JPH09161322A - Optical disk and optical disk recording and reproducing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable stable tracking control by differently setting the ratio between widths of a land and a groove and recording information on the signal tracks of the land and the groove the ratio of whose widths is set differently. SOLUTION: An optical disk 21 is provided with the structure of the disk capable of detecting a tracking control signal of the period of the land or the groove, and by making the jumping distance doubled, the probability of jumping due to a disturbance, etc., is reduced remarkable. That is, if the distance is doubled, the probability of jumping for the same disturbance is reduced to e<2> times. Further, since the jumping is performed from the signal track of the land (groove) to the signal track of the land (groove), and is performed before or after one revolution of the same signal track, the stable tracking control is made possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a recording control optical disc having a land / groove structure with a proper land / groove width ratio so that a tracking control signal is cycled at the land or groove cycle. The present invention relates to an optical disc and an optical disc recording / reproducing apparatus that have good performance and stably control tracks of a read-only disc and a recordable disc.

[0002]

2. Description of the Related Art Generally, a recordable optical disc has a signal track having a structure of a land and a groove, and enables tracking control even on an empty disc on which no information signal is recorded. Recently, in order to increase the recording density, information signals are recorded on the land and groove tracks, respectively. Therefore, the wavelength of the laser light of the optical pickup for recording / reproducing is shortened, the numerical aperture of the objective lens for condensing is increased, and the size of the light beam for recording / reproducing is reduced. Incidentally, the crosstalk signal mixed in the adjacent signal tracks is reduced by the signal processing, and the distance between the signal tracks, that is, the signal track pitch is reduced in order to increase the recording density. The spiral track structure is suitable for recording / reproducing a large amount of continuous information such as voice or image information. In this way, the distance between the signal tracks becomes shorter as the density becomes higher, and in order to record the signals on the land tracks and the groove tracks, the land and groove width ratios are made the same.

That is, as shown in FIG. 1, in an optical disk having a land and groove structure, signal tracks for recording information signals are placed at the centers of the land and groove tracks, and the distance between the signal tracks, that is, the track pitch is Tp. And the land width Wl and the groove width W
g, and the land period and the groove period are the same and Lp, the land ratio Rl is Rl = Wl / Lp = Wl / (Wl + Wg) = 1-Rg (1), and the groove ratio Rg Is Rg = Wg / Lp = 1-Rl (2), and the groove period Lp is Lp = Wl + Wg (3). At this time, the width of the land and the groove should be the same and R
Set l = 0.5.

For tracking control for tracking a signal track when recording or reproducing on such a disc with an optical pickup, a reproduced tracking control signal Te, which represents the position of a condensed light beam, that is, The tracking control signal that changes depending on the distance that the light beam to be recorded or reproduced deviates from the signal track is
As shown in FIG. 2, the land or groove period L
It changes at a period of a signal track pitch Tp, which is a half distance of p, that is, a distance between signal tracks for recording signals at the track centers of the land and the groove. At this time, in the detected tracking control signal Te, the signal track pitch T
has a periodicity of p (half the land period Lp),
It becomes impossible to distinguish whether the light beam is on the land signal track or the groove signal track.

Then, as shown in FIG. 2, the tracking control signal is zero at the center of the land signal track or the groove signal track, but the tracking control signal is accurately positioned at the center. It can be seen that the polarity of the control signal has changed and it is off to the left and right of the signal track. The absolute value of the tracking control signal becomes maximum when the light beam comes between the signal tracks.

Since the tracking control signal Te changes in the cycle of the signal track pitch Tp as described above, when the track is crossed by a disturbance such as an external impact or electric noise, when the signal track pitch Tp becomes small, the phenomenon of crossing between the signal tracks will occur. Is more likely to occur, and when the land (groove) signal track is tracked, the signal can be jumped over to the groove (land) signal track due to a disturbance, which causes a problem that the tracking cannot be controlled accurately.

On the other hand, in a read-only optical disk such as a compact disk (CD), since an information signal is recorded in continuous groove pits in a spiral signal track, in order to reproduce the recorded information. Tracks and controls a laser beam focused by an optical pickup according to a signal pit to read and reproduce an information signal. A digital video disc (DVD: Digital
In a high-density optical disc for reproduction such as a video disc), the distance between signal tracks, that is, the signal track pitch and the size of a signal pit are reduced in order to increase the recording density.
As a result, the reproduction sensitivity is poor and the influence of laser light or disk noise is strong.

At this time, in order to weakly affect the influence of the laser light or the noise of the disk, the reproduction is performed by setting the depth of the signal pit to 0.25 wavelength (the wavelength of the laser light used for the optical pickup to be reproduced). However, the tracking control signal is not detected by the push-pull method.

The high-density disc has a two-layer structure in order to increase the recording capacity of the disc.
Beam type tracking control is difficult. Therefore, a reproducing apparatus for a high density disc such as a DVD adopts a phase difference detection method in order to obtain a tracking control signal. The phase difference detection method detects the tracking control signal by the reproduction signal of the recorded signal pits, so it is not affected by the tilt of the disc and the asymmetry of the light distribution in the aperture of the objective lens of the optical pickup. To get

FIG. 3 is a general block diagram of a read-only disc reproducing apparatus such as a CD or DVD. According to FIG. 3, a read-only optical disc 11, an optical pickup 12 that projects light onto the optical disc 11 and senses reflected light, and a light stabilizer 13 that stabilizes the generation of laser light by the optical pickup 12. , A focus control signal generator 14 which receives an electric signal (a, b, c, d) output from the optical pickup 12 and (a + c)-(b + d) to generate a focus control signal Fe.
When the electric signals (a, b, c, d) output from the optical pickup 12 are received, a + c is applied to remove the direct current, and b + d is applied to remove the direct current, and then the phase difference between the two signals is detected. A tracking control signal generator 15 for generating a tracking control signal Te, and the optical pickup 1
2 is received from the electric signal (a, b, c, d) output from the device 2, and is a + b + c + d to generate a high frequency reproduction signal RF. A focus control unit 17 that controls the focus of the optical pickup 12 using the focus control signal Fe, and a tracking control unit that controls the tracking of the optical pickup 12 using the tracking control signal Te output from the tracking control signal generation unit 15. 18 and.

At this time, the optical pickup 12 includes a laser diode LD for generating laser light, a beam splitter BS for separating incident light and reflected light, and a beam splitter B.
Objective lens OL that focuses the beam projected from S onto the signal track of the optical disc 11, and a tracking driver TA that drives tracking and focus so that the objective lens OL can focus the beam onto the signal track of the optical disc 11. And a focus driver FA, a sensor lens SL for obtaining a focus control signal by the astigmatism method,
And a photodetector PD that detects the light reflected from the optical disk 11 and outputs it to the focus control signal generator 14, the tracking control signal generator 15, and the RF reproduction signal generator 16.

Here, as shown in FIG. 4, the photodetector PD for detecting the light quantity of the beam is divided into four in the signal track direction and the radial direction of the optical disk 11, that is, four divided areas.
It is composed of individual photodetector elements PDA, PDB, PDC, PDD. Then, the tracking control signal generator 1
Reference numeral 5 is a first summing amplifier 15- for additionally amplifying a and c signals output from the photodetector PD of the optical pickup 12.
1, a first capacitor C1 for removing the DC component of the a + c signal output from the first summing amplifier 15-1, and b, d output from the photodetector PD of the optical pickup 12.
A second summing amplifier 15-2 that sums and amplifies signals, a second capacitor C2 that removes the DC component of the b + d signal output from the second summing amplifier 15-2, and the first and second capacitors C1 and C2. A phase comparator 15-3 configured to compare the phase difference between the two signals RFt1 and RFt2 from which the DC component has been removed and detect the tracking control signal Te. Then, the focus control signal generator 14
The RF reproduction signal generator 16 can be configured by using a summing amplifier.

In the configuration shown in FIG. 3, the laser diode LD emits a laser beam under the control of the light stabilizing section 13 for turning the laser beam on and off by the system control signal, and the emitted laser beam is emitted from the beam splitter BS. It is reflected, condensed by the objective lens OL, and placed on a signal track formed by a pit row of grooves of the disk 11.

The light reflected from the signal recording surface of the disk 11 on which the information signal is recorded is condensed by the objective lens OL, passes through the beam splitter BS, and is condensed by the sensor lens SL. The signal is read by detecting with a photodetector PD as shown in FIG.

At this time, the photodetector PD outputs the electric signals a, b, c, d proportional to the amount of light obtained from the respective photodetector elements (PDA, PDB, PDC, PDD) to the focus control signal generator 14. , Tracking control signal generator 1
5 and the RF reproduction signal generator 16. The focus control signal generator 14 includes the optical pickup 12
Electrical signals a, b, c, d output from the photodetector PD of
Is added to (a + c)-(b + d) to generate a focus control signal Fe, which is output to the focus control unit 17.

The focus controller 17 processes the generated focus control signal Fe to drive the focus driver FA of the optical pickup 12 to control the focus. The tracking control signal generator 15 receives the electric signals (a, b, c, d) output from the photodetector PD of the optical pickup 12 as a first summing amplifier 15-1.
A + c by the first capacitor C1 to remove the DC component (RFt1), and the second summing amplifier 15-2 b + d, and then the second capacitor C2 to remove the DC component (RFt2) to perform phase comparison. It outputs to each device 15-3. The phase comparator 15-3 detects the tracking control signal Te by comparing the phase difference between the two signals RFt1 and RFt2 from which the DC component has been removed.

The tracking controller 18 processes the tracking control signal Te detected by the phase comparator 15-3 to drive the tracking driver TA of the optical pickup 12 to control the tracking. The RF reproduction signal generator 16 a + b + c + d the electric signals a, b, c and d output from the photodetector PD of the optical pickup 12 by a summing amplifier to generate a high frequency reproduction signal RF. The high frequency reproduction signal RF generated from the RF reproduction signal generator 16 can obtain information recorded by digital signal processing. Here, the reproduced digital information data is variously processed according to the purpose.
At this time, the tracking control signal Te detected by the phase difference detection method is a triangular wave signal which is converted at the cycle of the signal track as shown in FIG.

Therefore, in the recording / reproducing apparatus for recording and reproducing information on the optical disc having the structure of the land and the groove, there is a problem that the tracking control signal cannot be detected by the phase difference detecting method as described above. That is, in a disc on which no groove pit signal or mark signal is recorded (for example, an empty disc), signal pits (marks) are not continuously formed, and a tracking control signal is generated in the phase difference detection method. Not detected. Therefore, in a recording / reproducing apparatus that records and reproduces an optical disk having a land and groove structure, the tracking control signal is detected by the push-pull method to control the tracking. However, the recording / reproducing device that detects the tracking control signal by the push-pull method is not suitable for reproducing a reproduction-only disc. That is, when the push-pull method is used when reproducing a reproduction-only disc, the tracking control signal is distorted due to the inclination of the disc, that is, the tilt of the disc, so that proper tracking control cannot be performed.

Therefore, in order to reproduce the reproduction-only disc, it is necessary to perform the tracking control by another method, for example, the phase difference detection method as shown in FIG. 3 so that the reproduction-only disc can be reproduced. In a recording / reproducing apparatus that simultaneously reproduces a disc having a large difference in track pitch, such as a high-density disc such as a DVD and a low-density disc such as a CD, the 3-beam type tracking control is not suitable. The 3-beam method is not suitable for reproducing a high-density disc having a layered structure. That is, the tracking control signal must be detected by the phase difference detection method in order to simultaneously reproduce a high density disc such as a DVD and a low density disc such as a CD.

[0020]

As described above, since the recordable disc recording / reproducing apparatus controls the tracking by the push-pull method, the tracking of the reproduction-only disc cannot be controlled, and the reproduction-only disc reproducing apparatus cannot Since the tracking is controlled by the phase difference detection method, the tracking of the recordable disc cannot be controlled. Therefore, conventionally, there is a problem in that it is not possible to simultaneously reproduce a read-only disk such as a CD or a DVD and a recordable disk having a land and groove structure by using one optical disk recording / reproducing apparatus.

The present invention is intended to solve such a problem, and an object thereof is to provide an optical disc in which a tracking control signal has a periodicity in the cycle of the land or the groove by making the width ratio of the land and the groove different. To do.

Another object of the present invention is to track only a land track or a groove track by appropriately adjusting the width ratio of the land and the groove so that the tracking control signal has periodicity in the land or groove cycle. In this way, it is an object of the present invention to provide an optical disk recording / reproducing apparatus that reduces track crossing due to disturbance or the like and stably controls a land track and a groove track.

Another object of the present invention is to detect a phase difference when a recorded signal among the tracking control signals detected by the push-pull method causes a larger sensitivity difference when recording and reproducing a recordable optical disk. Tracking is controlled by compensating with the tracking control signal detected by the method, tracking is controlled by the phase difference detection method when a read-only disc is played, and tracking is performed by the push-pull method when recording on an empty disc. It is an object of the present invention to provide an optical disc recording / reproducing apparatus that stably controls tracking of a recordable disc and a read-only disc by one optical disc recording / reproducing device.

[0024]

An optical disk according to the present invention comprises a land structure and a groove structure.
In an optical disc having signal tracks for recording information signals on lands and grooves, the land and groove width ratios are set differently, and information is recorded on the land and groove signal tracks whose width ratios are set differently. By doing so, the tracking control signal of the land or groove cycle can be detected, and the above-mentioned object is achieved thereby.

In one embodiment, the optical disk is a magneto-optical disk whose reflectance does not change, and the width ratio of the lands or grooves is 0.6 or more and 0.8 or less.

In one embodiment, the optical disc is a disc on which an information signal is recorded by changing the reflectance, and the ratio of the widths of lands or grooves is 0.635 or more and 0.8 or less.

The optical disk recording / reproducing apparatus according to the present invention comprises:
In an apparatus for recording / reproducing an optical disk having a land and groove structure and having signal tracks for recording information signals in the land and the groove, an optical disk in which the width ratio of the land and the groove is set to a predetermined ratio, and the optical disk. An optical pickup that records and reproduces information on the
A reproduction signal processing unit that receives an electric signal output from the optical pickup to detect a focus control signal, a tracking control signal, and a high frequency reproduction signal, and an optical signal using a focus control signal output from the reproduction signal processing unit. Focus control means for controlling the focus of the pickup and tracking control signal output for directly or inverting and amplifying the tracking control signal output from the reproduction signal processing means according to the tracking of the land signal track or the groove signal track. And a tracking control means for controlling the tracking of the optical pickup by using the tracking control signal output from the tracking control signal output means, thereby achieving the above object.

In one embodiment, the tracking control signal output means comprises a plurality of resistors and a differential amplifier connected in series and parallel, and the tracking control signal output from the reproduction signal processing means is inverted and amplified to a predetermined gain. Inverting amplification section, an empty disc, a first switching section for controlling the amplification gain of the inverting amplification section in order to compensate for the difference in sensitivity of detection signals in the signal recorded disc, and a land signal track or groove. A second switching circuit for selectively outputting the tracking control signal of the reproduction signal processing means or the tracking control signal of the inverting amplifier to the tracking control means.
It is composed of a switching unit.

In one embodiment, the first switching unit controls the amplification gain of the optical disc for recording the information signal by changing the reflectance.

In one embodiment, the first switching unit controls the inverting amplification unit so that the amplification gain of the tracking control signal of the disc on which the signal is recorded is larger than that of the blank disc.

In one embodiment, the first switching unit fixes the amplification gain of the disk having no change in reflectance.

The optical disk recording / reproducing apparatus according to the present invention comprises:
In an apparatus for recording / reproducing an optical disc having a structure of lands and grooves and having signal tracks for recording information signals on the lands and grooves respectively, an optical disc in which the width ratio of lands and grooves is set to a predetermined ratio An optical pickup that generates a main beam for reading and an auxiliary beam for tracking detection to record and reproduce information on the optical disc, and an input of an electric signal output from the optical pickup in proportion to the light amount of the main beam. A reproduction signal processing means for receiving a focus control signal and a high frequency reproduction signal, receiving an electric signal output from the optical pickup in proportion to the light quantity of the auxiliary beam and detecting a tracking control signal, and the reproduction signal. The focus of the optical pickup is controlled using the focus control signal output from the processing means. Focus control means, tracking control signal output means for outputting a tracking control signal output from the reproduction signal processing means directly or by inversion according to tracking of a land signal track or a groove signal track, and the tracking control And a tracking control means for controlling the tracking of the optical pickup by using the tracking control signal output from the signal output means, whereby the above object is achieved.

In one embodiment, the tracking control signal output means comprises a plurality of resistors and a differential amplifier having an amplification gain of 1, and an inverting amplification section for inverting the tracking control signal output from the reproduction signal processing means. When,
And a switching unit which is switched according to the tracking of the land signal track or the groove signal track and selectively outputs the tracking control signal of the reproduction signal processing unit or the tracking control signal of the inverting amplification unit to the tracking control unit. .

In one embodiment, the main beam for reading the information signal from the optical pickup is arranged at the center of the signal track to be tracked, and the auxiliary beam for detecting the tracking control signal is respectively tracked from the signal track to the left and right. The land is arranged at a position corresponding to 0.25 of the cycle so that it can be mounted on the track of the optical disk.

The optical disk recording / reproducing apparatus according to the present invention comprises:
A land / groove width ratio is set differently, and a disc capable of inserting information into the land / groove signal track with the width ratio set is provided, and a land or groove tracking control signal is applied during signal reproduction of the disc. The detection is performed and the tracking control is performed, which achieves the above object.

The optical disk recording / reproducing apparatus according to the present invention comprises:
From the optical pickup, a disc in which information is masked on the land and groove signal tracks in which the land and groove ratios are set differently and the width ratio is set, and an optical pickup for reading the masked information in the disc Reproduction signal processing means for receiving the input of the output information signal and detecting the tracking control signal, and tracking for outputting the tracking control signal output from the reproduction signal processing means as the tracking control signal having the cycle of the width of the land or groove. It includes a control signal output means and a tracking control means for performing tracking based on the tracking control signal output from the tracking control signal output means, whereby the above object is achieved.

The optical disk recording / reproducing apparatus according to the present invention comprises:
An optical pickup for recording / reproducing information on the optical disc by a laser beam; and first and second tracking error detecting means for receiving an electric signal output from the optical pickup and detecting tracking errors by different detection methods. , The type of the optical disk is discriminated by inputting the electric signal of the optical pickup, and the tracking is controlled by the detection output of the first tracking error detection means or the detection output of the second tracking error detection means according to the discrimination result. And a control means for achieving the above object.

In one embodiment, the first tracking error detecting means detects a tracking error by a phase difference detecting method.

In one embodiment, the second tracking error detecting means detects a tracking error by a push-pull detection method.

The optical disk recording / reproducing apparatus according to the present invention comprises:
An optical pickup that records and reproduces information on an optical disk by a laser beam, a tracking control signal output unit that receives an electric signal of the optical pickup and detects tracking control signals by different detection methods, and an electric signal of the optical pickup. A control unit that determines the type of the optical disc as an input and outputs a control signal according to the determination result, and a tracking control that performs tracking with a tracking control signal that is selectively output from the tracking control signal output unit according to the control of the control unit. And a control means for achieving the above object.

In one embodiment, the tracking control signal output means detects the tracking control signal by a phase difference detection method and a push-pull detection method.

In one embodiment, the tracking control means controls tracking with a tracking control signal detected by a phase difference detection method when reproducing a reproduction-only disc.

In one embodiment, the tracking control means controls tracking with a tracking control signal detected by the push-pull detection method when recording on an empty disc.

In one embodiment, when the recorded disc is reproduced or re-recorded, the tracking control means further increases the sensitivity difference due to the recorded signal of the tracking control signals detected by the push-pull method. The tracking control is performed by compensating for the other with the tracking control signal detected by the phase difference detection method.

In one embodiment, the tracking control signal output means uses the push-pull method to control the electric signals (a, b, c, d) output from the optical pickup by (a + d)-(b + c). The electric signal (a, b, c, d) output from the first tracking control signal generator for detecting the signal and the optical pickup is a + c.
Of the second tracking control signal generator for detecting the tracking control signal by comparing the phase difference between the two signals after removing the direct current and b + d for removing the direct current. The difference between the output and the output of the second tracking control signal generator is amplified to compensate for the sensitivity of the recordable / reproducible optical disc controlled by the tracking control signal detected by the push-pull method from the first tracking control signal generator. In order to reverse the polarity of the tracking control signal when tracking the signal track of the amplifier and the land, and when tracking the signal track of the groove,
In the case of a read-only disc or a recordable / reproducible disc, an inverting amplifier for inverting and amplifying the tracking control signal output from the amplifier is switched according to the land signal track or the groove signal track tracking, and the second tracking The control unit includes a tracking control signal of the control signal generation unit, a tracking control signal of the amplification unit, and a switching unit that selectively outputs the tracking control signal of the inverting amplification unit.

In one embodiment, the second tracking control signal generating section includes a first summing amplifier that sums and amplifies the a and c signals output from the optical pickup, and the first summing amplifier.
A first capacitor that removes the DC component of the a + c signal output from the summing amplifier, a second summing amplifier that sums and amplifies the b and d signals output from the optical pickup, and b + d that is output from the second summing amplifier. It is composed of a second capacitor for removing the DC component of the signal and a phase comparator for detecting the tracking control signal by comparing the phase difference between the two signals from which the DC components have been removed by the first and second capacitors.

[0047]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

First Embodiment In the first embodiment of the present invention, the optical disc has a disc structure capable of detecting a tracking control signal having a land or groove period, and the jump distance is doubled. As a result, the possibility of jumping due to disturbance or the like is extremely reduced. That is, when the distance doubles,
The probability of jumping over the same disturbance is reduced by a factor of e ² .
In addition, the signal track of the land (groove) is crossed over to the signal track of the land (groove) and the
Stable tracking control is possible because the speed is exceeded before or after rotation.

FIG. 6 is a signal waveform diagram showing the change of the tracking control signal due to the change of the land width ratio of the present invention, which is detected by the disk with different land and groove width ratios. To the tracking control signal Te, the land cycle Lp (signal track pitch T
signal component having 2 times p),
The tracking control signal Te detected by changing the land width ratio R1 is changed. At this time, as shown in FIG. 6, the greater the difference in width between the land and the groove, the more clearly the land period Lp is represented.

That is, when the land and groove have the same width and the land ratio Rl is closer to 0.5, the sine wave signal of the signal track period becomes stronger, and the land ratio is larger than 0.5. The larger the value, the stronger the triangular wave signal component of the land period becomes, and the land ratio Rl becomes 0.6.
Then, the detection sensitivity of the tracking control signal in the land signal track becomes zero. And Rl is 0.6
If it is larger, the polarity of the detection signal is inverted with respect to the detection signal when Rl is 0.5, which is half the cycle of the land, and the polarities of the detection signals are opposite on the left and right, and Since the polarities of the signals are the same within the half cycle, the tracking control can be performed in the land cycle. When the land ratio R1 becomes 0.8, the sensitivity of the control signal detected from the land signal track becomes maximum, and when it becomes 0.8 or more, the sensitivity decreases and the width of the groove becomes narrow, resulting in a decrease in the recording track. It does not fit because the width of is narrow.

As can be seen from FIG. 6, the land width ratio Rl
When 0.8 is set to 0.8, the polarity changes for the land signal track and the detection sensitivity is the same, but the polarity remains the same for the groove signal track, but the detection sensitivity increases three times or more. . Therefore, when the tracking control for tracking the land and groove signal tracks is performed on such a disc, the polarity of the control signal is set to the opposite when the land track control is performed with respect to the control for the groove tracks, and three times or more. The control of the land track and the groove track can be made equal by controlling with the control signal amplified to.

On the other hand, when the width of the groove is wider than the width of the land and the ratio Rg of the width of the groove is larger than 0.5, it is the same as when the width of the land is widened with respect to the track of the groove. The polarity of the detection signal changes with respect to the signal track No., the tracking signal of the land track keeps the same polarity, and the signal detection gain increases three times or more.

FIG. 6 shows the case of an optical disk in which the signal is not recorded or the reflectivity does not change greatly even when a signal is recorded, such as a magneto-optical disk, and the land or groove ratio Rl or Rg is 0. A tracking control signal having a land (groove) cycle can be obtained by setting the value larger than 0.6. However, in an optical disc such as a phase conversion disc that records by changing the reflectance, when a signal is recorded, the value of the detected tracking control signal changes.

FIG. 7 is a waveform diagram of the tracking control signal in the optical disc on which the information signal according to the present invention is recorded. The reflectance of the recording signal pit with respect to the reflecting surface of the disc is 0.35, and the signal is The change of the tracking signal detected when the ratio Rl of the land of the recorded disc is changed is shown. That is, FIG.
It shows that when the land ratio becomes larger, the signal polarity does not change within half a year, and the land width ratio must be 0.65 or more. The signal for the groove shows almost no change, but the detection sensitivity of the tracking signal is reduced in the land.
Therefore, in the phase conversion disc, tracking control should be performed separately for the recorded disc and the blank disc, and when controlling the disc on which the information signal is recorded, the tracking control gain should be set higher than that of the blank disc. Good.

Second Embodiment FIG. 8 is a block diagram of a one-beam type optical disk recording / reproducing apparatus according to a second embodiment of the present invention. The optical disk 21 has a land or groove ratio set to a predetermined ratio.
An optical pickup 22 for recording and reproducing information on the optical disc 21, an optical stabilizer 23 for stabilizing the generation of the laser light of the optical pickup 22, and an electric signal (a, b) output from the optical pickup 22. , C, d) to generate a focus control signal Fe by (a + c) − (b + d), a tracking control signal Te by (a + d) − (b + c), and a high frequency reproduction signal by a + b + c + d. A reproduction signal processing section 24 for generating RF, and a focus control signal F output from the reproduction signal processing section 24.
A focus control unit 25 for controlling the focus of the optical pickup 22 using e, and a tracking control signal Te output from the reproduction signal processing unit 24 along the land and groove signal tracks are directly or inverted amplified and output. A tracking control signal output unit 26, a tracking control unit 27 that controls tracking of the optical pickup 22 using the tracking control signal Te output from the tracking control signal output unit 26, the optical stabilizing unit 23, and a tracking control signal output. And a microcomputer MC which outputs a control signal to the unit 26.

Here, the optical disk 21 has a structure of lands and grooves, and there are signal tracks for recording information signals in the lands and the grooves, and the characteristics shown in FIGS. 6 and 7 are obtained depending on the width ratio of the lands. Yes, and set it to an appropriate value.

At this time, the optical pickup 22 includes a laser diode LD for generating laser light, a beam splitter BS for separating incident light and reflected light, and a beam splitter BS.
An objective lens OL for condensing a beam projected from the optical disc 21 on a signal track of the optical disc 21, and a tracking driver TA for driving tracking and focus so that the objective lens OL can condense the beam on the signal track of the optical disc 21. From a focus driver FA, a sensor lens SL for obtaining a focus control signal by the astigmatism method, and a photodetector PD which detects the light reflected from the optical disc 21 and enters the playback signal processing unit 24. Composed. Here, as shown in FIG. 4, the photodetector PD for detecting the light quantity of the beam has four photodetection elements PDA, PDB, PDC which are divided into four in the signal track direction and the radial direction of the optical disc 21. , PDD.

Then, the tracking control signal output section 26, when recording or reproducing the information signal on the signal track of the land wider than the groove, reproduces the signal processing section 24.
A series-parallel connected resistor R1, R2, R3 for inverting and amplifying the tracking control signal Te output from the differential amplifier A
An inverting amplifier 26-1 composed of MP1; a first switching element SW1 for changing an amplification gain by turning on / off a resistor R3 of the inverting amplification section 26-1 by a disc on which a signal is recorded or a blank disc; The second switching element SW2 is switched depending on whether the land signal track or the groove signal track is tracked and selectively outputs the output of the reproduction signal processing unit 24 or the inverting amplification unit 26-1. At this time, the control signal for switching the first and second switching elements SW1 and SW2 is output from the microcomputer MC. The reproduction signal processing section 24 can be configured by using a summing amplifier. Therefore, the reproduction signal processing unit 24
The tracking control signal output from is a signal detected by the push-pull detection method.

In the second embodiment of the present invention thus constructed, the light stabilizer 23 controls the light quantity of the laser diode LD of the optical pickup 22 based on the control signal output from the microcomputer MC. That is, in the recording state,
The amount of light is modulated by a recording signal that is modulated to be suitable for recording on the disk 21, so that the amount of light is constant during reproduction, and the amount of light is zero in the stopped state.

The laser light emitted from the laser diode LD is reflected from the beam splitter BS and condensed by the objective lens OL, and the condensed light beam is placed on the signal track of the optical disc 21 as shown in FIG. To be
The light reflected from the signal recording surface of the disc 21 on which the information signal is recorded is condensed again by the objective lens OL, passes through the beam splitter BS, and passes through the sensor lens SL.
The light is collected by and is incident on the photodetector PD.

The photodetector PD outputs electric signals a, b, c and d, which are proportional to the amount of light obtained from the respective photodetector elements PDA, PDB, PDC and PDD, to the reproduction signal processing section 24.

The reproduction signal processing section 24 uses the electric signal (a,
b, c, d) by (a + c)-(b +
d) to detect the focus control signal Fe, and (a + d)
The tracking control signal Te is detected by the push-pull detection method by-(b + c), and the high frequency reproduction signal RF is detected by a + b + c + d. At this time, the reproduction signal processing unit 24
The focus control signal Fe output from is input to the focus control unit 25 and subjected to signal processing, and then drives the focus driver FA of the optical pickup 22.

That is, the focus driver FA of the optical pickup 22 that drives the focusing objective lens OL up and down, that is, in the focus axis direction, keeps the distance between the objective lens OL and the optical disk 21 constant based on the focus control signal Fe. Keep and collect light optimally. Then, the reproduction signal processing unit 2
The RF reproduction signal (RF) output from 4 obtains information recorded by digital signal processing.

On the other hand, when recording or reproducing information on a signal track of a groove narrower than the land, that is, when tracking the signal track of the groove, the second switching element of the tracking control signal output section 26 is controlled by the microcomputer MC. SW2 is connected to the tracking control signal output terminal Te of the reproduction signal processing section 24. Therefore, the tracking control signal Te output from the reproduction signal processing unit 24 passes through the tracking control unit 27 and controls the tracking driver TA of the optical pickup 22.

That is, the tracking driver TA for driving the objective lens OL in the radial direction of the optical disk 21 drives the objective lens OL by the tracking control signal Te,
A light beam for recording or reproducing is placed at the center of the signal track of the groove.

On the other hand, when recording or reproducing on a signal track of a land wider than the groove, that is, when tracing a signal track of a land, the tracking control signal Te output from the reproduction signal processing section 24 is supplied to the inverting amplification section 26.
Invert and amplify at -1. At this time, the inverting amplifier 26-1
When the tracking control signal Te is inverted and amplified by, the amplification gain must be different depending on whether the signal is recorded on a blank disc or the recorded disc is reproduced.

That is, as shown in FIGS. 6 and 7, between the tracking control signal detected from an empty disc in which signal pits are not recorded and the tracking control signal detected from a disc having recorded signal pits. It can be seen that if a signal is recorded, the signal sensitivity of the land signal track drops significantly. Therefore, when recording on an empty disc with no signal pits recorded,
The first switching element SW is controlled by the microcomputer MC.
1 is turned on and the resistance values R1, R2, and R3 become (R2 // R
3) Make sure that / R1> 3. On the other hand, when reproducing a disc with recorded signal pits, the microcomputer MC
The first switching element SW1 is turned off by the control described above so that the resistance value becomes R2 / R1 >> 3, so that the amplification degree is made larger than that in the case of an empty disk.

That is, in the case of a disc which records an information signal by changing the reflectance, such as a phase conversion disc,
Since a disc on which a signal is recorded has a lower tracking signal detection sensitivity than an empty disc, the amplification gain is larger than that of an empty disc when the tracking control signal is inverted and amplified by the inverting amplifier 26-1 to compensate for this. Must.

Therefore, the output Te ^* of the inverting amplification section 26-1 which is output by changing the amplification degree by recording of an empty disc on which no signal is recorded or reproduction of the recorded disc is the second switching element SW2. And is output to the tracking control unit 27, and the tracking control unit 27 drives the tracking driver TA of the optical pickup 22 by processing the tracking control signal Te ^* to record or reproduce at the center of the land signal track. So that the light beam can be placed.

As described above, in the one-beam type tracking control signal detection method, since the tracking control signal is asymmetrical as shown in FIGS. 6 and 7, tracking is performed during tracking control of the land signal track and the groove signal track. The detection gain of the control signal is different.

In an optical disc which records an information signal by changing the reflectance like a phase conversion disc, the detection sensitivity of the tracking signal when the information signal is recorded is different from that when the information signal is not recorded. The detection gain of the tracking control signal is different for each case. However, when the tracking control signal is detected by the 3-beam method, the tracking control signal is detected symmetrically.

Third Embodiment FIG. 9 is a block diagram of a three-beam type optical disk recording / reproducing apparatus according to a third embodiment of the present invention. It shows an optical disk 31 having a land or groove width ratio set to a predetermined ratio. , An optical pickup 32 for recording and reproducing information on the optical disc 31, an optical stabilizer 33 for stabilizing the generation of laser light of the optical pickup 32, and an electric signal (a, b,) output from the optical pickup 32. c, d,
e, f) input, (a + c)-(b + d) to generate a focus control signal Fe, ef to generate a tracking control signal Te, and a + b + c + d to generate a high frequency reproduction signal RF. The signal processing unit 34 and the focus control signal Fe output from the reproduction signal processing unit 34
And a focus control section 35 for controlling the focus of the optical pickup 32, and a tracking control section for directly or inverting and outputting the tracking control signal Te output from the reproduction signal processing section 34 along the land and groove signal tracks. A signal output unit 36, a tracking control unit 37 that controls tracking of the optical pickup 32 using the tracking control signal Te output from the tracking control signal output unit 36, the optical stabilizing unit 33, and the tracking control signal output unit 36. And a microcomputer MC that outputs a control signal to

Here, the optical disc 31 has a structure of lands and grooves, and there are signal tracks for recording information signals in the lands and the grooves, and the width ratio of the lands is as shown in FIG. 6 or 7. Set. At this time, the optical pickup 32 causes a laser diode LD that generates a laser beam and a diffraction beam that passes a laser beam generated from the radar diode LD to a diffraction grating to form an auxiliary beam for detecting a tracking signal by a three-beam method. (Grating: GR), a beam splitter BS for separating incident light and reflected light, an objective lens OL for condensing the three beams projected from the beam splitter BS on a signal track of the optical disc 31, and an objective lens OL. , A tracking driver TA and a focus driver FA for driving tracking and focus so that the three beams can be focused on the signal track of the optical disc 31, and a sensor lens SL for obtaining a focus control signal by the astigmatism method.
And a photodetector PD ′ that detects the light reflected from the optical disc 31 and outputs it to the reproduction signal processing unit 34.

The photodetector PD 'is shown in FIG.
As shown in (b), it comprises a central light detecting element for detecting the light quantity of the main beam and an auxiliary light detecting element for detecting the light quantity of the auxiliary beam. The central light detecting element for detecting the light quantity of the main beam is a signal of the optical disc 31. Four photodetection elements (PDA, PD) divided into four in the track direction and the radial direction
B, PDC, PDD), and the auxiliary light detecting element for detecting the light quantity of the auxiliary beam is composed of two light detecting elements PDE, PDF respectively located at the upper end and the lower end of the central light detecting element.

Each of the photodetector elements PDA, PDB, PDC, PDD, of the photodetector PD 'thus constructed is
The PDE and PDF output electric signals corresponding to a, b, c, d, e, and f to the reproduction signal processing unit 34 to obtain the focus control signal Fe, the tracking control signal Te, and the high-frequency reproduction signal RF. To

The tracking control signal output section 36 reproduces the reproduced signal processing section 34 when recording or reproducing the information signal on the signal track of the land wider than the groove.
The tracking control signal Te output from the inverter R1 and R2 and the inverting amplifier 36-1 including the differential amplifier AMP1 and the land signal track or the groove signal track are switched to switch the reproduction signal. The switching unit SW1 selectively outputs the tracking control signal of the processing unit 34 or the tracking control signal of the inverting amplification unit 36-1.

At this time, the control signal L / G for switching the switching unit SW1 and the control signal output to the light stabilizing unit 33 are output from the microcomputer MC, and the reproduction signal processing unit 34 is configured by using an adding amplifier. can do.

In the third embodiment of the present invention constructed as described above, the light stabilizer 33 controls the light quantity of the laser diode LD of the optical pickup 32 based on the control signal output from the microcomputer MC.

That is, in the recording state, the light amount is modulated by the recording signal which is modulated so as to be suitable for recording on the disc 31, and becomes constant light in the reproducing state, and becomes constant in the stopped state. Try to be zero. Therefore, when the laser diode LD generates laser light under the control of the light stabilizer 33, the generated laser light is diffracted by the diffractor G.
After passing through the R diffraction grating, it becomes three beams, and an auxiliary beam for detecting a tracking signal is produced by the three-beam method via the beam splitter BS.

Then, the three beams including the main beam and the auxiliary beam projected through the beam splitter BS are focused on the signal track of the optical disc 31 through the objective lens OL, and then reflected again to be reflected by the sensor lens SL. And the photodetector PD '.

That is, of the three beams focused on the objective lens OL, the central main beam LB for reading an information signal as shown in FIG. 10B is a signal to be tracked as shown in FIG. 10A. Auxiliary beam LBr for detecting the tracking control signal so that it can be placed at the center of the track,
The LB1 is placed on the track of the optical disc 31 by being arranged at a point 0.25 times the land (groove) period Lp from the signal track to be traced left and right.

The optical disc 3 on which the information signal is recorded
The light reflected from the signal recording surface of No. 1 is condensed by the objective lens OL, passes through the beam splitter BS and is condensed by the sensor lens SL, and the photodetector PD as shown in FIG. 'Detect and read the signal.

At this time, as shown in FIG. 10A, in the optical disc having the structure of the land and the groove, the signal tracks for recording the information signals are placed at the centers of the signal tracks of the land and the groove, respectively, and the distance between the signal tracks, That is, if the track pitch is Tp, and the land period and the groove period are the same and Lp, the tracking control signal detection auxiliary beams are 0.
Arrange them so that they are 25 Lp apart. Therefore, the respective photodetecting elements (PDA, PDB, PD
C, PDD, PDE, PDF) are a, b,
The reproduction signal processing unit 3 generates electric signals corresponding to c, d, e, and f.
4 to obtain the focus control signal Fe, the tracking control signal Te, and the high frequency reproduction signal RF.

That is, the reproduction signal processing section 34 receives the input of the electric signals (a, b, c, d) detected from the photodetecting elements (PDA, PDB, PDC, PDD) (a + c)-.
(B + d) to detect the focus control signal Fe,
+ B + c + d) processing to detect the high frequency reproduction signal RF,
The electric signals e and f detected from the photodetection elements (PDE, PDF) are received (ef) and processed to detect the tracking control signal Te.

At this time, the focus control signal Fe output from the reproduction signal processing unit 34 is
The objective lens O for driving and focusing the focus driver FA of the optical pickup 32 after being input to the signal processing unit 5 and undergoing signal processing
The focus driver FA of the optical pickup 32 that drives L up and down, that is, in the focus axis direction, optimally collects light while keeping the distance between the objective lens OL and the optical disk 31 constant based on the focus control signal Fe. Then, the RF reproduction signal output from the reproduction signal processing unit 34 obtains information recorded by digital signal processing.

On the other hand, when recording or reproducing information on the signal track of the groove narrower than the land, that is, when tracking the signal track of the groove, the switching unit SW1 controls the reproduction signal processing unit 34 by the control of the microcomputer MC. It is connected to the control signal output terminal Te. Therefore, the tracking control signal Te output from the reproduction signal processing unit 34 is input to the tracking control unit 37. The tracking controller 37 processes the tracking control signal Te to drive the tracking driver TA of the optical pickup 32. The objective lens OL is the optical disc 3
The tracking driver TA that drives in the radial direction of 1 drives the objective lens OL based on the tracking control signal Te output from the tracking control unit 37 to generate a light beam for recording or reproducing at the center of the signal track of the land. Allow it to be posted.

On the other hand, when recording or reproducing on the signal track of the land wider than the groove, that is, when tracing the signal track of the land, the tracking control signal Te output from the reproduction signal processing section 34 is supplied to the inverting amplification section 36.
Invert by -1. Here, since the tracking control signal detected by the three-beam method is symmetrical, the resistance R
1, the amplification gain is set to 1 so that the R2 value becomes R1 = R2.
In this case, the inverting amplification section 36-1 serves only to invert the output of the reproduction signal processing section 34.

That is, when tracking the land signal track, only the polarity of the tracking control signal Te output from the reproduction signal processing section 34 is changed. At this time, the switching unit SW1 is connected to the output end of the inverting amplification unit 36-1 under the control of the microcomputer MC, so that the tracking control signal Te ^* output with the polarity changed by the inverting amplification unit 36-1 is output to the switching unit. It is output to the tracking control unit 37 via SW1. The tracking controller 37 processes the tracking control signal Te ^* to drive the tracking driver TA of the optical pickup 32 so that a light beam to be recorded or reproduced can be placed at the center of the land signal track.

In the above-described first to third embodiments of the present invention, the case where the land width ratio is wider than the groove width ratio has been described as an example, but the groove width ratio is larger than that of the land. If it is wider than the width ratio, the land and the groove move in the opposite direction.

That is, when the groove width is made wider than the land width and the groove width ratio is made larger than 0.5,
This is the same as the case where the width of the land is widened with respect to the groove track, the polarity of the detection signal changes with respect to the signal track of the groove, and the tracking signal of the land track keeps the same polarity, and the signal detection gain is More than triple.

Fourth Embodiment FIG. 11 is a block diagram of a recordable and read-only optical disk recording / reproducing apparatus according to a fourth embodiment of the present invention. An optical disk 41 and an optical pickup 42 for recording and reproducing information on the optical disk 41. An optical stabilizer 43-1 for stabilizing the generation of the laser light of the optical pickup 42, and an electric signal (a, b,
(c + d) input, (a + c)-(b + d) to generate a focus control signal Fe, and a focus control signal generator 44, and an electric signal a, b, c, d output from the optical pickup 42. In response to the input, the tracking control signal Tep, by the push-pull detection method and the phase difference detection method,
After detecting Ted respectively, the tracking control signals Tep and Ted are tracked along the land and groove tracks.
Tracking control signal output circuit 45 for directly or inverting and amplifying and outputting electric signals (a, b, c, d) output from the optical pickup 42.
An RF reproduction signal generator 46 that generates a high frequency reproduction signal RF by + c + d, and the focus control signal generator 44.
The focus control unit 47 that controls the focus of the optical pickup 42 using the focus control signal Fe output from the optical pickup 42 and the tracking control signal that is output from the tracking control signal output circuit 45 controls the tracking of the optical pickup 42. Tracking control unit 48
And a microcomputer (not shown) that outputs a control signal to the light stabilizer 43-1 and the tracking control signal output circuit 45. Here, the optical disc 41 is a CD
Or a high-density read-only disc such as a DVD, or a disc having a land and groove structure, and the land and groove of the optical disc having the land and groove structure have signal tracks respectively. Alternatively, the groove width ratio is set to a predetermined ratio.

At this time, the optical pickup 42 outputs a laser diode LD for generating a laser beam, a beam splitter BS for separating the input light and the reflected light, and a beam projected from the beam splitter BS onto a signal track of the optical disc 41. The objective lens OL for converging the light on the optical disc 41, the tracking driver TA and the focus driver FA for driving tracking and focus so that the objective lens OL can condense the beam on the signal track of the optical disc 41, and the astigmatism method. A sensor lens SL for obtaining a focus control signal, and a focus control signal generation unit 44, a tracking control signal output circuit 45, and an RF reproduction signal generation unit 4 by detecting light reflected from the optical disc 41 and entering.
6 and a photodetector PD for outputting to 6.

Here, as shown in FIG. 4, the photodetector PD for detecting the light quantity of the beam has a specific division in the signal track direction and the radial direction of the optical disc 41, that is, four divisions.
It is composed of individual photodetector elements PDA, PDB, PDC, PDD.

The tracking control signal output circuit 45 receives the electric signals a, b, c, d output from the photodetector PD of the optical pickup 42 (a +
d)-(b + c) to detect the tracking control signal Tep by the push-pull method, and the input of the electrical signals a, b, c, d output from the optical pickup 42. Receiving a + c to remove direct current, and b + d to remove direct current, and then comparing the phase difference between two signals to detect the tracking control signal Ted; Recording / reproducing disc controlled by the first tracking control signal tep detected by the push-pull method by amplifying the difference between the output of the 1-tracking control signal generator 45-1 and the output of the 2nd tracking-control signal generator 45-2 The first amplifier AMP1 for compensating the sensitivity of the track and the track when the information signal is recorded or reproduced on the signal track of the land wider than the groove. An inverting amplification section 45-3 which includes resistors R1 and R2 and a differential amplifier AMP2 for inverting and amplifying the ringing control signal Tep-, and a land signal track or a groove signal track in the case of a read-only disc or a recordable / reproducible disc. Switched according to tracking,
It is composed of a tracking control signal of the second tracking control signal generation unit 45-2, a tracking control signal of the first amplifier AMP1, and a switching unit SW1 for selectively outputting the tracking control signal of the inverting amplification unit 45-3.

At this time, the control signal R / G / L for switching the switching SW1 and the light stabilizer 43-
Control signal output to 1 (R / W / off, recording signal)
Is output from a microcomputer (not shown).

Then, the second tracking control signal generator 45-2 includes the photodetector P of the optical pickup 42.
A first summing amplifier 15-1 that sums and amplifies the a and c signals output from D, a first capacitor C1 that removes the DC component of the a + d signal output from the first summing amplifier 15-1, and the light The second summing amplifier 15 that sums and amplifies the b and d signals output from the photodetector PD of the pickup 42.
-2 and b + c output from the second summing amplifier 15-2
A second capacitor C2 that removes the DC component of the signal and a phase comparator that detects the tracking control signal Ted by comparing the phase difference between the two signals from which the DC components have been removed by the first and second capacitors C1 and C2. 15-3. Further, the focus control signal generator 44 and the RF reproduction signal generator 46 can be configured using a summing amplifier.

In the fourth embodiment of the present invention thus constructed, when the width ratio of the land to the groove is made larger than the width of the groove, the push-pull signal in the land signal track as shown in FIG. The tracking signal becomes a land cycle in which the sensitivity decreases and the sensitivity increases in the groove signal track.
As shown in, the control signal becomes the pitch cycle of the signal track. Therefore, if two signals are added with a polarity that improves sensitivity to the land track signal, which has deteriorated sensitivity, the signal will be reversed for the groove signal. In addition, the sensitivity is reduced and becomes more uniform.

That is, the light stabilizing unit 43-1 has the R / W / of
The light quantity of the laser diode LD is removed by the f signal and the recording signal. In the recording state, the light quantity is modulated by the recording signal which is modulated so as to be suitable for recording on the disc 41, and when reproducing, it becomes constant light. In the stopped state, the light quantity is set to zero.

At this time, the laser light emitted from the laser diode LD under the control of the light stabilizer 43-1 is reflected from the beam splitter BS and is reflected by the objective lens OL.
And the condensed light beam is placed on the signal track of the optical disc 41. The light reflected from the signal recording surface of the disc 41 on which the information signal is recorded is condensed again on the objective lens OL, passes through the beam splitter BS, and is condensed by the sensor lens SL, as shown in FIG. Such light enters the photodetector PD.

The photodetector PD outputs the electric signals a, b, c and d, which are proportional to the amount of light obtained from the respective photodetector elements, to the focus control signal generator 44, the tracking control signal output circuit 45 and the RF reproduction signal. Output to the generation unit 46.

The focus control signal generator 44 receives the electric signals a, b, c, d output from the photodetector PD of the optical pickup 42 and receives the electric signal (a
+ C)-(b + d) to generate the focus control signal Fe, and the focus control unit 47 outputs the focus control signal Fe.
Signal is processed to drive the focus driver FA of the optical pickup 42 to control the focus. In other words, the focus driver FA of the optical pickup 42 that drives the focusing objective lens OL up and down, that is, in the focus axis direction is optimal by keeping the distance between the objective lens OL and the optical disc 41 constant based on the focus control signal Fe. Focus on.

The RF reproduction signal generator 46 receives the electric signals a, b, c and d output from the photodetector PD of the optical pickup 42 and receives an a + signal from the summing amplifier.
The high frequency reproduction signal RF is generated by b + c + d, and the generated high frequency reproduction signal RF can obtain the recorded information by digital signal processing.

On the other hand, the first tracking control signal generating section 45-1 of the tracking control signal output circuit 45 adds the electric signals a, b, c and d output from the photodetector PD of the optical pickup 42 to an adding amplifier. By (a + d)
The tracking control signal Tep is generated by the push-pull method by-(b + c).

Then, the second tracking control signal generator 45-2 a + c the electric signals a, b, c, d output from the photodetector PD of the optical pickup 42 by the first summing amplifier 15-1. After that, the DC component is removed via the first first capacitor C1, b + d is performed by the second summing amplifier 15-2, and the direct current component is removed via the second capacitor C2, and then output to the phase comparator 15-3. The phase comparator 15-3 compares the phase difference between the two signals from which the DC component has been removed, and generates the tracking control signal Tep of the phase difference detecting method. At this time, when the reproduction-only disc is reproduced, the switching unit SW1 is connected to the second tracking control signal generation unit 45-2 by the R / G / L signal, so that the tracking control signal Ted detected by the phase difference detection method is generated. The tracking driver TA of the optical pickup 42 is driven via the tracking controller 48.

The tracking driver TA for driving the objective lens OL in the radial direction of the optical disc 41 drives the objective lens OL based on the tracking control signal Ted to place the light beam on the center of the signal track on the disc 41. To do so.

On the other hand, when recording or reproducing the recordable / reproducible disc, the control is performed by the tracking control signal Tep detected by the push-pull method. However, since the sensitivity of the control signal differs depending on whether or not the signal is recorded,
In order to compensate with the signal of the phase difference detection method detected by the signal pit, the first amplifier AMP1 performs Tep-Ted and outputs the Tep- signal. This is a signal close to the tracking control signal of FIG.

At this time, when recording or reproducing a signal track of a groove narrower than the land width ratio, R / G
/ L signal causes the switching unit SW1 to output the first amplifier A
It is connected to the output terminal of MP1 and, as a result, the first amplifier AM
The tracking control signal Tep− output from P1 drives the tracking driver TA of the optical pickup 42 via the tracking controller 48. That is, the objective lens O
The tracking driver TA that drives L in the radial direction of the optical disc 41 drives the objective lens OL based on the tracking control signal Te so that the optical beam to be recorded or reproduced is placed at the center of the signal track of the groove on the disc 41. To be able to

On the other hand, when recording or reproducing on a signal track of a land wider than the groove, the sensitivity of the reproduced signal is lowered and the polarity must be changed.
Inversion amplification unit 45 including R2 and differential amplifier AMP2
The output Tep− of the first amplifier AMP1 is inverted and amplified via 3. At this time, the resistance value is set to R2 / R1> 3. Then, the switching unit SW1 is connected to the output end of the inverting amplification unit 45-3 by the R / G / L signal, so that the tracking control signal T of the inverting amplification unit 45-3 is obtained.
ep- ^* is output to the tracking control unit 48, and the tracking control unit 48 performs the signal processing of the tracking control signal Tep- ^* to drive the tracking driver TA of the optical pickup 42 and record it at the center of the land signal track. Alternatively, the light beam to be reproduced is placed.

On the other hand, in the case of an empty disc on which no signal is recorded, there is no output of the second tracking control signal generator 45-2 for detecting the tracking control signal by the phase difference detection method, and therefore the output of the first amplifier AMP1. Is the output of the first tracking control signal generator 45-1 that detects the tracking control signal by the push-pull method, and the output of the first amplifier AMP1 is directly or inverted amplified in accordance with the tracking of the groove signal track or the land signal track. Part 4
It is output to the tracking control unit 48 via 5-3.

In the above-described fourth embodiment of the present invention, the case where the land width ratio is wider than the groove width ratio has been described as an example, but conversely, the groove width ratio is wider than the land width ratio. In this case, the land and groove tracks change, but the land and groove operations are reversed.

That is, when the width of the groove is made wider than the width of the land and the ratio of the width of the groove is made larger than 0.5, it is the same as the case where the width of the land is widened with respect to the track of the groove. The polarity of the detection signal changes with respect to the signal track, the tracking signal of the land track keeps the same polarity, and the signal detection gain increases three times or more.

[0112]

As described above, it is possible to reproduce a read-only optical disc with a recording / reproducing apparatus for recording / reproducing a recordable disc having a land and groove structure.
Further, it is possible to perform stable tracking control even when recording or reproducing on a recordable disc that tracks with a land (groove) cycle with different land and groove ratios. On the other hand, the phase difference detection method can be replaced with any method of detecting the tracking control signal from the high frequency signal corresponding to the signal pit of the recorded information signal.

Since there is no division between the land and groove tracks for a recordable disc having the same land and groove width, tracking control is performed by the tracking control signal Tep- output from the first amplifier AMP1. be able to.

As described above, according to the optical disc and the optical disc recording / reproducing apparatus of the present invention, the land and groove width ratios of the optical disc for recording information on the land and groove signal tracks are different from each other. By making it possible to obtain the tracking control signal of the cycle, the minimum distance to jump over the track in the cycle of the land or groove can be doubled to reduce the track crossing due to disturbance such as external impact or electric noise. It is easy to change tracking of land and groove tracks on an optical disc that controls tracking stably and records information signals on land and groove tracks respectively.

When recording / re-recording / reproducing a recordable disc having a structure of lands and grooves, it is possible to increase the sensitivity difference due to the signal recorded as the tracking control signal detected by the push-pull method. Tracking is controlled by compensating with the tracking control signal detected by the phase difference detection method, tracking is controlled by the phase difference detection method when playing a read-only disc, and push-pull when recording on an empty disc. By controlling tracking by the method, it is possible to perform stable tracking control and to record / reproduce an optical disk having a signal track for recording an information signal on each of the land and the groove, which has a structure of the land and the groove. Play-only disc playback, blank disc recording, recordable disc recording And it is possible to perform all reproduction.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an optical disc having a general land and groove structure.

FIG. 2 is a waveform diagram of a tracking control signal in an optical disc having the same land and groove widths as in FIG.

FIG. 3 is a block diagram of a general compact disc and a high-density playback-only disc playback device.

FIG. 4 is a configuration diagram of the photodetector of FIG.

5 is a waveform diagram of a tracking control signal detected by the phase difference detection method in FIG.

FIG. 6 is a signal waveform diagram showing a change in a tracking control signal due to a change in a land / groove width ratio of the present invention.

FIG. 7 is a waveform diagram of a tracking control signal in an optical disc on which an information signal according to the present invention is recorded.

FIG. 8 is a block diagram of a one-beam type optical disc recording / reproducing apparatus according to the present invention.

FIG. 9 is a block diagram of a three-beam type optical disc recording / reproducing apparatus according to the present invention.

10A is a light beam array diagram on the optical disc of the three-beam system of FIG. 9, and FIG. 10B is a configuration diagram of a photodetector of the three-beam system of FIG.

FIG. 11 is a block diagram of a recordable and read-only optical disc recording / reproducing apparatus according to the present invention.

12 is a waveform diagram of a tracking control signal detected by the push-pull method of FIG.

[Explanation of symbols]

 21, 31, 41 Optical disc 22, 32, 42 Optical pickup 23, 33, 43-1 Optical stabilizer 24, 34, 44 Reproduction signal processor 25, 35, 47 Focus controller 26, 36 Tracking control signal output unit 27, 37, 48 tracking control unit 45 tracking control signal output circuit 46 RF reproduction signal generation unit MC microcomputer

Claims (23)

[Claims] 1. In an optical disc having a land and groove structure and having signal tracks for recording information signals in the land and the groove, the width ratio of the land and the groove is set differently, The optical disc is characterized in that the tracking control signal of the land or groove cycle can be detected by recording the information on the land and groove signal tracks whose ratios are set differently. 2. The optical disk is a magneto-optical disk whose reflectance does not change, and the width ratio of lands or grooves is 0.6 or more and 0.8 or less. The described optical disc. 3. The optical disc is a disc on which an information signal is recorded by a change in reflectance, and the width ratio of lands or grooves is 0.635 or more and 0.8 or less. The optical disc according to item 1. 4. An apparatus for recording / reproducing an optical disc having a structure of lands and grooves, and having signal tracks for recording information signals on the lands and grooves respectively, wherein the ratio of the width of the lands to the grooves is set to a predetermined ratio. An optical disc, an optical pickup that records and reproduces information on the optical disc, and a reproduction signal processing unit that receives a focus control signal, a tracking control signal, and a high-frequency reproduction signal by receiving an electric signal output from the optical pickup, Focus control means for controlling the focus of the optical pickup using the focus control signal output from the reproduction signal processing means, and output from the reproduction signal processing means in response to tracking of a land signal track or a groove signal track. Tracking control signal is output directly or inverted. Optical disc recording and reproducing apparatus for the tracking control signal output means, characterized in that it comprises a tracking control means for controlling the tracking of an optical pickup using a tracking control signal output from the tracking control signal output means for. 5. The tracking control signal output means comprises a plurality of resistors and a differential amplifier connected in series and parallel,
The inverting amplifier for inverting and amplifying the tracking control signal output from the reproduction signal processing means to a predetermined gain, an empty disc, and the inverting amplifier for compensating for a difference in sensitivity of detection signals in a disc on which a signal is recorded. And a first switching unit for controlling the amplification gain of the unit, and the tracking control signal of the reproduction signal processing unit or the tracking control signal of the inverting amplification unit is switched according to the tracking of the land signal track or the groove signal track. The optical disc recording / reproducing apparatus according to claim 4, wherein the optical disc recording / reproducing apparatus comprises a second switching unit which selectively outputs the control unit. 6. The optical disc recording / reproducing apparatus according to claim 5, wherein the first switching unit controls an amplification gain of an optical disc for recording an information signal according to a change in reflectance. 7. The first switching unit controls the inverting amplification unit so that an amplification gain of a tracking control signal of a disc on which a signal is recorded is larger than that of an empty disc. Item 6. The optical disk recording / reproducing apparatus according to item 6. 8. The optical disk recording / reproducing apparatus according to claim 5, wherein the first switching unit fixes an amplification gain of a disk having no change in reflectance. 9. An apparatus for recording / reproducing an optical disc having a structure of lands and grooves and having signal tracks for recording information signals on the lands and grooves respectively, wherein the ratio of the widths of the lands and the grooves is set to a predetermined ratio. An optical disc, an optical pickup that generates a main beam for reading a signal and an auxiliary beam for tracking detection, and records and reproduces information on the optical disc, and is output from the optical pickup in proportion to the light amount of the main beam. Reproduction signal processing means for receiving a focus control signal and a high frequency reproduction signal in response to an electric signal input from the optical pickup, and for detecting a tracking control signal in response to an electric signal output from the optical pickup in proportion to the light quantity of the auxiliary beam. And an optical pickup using a focus control signal output from the reproduction signal processing means. Focus control means for controlling the focus, and tracking control signal output means for outputting the tracking control signal output from the reproduction signal processing means directly or by inversion according to the tracking of the land signal track or the groove signal track, An optical disk recording / reproducing apparatus, comprising: a tracking control means for controlling tracking of an optical pickup using a tracking control signal output from the tracking control signal output means. 10. The tracking control signal output means is composed of a plurality of resistors having an amplification gain of 1 and a differential amplifier, and an inverting amplification section for inverting the tracking control signal output from the reproduction signal processing means, and a land. And a switching unit for switching the tracking control signal of the reproduction signal processing unit or the tracking control signal of the inverting amplification unit to the tracking control unit. The optical disk recording / reproducing apparatus according to claim 9, wherein 11. A main beam for reading an information signal from the optical pickup is disposed at the center of a signal track to be tracked, and an auxiliary beam for detecting a tracking control signal is left and right, respectively, a period of a land from the signal track to be tracked. 10. The optical disk recording / reproducing apparatus according to claim 9, wherein the optical disk recording / reproducing apparatus is arranged at a position of 0.25 of the above so as to be placed on the track of the optical disk. 12. A disc having a land / groove width ratio set differently, and information can be inserted into a land / groove signal track having the width ratio set, wherein the land or groove is reproduced at the time of signal reproduction of the disc. An optical disk recording / reproducing apparatus, characterized in that the tracking control signal is detected to perform tracking control. 13. A disc in which the land and groove ratios are set differently and information is masked in the land and groove signal tracks in which the width ratio is set, and an optical pickup for reading the masked information in the disc. A reproduction signal processing means for receiving the input of an information signal output from the optical pickup and detecting a tracking control signal; and a tracking control signal output from the reproduction signal processing means for tracking control of a land or groove width cycle. An optical disk recording / reproducing apparatus comprising: a tracking control signal output means for outputting as a signal, and a tracking control means for performing tracking based on a tracking control signal output from the tracking control signal output means. 14. An optical pickup that records and reproduces information on an optical disc by a laser beam, and first and second optical pickups that receive an electric signal output from the optical pickup and detect tracking errors by different detection methods. A tracking error detection unit and an optical signal from the optical pickup are input to determine the type of the optical disc, and tracking is performed by the detection output of the first tracking error detection unit or the detection output of the second tracking error detection unit according to the determination result. An optical disk recording / reproducing apparatus comprising: a control unit for controlling the operation. 15. The optical disc recording / reproducing apparatus according to claim 14, wherein the first tracking error detecting means detects a tracking error by a phase difference detecting method. 16. The optical disk recording / reproducing apparatus according to claim 14, wherein the second tracking error detecting means detects a tracking error by a push-pull detection method. 17. An optical pickup that records and reproduces information on an optical disc by a laser beam, tracking control signal output means that receives a tracking control signal by a different detection method using an electric signal of the optical pickup as an input, and the optical pickup. A control unit that determines the type of the optical disc by using an electric signal of a pickup as an input and outputs a control signal based on the determination result; and a tracking control signal that is selectively output from the tracking control signal output unit according to the control of the control unit. An optical disk recording / reproducing apparatus comprising: a tracking control means for performing tracking by the optical disc. 18. The optical disc recording / reproducing apparatus according to claim 17, wherein the tracking control signal output means detects the tracking control signal by a phase difference detection method and a push-pull detection method. 19. The tracking control means controls tracking by a tracking control signal detected by a phase difference detection method when reproducing a read-only disc. Optical disc recording / reproducing apparatus. 20. The tracking control means controls tracking by a tracking control signal detected by a push-pull detection method when recording on an empty disc. Optical disc recording / reproducing apparatus. 21. When the recorded disc is reproduced or re-recorded, the tracking control means detects that a recorded signal of the tracking control signals detected by the push-pull method causes a further increase in sensitivity difference. 19. The optical disc recording / reproducing apparatus according to claim 17, wherein tracking is controlled by compensating with a tracking control signal detected by a phase difference detection method. 22. The tracking control signal output means is an electrical signal (a, b,) output from the optical pickup.
c, d) is (a + d)-(b + c) to detect the tracking control signal by the push-pull method, and the electric signal (a, b,
c, d) a + c to remove direct current, and b + d to remove direct current, and then a second tracking control signal generator for comparing a phase difference between two signals to detect a tracking control signal; Recording / reproduction is possible in which the difference between the output of the tracking control signal generator and the output of the second tracking control signal generator is amplified and controlled by the tracking control signal detected by the push-pull method from the first tracking control signal generator. An amplifier for compensating the sensitivity of the optical disk, and a tracking control output from the amplifier for reversing the polarities of the tracking control signals when tracking the land signal track and the groove signal track. An inverting amplifier section that inverts and amplifies the signal, and in the case of a read-only disc or a recordable and reproducible disc, the land signal track or group. And a switching unit for selectively outputting the tracking control signal of the second tracking control signal generating unit, the tracking control signal of the amplifying unit, and the tracking control signal of the inverting amplifying unit. 18. The optical disc recording / reproducing apparatus according to claim 17, wherein: 23. The second tracking control signal generator includes a first summing amplifier that sums and amplifies the a and c signals output from the optical pickup, and a DC component of the a + c signal output from the first summing amplifier. A second capacitor for removing and amplifying the b and d signals output from the optical pickup; and a second capacitor for removing the DC component of the b + d signal output from the second adding amplifier. 23. The optical disk recording / reproducing apparatus according to claim 22, further comprising: a phase comparator that detects a tracking control signal by comparing the phase difference between the two signals from which the DC components have been removed by the first and second capacitors.