JP2003317257A - Optical disk drive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk drive by which a precise LPP signal free from noise components can be detected without receiving influence of RF components by a recorded disk, influence of a recording pulse in recording, and influence from the change of the reflectance of an information recording surface. <P>SOLUTION: When extracting the LPP signal of the recorded disk, a sub- beam LPP signal is extracted from a sub-beam detection signal obtained by a sub-beam following a land part where LPP is formed on an optical disk 1, and a phase difference between a main beam and the sub-beam caused by positional deviation on the information recording surface is corrected with respect to the sub-beam LPP signal to extract the LPP signal. In extracting the LPP signal during a recording operation, gain switching corresponding to the amplitude of a recording pulse is performed and thereafter the phase difference is corrected for extracting the LPP signal. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

The present invention relates to a recording medium D
The present invention relates to an optical disk device that records and reproduces information on an optical disk such as a VD-R / RW.

[0002]

2. Description of the Related Art In recent years, a writable and rewritable optical disc such as a DVD-R / RW, which has been widely used as a recording medium for large-capacity information,
A conventional optical disk device for recording and reproducing information will be described below with reference to FIGS. 9 and 10.

FIG. 9 is a block diagram showing a schematic structure of a conventional optical disk device, and FIG. 10 shows a structure of an information recording surface of an optical disk conventionally used in an optical disk device and a light spot irradiated on the information recording surface. It is a schematic diagram showing arrangement.

The optical disc 1 has concentric or spiral information recording tracks, and as shown in FIG.
The information recording tracks are formed by wobbling grooves, and land prepits (LPP: Land P) are formed at lands between the information recording tracks at intervals according to a predetermined law.
re Pit) is formed.

This LPP is an address pit and is used to obtain address information of an unrecorded disc and an address at the time of additional recording, and when an information is recorded on the optical disc in an optical disc device, it is detected as an LPP signal from the optical disc. is doing.

On the other hand, the laser output from the laser oscillation means 3 such as a laser diode is split into a main beam and a sub beam by the laser spectroscopic means 4, and based on the main beam and the sub beam, a light spot forming means 5 respectively. As shown in FIG. 10, a main beam spot that follows a track formed on the optical disc 1 and two sub-beam spots that are displaced by about ½ track from the main beam spot in the disc inner and outer peripheral directions are provided. It is formed.

The main beam spot and the sub beam spot are applied to the information recording surface of the rotating optical disc 1 by the rotation driving means 2. The reflected light from the main beam spot and the sub beam spot is detected by the light spot detection means 6.

Here, the light spot detecting means 6 is a main beam detecting means 7 for detecting the reflected light of the main beam spot, an inner peripheral side sub beam detecting means 8 and an outer peripheral side sub beam detecting means for detecting the reflected light of the sub beam spot. 9 and 9. Further, the detection signal from the light spot detection means 6 includes an RF signal due to a difference in the amount of light reflected from the information recording surface, a focus error signal, a tracking error signal, a wobble signal due to a wobbling groove, the above LPP signal and the like. .

The servo signal generation means 10 generates a tracking error signal and a focus error signal based on the detection signal from the light spot detection means 6. The servo means 11 generates a focus actuator control signal that is controlled so that the light spot from the light spot forming means 5 follows the information recording surface of the optical disc 1 based on the focus error signal, and also based on the tracking error signal. To
A tracking actuator control signal is generated so that the light spot from the light spot forming means 5 is controlled to follow the track on the information recording surface. The drive unit 12 controls the light spot forming unit 5 by the focus actuator control signal and the tracking actuator control signal.

FIG. 9 shows the conventional LPP signal detecting means.
And it demonstrates using FIG. FIG. 11 is a waveform diagram showing the operation of the conventional optical disk device. The signal detected by the main beam detecting means 7 is input to the push-pull signal generating means 30 to generate a main beam push-pull signal (r) which is a difference signal of the signals divided into two in the horizontal direction with respect to the information recording track. . The main beam push-pull signal (r) includes an LPP component, a wobble component, and an RF component in the case of a recorded disc.

The LPP component maximum value detecting means 25 detects the LPP component maximum value contained in the main beam push-pull signal (r). Further, the wobble signal detecting means 26 detects the wobble component from the main beam push-pull signal (r) including the LPP component, the wobble component and the RF component to obtain the wobble signal (s).

The wobble signal maximum value detecting means 27 detects the maximum value of the wobble signal (s) to obtain the maximum wobble signal value. In the LPP slice level determining means 28, from the LPP component maximum value and the wobble signal maximum value,
Determine the LPP slice level.

Therefore, in the comparator 29, the LP
The main beam push-pull signal (r) is binarized according to the P slice level to obtain the LPP signal (t).

[0014]

However, in the conventional optical disk device as described above, since the LPP slice level is determined by the maximum value of the LPP component and the maximum value of the wobble signal, the LPP signal from the recorded medium, If an attempt is made to extract the LPP signal during recording, the main beam push-pull signal is added to the RF by the recording mark.
Components, recording pulse components, and variations in the reflected light gain due to changes in the reflectance of the information recording surface are included, and these noise components affect the LPP slice level
There is a problem that it may be erroneously detected as a P signal.

The present invention solves the above-mentioned conventional problems and is not affected by the influence of the RF component due to the recorded disc, the influence of the recording pulse at the time of recording, or the influence of the change in the reflectance of the information recording surface. In addition, there is provided an optical disk device capable of detecting an accurate LPP signal having no noise component.

[0016]

In order to solve the above-mentioned problems, the optical disk device of the present invention has pits at predetermined intervals between tracks which are concentric or spiral on the information recording surface and which are formed by wobbling grooves. A rotation driving unit that rotationally drives an optical disc on which is formed, a laser oscillating unit that outputs a laser, a main beam that follows the track based on the laser, and a direction perpendicular to the track from the main beam. Light spot forming means for forming at least one or more sub-beams shifted to, and optically converging those beams to form light spots corresponding to the main beam and the sub-beams on the information recording surface; Main beam detecting means for detecting a light spot of the main beam reflected from a recording surface; At least one or more sub-beam detection means for detecting the light spot of the sub-beam reflected from the information recording surface, servo signal generation means for generating a servo signal from the detection signals of the main beam detection means and the sub-beam detection means, The optical spot is provided by the driving means, the servo means generating a control signal for controlling the driving of the light spot forming means from the servo signal, and the driving means driving the light spot forming means by the control signal. An optical disk device for generating a land pre-pit (LPP) signal corresponding to a pit between the tracks in order to obtain information of a target address when information is recorded / reproduced on / from the optical disk while driving the forming means. , The sub-beam detection signal detected by the sub-beam detection means The sub-beam LPP signal detecting means for detecting the sub-beams LPP signal for obtaining said LPP signal from provided, said sub-beams LPP
The LPP signal is generated based on the signal.

As described above, when the LPP signal of the recorded disc is extracted, the sub-beam LPP signal is extracted from the sub-beam detection signal obtained from the sub-beam that follows the land portion of the optical disc where the LPP is formed. When the LPP signal is extracted and the LPP signal during recording is extracted by correcting the phase difference caused by the displacement of the main beam and the sub beam on the information recording surface with respect to the sub beam LPP signal,
The LPP signal can be extracted by correcting the phase difference after switching the gain according to the amplitude of the recording pulse.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION In the optical disk device according to claim 1 of the present invention, pits are formed at predetermined intervals between tracks which are concentric or spiral and are formed by wobbling grooves on an information recording surface. The optical disc is rotated in a direction perpendicular to the track based on the laser, a rotary drive unit for rotationally driving, a laser oscillating unit for outputting a laser, a laser, and a main beam that follows the track. Light spot forming means for generating at least one or more sub-beams, optically converging those beams, and forming a light spot corresponding to the main beam and the sub-beams on the information recording surface, and reflecting from the information recording surface Main beam detecting means for detecting the light spot of the main beam thus generated, and reflection from the information recording surface At least one or more sub beam detecting means for detecting a light spot of the sub beam, a servo signal generating means for generating a servo signal from detection signals of the main beam detecting means and the sub beam detecting means, and the servo signal from the servo signal. The optical spot forming means is provided with a servo means for generating a control signal for driving and controlling the light spot forming means, and a driving means for driving the light spot forming means by the control signal. However, in the case of recording / reproducing information on / from the optical disc, the sub-beam detection is performed in the optical disc device for generating the land pre-pit (LPP) signal corresponding to the pit between the tracks in order to obtain the information of the target address. From the sub-beam detection signal detected by the means. The sub-beam LPP signal detecting means for detecting the sub-beams LPP signal for obtaining provided, on the basis of the sub-beam LPP signal, and configured to generate the LPP signal.

According to this structure, when the LPP is extracted from the recorded disc or the LPP is being recorded,
A sub-beam LPP signal that is not affected by recording marks or recording pulses is extracted, and the LPP signal is extracted based on this sub-beam LPP signal.

An optical disk device according to a second aspect is the optical disk device according to the first aspect, further comprising push-pull signal generation means for generating a push-pull signal from the main beam detection signal detected by the main beam detection means. , A main beam LPP signal detecting means for detecting a main beam LPP signal from the push-pull signal, and the main beam LPP for the sub-beam LPP signal.
By correcting the LPP phase difference generated between the signal and the LP,
A phase difference correction means for generating a P signal is provided.

According to this structure, when the sub-beam is arranged in the tangential direction with respect to the track of the optical disk with respect to the main beam, the sub-beam LPP signal which is not affected by the recording mark, recording pulse, etc. , LPP signal is extracted by performing phase correction so that there is no phase difference from the main beam LPP signal.

An optical disk device according to a third aspect of the present invention is the optical disk device according to the first or second aspect, wherein the sub-beam detection signal detected by the sub-beam detection means is in accordance with the recording power during information recording. On the other hand, the gain switching means for switching the gain and supplying it to the sub-beam LPP signal detecting means is provided.

According to this structure, when the LPP is extracted at the time of recording, the recording power is changed during recording, the recording mark is being recorded on the information recording surface, and the reflection of the information recording surface occurs when the recording mark is generated. A sub-beam LPP signal that is not affected by a change in the rate is extracted, and an LPP signal is extracted based on this sub-beam LPP signal.

In the optical disk device according to a fourth aspect of the present invention, an optical disk in which pits are formed at predetermined intervals between tracks formed concentrically or spirally on the information recording surface and formed by wobbling grooves is rotated. Drive means, laser oscillation means for outputting a laser, a main beam that follows the track based on the laser, and at least one or more sub-beams that are shifted from the main beam in a direction perpendicular to the track. Light spot forming means for generating and optically converging those beams to form a light spot corresponding to the main beam and the sub-beam, and the light of the main beam reflected from the information recording surface. Main beam detecting means for detecting a spot, and the sub beam reflected from the information recording surface. At least one sub-beam detecting means for detecting a light spot of a beam, a servo signal generating means for generating a servo signal from detection signals of the main beam detecting means and the sub-beam detecting means, and forming the light spot from the servo signal. Servo means for generating a control signal for driving and controlling the means, and driving means for driving the light spot forming means according to the control signal, while driving the light spot forming means by the driving means, A sub-beam detection signal detected by the sub-beam detection means in an optical disk device that generates an LPP signal corresponding to the pits between the tracks in order to obtain information of the target address when recording / reproducing information on / from the optical disk. From the sub-beam LPP signal to obtain the LPP signal from Sub-beam LPP signal detecting means for outputting, push-pull signal generating means for generating a push-pull signal from the main beam detection signal detected by the main beam detecting means, and main beam for detecting a main beam LPP signal from the push-pull signal LPP signal detecting means and the sub-beam LPP
LPP phase difference detection means for detecting an LPP phase difference between the signal and the main beam LPP signal,
The wobble cycle is provided from the servo signal generated by the servo signal generating means, and a wobble cycle LPP phase difference correlation means that correlates the wobble cycle and the LPP phase difference is provided. Based on the correlation by the LPP phase difference correlation means, the sub-beam LPP signal is phase-corrected based on the wobble period so that there is no phase difference from the main beam LPP signal, and an LPP signal is generated. .

According to this structure, when the sub-beam is displaced from the main beam in the tangential direction with respect to the track of the optical disc, the wobble period LPP phase difference correlating means determines the recording mark based on the wobble period. The LPP signal is extracted by performing phase correction on the sub-beam LPP signal that is not affected by the recording pulse or the like so as to eliminate the phase difference from the main beam LPP signal.

According to a fifth aspect of the present invention, there is provided an optical disc device including the wobble period LPP phase difference correlation means according to the fourth aspect.
Correlation is performed using the period ratio for the LPP phase difference based on the wobble period.

According to this structure, even if the rotation speed of the optical disk changes, the sub-beam LPP signal which is not affected by the recording mark or the recording pulse by the correction value obtained from the period ratio to the LPP phase difference based on the wobble period. On the other hand, the LPP signal is extracted by performing the phase correction so as to eliminate the phase difference from the main beam LPP signal.

According to a sixth aspect of the present invention, there is provided an optical disc device in which the wobble period LPP phase difference correlating means according to the fourth or fifth aspect is a correlation equation (correction value = wobble period after change × LPP phase difference ÷ wobble period). ) Is used to correlate the wobble period and the LPP phase difference.

According to this structure, even when the rotation speed of the optical disk changes, the recording mark, the recording pulse, etc. can be obtained by the correction value obtained from the correlation formula (correction value = wobble cycle after change × LPP phase difference / wobble cycle). To the main beam LPP signal that is not affected by
Phase correction is performed so that there is no phase difference with the signal, and the LPP signal is extracted.

An optical disc device according to a seventh aspect is the optical disc device according to the fourth aspect, the fifth aspect, or the sixth aspect, wherein the sub-beam detecting means detects the optical power according to the recording power during information recording. A gain switching means for switching the gain for the sub-beam detection signal and supplying the gain to the sub-beam LPP signal detection means is provided.

According to this structure, when the LPP is extracted at the time of recording, a change in recording power during recording, a recording mark during recording on the information recording surface, or a reflection of the information recording surface that occurs when the recording mark is generated. A sub-beam LPP signal that is not affected by a change in the rate is extracted, and an LPP signal is extracted based on this sub-beam LPP signal.

An optical disk device according to a eighth aspect of the present invention is an optical disk device for rotating an optical disk having pits formed at predetermined intervals between tracks formed concentrically or spirally on an information recording surface and formed by wobbling grooves. Drive means, laser oscillation means for outputting a laser, a main beam that follows the track based on the laser, and at least one or more sub-beams that are shifted from the main beam in a direction perpendicular to the track. Light spot forming means for generating and optically converging those beams to form a light spot corresponding to the main beam and the sub-beam, and the light of the main beam reflected from the information recording surface. Main beam detecting means for detecting a spot, and the sub beam reflected from the information recording surface. At least one sub-beam detecting means for detecting a light spot of a beam, a servo signal generating means for generating a servo signal from detection signals of the main beam detecting means and the sub-beam detecting means, and forming the light spot from the servo signal. Servo means for generating a control signal for driving and controlling the means, and driving means for driving the light spot forming means according to the control signal, while driving the light spot forming means by the driving means, A sub-beam detection signal detected by the sub-beam detection means in an optical disk device that generates an LPP signal corresponding to the pits between the tracks in order to obtain information of the target address when recording / reproducing information on / from the optical disk. From the sub-beam LPP signal to obtain the LPP signal from Sub-beam LPP signal detecting means for outputting, push-pull signal generating means for generating a push-pull signal from the main beam detection signal detected by the main beam detecting means, and main beam for detecting a main beam LPP signal from the push-pull signal LPP signal detecting means and the sub-beam LPP
LPP phase difference detection means for detecting an LPP phase difference between the signal and the main beam LPP signal,
L for detecting an LPP cycle based on the sub-beam LPP signal detected by the sub-beam LPP signal detecting means
PP cycle detection means and LPP cycle LPP phase difference correlation means for correlating the LPP cycle and the LPP phase difference are provided, and based on the correlation by the LPP cycle LPP phase difference correlation means, based on the LPP cycle. , The sub-beam LP
The P signal is phase-corrected so that there is no phase difference from the main beam LPP signal, and the LPP signal is generated.

According to this structure, when the sub-beam is displaced from the main beam in the tangential direction with respect to the track of the optical disk, the LPP period L
The sub-beam LP that is not affected by recording marks or recording pulses based on the LPP cycle by the PP phase difference correlation means.
The P signal is phase-corrected so that there is no phase difference from the main beam LPP signal, and the LPP signal is extracted.

According to a ninth aspect of the present invention, there is provided an optical disk device, wherein the LPP period LPP phase difference correlation means according to the eighth aspect is L
The correlation is configured by using the period ratio for the LPP phase difference based on the PP period.

According to this structure, even if the rotation speed of the optical disk changes, the sub-beam LPP signal which is not affected by the recording mark or the recording pulse by the correction value obtained from the period ratio to the LPP phase difference based on the LPP period. On the other hand, the LPP signal is extracted by performing the phase correction so as to eliminate the phase difference from the main beam LPP signal.

According to a tenth aspect of the present invention, there is provided an optical disc device according to the eighth or ninth aspect, wherein the LPP period LPP phase difference correlating means has a correlation equation (correction value = changed LPP period ××
LPP phase difference / LPP cycle) is used to establish a correlation between the LPP cycle and the LPP phase difference.

According to this structure, even if the rotation speed of the optical disk changes, the correlation equation (correction value = LPP after change)
The sub-beam LPP signal that is not affected by recording marks or recording pulses is phase-corrected so that there is no phase difference from the main beam LPP signal by the correction value obtained from (cycle × LPP phase difference / LPP cycle). Extract the LPP signal.

The optical disk device described in claim 11 is the optical disk device according to claim 8 or claim 9 or claim 10 and is detected by the sub-beam detection means in accordance with the recording power during information recording. The gain is switched for the sub-beam detection signal, and the sub-beam LP
A configuration is provided in which a gain switching unit that supplies the P signal detection unit is provided.

According to this structure, when the LPP is extracted at the time of recording, the recording power is changed during recording, the recording mark is being recorded on the information recording surface, and the reflection of the information recording surface occurs when the recording mark is generated. A sub-beam LPP signal that is not affected by a change in the rate is extracted, and an LPP signal is extracted based on this sub-beam LPP signal.

According to a twelfth aspect of the present invention, in the optical disc apparatus, the optical disc having concentric circles or spirals on the information recording surface and having pits formed at predetermined intervals between the tracks formed by the wobbling groove is rotated and driven. Drive means, laser oscillation means for outputting a laser, a main beam that follows the track based on the laser, and at least one or more sub-beams that are shifted from the main beam in a direction perpendicular to the track. Light spot forming means for generating and optically converging those beams to form a light spot corresponding to the main beam and the sub-beam, and the light of the main beam reflected from the information recording surface. Main beam detecting means for detecting a spot and the sub beam reflected from the information recording surface. At least one sub-beam detecting means for detecting a light spot of a beam, a servo signal generating means for generating a servo signal from detection signals of the main beam detecting means and the sub-beam detecting means, and the light spot from the servo signal. Servo means for generating a control signal for driving and controlling the forming means, and drive means for driving the light spot forming means by the control signal, while driving the light spot forming means by the drive means, When information is recorded / reproduced on / from the optical disc, in order to obtain information on the target address,
In an optical disc device for generating an LPP signal corresponding to a pit between tracks, a sub-beam LPP signal detecting means for detecting a sub-beam LPP signal for obtaining the LPP signal from the sub-beam detecting signal detected by the sub-beam detecting means, Push-pull signal generation means for generating a push-pull signal from the main beam detection signal detected by the main beam detection means, main beam LPP signal detection means for detecting a main beam LPP signal from the push-pull signal, and the sub-beam LP.
An LPP phase difference detecting unit that detects an LPP phase difference generated between the P signal and the main beam LPP signal, and a sub beam that acquires address information of the sub beam LPP signal detected by the sub beam LPP signal detecting unit. LPP address acquisition means, address increase rate calculation means for calculating an increase rate of the sub-beam LPP address information within a predetermined time to obtain an address increase rate, and an address for correlating the address increase rate with the LPP phase difference. An increase rate LPP phase difference correlation means is provided, and a phase difference between the main beam LPP signal and the sub-beam LPP signal is generated based on the address increase rate based on the correlation by the address increase rate LPP phase difference correlation means. The phase is corrected so that the LPP signal disappears, and the LPP signal is generated.

According to this structure, when the sub-beams are displaced from the main beam in the tangential direction with respect to the track of the optical disk, the sub-beam LPP signals are obtained by the address increase rate LPP phase difference correlation means. Based on the address increase rate, the sub-beam LPP signal that is not affected by recording marks or recording pulses is phase-corrected so as to have no phase difference from the main beam LPP signal, and the LPP signal is extracted.

According to a thirteenth aspect of the present invention, there is provided an optical disk device according to the twelfth aspect, wherein the address increase rate LPP phase difference correlation means determines the ratio of the LPP phase difference to the period based on the address increase rate obtained from the sub-beam LPP signal. It is configured to use the correlation.

According to this structure, even when the rotation speed of the optical disk changes, the recording mark or the recording pulse is corrected by the correction value obtained from the ratio of the LPP phase difference to the period based on the address increase rate obtained from the sub-beam LPP signal. The sub-beam LPP signal that is not affected by the above is subjected to phase correction so that there is no phase difference from the main beam LPP signal, and the LPP signal is extracted.

According to a fourteenth aspect of the present invention, there is provided the optical disc device according to the twelfth or thirteenth aspect, wherein the address increase rate L
The PP phase difference correlation means is configured to take a correlation between the address increase rate and the LPP phase difference by using a correlation equation (correction value = address change rate after change × LPP phase difference ÷ address increase rate).

According to this structure, even when the rotation speed of the optical disk changes, the recording mark and the recording are recorded by the correction value obtained from the correlation equation (correction value = address increase rate after change × LPP phase difference / address increase rate). For the sub-beam LPP signal that is not affected by pulses, etc., the main beam L
Phase correction to eliminate the phase difference from the PP signal
Extract the P signal.

An optical disc device according to a fifteenth aspect is the optical disc device according to the twelfth aspect, the thirteenth aspect, or the fifteenth aspect, wherein the sub-beam detecting means detects the optical power according to a recording power during information recording. A gain switching means for switching the gain for the sub-beam detection signal and supplying the gain to the sub-beam LPP signal detection means is provided.

According to this structure, when the LPP is extracted at the time of recording, the recording power is changed during recording, the recording mark is being recorded on the information recording surface, and the reflection of the information recording surface occurs when the recording mark is generated. A sub-beam LPP signal that is not affected by a change in the rate is extracted, and an LPP signal is extracted based on this sub-beam LPP signal.

An optical disk device showing an embodiment of the present invention will be specifically described below with reference to the drawings. (Embodiment 1) An optical disk device according to Embodiment 1 of the present invention will be described.

FIG. 1 is a block diagram showing a schematic configuration of the optical disc device of the first embodiment, and FIG. 2 is a waveform diagram showing an operation in the optical disc device of the first embodiment.
As shown in FIG. 1, this optical disk device includes an optical disk 1, a rotation driving means 2, a laser oscillation means 3, a laser spectroscopic means 4, a light spot forming means 5, a light spot detecting means 6, and a main beam. Detecting means 7, inner peripheral side sub-beam detecting means 8, outer peripheral side sub-beam detecting means 9, servo signal generating means 10, servo means 11, driving means 12, gain switching means 13, sub-beam LPP.
It is composed of a signal detecting means 14 and a phase difference correcting means 15.

As shown in FIG. 10, the optical disc 1 has information recording tracks which are concentric or spiral and which are formed by wobbling grooves on the information recording surface, and between the information recording tracks on the information recording surface. Pits (LPP) are formed in the land portion at predetermined intervals.

The laser beam emitted from the laser oscillating means 3 is shifted by the laser beam splitting means 4 to the main beam following the track and to the inner and outer circumference sides from the main beam by about ½ track pitch with respect to the track. It is split into an inner peripheral side sub-beam and an outer peripheral side sub-beam. The light spot forming means 5 forms a main beam, an inner peripheral side sub-beam, and an outer peripheral side sub-beam in the form of light spots, respectively, and irradiates the information recording surface of the rotating optical disc 1 with the rotation driving means 2.

The reflected light of the light spot is detected by the light spot detecting means 6. Here, the reflected light of the main beam is detected by the main beam detecting means 7, and the reflected light of the inner peripheral side sub-beam and the outer peripheral side sub-beam are detected by the inner peripheral side sub-beam detecting means 8 and the outer peripheral side sub-beam detecting means 9, respectively. .

The signal detected by the light spot detecting means 6 is input to the servo signal generating means 10. The detection signal from the light spot detection means 6 includes a reproduction signal due to the difference in the amount of light reflected from the information recording surface, a focus error signal, a tracking error signal, a wobble signal, an LPP signal and the like.

The servo signal generation means 10 generates a tracking error signal and a focus error signal based on the detection signal from the light spot detection means 6, and the servo means 1
Supply to 1. The servo means 11 generates a focus actuator control signal that is controlled so that the main light spot follows the information recording surface of the optical disc 1 from the focus error signal, and the main light spot indicates that the main light spot is from the tracking error signal. Tracking actuator control signals that are controlled so as to follow the track are generated, and the driving unit 12 drives and moves the light spot forming unit 5 using these control signals.

Next, the extraction of the LPP signal will be described. The detection signal of the outer peripheral side sub-beam detection means 9 is input to the gain switching means 13, and, for example, in the case of recording,
The gain is switched according to the intensity (amplitude) of the recording pulse and is input to the sub-beam LPP signal detecting means 14. Here, the LPP address information of the track followed by the main beam spot is formed in the land portion on the outer peripheral side of the track. The sub-beam LPP signal detecting means 14 is configured by the same technique as the conventional LPP signal detecting means, for example.

The sub-beam LPP signal (b) is obtained by slicing the sub-beam detection signal (a) detected by the outer peripheral side sub-beam detection means 9 at the LPP slice level. Here, since the sub-beam detection signal (a) detected by the outer peripheral side sub-beam detection unit 9 is not originally affected by the recording mark, the LPP component can be stably sliced.

Since the main beam and the outer sub-beam are displaced from each other in the tangential direction with respect to the track of the optical disc 1, the sub-beam LPP signal (b) is the main beam LPP detected from the main beam.
It has a phase shift with respect to the signal. In order to correct this phase shift, the phase difference correction means 15 performs phase difference correction on the outer peripheral side sub-beam LPP signal so as to be in phase with the main beam LPP signal detected from the main beam, and then the phase correction LPP signal. (C) is obtained.

As described above, the LPP of the recorded disc
In extraction of LPP and extraction of LPP during recording, it is possible to obtain a sub-beam LPP signal that is not affected by recording marks, recording pulses, and the like, and by further correcting the phase difference,
An accurate LPP signal can be obtained. (Second Embodiment) An optical disk device according to a second embodiment of the present invention will be described.

FIG. 3 is a block diagram showing a schematic configuration of the optical disk device of the second embodiment, and FIG. 4 is a waveform diagram showing the operation of the optical disk device of the second embodiment.
As shown in FIG. 3, this optical disk device includes an optical disk 1, a rotation driving means 2, a laser oscillating means 3, a laser spectroscopic means 4, a light spot forming means 5, a light spot detecting means 6, and a main beam. Detecting means 7, inner peripheral side sub-beam detecting means 8, outer peripheral side sub-beam detecting means 9, servo signal generating means 10, servo means 11, driving means 12, gain switching means 13, sub-beam LPP.
Signal detection means 14 and push-pull signal generation means 30
The main beam LPP signal detecting means 16, the LPP phase difference detecting means 17, the wobble cycle detecting means 18, the wobble cycle LPP phase difference correlating means 19, and the phase difference correcting means 15.

As shown in FIG. 10, the optical disc 1 has information recording tracks which are concentric or spiral and are formed by wobbling grooves on the information recording surface, and the information recording surface has a space between the information recording tracks. Pits (LPP) are formed in the land portion at predetermined intervals.

The laser beam emitted from the laser oscillating means 3 is moved by the laser beam splitting means 4 to the main beam following the information recording track and to the inner and outer circumference sides by about ½ track pitch from the main beam to the track. The light is split into the shifted inner circumference side sub-beam and outer circumference side sub-beam. The light spot forming means 5 forms a light spot corresponding to each of the main beam, the inner peripheral side sub-beam and the outer peripheral side sub-beam, and irradiates the information recording surface of the rotating optical disc 1 by the rotation driving means 2. .

The reflected light of the light spot thus irradiated from the information recording surface is detected by the light spot detecting means 6. In this light spot detecting means 6, the reflected light of the main beam is detected by the main beam detecting means 7, and the reflected light of the inner peripheral side sub-beam and the outer peripheral side sub-beam are respectively the inner peripheral side sub-beam detecting means 8 and the outer peripheral side sub-beam detecting means. 9 is detected. The signal detected by the light spot detection means 6 is input to the servo signal generation means 10. Here, the detection signal from the light spot detection means 6 includes a reproduction signal due to a difference in the amount of light reflected from the information recording surface, a focus error signal, a tracking error signal, a wobble signal, an LPP signal and the like.

The servo signal generation means 10 generates a tracking error signal and a focus error signal based on the detection signal from the light spot detection means 6, and the servo means 1
Supply to 1. The servo means 11 generates a focus actuator control signal that is controlled so that the main light spot follows the information recording surface of the optical disc 1 from the focus error signal, and the main light spot indicates that the main light spot is from the tracking error signal. Tracking actuator control signals that are controlled so as to follow the track are generated, and the driving unit 12 drives and moves the light spot forming unit 5 using these control signals.

Next, the extraction of the LPP signal will be described. In order to correct the phase difference of the LPP signal, the wobble period (a) of the binarized wobble signal (h) and the LPP phase difference (a) between the main beam LPP signal (f) and the sub beam LPP signal (g) are previously set. Correlate with. Also,
At the stage of correlating the wobble period (a) and the LPP phase difference (a), the binarized wobble signal (h), the main beam LPP signal (f) and the sub beam LPP signal (g) in the unrecorded disc are used.

The procedure for correlating the wobble period (a) and the LPP phase difference (a) will be described below. The outer peripheral side sub-beam detection signal (e) detected by the outer peripheral side sub-beam detecting means 9 is input to the gain switching means 13,
For example, during recording, the gain is switched according to the intensity (amplitude) of the recording pulse, and the sub beam LPP
The sub-beam LPP signal (g) is generated by being input to the signal detection means 14 and sliced at the LPP slice level.

The signal detected by the main beam detecting means 7 is input to the push-pull signal generating means 30 to obtain the main beam push-pull signal (d). The main beam push-pull signal (d) is the main beam L
The main beam LPP signal (f) is generated by being input to the PP signal detection means 16 and sliced at the LPP slice level. Here, the sub-beam LPP signal (g) and the main beam LPP signal (f) are, for example, conventional LPs.
It is generated by the method described in P signal extraction method.

The main beam LPP signal (f) and the sub beam LPP signal (g) are input to the LPP phase difference detecting means 17, and the LPP phase difference which is the phase difference between the main beam LPP signal (f) and the sub beam LPP signal (g). (A) is detected. This LPP phase difference (a) is generated because the sub beam and the main beam are displaced from the track of the optical disc 1 in the tangential direction.

On the other hand, the binarized wobble signal (h) generated by the servo signal generation means 10 is input to the wobble cycle detection means 18 and the wobble cycle (a) is detected. The wobble period LPP phase difference correlation means 19
The correlation between the P phase difference (A) and the wobble period (A) is taken,
Store correlation information. Here, since both the LPP phase difference (A) and the wobble period (A) are units of time, the correlation information can be expressed as a ratio of time. That is, even when the wobble period (a) changes due to a change in the rotation speed of the optical disc 1 or the like, it is possible to obtain the corrected LPP phase difference for performing correction using the correlation expression shown in the expression (A), for example. .

Correction value = wobble period after change × LPP phase difference / wobble period (A) Since the above correlation information only needs to be stored once,
A system in which the correlation information is acquired only in the first adjustment step may be used. For the same reason, the main beam LP
The P signal detection means 16 and the LPP phase difference detection means 17 may be configured outside the optical disk device.

Next, the phase difference correcting means 15 corrects the phase of the sub-beam LPP signal (g) detected by the sub-beam LPP signal detecting means 14 by the corrected LPP phase difference correlated with the expression (A). Then, an LPP signal having the same phase as the main beam LPP signal (f) is obtained.

As described above, by extracting the sub-beam LPP signal (g), it is possible to extract the sub-beam LPP signal which is not affected by the recording mark or the recording pulse even when the disc is already recorded or during recording. Further, by performing the phase correction of the sub-beam LPP signal (g), an LPP signal equivalent to the main beam LPP signal (f) can be extracted even when the rotation speed of the optical disc 1 changes. (Third Embodiment) An optical disk device according to a third embodiment of the present invention will be described.

FIG. 5 is a block diagram showing a schematic configuration of the optical disc device of the third embodiment, and FIG. 6 is a waveform diagram showing the operation of the optical disc device of the third embodiment.
As shown in FIG. 5, this optical disk device includes an optical disk 1, a rotation driving means 2, a laser oscillation means 3, a laser spectroscopic means 4, a light spot forming means 5, a light spot detecting means 6, and a main beam. Detecting means 7, inner peripheral side sub-beam detecting means 8, outer peripheral side sub-beam detecting means 9, servo signal generating means 10, servo means 11, driving means 12, gain switching means 13, sub-beam LPP.
Signal detection means 14 and push-pull signal generation means 30
A main beam LPP signal detecting means 16, an LPP phase difference detecting means 17, an LPP cycle detecting means 20, and an LP.
P period LPP phase difference correlation means 21 and phase difference correction means 1
It is composed of 5 and 5.

As shown in FIG. 10, the optical disc 1 has information recording tracks which are concentric or spiral and formed by wobbling grooves on the information recording surface, and the information recording surface has a space between the information recording tracks. Pits (LPP) are formed in the land portion at predetermined intervals.

The laser beam emitted from the laser oscillating means 3 is moved by the laser spectroscopic means 4 to the main beam following the information recording track and to the inner and outer circumference sides from the main beam by a track pitch of about ½ of the track. The light is split into the shifted inner circumference side sub-beam and outer circumference side sub-beam. The light spot forming means 5 forms a light spot corresponding to each of the main beam, the inner peripheral side sub-beam and the outer peripheral side sub-beam, and irradiates the information recording surface of the rotating optical disc 1 by the rotation driving means 2. .

The reflected light of the light spot thus irradiated from the information recording surface is detected by the light spot detecting means 6. In this light spot detecting means 6, the reflected light of the main beam is detected by the main beam detecting means 7, and the reflected light of the inner peripheral side sub-beam and the outer peripheral side sub-beam are respectively the inner peripheral side sub-beam detecting means 8 and the outer peripheral side sub-beam detecting means. 9 is detected. The signal detected by the light spot detection means 6 is input to the servo signal generation means 10. Here, the detection signal from the light spot detection means 6 includes a reproduction signal due to a difference in the amount of light reflected from the information recording surface, a focus error signal, a tracking error signal, a wobble signal, an LPP signal and the like.

The servo signal generation means 10 generates a tracking error signal and a focus error signal based on the detection signal from the light spot detection means 6, and the servo means 1
Supply to 1. The servo means 11 generates a focus actuator control signal that is controlled so that the main light spot follows the information recording surface of the optical disc 1 from the focus error signal, and the main light spot indicates that the main light spot is from the tracking error signal. Tracking actuator control signals that are controlled so as to follow the track are generated, and the driving unit 12 drives and moves the light spot forming unit 5 using these control signals.

Next, the extraction of the LPP signal will be described. In order to correct the phase difference of the LPP signal, the LPP phase difference (c) is correlated with the LPP cycle (d) or (e) in advance. Also, the LPP phase difference (c) and L
At the stage of correlating the PP cycle (D) or (E),
Main beam LPP signal (k) on unrecorded disc
And the sub-beam LPP signal (l).

The procedure for obtaining the correlation between the LPP phase difference (c) and the LPP cycle (d) or (e) will be described below.
The outer peripheral side sub-beam detection signal (j) detected by the outer peripheral side sub-beam detecting means 9 is gain switching means 13
For example, during recording, the gain is switched according to the intensity (amplitude) of the recording pulse, is further input to the sub-beam LPP signal detecting means 14, and is sliced at the LPP slice level to obtain the sub-beam LPP signal (l ) Is generated.

The main beam detection signal detected by the main beam detection means 7 is input to the push-pull signal generation means 30 to obtain the main beam push-pull signal (i). Main beam push-pull signal (i)
Is input to the main beam LPP signal detection means 16,
Main beam L sliced at LPP slice level
The PP signal (k) is generated. Where sub beam LP
The P signal (l) and the main beam LPP signal (k) are
For example, it is generated by the method described in the conventional LPP signal extraction method.

The main beam LPP signal (k) and the sub beam LPP signal (l) are input to the LPP phase difference detecting means 17, and the LPP phase difference which is the phase difference between the main beam LPP signal (k) and the sub beam LPP signal (l). (C) is detected. This LPP phase difference (c) is generated because the sub beam and the main beam are displaced in the tangential direction with respect to the track of the optical disc 1.

On the other hand, the LPP signal (m) is composed of a predetermined signal pattern, and the LPP cycle (D) or (E) is detected from the sub-beam LPP signal detected by the sub-beam LPP signal detecting means 14. It is detected by the means 20. In the LPP cycle LPP phase difference correlation means 21, the LPP phase difference (c) and the LPP cycle (d)
Alternatively, it correlates with (e) and stores the correlation information.
Here, since the LPP phase difference (c) and the LPP cycle (d) or (e) are both units of time, the correlation information can be expressed as a time ratio, for example. That is,
Even if the LPP cycle (d) or (e) changes due to a change in the rotation speed of the optical disc 1 or the like, a correction LP for performing correction using, for example, the correlation expression shown in the expression (B)
The P phase difference can be obtained.

Correction value = LPP cycle after change × LPP phase difference / LPP cycle (B) Since the above correlation information only needs to be stored once,
A system in which the correlation information is acquired only in the first adjustment step may be used. For the same reason, the main beam LP
The P signal detection means 16 and the LPP phase difference detection means 17 may be configured outside the optical disk device.

Next, the phase difference correcting means 15 corrects the phase of the sub-beam LPP signal (l) detected by the sub-beam LPP signal detecting means 14 by the corrected LPP phase difference correlated with the equation (B). Then, an LPP signal having the same phase as the main beam LPP signal (k) is obtained.

As described above, by extracting the sub-beam LPP signal (l), it is possible to extract the sub-beam LPP signal which is not affected by the recording mark or the recording pulse even when the disc is already recorded or during recording. Further, by performing the phase correction of the sub-beam LPP signal (l), the LPP signal equivalent to the main beam LPP signal (k) can be extracted even when the rotation speed of the optical disc 1 changes. (Embodiment 4) An optical disk device according to Embodiment 4 of the present invention will be described.

FIG. 7 is a block diagram showing a schematic structure of the optical disk device of the fourth embodiment, and FIG. 8 is a waveform diagram showing the operation of the optical disk device of the fourth embodiment.
As shown in FIG. 7, this optical disk device includes an optical disk 1, a rotation driving means 2, a laser oscillating means 3, a laser spectroscopic means 4, a light spot forming means 5, a light spot detecting means 6, and a main beam. Detecting means 7, inner peripheral side sub-beam detecting means 8, outer peripheral side sub-beam detecting means 9, servo signal generating means 10, servo means 11, driving means 12, gain switching means 13, sub-beam LPP.
Signal detection means 14 and push-pull signal generation means 30
, Main beam LPP signal detection means 16, LPP phase difference detection means 17, sub-beam LPP address acquisition means 22, address increase rate calculation means 23, address increase rate LPP phase difference correlation means 24, and phase difference correction means. 15
It consists of and.

As shown in FIG. 10, the optical disc 1 has information recording tracks which are concentric or spiral and which are formed by wobbling grooves on the information recording surface, and between the information recording tracks on the information recording surface. Pits (LPP) are formed in the land portion at predetermined intervals.

The laser beam emitted from the laser oscillating means 3 is moved by the laser beam splitting means 4 to the main beam following the information recording track and to the inner and outer peripheral sides of the main beam by a track pitch of about ½ of the track. The light is split into the shifted inner circumference side sub-beam and outer circumference side sub-beam. The light spot forming means 5 forms a light spot corresponding to each of the main beam, the inner peripheral side sub-beam and the outer peripheral side sub-beam, and irradiates the information recording surface of the rotating optical disc 1 by the rotation driving means 2. .

The reflected light of the light spot thus irradiated from the information recording surface is detected by the light spot detecting means 6. In this light spot detecting means 6, the reflected light of the main beam is detected by the main beam detecting means 7, and the reflected light of the inner peripheral side sub-beam and the outer peripheral side sub-beam are respectively the inner peripheral side sub-beam detecting means 8 and the outer peripheral side sub-beam detecting means. 9 is detected. The signal detected by the light spot detection means 6 is input to the servo signal generation means 10. Here, the detection signal from the light spot detection means 6 includes a reproduction signal due to a difference in the amount of light reflected from the information recording surface, a focus error signal, a tracking error signal, a wobble signal, an LPP signal and the like.

The servo signal generation means 10 generates a tracking error signal and a focus error signal based on the detection signal from the light spot detection means 6, and the servo means 1
Supply to 1. The servo means 11 generates a focus actuator control signal that is controlled so that the main light spot follows the information recording surface of the optical disc 1 from the focus error signal, and the main light spot indicates that the main light spot is from the tracking error signal. Tracking actuator control signals that are controlled so as to follow the track are generated, and the driving unit 12 drives and moves the light spot forming unit 5 using these control signals.

Next, the extraction of the LPP signal will be described. In order to correct the phase difference of the LPP signal, the address increase rate and the LPP phase difference (f) are correlated in advance. At the stage of correlating the address increase rate and the LPP phase difference (f), the main beam LPP signal (p) and the sub beam LPP signal (q) in the unrecorded disc are used.

The procedure for obtaining the correlation between the address increase rate and the LPP phase difference (f) will be described below. The outer peripheral side sub-beam detection signal (o) detected by the outer peripheral side sub-beam detecting means 9 is input to the gain switching means 13, and the gain is switched according to the intensity (amplitude) of the recording pulse, for example, during recording. Further, it is inputted to the sub-beam LPP signal detecting means 14 and sliced at the LPP slice level to generate the sub-beam LPP signal (q).

The main beam detection signal detected by the main beam detection means 7 is input to the push-pull signal generation means 30 to obtain the main beam push-pull signal (n). Main beam push-pull signal (n)
Is input to the main beam LPP signal detection means 16,
Main beam L sliced at LPP slice level
The PP signal (p) is generated. Where sub beam LP
The P signal (q) and the main beam LPP signal (p) are
For example, it is generated by the method described in the conventional LPP signal extraction method.

The main beam LPP signal (p) and the sub beam LPP signal (q) are input to the LPP phase difference detecting means 17, and the LPP phase difference which is the phase difference between the main beam LPP signal (p) and the sub beam LPP signal (q). Detect (f). This LPP phase difference (f) occurs because the sub-beam and the main beam are displaced from each other on the track of the optical disc 1 in the tangential direction.

On the other hand, the sub-beam LPP signal detecting means 14
The sub-beam LPP signal detected by is input to the sub-beam LPP address acquisition means 22,
Address information of the sub-beam LPP is obtained based on the PP signal. Based on the address information of the sub-beam LPP, the address increase rate calculation means 23 calculates the address increase rate of the sub-beam LPP signal within a predetermined period and outputs this as the address increase rate.

Address increase rate LPP phase difference correlation means 24
Then, the address increase rate is correlated with the LPP phase difference (f), and the correlation information is stored. For example, even if the address increase rate changes due to a change in the rotation speed of the optical disc 1 or the like, it is possible to obtain the corrected LPP phase difference for correction using the correlation expression shown in Expression (C), for example.

Correction value = address increase rate after change × LPP phase difference / address increase rate (C) Since the above correlation information only needs to be stored once,
A system in which the correlation information is acquired only in the first adjustment step may be used. For the same reason, the main beam LP
The P signal detection means 16 and the LPP phase difference detection means 17 may be configured outside the optical disk device.

Next, the phase difference correcting means 15 corrects the phase of the sub-beam LPP signal (q) detected by the sub-beam LPP signal detecting means 14 by the corrected LPP phase difference correlated with the equation (C). Then, an LPP signal having the same phase as the main beam LPP signal (p) is obtained.

As described above, by extracting the sub-beam LPP signal (q), it is possible to extract the sub-beam LPP signal which is not affected by the recording mark or the recording pulse even during the recorded disc or during recording. Further, by performing the phase correction of the sub-beam LPP signal (q), the LPP signal equivalent to the main beam LPP signal (p) can be extracted even when the rotation speed of the optical disc 1 changes.

In each of the above-mentioned embodiments, the inner side sub-beam and the outer side sub-beam are arranged with respect to the main beam by shifting the main beam toward the inner side and the outer side by a half track pitch with respect to the track. However, the focus control, the tracking control, and the L control described in each of the above-described embodiments have been described.
The position is not limited to the above half track pitch difference as long as the PP signal extraction operation is possible.

[0100]

As described above, according to the present invention, when the LPP signal of the recorded disc is extracted, the sub-beam detection signal obtained from the sub-beam which follows the land portion where the LPP of the optical disc is formed. A sub-beam LPP signal is extracted from the sub-beam and the LPP signal is extracted by correcting the phase difference caused by the displacement of the sub-beam LPP signal on the information recording surface of the main beam and the sub-beam. When the signal is extracted, the gain is changed according to the amplitude of the recording pulse and then the phase difference is corrected to obtain L
The PP signal can be extracted.

Therefore, the LPP from the recorded disc
When extracting the signal and the LPP signal during recording on the disc, it is affected by the change in the recording power due to the recording mark or the recording pulse during recording, the change in the reflectance of the information recording surface that occurs when the recording mark is generated, and the like. It is possible to extract an LPP signal having no noise component and having an accurate phase with respect to the recording mark.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an optical disc device according to a first embodiment of the present invention.

FIG. 2 is a waveform diagram showing an operation in the optical disc device according to the first embodiment.

FIG. 3 is a block diagram showing a schematic configuration of an optical disc device according to a second embodiment of the present invention.

FIG. 4 is a waveform diagram showing an operation in the optical disc device according to the second embodiment.

FIG. 5 is a block diagram showing a schematic configuration of an optical disc device according to a third embodiment of the present invention.

FIG. 6 is a waveform diagram showing an operation in the optical disc device according to the third embodiment.

FIG. 7 is a block diagram showing a schematic configuration of an optical disc device according to a fourth embodiment of the present invention.

FIG. 8 is a waveform chart showing an operation in the optical disc device according to the fourth embodiment.

FIG. 9 is a block diagram showing a schematic configuration of a conventional optical disc device.

FIG. 10 is a schematic diagram showing a structure of an information recording surface of an optical disc which has been conventionally used in an optical disc device and an arrangement of light spots irradiated on the information recording face.

FIG. 11 is a waveform diagram showing the operation of the conventional optical disc device.

[Explanation of symbols]

1 optical disc 2 rotation drive means 3 Laser oscillation means 4 Laser spectroscopic means 5 Light spot forming means 6 Light spot detection means 7 Main beam detection means 8 Inner circumference side sub-beam detection means 9 Outer side sub-beam detection means 10 Servo signal generating means 11 Servo means 12 Drive means 13 Gain switching means 14 Sub-beam LPP signal detecting means 15 Phase difference correction means 16 Main beam LPP signal detecting means 17 LPP phase difference detection means 18 Wobble period detection means 19 Wobble Period LPP Phase Difference Correlation Means 20 LPP cycle detecting means 21 LPP Cycle LPP Phase Difference Correlation Means 22 Sub-beam LPP address acquisition means 23 Address increase rate calculation means 24 Address increase rate LPP phase difference correlation means 25 LPP component maximum value detection means 26 Wobble signal detecting means 27 Wobble signal maximum value detection means 28 LPP slice level determination means 29 Comparator 30 push-pull signal generation means

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Claims (15)

[Claims] 1. A rotation drive means for rotating and driving an optical disc having pits formed at predetermined intervals between tracks concentric or spiral on an information recording surface and formed by wobbling grooves, and outputs a laser. Based on the laser oscillation means and the laser, a main beam that follows the track, and at least one or more sub-beams that are shifted from the main beam in a direction perpendicular to the track are generated, and those beams are optically generated. Spot forming means for forming a light spot corresponding to the main beam and the sub beam on the information recording surface, and a main beam detecting means for detecting the light spot of the main beam reflected from the information recording surface. And at least detecting the light spot of the sub-beam reflected from the information recording surface. Also, one or more sub-beam detecting means, servo signal generating means for generating a servo signal from the detection signals of the main beam detecting means and the sub-beam detecting means, and drive control of the light spot forming means from the servo signal. Servo means for generating a control signal and drive means for driving the light spot forming means by the control signal are provided, and information is recorded on the optical disc while the light spot forming means is driven by the drive means. In the optical disc device that generates the land pre-pit (LPP) signal corresponding to the pit between the tracks in order to obtain the information of the target address when reproducing, the sub-beam detection signal detected by the sub-beam detection means is used. Sub beam for obtaining LPP signal Sub beam for detecting LPP signal Provided beam LPP signal detecting means, on the basis of the sub-beam LPP signal, the optical disc apparatus characterized by being configured to generate the LPP signal. 2. A push-pull signal generation means for generating a push-pull signal from the main beam detection signal detected by the main beam detection means, and a main beam LPP signal detection means for detecting a main beam LPP signal from the push-pull signal. And the LP generated between the sub beam LPP signal and the main beam LPP signal.
2. The optical disk device according to claim 1, further comprising a phase difference correction means for correcting the P phase difference to generate the LPP signal. 3. The sub-beam LPP by switching the gain for the sub-beam detection signal detected by the sub-beam detection means according to the recording power during information recording.
3. The optical disk device according to claim 1, further comprising a gain switching means for supplying the signal detecting means. 4. A rotation driving means for rotating and driving an optical disk having pits formed at predetermined intervals between tracks concentric or spiral on an information recording surface and formed by wobbling grooves, and outputting a laser. Based on the laser oscillation means and the laser, a main beam that follows the track, and at least one or more sub-beams that are shifted from the main beam in a direction perpendicular to the track are generated, and those beams are optically generated. Spot forming means for forming a light spot corresponding to the main beam and the sub beam on the information recording surface, and a main beam detecting means for detecting the light spot of the main beam reflected from the information recording surface. And at least detecting the light spot of the sub-beam reflected from the information recording surface. Also, one or more sub-beam detecting means, servo signal generating means for generating a servo signal from the detection signals of the main beam detecting means and the sub-beam detecting means, and drive control of the light spot forming means from the servo signal. Servo means for generating a control signal and drive means for driving the light spot forming means by the control signal are provided, and information is recorded on the optical disc while the light spot forming means is driven by the drive means. In order to obtain the information of the target address when reproducing, to obtain the LPP signal from the sub-beam detection signal detected by the sub-beam detection means in the optical disc device that generates the LPP signal corresponding to the pits between the tracks. Sub-beam LPP signal detection hand for detecting sub-beam LPP signal When the main detected by the beam detector means from the main beam detection signal and the push-pull signal generating means for generating a push-pull signal, the main beam LP from the push-pull signal
A main beam LPP signal detecting means for detecting a P signal,
LP for detecting an LPP phase difference between the sub-beam LPP signal and the main beam LPP signal.
P phase difference detection means, wobble cycle detection means for detecting a wobble cycle from the servo signal generated by the servo signal generation means, and wobble cycle LPP phase difference correlation means for correlating the wobble cycle with the LPP phase difference. Based on the correlation by the wobble cycle LPP phase difference correlating means, phase correction is performed based on the wobble cycle so that the sub beam LPP signal has no phase difference from the main beam LPP signal, and LPP An optical disk device, which is configured to generate a signal. 5. The optical disk device according to claim 4, wherein the wobble period LPP phase difference correlation means is configured to perform correlation using a period ratio for the LPP phase difference based on the wobble period. 6. The wobble cycle LPP phase difference correlation means uses the correlation equation (correction value = wobble cycle after change × LPP phase difference ÷ wobble cycle) to determine the correlation between the wobble cycle and the LPP phase difference. The optical disk device according to claim 4 or 5, wherein the optical disk device is configured so as to take. 7. The sub-beam LPP by switching the gain for the sub-beam detection signal detected by the sub-beam detection means according to the recording power during information recording.
7. A gain switching means for supplying to the signal detecting means is provided, and claim 4 or claim 5 or claim 6 is provided.
The optical disk device described. 8. A rotation driving means for rotating and driving an optical disc having pits formed at a predetermined interval between tracks concentric or spiral on an information recording surface and formed by wobbling grooves, and outputs a laser. Based on the laser oscillation means and the laser, a main beam that follows the track, and at least one or more sub-beams that are shifted from the main beam in a direction perpendicular to the track are generated, and those beams are optically generated. Spot forming means for forming a light spot corresponding to the main beam and the sub beam on the information recording surface, and a main beam detecting means for detecting the light spot of the main beam reflected from the information recording surface. And at least detecting the light spot of the sub-beam reflected from the information recording surface. Also, one or more sub-beam detecting means, servo signal generating means for generating a servo signal from the detection signals of the main beam detecting means and the sub-beam detecting means, and drive control of the light spot forming means from the servo signal. Servo means for generating a control signal and drive means for driving the light spot forming means by the control signal are provided, and information is recorded on the optical disc while the light spot forming means is driven by the drive means. In order to obtain the information of the target address when reproducing, to obtain the LPP signal from the sub-beam detection signal detected by the sub-beam detection means in the optical disc device that generates the LPP signal corresponding to the pits between the tracks. Sub-beam LPP signal detection hand for detecting sub-beam LPP signal When the main detected by the beam detector means from the main beam detection signal and the push-pull signal generating means for generating a push-pull signal, the main beam LP from the push-pull signal
A main beam LPP signal detecting means for detecting a P signal,
LP for detecting an LPP phase difference between the sub-beam LPP signal and the main beam LPP signal.
P phase difference detecting means and L based on the sub beam LPP signal detected by the sub beam LPP signal detecting means
LPP cycle detecting means for detecting a PP cycle and the LPP
LPP cycle LP that correlates the cycle and the LPP phase difference
P phase difference correlation means is provided, and based on the correlation by the LPP cycle LPP phase difference correlation means, the phase is adjusted based on the LPP cycle so that the sub beam LPP signal has no phase difference from the main beam LPP signal. Correct, L
An optical disc device configured to generate a PP signal. 9. The LPP cycle LPP phase difference correlation means is configured to perform correlation by using a cycle ratio for the LPP phase difference based on the LPP cycle.
The optical disk device described. 10. The LPP cycle and the LP using the correlation equation (correction value = LPP cycle after change × LPP phase difference ÷ LPP cycle) in the LPP cycle LPP phase difference correlation means.
The optical disk device according to claim 8 or 9, wherein the optical disk device is configured to have a correlation with a P phase difference. 11. A sub-beam LP is obtained by switching a gain for a sub-beam detection signal detected by the sub-beam detection means according to a recording power during information recording.
11. An optical disk device according to claim 8, 9 or 10, further comprising a gain switching means for supplying the P signal detecting means. 12. An optical disc having pits formed at predetermined intervals between tracks formed by wobbling grooves, which are concentric or spiral on an information recording surface,
Rotational driving means for rotationally driving, laser oscillating means for outputting a laser, a main beam that follows the track based on the laser, and at least one of which is shifted from the main beam in a direction perpendicular to the track. Light spot forming means for forming the above-mentioned sub-beams, optically converging those beams, and forming light spots corresponding to the main beam and the sub-beams on the information recording surface; Main beam detecting means for detecting the light spot of the main beam, at least one or more sub beam detecting means for detecting the light spot of the sub beam reflected from the information recording surface, the main beam detecting means and the sub beam detecting means Servo signal generating means for generating a servo signal from the detection signal of A servo means for generating a control signal for driving and controlling the light spot forming means from a servo signal; and a driving means for driving the light spot forming means in response to the control signal. In the optical disc device which generates an LPP signal corresponding to the pit between the tracks in order to obtain information of the target address when recording / reproducing information to / from the optical disc while driving the forming means, the sub beam detection is performed. A sub-beam LPP signal detecting means for detecting a sub-beam LPP signal for obtaining the LPP signal from the sub-beam detecting signal detected by the means, and a push for generating a push-pull signal from the main beam detecting signal detected by the main beam detecting means. Pull signal generating means and the push-pull signal Main beam LP
A main beam LPP signal detecting means for detecting a P signal,
LP for detecting an LPP phase difference between the sub-beam LPP signal and the main beam LPP signal.
P phase difference detection means, sub-beam LPP address acquisition means for acquiring address information of the sub-beam LPP signal detected by the sub-beam LPP signal detection means, and an increase rate of the sub-beam LPP address information within a predetermined time. The address increase rate calculation means for obtaining the address increase rate and the address increase rate LPP phase difference correlation means for correlating the address increase rate and the LPP phase difference are provided, and the correlation by the address increase rate LPP phase difference correlation means is provided. Based on the address increase rate, the sub-beam LPP signal is phase-corrected so that there is no phase difference from the main beam LPP signal, and the LPP signal is generated. apparatus. 13. The address increase rate LPP phase difference correlation means is configured to perform correlation using a ratio of the LPP phase difference to the cycle based on the address increase rate obtained from the sub-beam LPP signal. The optical disk device according to claim 12. 14. The address increase rate LPP phase difference correlation means is defined by a correlation equation (correction value = address increase rate after change × L).
14. The optical disk device according to claim 12 or 13, wherein a correlation between the address increase rate and the LPP phase difference is obtained by using (PP phase difference / address increase rate). 15. The gain of the sub-beam detection signal detected by the sub-beam detection means is switched according to the recording power during information recording, and the sub-beam LP is changed.
15. The optical disk device according to claim 12, claim 13 or claim 14, further comprising gain switching means for supplying the P signal detecting means.