107 is an optical head, 108 is a differential amplifier, 109 is Polarity inversion unit, 110 tracking control unit, 111 addition amplifier, 112 waveform shaping unit, 113 reproduction signal processing unit, 114 address reproduction unit, 116 traverse control unit, 117 traverse motor, 118 recording signal processing The reference numeral 119 denotes a laser driving unit, and 120 denotes a driving unit. The above is basically the same as the conventional optical disk apparatus shown in FIG. .

  A configuration of a portion different from FIG. 11 will be described. Reference numeral 1 denotes an address extraction unit that receives a digital signal from the waveform shaping unit, a tracking error signal from the differential amplifier 108, and a control signal T1 from the system control unit, and outputs an address signal to the address reproduction unit 114. is there. 2 outputs control signals T1 to T4 to the address extraction unit 1, polarity inversion unit 109, tracking control unit 110, traverse control unit 115, LD drive unit and recording signal processing unit 118, and inputs an address signal from the address calculation unit 15. System control unit.

  The operation of the optical disk apparatus according to the second embodiment configured as described above will be described focusing on the address recognition method. Now, assume that the light spot is scanning the groove. At this time, the system control unit 2 outputs an L level signal corresponding to the groove portion to the control signal T1 indicating the polarity. The address extraction unit receives this control signal T1, and recognizes that the first half of the identification signal is the sector address of the next groove. The tracking error at this time indicates that the identification signal of the first half is shifted to the outer periphery of the disk by 1/2 of the groove width with respect to the groove, so that the tracking error signal is greatly shifted to the inner periphery. From this, it can be recognized that the identification mark read is correct.

  On the contrary, it is assumed that the light spot scans between the grooves. At this time, the system control unit 2 outputs an H level signal corresponding to the groove portion as a control signal T1 representing polarity. The address extraction unit receives this control signal T1, and recognizes that the latter half of the identification signal is the sector address of the next inter-groove portion. The tracking error at this time indicates that the identification signal in the latter half is shifted to the outer periphery of the disk by ½ of the groove width with respect to the inter-groove portion, so that the tracking error signal is greatly shifted to the inner periphery. This also confirms that the read identification mark is correct.

  Further, as shown in the first embodiment, in addition to using two PIDs, it is possible to compare using four PIDs, that is, using all PIDs 1, 2, 3, and 4 that can be actually read. Needless to say. That is, for example, PID1, 2, 3, 4 in the identification information portion immediately before the address value p of the groove sector should be p, p, p + N, p + N. Therefore, the address can be specified based on the four PIDs by comparing with the PIDs 1, 2, 3, and 4 that can be actually read (majority decision) or by making a simple majority decision after applying correction by N. .

  The address data output from the address extracting unit has a one-to-one correspondence with the physical sector address, and the address of the recording sector is uniquely determined by the read address data regardless of the groove portion and the groove portion. Can be determined.

  As described above, the first address information part, which is a part of the identification signal, is arranged with a certain amount of displacement in one radial direction from the center of the groove part, and is the other part of the identification signal. The second address information part is disposed in the other radial direction from the center of the groove part and displaced by the same amount as the fixed amount, and the first address information part represents the address of the recording sector of the groove part, By expressing the address of the recording sector in the groove portion adjacent to the groove portion in the second address information portion, the address and the recording sector are obtained regardless of whether the address value obtained from the identification signal is the groove portion or the groove portion. Correspond to each other in a one-to-one manner, so that there are no two sectors having the same address such as k in the groove address (k is an integer) and k in the groove address as in the prior art. Sector address to groove It is possible to uniquely determine regardless the land part.

  As described in the first embodiment, the address of the recording sector is monotonically increased in the order in which the recording sector is arranged on the recording spiral regardless of whether the recording sector is a groove recording sector or a groove recording sector. In addition, since the address calculation is monotonously decreased, the address calculation becomes very simple, and the control program of the apparatus and the access control circuit can be simplified. Further, as described in the first embodiment, the addresses displayed on each PID in the identification information section are not limited to the illustrated combinations.

  Furthermore, as another function and effect, the track offset correction will be described. The tracking offset amount can be detected by providing a pair of track offset detection pits displaced by a certain amount from the track center to the left and right as used in the sample servo optical disk. When the light beam passes through the middle of the track offset detection pit pair, the reproduction signal amplitude of the detection pit pair becomes equal. When off-tracking on one side, the playback signal amplitude of the pit on one side increases and the playback signal amplitude of the pit on the other side decreases, so that the track offset amount of the light beam can be detected and corrected. The light beam can be controlled to pass through the center of the track. In the present invention, the same principle and effect can be incorporated into the single spiral land groove recording format.

  Assume that the light beam enters the identification signal area of the next groove recording sector from the information recording area in the specific groove recording sector. Since the head of the identification signal is shifted by ½ of the groove width on the outer periphery of the disk, a corresponding tracking error signal is output. After a while, since there is an identification signal shifted by ½ of the groove width on the inner circumference of the disk, a tracking error signal corresponding to it is output. If these two error signals are ideally detected with the same amplitude, the track center is scanned. Therefore, the servo can be controlled at the track center by using the repetition of the identification signal shifted to the inner periphery and the outer periphery.

Embodiment 3 FIG.
An optical disk recording medium according to Embodiment 3 will be described below. FIG. 7 is a schematic diagram for explaining the arrangement of identification number prepits and their address values in the recording sector of the optical disk medium according to Embodiment 3 of the present invention. The third embodiment is characterized in that identification signals are multiplexed. As shown in the figure, the identification signal is obtained by recording address information twice in each of the two identification signals (identification signal pairs) at the front and rear in the scanning direction shown in FIG. 4 of the second embodiment. is there. The front part of the identification signal pair is displaced from the groove part to the outer peripheral side by 1/2 of the groove width, and the rear part of the identification signal pair is displaced from the groove part to the inner peripheral side by 1/2 of the groove width. This is the same as in the second embodiment. Further, in the present embodiment, the data is recorded in a duplex manner, but a triple or quadruple configuration may be used.

  By adopting such a configuration, since the address information is multiplexed and recorded, the read error rate of the address information in the identification signal is reduced.

Embodiment 4 FIG.
The optical disk recording medium according to the fourth embodiment will be described below. FIG. 8 is a schematic diagram for explaining the arrangement of identification number prepits and their address values in the recording sector of the optical disk medium according to the fourth embodiment of the present invention. The fourth embodiment is characterized in that identification signals are multiplexed. As shown in the figure, the identification signal is a double recording of two identification signals (identification signal pairs) at the front and rear in the scanning direction shown in FIG. 4 of the second embodiment. The front part of each identification signal pair is displaced from the groove part to the outer peripheral side by 1/2 of the groove width, and the rear part of each identification signal pair is displaced from the groove part to the inner peripheral side by 1/2 of the groove width. Arranging is the same as in the second embodiment. Further, in the present embodiment, the data is recorded in a duplex manner, but a triple or quadruple configuration may be used.

  By adopting such a configuration, since the address information is multiplexed and recorded, the read error rate of the address information in the identification signal is reduced. The difference from the third embodiment is that the address information is improved because the addresses of the groove portions and the inter-groove portions are multiplexed and recorded at separate locations. However, since each address information section has to start from the synchronization pull-in of the reproduction signal, there is a disadvantage that the overhead on the format is large.

  As another function and effect, it goes without saying that the same principle and effect used in the sample servo type optical disc can be incorporated into the single spiral land groove recording format as shown in the second embodiment. Yes. At this time, by recording a plurality of sets of the first address information portion and the second address information in the identification signal alternately, the tracking error detection time can be extended and the accuracy can be improved. The identification signal can be used to more easily correct the servo tracking correction.

Embodiment 5 FIG.
In the second embodiment, when one recording track is composed of N recording sectors, the address is set so that the address of the recording sector is increased by N when the recording spiral is followed by one track. . However, if the position on the recording spiral and the recording sector address are given so as to monotonously increase or monotonously decrease, the address calculation is considerably simplified. When it is easier to create an access system as a system by skipping the recording sector address in the middle of the system configuration, it is possible to assign a recording sector address as shown in FIG. FIG. 10 shows the relationship between the position on the recording spiral and the recording sector address.

  The fifth embodiment shows an example in which the address is set so that the address of the recording sector is increased by (N + k) when the recording spiral is followed by one track. When two tracks are traced on the recording spiral, the address of the recording sector increases by (2N + 2k). For example, (N + k) is set to a constant value equal to or greater than the number of recording sectors constituting one recording track in the outermost zone, and the change in the number N of recording sectors per recording track in each zone. It is also possible to keep the difference in sector address between adjacent tracks constant by changing k in the opposite direction. Since the light spot always reads the address information of one adjacent sector during tracking the track in the groove part and tracking the track in the groove part, if such a mechanism is incorporated, the address of the own sector will be read. When information cannot be read due to an error, it can be referred to and supplemented. It can also be used to constantly read both addresses and increase the degree of multiplexing of address information.

  In the ZCAV format and the ZCLV format, the number of recording sectors per track differs depending on the zone on the disk. However, if the length of one track varies depending on the zone, the address management of the connection point between the land track and the groove track becomes complicated. At this time, the address management can be simplified by adopting the method shown in the fifth embodiment.

  Even in this case, the address and the recording sector have a one-to-one correspondence regardless of whether the address value obtained from the identification signal is a groove portion or an inter-groove portion. The fact that there are no two address sectors and the sector address can be uniquely determined regardless of the groove part and the groove part is not lost at all.

Embodiment 6 FIG.
Note that recording / reproduction of the optical disk recording medium of Embodiment 1 can also be performed by using an apparatus having a block configuration similar to that shown in FIG. Further, the first embodiment can be modified in the same manner as described in the fifth embodiment.

FIG. 5 is a schematic diagram for explaining the arrangement of identification number prepits and their address values in the recording sector of the optical disc medium according to the first embodiment of the present invention. FIG. 5 is a schematic diagram for explaining the arrangement of identification number prepits in a recording sector and the address values thereof at the connection point between the optical disk medium land and groove according to the first embodiment of the present invention. It is a figure showing the relationship between the position on the recording spiral of the optical disk medium which is Embodiment 1 of this invention, and a recording sector address. It is a schematic diagram for demonstrating arrangement | positioning of the identification number prepit in the recording sector of the optical disk medium which is Embodiment 2 of this invention, and its address value. FIG. 6 is a schematic diagram for explaining the arrangement of identification number prepits in a recording sector and their address values at a connection point between an optical disk medium land and a groove according to a second embodiment of the present invention. It is a block diagram which shows the structure of the optical disk apparatus which is Embodiment 2 of this invention. It is a schematic diagram for demonstrating arrangement | positioning of the identification number prepit in the recording sector of the optical disk medium which is Embodiment 3 of this invention, and its address value. It is a schematic diagram for demonstrating arrangement | positioning of the identification number prepit in the recording sector of the optical disk medium which is Embodiment 4 of this invention, and its address value. It is a schematic diagram for demonstrating arrangement | positioning of the identification number prepit in the recording sector of the optical disk medium which is Embodiment 5 of this invention, and its address value. It is a figure showing the relationship between the position on the recording spiral of the optical disk medium which is Embodiment 5 of this invention, and a recording sector address. It is a block diagram which shows the structure of the conventional optical disk apparatus. It is a figure showing the optical disk which has the format which connected the recording track of the conventional groove part, and the recording track of the said groove part alternately, and formed one recording spiral. It is a figure which shows how to insert the identification signal prepit in the conventional land / groove recording system. FIG. 10 is a schematic diagram for explaining the arrangement of identification number prepits in a recording sector and the address value thereof at a connection point between a conventional optical disk medium land and groove. It is a figure showing the relationship between the position on the recording spiral of a conventional optical disk medium, and a recording sector address. It is a figure showing the relationship between the position on the recording spiral in a zone format, and a recording sector address.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Address extraction part, 2 System control part, 100 Optical disk, 101 Semiconductor laser, 102 Collimate lens, 103 Half mirror, 104 Objective lens, 105 Photo detector, 106 Actuator, 107 Optical head, 108 Differential amplifier, 109 Polarity inversion part 110 tracking control unit, 111 addition amplifier, 112 waveform shaping unit, 13 reproduction signal processing unit, 114 address reproduction unit, 115 address calculation unit, 116 traverse control unit, 117 traverse motor, 118 recording signal processing unit, 119 laser driving unit , 120 drive unit, 121 system control unit.

Claims (2)

Groove track and inter-groove track form a recording area,
Sectors radially aligned with each other of adjacent groove tracks and inter-groove tracks share one identification information area,
The identification information indicating the address of each sector is represented by being displaced in the radial direction from the groove center on the disk surface,
A plurality of pieces of identification information are continuously arranged in the track direction in one identification information area,
One identification information area is divided in the track direction, and a portion of identification information indicating the address of the groove sector and a portion of identification information indicating the address of the groove sector are separately provided,
The recording area is divided into multiple zones,
When an integer value equal to or larger than the number of recording sectors constituting one recording track in the outermost circumferential zone is J, the difference between the address values of the radially aligned sectors of adjacent tracks in each zone is An optical disc medium characterized by J. A method for reproducing an optical disk medium according to claim 1, comprising:
An optical disc medium characterized by identifying an address of a sector being scanned using identification information of an adjacent track in an identification information area and a known integer value J indicating a difference in sector address value between adjacent tracks Playback method.

Images