JP3551074B2 - Optical disc, optical disc recording / reproducing apparatus, optical disc recording / reproducing method - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
In particular, the present invention relates to an optical disk and an optical disk recording / reproduction capable of recording or reproducing data at high density on both lands and grooves by multiplexing a multiplexing mark corresponding to address information on a wobbled pre-groove. The present invention relates to an apparatus and an optical disk recording / reproducing method.
[0002]
[Prior art]
In order to record data on a disc, it is necessary to record address information in advance, for example, in a groove so that data can be recorded from a predetermined position (FIG. 6). In some cases, this address information is wobbled and recorded on a track corresponding to frequency-modulated address information such as CD-R ATIP (Absolute Time In Pregroove).
[0003]
That is, as shown in FIG. 6, a track for recording data is formed as a pre-groove (described as a groove), and the side wall of the pre-groove is wobbled (meandering) in accordance with the frequency-modulated address information. . In this way, the address information can be read from the wobbling information, and the data can be recorded at a desired position. In FIG. 6, ID indicates a dedicated area of the address pit, m-1 and m + 1 indicate groove tracks, and m indicates a land track.
[0004]
[Problems to be solved by the invention]
However, in the case where address information is recorded by wobbling by frequency modulation in this way, when data is recorded on the groove tracks m-1, m + 1, it is possible to read the address information accurately, and Although data can be recorded at the position, the wobbling signals of the adjacent left and right groove tracks m-1 and m + 1 are combined in the land track m, and there is a problem that it becomes difficult to correctly reproduce the wobbling signal. As a result, there has been a problem that the rotation control information and the address information cannot be read, and it is difficult to record and record data on the land.
[0005]
As one method for solving this problem, Japanese Patent Application Laid-Open No. 9-231580 discloses a method in which a synchronization signal serving as a reference of a rotation control signal is recorded by wobbling, and address information is formed by prepits. The information recording area is divided into a plurality of zones in the radial direction, and the groove wobbles in the radial direction at a predetermined frequency according to each zone in each of the plurality of zones when the recording medium is rotated at a constant angular velocity. By setting the spatial frequency of the wobble to be substantially constant in each zone, a single frequency wobble can be correctly reproduced even on a land track. The address information can be obtained from both the land and the groove if the address information is previously carved as a prepit on the boundary between the land and the groove.
[0006]
However, this method requires a dedicated area ID of an address pit for recording address information, as shown conceptually in the form of a disk with reference to FIG. 7, and furthermore, since the recording data is divided here, It is necessary to insert a VFO (Variable Frequency Oscillator) after the address pit area (at the head of the data) so that the PLL for data reading is easily synchronized, and the actual recording capacity of the disk is reduced. .
[0007]
Therefore, in a disk that records data on both lands and grooves, it is necessary to physically separate the address area and the data area, and there is a problem that it is difficult to perform high-density recording.
[0008]
The present invention has been made in view of such a situation, and is an optical disc in which a track for recording and reproducing data is wobbled and formed, wherein the track corresponds to a synchronization signal of a fixed cycle. A wobble is formed, and a multiplex mark corresponding to address information at a frequency higher than the frequency of the wobble is superposed and formed in synchronization with one cycle of the wobble, so that both the land and the groove are formed. It is an object of the present invention to provide an optical disk that can record data at high density and can also record data in an address area by using both an address area and a data area.
[0009]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides an optical disk, an optical disk recording / reproducing apparatus, and an optical disk recording / reproducing method having the following configurations (1) to (4) .
(1) An optical disc in which tracks for recording and reproducing data are formed by wobble displacement at a constant frequency in a direction between guide grooves ,
The said guide groove, the wobble displacement position synchronized position, multiplexing marks at a frequency higher than the frequency, and corresponding to one address information for one wobble period of the wobble is, the width of the guide groove optical disc but which is characterized in that it is formed synchronously displaced to be constant, on both side walls of the guide groove.
(2) An optical disk in which tracks for recording and reproducing data are formed by wobble displacement at a constant frequency in a direction between guide grooves,
The said guide groove, at a position that is synchronized with the wobble displacement position, multiplexing marks at a frequency higher than the frequency, and corresponding to one address information for one wobble period of the wobble is, both sides of the guide groove The width of the guide groove corresponding to the side wall position where the multiplex mark is formed is displaced on one of the side walls of the wall, and the width of the guide groove corresponding to the side wall position where the multiplex mark is not formed is the guide. An optical disc having a width at least as large as the width of the groove .
(3) An optical disk recording / reproducing apparatus for recording / reproducing data on / from the optical disk according to claim 1 or 2,
Recording / reproducing means for recording / reproducing data on / from the optical disc;
Multiplex mark detection means for detecting the multiplex mark from the reproduction output of the recording / reproduction means,
Wobble detecting means for detecting the wobble from the reproduction output;
An optical disc recording / reproducing apparatus comprising: an address information reading unit that reads the address information using the synchronization signal detected from the detected multiplex mark and the wobble .
(4) In the optical disk recording / reproducing method for recording / reproducing data on / from the optical disk according to claim 1 or 2,
Detecting the multiplexed mark and the wobble from a reproduction output obtained by reproducing the optical disc,
An optical disk recording / reproducing method, wherein the address information is read using the synchronization signal detected from the detected multiplex mark and the wobble .
[0010]
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The optical disk of the present invention is an optical disk 1 in which tracks m-1, m, and m + 1 for recording and reproducing data are wobbled as shown in FIGS.
In the track, a wobble (synchronization signal wobble) 5 is formed corresponding to a synchronization signal having a predetermined period, and a multiplex mark 4 corresponding to address information at a frequency higher than the frequency of the wobble 5 is formed in one period of the wobble 5. An optical disc characterized by being formed in a superimposed manner in synchronization.
As shown in FIGS. 5 and 8, the optical disk recording / reproducing apparatus of the present invention is an optical disk recording / reproducing apparatus for recording / reproducing data on / from the optical disk 1 of the present invention.
A recording / reproducing means (optical head) 20a for recording / reproducing data on / from the optical disc 1,
Multiplex mark detection means (multiplex mark detection circuit) 20c for detecting the multiplex mark (FIG. 8A) from the reproduction output (reproduction RF signal) of the recording / reproduction means 20a;
Wobble detecting means (synchronous signal detecting circuit) 20d for detecting the wobble (FIG. 8B) from the reproduced output;
Address information reading means (consisting of a bi-phase demodulation circuit 20e and an address reading circuit 20f) for reading the address information using the synchronization signal detected from the detected multiplex mark and the wobble. An optical disk recording / reproducing apparatus characterized by the above-mentioned.
Further, the optical disk recording / reproducing method of the present invention is the optical disk recording / reproducing method of recording / reproducing data on / from the optical disk 1 of the present invention.
Detecting the multiplexed mark and the wobble signal from a reproduction output obtained by reproducing the optical disc,
An optical disk recording / reproducing method, wherein the address information is read using the synchronization signal detected from the detected multiplex mark and the wobble.
[0011]
Hereinafter, an optical disk, an optical disk recording / reproducing apparatus, and an optical disk recording / reproducing method of the present invention will be specifically described.
FIG. 1 shows a configuration example of the optical disk of the present invention. As shown in the figure, a pre-groove 2 described as a “guide groove (groove)” is formed on the optical disc 1 in a spiral shape from the inner periphery to the outer periphery in advance. The direction of the spiral may be formed from the outer periphery toward the inner periphery. As shown in a partially enlarged view in FIG. 1, the left and right side walls 21 and 2r of the pregroove 2 are wobbled at the frequency of the synchronization signal, and meander at a predetermined cycle (for example, 50 μm). I have. Multiplexing marks 4 are formed on the left and right side walls 21 and 2r, respectively. In the figure, reference numeral 3 denotes a land described as "between guide grooves (land)".
[0012]
A multiplex mark 4 is formed in advance in the pre-groove 2 corresponding to the address information, like a synchronization signal wobble on which the multiplex mark shown in FIG. 2 is superimposed. The multiplex mark 4 corresponding to the address information is formed by wobbling the pre-groove 2 at a cycle shorter than the wobbling cycle corresponding to the synchronization signal wobble 5. The multiplex mark 4 has a form that can be distinguished from a mark formed in the pre-groove 2 in accordance with data recording. In FIG. 3, the phases of the adjacent groove wobbles 2a and the land wobbles 3a substantially coincide with each other, and the width of the land 3 is formed to be substantially constant.
[0013]
FIG. 3 shows another configuration example of the optical disc of the present invention. A pre-groove 2 described as a “guide groove” is formed in advance on the optical disc 1 in a spiral manner from the inner circumference to the outer circumference in the same manner as shown in FIG. The direction of the spiral may be formed from the outer periphery toward the inner periphery. As shown in a partially enlarged manner, the left and right side walls 21 and 2r of the pre-groove 2 are wobbled at the frequency of the synchronization signal, and meander at a predetermined cycle (for example, 50 μm). The multiplex mark 4a is formed only on the left side wall 21. In the figure, reference numeral 3 denotes a land described as "between guide grooves (land)". As described above, the multiplex mark 4a may be formed on only one of the left and right side walls 21 and 2r.
[0014]
FIG. 4 is a block diagram showing a configuration example of an optical disk master manufacturing apparatus according to the present invention, and shows an example of a configuration of an optical disk master manufacturing apparatus 10 for manufacturing a master of the optical disk 1 shown in FIGS. Represents.
The optical disc master manufacturing apparatus 10 includes optical deflectors 10a and 10b, a mirror 10c, an objective lens 10d, a turntable (not shown), a spindle motor 10e, frequency dividers 10f and 10i, a low frequency wobbling signal generation circuit 10g, and an amplifier 10h. , 101, a biphase modulation circuit 10j, and a multiplexed mark pulse generation circuit 10k. D is a master coated with a photosensitive agent.
[0015]
The master exposure laser beam is deflected by the optical deflectors 10a and 10b, reflected by the mirror 10c, and rotatably mounted on a turntable (not shown) via the objective lens 10d. Irradiated on top. The turntable is rotated at a predetermined rotation speed by a spindle motor 10e. On the master D, a groove 2 having the mode shown in FIG. 1 is formed by a master exposure laser beam.
[0016]
The master clock having a predetermined frequency is frequency-divided by the frequency divider 10f, then generated as a continuous sine wave signal having a period of, for example, 3 μs by the low-frequency wobbling signal generation circuit 10g, and then fixed through the amplifier 10h. It is supplied to the optical deflector 10a as a synchronization wobble signal corresponding to the periodic synchronization signal. Thus, the optical deflector 10a outputs the laser light deflected by the synchronous wobbling signal.
[0017]
On the other hand, the master clock is supplied to the biphase modulation circuit 10j after being divided by the frequency divider 10i. Address data is supplied to the biphase modulation circuit 10j. A signal obtained by dividing the master clock and address data are supplied to the bi-phase modulation circuit 10j. The bi-phase modulation signal output from the bi-phase modulation circuit 10j is supplied to a multiplexing mark generating circuit 10k, where it is converted into a multiplexing mark pulse, and then, via an amplifier 101, multiplexing corresponding to a synchronization signal of a fixed period. The light is supplied to the optical deflector 10b as a mark signal. The multiplex mark signal is, for example, a pulse signal having one cycle of 100 ns. Thus, the optical deflector 10b outputs a master exposure laser beam deflected by the multiplexed mark pulse from the master exposure laser beam deflected by the low frequency wobbling signal. As a result, a laser beam for forming a pre-groove having address information is applied to the master D while being wobbled.
[0018]
FIG. 9 shows an embodiment of a circuit configuration for generating a multiplex mark signal and a synchronous wobble signal. The same components as those described above are denoted by the same reference numerals, and description thereof will be omitted. The clock and address data obtained by dividing the master clock by a predetermined dividing ratio are input to the bi-phase modulation circuit 10j, and the multiplex mark generation circuit 10k is operated in accordance with the bit data "1" after the bi-phase modulation. A DFF (D-type flip-flop) and an amplifier generate a positive / negative pulse of one master clock cycle length. On the other hand, the synchronization wobble signal is frequency-divided at a predetermined frequency division ratio, and is shaped into a sine wave by an LPF (Low Pass Filter) and an amplifier constituting the low frequency wobbling signal generation circuit 10g to generate a synchronization wobble signal. The multiplexed mark signal, which is a positive / negative pulse for a multiplexed mark, and a synchronous wobble signal, which is a sine wave signal for synchronous wobble, are generated by the optical deflectors 10a and 10b via the amplifiers 10h and 10l, respectively. Is input to
[0019]
In this manner, the exposed master D is developed, a stamper is created from the master D, and the optical disc 1 as a number of replicas is formed from the stamper. As a result, the optical disc 1 on which the pre-groove 2 having the above-mentioned synchronization signal and the multiplex mark is formed can be obtained.
[0020]
FIG. 5 shows an example of the configuration of an optical disk recording / reproducing apparatus of the present invention for recording or reproducing data on or from the optical disk 1 obtained as described above.
The data recording / reproducing device 20 includes an optical head 20a, a recording / reproducing circuit 20b, a multiplex mark detecting circuit 20c, a synchronizing signal detecting circuit 20d, a bi-phase demodulating circuit 20e, an address reading circuit 20f, a feed control circuit 20g, a feed motor 20h, a motor A control circuit 20i and a spindle motor 20j are provided. A reproduction signal processing system 20A to be described later includes a multiplex mark detection circuit 20c, a synchronization signal detection circuit 20d, a bi-phase demodulation circuit 20e, and an address reading circuit 20f.
[0021]
The optical head 20a irradiates the optical disc 1 with a recording laser beam to record data on the optical disc 1, and irradiates the recorded optical disc 1 with a reproduction laser beam to reproduce data from the reflected light. It is used when doing. The recording / reproducing circuit 20b modulates recording data by a predetermined method and outputs the modulated data to the optical head 20a. The recording / reproducing circuit 20b appropriately demodulates reproduced data output from the optical head 20a and outputs the demodulated data to an external device (not shown).
[0022]
The reproduction RF signal reproduced from the optical head 20a is supplied to a multiplex mark detection circuit 20c and a synchronization signal detection circuit 20d, where the multiplex mark (FIG. 8A) and the synchronization signal (FIG. 8A) are respectively obtained from the reproduction RF signal. (B)) is detected. The multiplexed mark and the synchronization signal thus detected are binarized and then demodulated by the bi-phase demodulation circuit 20e into a bi-phase signal (FIG. 8C). As shown in FIG. 8C, a multiplexing mark (FIG. 8A) has a low-frequency synchronization signal wobble (FIG. 8B) only in a portion corresponding to the logic "1" of the biphase modulated signal. And reproduced. As shown in FIGS. 8A and 8B, the multiplexing mark is multiplexed for one cycle of the synchronization signal corresponding to the address information. FIG. 8D shows data demodulated from the bi-phase signal.
[0023]
FIG. 10 shows another configuration example of the reproduction signal processing system 20A of the optical disk recording / reproduction device of the present invention. The same components as those described above are denoted by the same reference numerals, and description thereof will be omitted. A reproduction signal reproduced without including reproduction data from the optical head 20a is transmitted to a multiplex mark detection BPF (Band Pass Filter) 20c1 which is a multiplex mark detection circuit 20c and a synchronization signal detection BPF 20d1 which is a synchronization signal detection circuit 20d. A multiplex mark (FIG. 8 (A)) and a synchronization signal (FIG. 8 (B)) are respectively detected from the reproduced signal, and the multiplex mark and the synchronization signal detected in this way are converted to a binarization circuit 20A1, After being binarized by 20A2, the signal is demodulated into a bi-phase signal by a DFF 20A3, which is a bi-phase demodulation circuit 20e, and a bi-phase demodulation circuit 20e.
[0024]
The synchronization signal wobble detection circuit 20d detects a low-frequency signal of a fixed period from a signal reproduced and output by the optical head 20a. This synchronization signal is sent to the motor rotation control circuit 20j of the spindle motor 20i, and is used for CLV (Constant Linear Velocity) rotation control. The address information reading circuit 20f reads address information included in the multiplexed mark signal from the reproduced RF signal output from the optical head 20a, outputs the read result to a feed control circuit 20g, controls the feed motor 20h, and controls the feed motor 20h. The head 20a is fed. The synchronization signal wobble is reproduced in the same manner on the land and the groove, and a stable synchronization signal can always be obtained. Similarly, the multiplex mark can be reproduced on either a land or a groove, and the address can be read on either the land or the groove.
[0025]
As described above, according to the optical disc of the present invention, the address area and the data area can be used in common, and the rotation control information and the address information can be obtained on both the land and the groove.
[0026]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the optical disk, the optical disk recording / reproducing apparatus, and the optical disk recording / reproducing method of the present invention having the above-described configuration, data can be recorded at high density on both the land and the groove, and the address area is also used as the data area. It is possible to provide an optical disk capable of providing an optical disk recording / reproducing apparatus and an optical disk recording / reproducing method capable of recording and reproducing data at high density on an optical disk having such a configuration. .
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration example of an optical disc of the present invention.
FIG. 2 is a diagram illustrating a synchronization signal wobble on which a multiplexing mark is superimposed.
FIG. 3 is a diagram showing another configuration example of the optical disc of the present invention.
FIG. 4 is a block diagram illustrating a configuration example of an optical disk master manufacturing apparatus according to the present invention.
FIG. 5 is a diagram showing a configuration example of an optical disk recording / reproducing apparatus of the present invention.
FIG. 6 is a diagram illustrating recording of an address by wobbling.
FIG. 7 is an enlarged view of a main part for conceptually explaining a disk form.
FIG. 8 is a diagram showing a relationship between address data, a synchronous wobble reproduction waveform, and a multiplex mark reproduction waveform.
FIG. 9 is an embodiment of a circuit configuration for generating a multiplex mark signal and a synchronous wobble signal.
FIG. 10 is a diagram showing another configuration example of a reproduction signal processing system of the optical disc recording / reproduction device of the present invention.
[Explanation of symbols]
1 optical disc 4 multiplex mark 5 synchronization signal wobble (wobble)
20a Optical head (recording / reproducing means)
20c Multiplexed mark detection circuit (multiplexed mark detection means)
20d synchronization signal detection circuit (wobble detection means)
20e Bi-phase demodulation circuit 20f Address reading circuit m-1, m, m + 1 tracks

Claims (4)

An optical disc in which tracks for recording and reproducing data are formed by wobble displacement at a constant frequency in a direction between guide grooves ,
The said guide groove, the wobble displacement position synchronized position, multiplexing marks at a frequency higher than the frequency, and corresponding to one address information for one wobble period of the wobble is, the width of the guide groove optical disc but which is characterized in that it is formed synchronously displaced to be constant, on both side walls of the guide groove. An optical disc in which tracks for recording and reproducing data are formed by wobble displacement at a constant frequency in a direction between guide grooves,
The said guide groove, at a position that is synchronized with the wobble displacement position, multiplexing marks at a frequency higher than the frequency, and corresponding to one address information for one wobble period of the wobble is, both sides of the guide groove The width of the guide groove corresponding to the side wall position where the multiplex mark is formed is displaced on one of the side walls of the wall, and the width of the guide groove corresponding to the side wall position where the multiplex mark is not formed is An optical disc having a width at least as large as the width of the groove . An optical disc recording / reproducing apparatus for recording / reproducing data on / from an optical disc according to claim 1 or 2,
Recording / reproducing means for recording / reproducing data on / from the optical disc;
Multiplex mark detection means for detecting the multiplex mark from the reproduction output of the recording / reproduction means,
Wobble detecting means for detecting the wobble from the reproduction output;
An optical disc recording / reproducing apparatus comprising: an address information reading unit that reads the address information using the synchronization signal detected from the detected multiplex mark and the wobble . An optical disk recording / reproducing method for recording / reproducing data on / from an optical disk according to claim 1 or 2,
Detecting the multiplexed mark and the wobble from a reproduction output obtained by reproducing the optical disc,
An optical disk recording / reproducing method, wherein the address information is read using the synchronization signal detected from the detected multiplex mark and the wobble .

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