JPH0773492A - Optical disk device - Google Patents

Abstract

(57) [Abstract] [Purpose] Even during seek operation, the beam spot always has an area where the information track width is 1/2 or less of the track pitch and an area where the information track width is 1/2 or more of the track pitch. There is provided an optical disk device capable of discriminating which one of the two. [Structure] An optical disk device equipped with an optical disk 5 having an area 5a in which the width of an information track is 1/2 or less of a track pitch and an area 5b of 1/2 or more of the track pitch, and the phase of a push-pull tracking error signal and the amount of total reflection light. Signal phase of the signal,
The signal indicating the moving direction of the beam spot is multiplied by the multiplier 12 to obtain a phase discrimination signal. Since the beam spot is in the region 5a and in the region 5b, the polarity of the push-pull tracking error signal does not change, and the polarity of the multiplication result of the differential signal of the total reflected light amount and the signal indicating the beam spot moving direction is Invert. By determining the polarity of the multiplication signal, it is determined whether the beam spot is in the area 5a or the area 5b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk device, and particularly to an area 1 in which the width of an information track is 1/2 or less of a track pitch and an area 2 in which the width of an information track is 1/2 or more of a track pitch. The present invention relates to an optical disk device provided with an optical disk having

[0002]

2. Description of the Related Art In recent years, video discs, audio discs, and data files are being commercialized as information recording / reproducing devices using optical discs. Recently, one disc has both a reproduction-only area and a recordable area. So-called hybrid discs are in the stage of practical application. FIG. 15 shows an example of a hybrid disc. Figure 15
2A is a diagram showing the configuration of a hybrid disc, FIG. 4B is an enlarged view showing the configuration of information tracks in a read-only area, and FIG. 3C is an enlarged view showing the configuration of information tracks in a recordable area. In FIG. 15, 5 is a hybrid disc, 5a is a read-only region on the inner periphery of the hybrid disc 5, 5b is a recordable region on the outer periphery of the hybrid disc 5, 201 is a protective material, and 202 is a protective material of the read-only region 5a. A recording material attached to 201, 203 a convex recording pit formed on the recording material 202, 204 a recording material attached to the protective material 201 of the recordable area 5b,
205 is a convex guide groove groove formed on the recording material 204, 206 is an information recording mark, 207 is a track pitch, 208 is an information track center line, and 209 is a guide groove 2.
It is a concave land between 05. In the read-only area 5a, the width of the read-only information is 1 of the track pitch 207.
It is recorded by pits 203 of / 2 or less. In the read-only area, the read-only information is recorded by including the disc position information. In the recordable area 5b, the information recording mark 206 is recorded by applying a light beam spot to the groove 205 whose width is 1/2 or more of the track pitch 207. In the recordable area, the groove 205 is formed to meander, and the position information of the disc is recorded by the displacement of the shape of the groove 205 in the radial direction. Therefore, the position information is superimposed on the tracking error signal and detected. With this position information, it is possible to selectively record the record information in the target area of the recordable area 5b.

A conventional optical disk device will be described below. FIG. 16 is a block diagram of an optical disc device according to the conventional technique.

The configuration will be described. In FIG. 16, 5
Is a hybrid disc and has the same configuration as that described with reference to FIG. 11, and therefore, the same reference numerals are given and detailed description is omitted. The hybrid disc 5 is attached to the rotary shaft of the disc motor 22. 1 is a laser diode. Reference numeral 2 denotes a collimator lens fixed on the optical path of the laser diode. Reference numeral 3 is a beam splitter fixed on the optical paths of the laser diode and the collimator lens 2. Reference numeral 4 denotes an objective lens mounted on the optical paths of the laser diode 1, the collimator lens 2, and the beam splitter 3 so as to be movable in the radial direction of the hybrid disc 5 together with a tracking actuator described later. Reference numeral 6 denotes a lens in which the light reflected by the hybrid disc 5 is further fixed on the optical path of the light reflected by the beam splitter 3. Reference numeral 7 is a photodetector fixed to the focal point of the lens 6. The photodetector 7 outputs a signal to a third switch described later. The photodetector 7 is divided into two in the radial direction of the hybrid disk 5, 7a being a photodetector on the inner peripheral side, and 7b being a photodetector on the outer peripheral side. Reference numeral 8 is a differential amplifier in which the output of the photodetector 7a is input to the non-inverting input and the output of the photodetector 7b is input to the inverting input. Reference numeral 13 is a first switch to which the output of the differential amplifier 8, the zero potential and the output of the command device described later are input. 14
Is a first control circuit to which the output of the first switch 13 is input. Reference numeral 15 is a tracking actuator to which the output of the first control circuit is input and which is attached to the hybrid disc 5 together with the objective lens 4 so as to be movable in the radial direction. Reference numeral 16 is a second switch to which the output of the differential amplifier 8 and the two outputs of the command device to be operated later are input. Reference numeral 17 is a second control circuit to which the output of the second switch 16 is input. Reference numeral 18 is a seek motor to which the output of the second control circuit 17 is input. Reference numeral 19 is a seek gear which is attached to the rotary shaft of the seek motor 18 and which meshes with a tooth portion described later. In FIG. 16, the seek gear 19 is shown in a sectional view. Reference numeral 20 is provided with a laser diode 1, an optical element 2, a beam splitter 3, an objective lens 4, a tracking actuator 15, a lens 6 and a photodetector 7, and a tooth portion described later is provided on a seek gear 19 so as to be movable in the radial direction of the optical disk 23. It is an optical pickup that meshes. Two
4 is an input of the output of a signal processing circuit described later, and
To output a first control signal to the switch 13 and the second switch 16 and to output a second control signal to the second switch 16, and to a third switch and a signal processing circuit which will be described later. It is a command device that outputs a control signal. Reference numeral 25 is a third switch to which the output signal of the photodetector 7, the output of the differential amplifier 8 and the third control signal of the command device 24 are input. Reference numeral 26 is a signal processing circuit that receives the output of the third switch and the third control signal output from the command device 24 and outputs a signal to the command device 24. 40 is an optical pickup 2
The tooth portion is fixed to 0, meshes with the seek gear 19, and is attached so as to be movable in the radial direction of the hybrid disc 5. The tooth portion 40 is shown in a sectional view in FIG.

The operation of the conventional optical disk device configured as described above will be described. The laser light output from the laser diode 1 passes through the collimator lens 2 and becomes parallel light. Further, the light passes through the beam splitter 3, is condensed by the objective lens 4, and reaches the hybrid disc 5. Although detailed description is omitted because it is not directly related to the object of the present invention, the objective lens 4 is normally mounted movably in the optical axis direction, and focusing control is performed. Hybrid disc 5
The light beam reflected by is incident on the lens 6 through the objective lens 4 and the beam splitter 3. The light beam is condensed by the lens 6 and is incident on the photodetector 7, and an electric signal is output from the photodetector 7. The differential amplifier 8 outputs a push-pull tracking error signal.

First, the case of recording and reproducing will be described. The command device 24 switches the first switch 13 by the first control signal and outputs a push-pull tracking error signal to the first control circuit 14. First control circuit 14
Applies a drive signal according to the push-pull tracking error signal to the actuator 15 to move the objective lens 4 and follow the information track. Further, the command device 24 switches the second switch 16 according to the first control signal, and applies the push-pull tracking error signal to the second control circuit 17. The second control circuit 17 applies a drive signal corresponding to the low frequency component of the push-pull tracking error signal to the motor 18 to move the optical pickup 20 and follow the information track. First, when reproducing the reproduction-only area 5a, the command device 24 switches the third switch 25 by the third control signal and outputs the reproduction information signal output from the photodetector 7 to the signal processing circuit 26. The signal processing circuit 26 is the command device 24.
When it is determined that the area is the reproduction-only area based on the third control signal output from, the position information of the disk is detected from the reproduction information signal and output to the command device 24. On the other hand, when recording / reproducing the recordable area 5b, the command device 24 switches the third switch 25 by the third control signal and outputs the push-pull tracking error signal output from the differential amplifier 8 to the signal processing circuit 26. . When the signal processing circuit 26 determines from the third control signal output from the command device 24 that the recording area is possible, the signal processing circuit 26 detects the position information of the disc from the push-pull tracking error signal and outputs the command device 24.
Output to.

On the other hand, when the seek operation is performed, the command device 2
Reference numeral 4 switches the first switch 13 by the first control signal, and applies 0 potential to the first control circuit 14. The first control circuit 14 sends a drive signal corresponding to the 0 potential to the actuator 1
In addition to 5, the objective lens 4 is kept at a constant relative position with respect to the optical pickup 20. Further, the command device 24 switches the second switch 16 by the first control signal, and outputs the second control signal corresponding to moving the optical pickup 20 to the target position to the second control circuit 17. The control circuit 17 applies a drive signal to the motor 18 and the optical pickup 20.
In the radial direction of the disc.

By the way, as described with reference to FIG. 15, the position information of the disc is included in the reproduction information when the optical pickup 20 is in the read-only area 5a, and the position information of the disc is included in the recordable area 5b. It is superimposed on the push-pull tracking error.

Therefore, after the seek operation is completed and the tracking control is applied, it is determined whether the area where the beam spot is currently located is the reproduction-only area or the recordable area by using the reproduction information signal or the push-pull tracking error signal described above. Is judging.

[0010]

However, since the position information cannot be read when tracking control is not applied, such as during seek operation or track jump operation, the area where the beam spot is currently located is for reproduction only. In order to determine whether it is the area or the recordable area, it is necessary to perform tracking control and determine the area using the reproduction information signal or the push-pull tracking error signal. Therefore, there is a problem that the position information cannot be obtained immediately after the movement.

The present invention is to solve the above-mentioned conventional problems. Even during a seek operation, the optical pickup always has a read-only area in which the width of the information track is 1/2 or less of the track pitch and the information track. Width is 1 / track pitch
It is an object of the present invention to provide an optical disk device capable of immediately obtaining position information of a target position after being moved, since it can be discriminated which one of two or more recordable areas.

[0012]

In order to achieve the above object, the optical disk device of the present invention has an area 1 in which the width of the information track is less than 1/2 of the track pitch and the width of the information track is 1 / of the track pitch. An optical disk device having an optical disk having two or more areas 2, comprising a push-pull tracking error detection means, a total reflection light amount detection means,
Phase comparison means for comparing the phase of the push-pull tracking error signal output from the push-pull tracking error detection means with the phase of the total reflection light quantity signal output from the total reflection light quantity detection means according to the beam spot moving direction is provided. It has a configuration provided.

[0013]

With the above configuration, the phase of the push-pull tracking error signal and the phase of the total reflected light amount signal are phase-compared according to the beam spot moving direction, and the phase comparison result is obtained. Based on this detection signal, whether the beam spot is in the area 1 or the area 2 is determined by the position after the movement of the beam spot.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an optical disk device according to the first embodiment of the present invention. The configuration of the optical disk device of this embodiment will be described below with reference to FIG. In FIG. 1, 1 is a laser diode, 2 is a collimator lens, 3 is a beam splitter, 4 is an objective lens, 5 is a hybrid disc, 6 is a lens, 7 is a photodetector, 7a and 7b are photodetectors, and 8 is a difference. Motion amplifier, 13
Is a first switch, 14 is a first control circuit, 15 is a tracking actuator, 16 is a second switch, 17
Is a second control circuit, 18 is a seek motor, 19 is a seek gear, 20 is an optical pickup, 22 is a disk motor,
Reference numeral 25 is a third switch, 26 is a signal processing circuit, and 40 is a tooth portion. The above is basically the same as the constituent elements of the conventional example described with reference to FIGS. The same reference numerals are given and detailed description is omitted. Reference numeral 9 is an adder to which the output of the photodetector 7a and the output of the photodetector 7b are input. Reference numeral 10 is a differentiator to which the output of the adder 9 is input. Reference numeral 11 is a multiplier to which the output of the differential amplifier 8, the output of the differentiator 10, and the second control signal output from the command device described later are input. 12 is the output of the multiplier 11 and 0
It is a voltage comparator that receives a potential and outputs the output to a command device described later. 21 is an input of the output of the signal processing circuit 26, and the first switch 13 and the second switch 1
6 outputs the first control signal and outputs the second switch 16
And a second control signal to the multiplier 11, and a third control signal
Is a command device to which the third control signal is output to the switch 25 and the signal processing circuit 26 and the output of the voltage comparator 12 is input. 50 receives the output of the differential amplifier 8, the output of the adder 9, and the second control signal output by the command device 21,
It is a phase comparison means composed of a differentiator 10, a multiplier 11, and a voltage comparator 12.

The operation of the optical disk device configured as described above will be described below. The differential amplifier 8 generates a push-pull tracking error signal as in the conventional example, and outputs the push-pull tracking error signal to the first switch 13, the second switch 16, the third switch 25, and the multiplier 11. The output of the photodetector 7a is input to the adder 9, the output of the photodetector 7b is input to the adder 9, and the adder 9 outputs the total reflection light amount signal to the differentiator 10.

The relationship between the push-pull tracking error signal and the total reflection light amount signal will be described with reference to the drawings. 2, 3 and 4, 4 is an objective lens, 7
a and 7b are photodetectors divided into two in the radial direction of the hybrid disk 5, 7a is a photodetector on the inner peripheral side, and 7b.
Is a photodetector on the outer peripheral side, 5 is a hybrid disc,
Reference numeral 8 is a differential amplifier, and 9 is an adder. The above are the same components as those of the embodiment shown in FIG. Reference numeral 400 denotes a beam of reflected light from the hybrid disc 5. 701,702,703,704,7
Reference numerals 05, 706 and 707 are curves showing the intensity distribution of the reflected light reflected by the disk 5. Reference numeral 5a is a read-only area, 203 is a pit, 5b is a recordable area, 205 is a groove, 208 is a center line of an information track, and 209 is a land, which are the same as those described with reference to FIG. Is attached.

2 is a sectional view of the hybrid disc 5 in the radial direction. In FIG. 2, the configuration of the optical system is omitted for simplicity of explanation.

The main beam 400 reflected by the hybrid disc 5 has a far-field intensity distribution 701 and is incident on the photodetectors 7a and 7b. The outputs according to the intensity distribution 701 of the photodetectors 7a and 7b are input to the differential amplifier 8, and the differential amplifier 8 receives the photodetectors 7a.
Output of the photodetector 7b, that is, a push-pull tracking signal is output. Similarly, the outputs corresponding to the intensity distribution 701 of the photodetectors 7a and 7b are input to the adder 9, and the adder 9 outputs the output of the photodetector 7a and the photodetector 7b.
The sum of the outputs of b, that is, the total reflection light amount signal is output.

When the push-pull tracking error detection method and the total reflection light amount detection method as described above are used for the hybrid disc as described above, the polarities of the push-pull tracking error signal in the read-only area 5a and the recordable area 5b are the same. It is known that the polarity of the total reflection light amount signal is inverted without being inverted.

This will be described below. First, the case where the beam 400 is in the reproduction-only area will be described with reference to FIG. 3A, 3B, and 3C are diagrams showing the positions of the pit and the beam. FIG. 3D is a characteristic diagram of the push-pull tracking error signal with respect to the track deviation amount d. FIG. 3D shows the track deviation amount d.
FIG. 6 is a characteristic diagram of a total reflection light amount signal for.

FIG. 3B shows the center line 20 of the information track.
This is the case where the optical axis of the beam 400 is directly above 8. In this case, the effect of the pit on the reflected light is symmetrical,
There is no difference between the outputs of the photodetectors 7a and 7b, and the push-pull tracking error signal becomes 0 as shown at point B in FIG. 3D. Further, since the light intensity becomes smaller due to the influence of the pits 203 than in the portion without the pits 203, the outputs of the photodetectors 7a and 7b become low, and the total reflected light quantity signal is B in FIG. 3 (e). As shown by the point, it is the smallest in the reproduction-only area 5a.

FIG. 3A shows the case where the beam 400 is on the inner peripheral side of the hybrid disc 5 by a distance d which is ¼ of the track pitch 207 with respect to the center line of the information track. In this case, the reflected light is larger on the left side than on the right side with respect to the optical axis of the beam 400, the light intensity distribution is as shown by 702, and the output of the photodetector 7a is larger than the output of the photodetector 7b. The push-pull tracking error signal becomes a positive signal as shown at point A in FIG. Further, although the light intensity is lower than that of the portion without the pit 203 due to the influence of the pit 203, the amount of the pit 203 in the beam 400 is smaller than that of FIG. The total reflection light amount signal becomes larger than the point B as shown at the point A in FIG.

FIG. 3C shows the case where the beam 400 is on the outer peripheral side of the hybrid disc 5 by a distance d which is ¼ of the track pitch 207 with respect to the center line of the information track. In this case, the reflected light becomes larger on the right side than on the left side with respect to the optical axis of the beam 400, the light intensity distribution becomes like 704, and the output of the photodetector 7a becomes smaller than the output of the photodetector 7b. The push-pull tracking error signal becomes a negative signal as shown at point C in FIG. Further, the light intensity is lower due to the influence of the pits 203 than in the portion without the pits 203, but the amount of pits in the beam 400 is smaller than that in FIG. The reflected light amount signal becomes larger than that at point B, as shown at point C in FIG.

On the other hand, the case where the beam 400 is in the recordable area will be described with reference to FIG. 4 (a),
4B and 4C are diagrams showing the positions of the groove 205 and the beam 400, and FIG. 4D is a diagram showing the track deviation amount d.
It is a characteristic view of a push-pull tracking error signal.

FIG. 4B shows the center line 20 of the information track.
This is the case where the beam 400 is directly above 8. In this case, the influence of the groove 205 on the reflected light is bilaterally symmetric, there is no difference in the outputs of the photodetectors 7a and 7b, and the push-pull tracking error signal is B in FIG.
It becomes 0 as indicated by the point. Further, the influence of the groove 205 is larger than that in the case where the beam 400 is directly above the land 209, so that the outputs of the photodetectors 7a and 7b are large and the total reflection light amount signal is shown in FIG. It becomes the maximum in the recordable area 5b as indicated by point B in (e).

FIG. 4A shows the case where the beam 400 is on the inner peripheral side of the hybrid disc 5 by a distance d which is ¼ of the track pitch 207 with respect to the center line of the information track. In this case, in the reflected light, the left side with respect to the optical axis of the beam 400 is larger than the right side, the light intensity distribution is as shown by 705, and the output of the photodetector 7a is larger than the output of the photodetector 7b. The push-pull tracking error signal becomes a positive signal as indicated by point A in FIG. Further, although the light intensity is higher due to the influence of the land 209 than in the case where the beam 400 is directly above the land 209,
Since the amount of land 209 applied to the beam 400 is smaller than that in FIG. 4B, the light intensity is large, and the total reflection light amount signal is larger than that in B point as shown in A point in FIG. growing.

FIG. 4C shows the case where the beam 400 is on the outer peripheral side of the hybrid disc 5 by a distance d which is ¼ of the track pitch 207 with respect to the center line of the information track. In this case, the reflected light becomes larger on the right side with respect to the optical axis of the main beam 400 than on the left side, the light intensity distribution becomes like 707, and the output of the photodetector 7a becomes smaller than the output of the photodetector 7b. The push-pull tracking error signal becomes a negative signal as shown at point C in FIG. Further, although the light intensity is higher due to the influence of the land 209 than in the case where the beam 400 is directly above the land 209,
Since the amount of land 209 applied to the beam 400 is smaller than that in FIG. 4B, the light intensity is high, and the total reflection light amount signal is higher than that in B point as shown in C point in FIG. 4E. growing.

Therefore, the polarity of the push-pull tracking error signal does not change regardless of whether the optical pickup is in the read-only area 5a or the recordable area, and conversely, the polarity of the total reflection light amount signal is inverted. Moreover, the phase difference between the push-pull tracking signal and the total reflection light amount signal is ± 9.
It is 0 degree and depends on the track shift amount. That is, the phase difference is reversed as shown in (Table 1) when the beam 400 moves from the inner circumference to the outer circumference of the hybrid disc 5 and when the beam 400 moves from the outer circumference to the inner circumference.

[0030]

[Table 1]

Returning to FIG. 1, the description of the operation of the embodiment will be continued. The differentiator 10 differentiates the totally reflected light amount signal output from the adder 9 and outputs a differentiated totally reflected light amount signal having a phase of 90 degrees and having no DC component. The multiplier 11 multiplies the push-pull tracking error signal, the differential total reflection light amount signal, and the second control signal output from the command device 21, and outputs the multiplication result to the voltage comparator 12 as a multiplication signal. To do.

It will be described that the multiplication signal becomes a negative signal in the read-only area 5a and becomes a positive signal in the recordable area 5b.

First, in the case where the beam 400 exists in the reproduction-only area 5a, and the beam 400 goes from the inner circumference to the outer circumference.
The case of moving will be described with reference to FIG.

As described with reference to FIG. 3D, the push-pull tracking error signal is a positive signal when the beam spot is on the inner circumference side with respect to the center line 208 of the information track, and is on the outer circumference side. In some cases, it will be a negative signal.
The characteristics of the push-pull tracking error signal with respect to the track deviation amount d are the characteristics shown in FIG.
As described using (Table 1), the phase difference between the total reflection light amount signal and the push-pull tracking error signal is the beam 4
00 depends on the moving direction. Therefore, the polarity of the differential total reflection light amount signal is inverted with respect to the push-pull tracking error signal depending on the moving direction of the beam 400. When the beam 400 moves from the inner circumference to the outer circumference, or when it is on the inner circumference side of the pit 203, it becomes a negative signal as indicated by point A in FIG. 5B. When it is directly above the pit 203, it becomes 0 as shown at point B in FIG. When it is on the outer peripheral side of the pit 203, it becomes a negative signal as shown at point C in FIG.

The command device 21 outputs a positive signal as the second control signal as shown in FIG. 5C when the optical pickup 20 is moved from the inner circumference to the outer circumference.

By multiplying these by the multiplier 11, a negative multiplication signal is obtained as shown in FIG.

On the other hand, when the beam 400 exists in the reproduction-only area 5a, and the beam 400 goes from the outer circumference to the inner circumference.
The case of moving will be described with reference to FIG.

As described with reference to FIG. 5, the characteristics shown in FIG. 6A are obtained. As described with reference to FIG. 5, when the beam 400 moves from the outer circumference to the inner circumference, or when the beam 400 is on the inner circumference side of the pit 203, a positive signal as shown at point A in FIG. Becomes When it is directly above the pit 203, it becomes 0 as shown at point B in FIG. When it is on the outer peripheral side of the pit 203, it becomes a negative signal as shown at point C in FIG.

When the command device 21 moves the optical pickup 20 from the outer circumference toward the inner circumference, the command device 21 outputs a negative signal as the second control signal as shown in FIG. 6C.

By multiplying these by the multiplier 11, a negative multiplication signal is obtained as shown in FIG. 6 (d).

Therefore, the beam 4 is formed in the reproduction-only area 5a.
If 00 is present, a negative multiplication signal is obtained.

Further, the beam 400 is applied to the recordable area 5b.
Beam 40 from the inner circumference to the outer circumference.
A case where 0 moves will be described with reference to FIG.

As described with reference to FIG. 5A, the characteristics shown in FIG. 7A are obtained. As described using (Table 1), the phase difference between the total reflection light amount signal and the push-pull tracking error signal differs depending on the moving direction of the beam 400. Therefore, the polarity of the differential total reflection light amount signal is inverted with respect to the push-pull tracking error signal depending on the moving direction of the beam 400. When the beam 400 moves from the inner circumference to the outer circumference, the groove 2
When it is on the inner peripheral side of 05, it becomes a positive signal as shown at point A in FIG. When it is directly above the groove 205, it becomes 0 as shown at point B in FIG. When it is on the outer peripheral side of the groove 205, it becomes a negative signal as shown at point C in FIG. 7B.

The command device 21 outputs a positive signal as the second control signal as shown in FIG. 7C when the optical pickup 20 is moved from the inner circumference to the outer circumference.

By multiplying these by the multiplier 11, a positive multiplication signal is obtained as shown in FIG. 7 (d).

On the other hand, when the beam 400 is present in the recordable area 5b, and the beam 400 goes from the outer circumference to the inner circumference.
The case of moving will be described with reference to FIG.

As described with reference to FIG. 5, the characteristics shown in FIG. 8A are obtained. As described with reference to FIG. 7, when the beam 400 moves from the outer circumference to the inner circumference, when the beam 400 is on the inner circumference side of the groove 205, FIG.
As shown at point A in FIG. When it is directly above the groove 205, it becomes 0 as shown at point B in FIG. When it is on the outer peripheral side of the groove 205, it becomes a positive signal as shown at point C in FIG.

When the command device 21 moves the optical pickup 20 from the outer circumference to the inner circumference, it outputs a negative signal as the second control signal as shown in FIG. 8C.

By multiplying these by the multiplier 11, a positive multiplication signal is obtained as shown in FIG.

When the beam 400 is in the recordable area 5b, a positive multiplication signal is obtained. Therefore, it is possible to determine whether the beam spot is in the read-only area 5a or the recordable area 5b based on whether the multiplication signal is positive or negative.

The voltage comparator 12 compares the multiplication signal with the 0 potential, and when the multiplication signal is positive, that is, when the beam 400 is in the recordable area 5b, it is at the Hi level, and when it is negative, that is, the beam 400 is in the read-only area 5a. If there is, a low-level discrimination logic signal is output to the command device 21.

In this way, the phase comparison means 50 compares the phase of the push-pull tracking error signal, the total reflection light amount signal, and the moving direction of the beam 400, and outputs the comparison result to the command device 21.

First, at the time of normal recording and reproduction, the command device 21
The position information of each area is stored in the storage device in advance, and it is judged from the reproduced position information whether the area where the beam spot is currently located is the reproduction-only area 5a or the recordable area 5b. 3 to output to the switch 25 and the signal processing circuit 26 to obtain position information.

On the other hand, during the seek operation, the command device 21 judges the discrimination logic signal. When it is Low, it is determined that the beam 400 is in the read-only area 5a, and when it is Hi, the beam 400 is
It is possible to determine that 00 is in the recordable area 5b, output the third control signal to the third switch 25 and the signal processing circuit 26, and obtain the position information immediately after the seek operation.

Therefore, even during the seek operation, the beam 40
It is possible to determine whether 0 is in the read-only area or the recordable area, the position information can be detected at the target position of the seek operation in both areas, and the information can be recorded and reproduced. . Since the position information can be read during normal recording / reproduction, it is possible to determine whether the beam 400 is in the read-only area or the recordable area according to the position information stored in the storage device in advance. You can record and play back.

As described above, according to this embodiment, even during the seek operation, the push-pull tracking error signal, the differential total reflection light amount signal, and the second control signal indicating the moving direction of the beam 400 are input, and these signals are input. By providing the multiplier 11 that multiplies the signal and outputs the multiplication signal, it is possible to determine whether the beam 400 is in the read-only area 5a or the recordable area 5b depending on whether the multiplication signal is positive or negative. The position information can be detected immediately after the seek operation, and the information can be recorded and reproduced.

Furthermore, since the seek target position can be confirmed immediately after the seek operation is completed, the seek time can be shortened.

Further, since the determination is made based on only the radial width of the track of the disk and the unevenness, what kind of recording material 202 in the read-only area 5a and recording material 204 in the recordable area 5b can be used. However, the area can be identified.

The second embodiment of the present invention will be described with reference to FIG. In FIG. 9, 1 is a laser diode, 2 is a collimator lens, 3 is a beam splitter,
4 is an objective lens, 5 is a hybrid disc, 6 is a lens, 7 is a photodetector, 7a and 7b are photodetectors, 8 is a differential amplifier, 9 is an adder, 10 is a differentiator, 11 is a multiplier, 1
2 is a voltage comparator, 13 is a first switch, 14 is a first control circuit, 15 is a tracking actuator, 16 is a second switch, 17 is a second control circuit, 18 is a seek motor, 19 is a seek gear, 20 is an optical pickup, 2
2 is a disk motor, 25 is a third switch, 26 is a signal processing circuit, 40 is a tooth portion, 50 is a phase comparison means,
Since the above is basically the same as the constituent elements of the first embodiment described with reference to FIG. 1, the same parts are denoted by the same reference numerals and detailed description thereof will be omitted.

The output of the signal processing circuit 26 is input to 23, and the first switch 13 and the second switch 16 are input.
To the second switch 16 and a later-described fourth switch, and to the third switch 25 and the signal processing circuit 26 to the third control signal. And the output of the voltage comparator 12 is input,
A command device that outputs a fourth control signal to a storage means and a fourth switch described later. Reference numeral 27 is a storage means to which the output of the differential amplifier 8 and the control signal of the command device 23 are input. Reference numeral 28 is an inverting amplifier to which the output of the storage means 27 is input. A fourth control signal 29 receives the second control signal output from the command device 23, the output of the storage unit 27, and the fourth control signal output from the command device 23, and outputs the signal to the multiplier 11. It is a switch.

The operation of this embodiment configured as described above will be described. When performing seek operation, the command device 23
Switches the fourth switch according to the fourth control signal, and applies the second control signal to the multiplier 11. In this case, the detailed operation is omitted because it is the same as that described in the first embodiment with reference to FIG.

At the time of normal recording / reproducing, the command device 23 switches the operation of the storage means 27 by the fourth control signal, and the storage means 27 outputs the low frequency component of the tracking error signal output from the differential amplifier 8 to the hybrid disc 5. One rotation of is stored. Regarding the reproduction of the position information, the same operation as described in the first embodiment is performed.

The case where the tracking control is off during normal recording / reproduction and the position of the beam 400 is not known will be described.

The command device 23 switches the operation of the storage means 27 by the fourth control signal, ignores the input signal, and outputs a signal corresponding to the low frequency component of the tracking error signal stored during normal recording / reproduction. The inverting amplifier 28 inverts the stored tracking error signal and outputs a signal.
As described with reference to FIGS. 3 and 4, the tracking error signal becomes a positive signal when the hybrid disk 5 moves to the inner circumference side of the beam 400, and becomes a negative signal when it moves to the outer circumference side. . Therefore, the inverting amplifier 28
The signal output from is a negative signal when the hybrid disk 5 moves to the inner circumference side of the beam 400, and a positive signal when the hybrid disk 5 moves to the outer circumference side. That is, the signal output from the inverting amplifier 28 is the beam 400.
Is a signal indicating in which direction and how much the hybrid disk 5 is moved, and its polarity is the same as the polarity of the second control signal described with reference to FIGS. 5, 6, 7 and 8. Is. The fourth control signal switches the fourth switch to output the signal output from the storage means 27 to the multiplier 11. As a result, a negative multiplication signal is obtained when the beam 400 is in the read-only area 5a as described in the first embodiment with reference to FIG. Recordable area 5b
With beam 400 at, a positive multiplication signal is obtained.
The beam spot is read-only area 5 depending on whether the multiplication signal is positive or negative.
It is possible to discriminate between a and a recordable area 5b.

The voltage comparator 12 compares the multiplication signal with the 0 potential, and when the multiplication signal is positive, that is, when the beam 400 is in the recordable area 5b, it is at the Hi level, and when it is negative, that is, the beam 400 is in the read-only area 5a. If there is, a low-level discrimination logic signal is output to the command device 23.

As described above, according to the present embodiment, even if the position of the beam spot cannot be found by any means other than the seek operation, such as when the track jump operation or the tracking control is lost, the push-pull tracking error is generated. The signal, the differential total reflection light amount signal, and the output signal of the inverting amplifier 28 indicating the moving direction of the beam 400 are input, and by providing the multiplier 11 that multiplies these signals and outputs the multiplication signal, the positive and negative of the multiplication signal It is possible to determine whether the beam 400 is in the read-only area 5a or the recordable area 5b, and in either area, position information can be detected immediately after the seek operation, and recording / reproducing of information is restarted quickly. can do.

A third embodiment of the present invention will be described with reference to FIG. In FIG. 10, 1 is a laser diode, 2 is a collimator lens, 3 is a beam splitter, 4 is an objective lens, 5 is a hybrid disc, 6 is a lens, 7 is a photodetector, 7a and 7b are photodetectors, and 8 is a difference. Dynamic amplifier, 9 adder, 10 differentiator, 11 multiplier, 12 voltage comparator, 14 first control circuit, 15 tracking actuator, 16 second switch,
17 is a second control circuit, 18 is a seek motor, 19 is a seek gear, 20 is an optical pickup, 22 is a disk motor, 25 is a third switch, 26 is a signal processing circuit, 40
Is a tooth portion, and 50 is a phase comparing means. The above is basically the same as the constituent elements of the first embodiment described with reference to FIG. The description is omitted.

Reference numeral 30 is a fifth switch to which the output of the differential amplifier 8 and the second control signal and the fifth control signal of the command device described later are input. Reference numeral 31 is an inverting amplifier to which a fifth control signal output from a command device described later is input. 32
Is a sixth switch to which the output of the inverting amplifier 31 is input, and a sixth control signal and a third control signal of the command device 33, which will be described later, are input and which outputs a signal to the multiplier 11. 33
Is supplied with the output of the signal processing circuit 26, outputs a first control signal to the fifth switch 30 and the second switch 16, and outputs a second control signal to the second switch 16 and the sixth switch. Is output, a third control signal is output to the third switch 25 and the signal processing circuit 26, a fifth control signal is output to the fifth switch and the second inverting amplifier 31, and a sixth control signal is output. The command device outputs the sixth control signal to the switch 31 and the output of the voltage comparator 12 is input.

The operation of this embodiment configured as described above will be described. In case of seek operation, command device 33
Outputs 0 potential in response to the fifth control signal, and switches the fifth switch by the first control signal to apply 0 potential to the control circuit 14. The command device 33 uses the sixth control signal
And the second control signal is applied to the multiplier 11. In this case, the operation is the same as that described with reference to FIG. 1 for the first embodiment, so detailed description will be omitted.

During normal recording / reproduction, the command device 33 switches the fifth switch 30 in response to the first control signal and outputs a tracking error signal to the control circuit 14. in this case,
Operations similar to those described in the first embodiment with reference to FIG. 1 are performed.

A case will be described below in which the position of the beam 400 is not known when the tracking control is lost during normal recording / reproduction.

The command device 33 receives the fifth control signal from the first control signal.
The switch 30 is switched to add the fifth control signal to the control circuit 14. The command device 33 switches the sixth switch 6 by the sixth control signal, and adds the output of the inverting amplifier 31 to the multiplier 11. The fifth control signal is a signal for finely moving the actuator 15 in the tracking direction at a cycle sufficiently shorter than the rotation cycle, that is, the eccentric cycle. Fifth
Control signal of the actuator 15 is the beam 40.
A positive signal is output when 0 moves to the inner circumference side of the hybrid disc 5, and a negative signal is output when 0 moves to the outer circumference side. The polarity of the output of the second inverting amplifier 31 is the reverse of the polarity of the fifth control signal. A negative signal is output when the beam 400 is moved to the inner peripheral side of the hybrid disc 5, and a positive signal is output when the beam 400 is moved to the outer peripheral side. That is,
In this output signal, the beam 400 is the hybrid disc 5
On the other hand, it is a signal indicating in which direction and how much, and its polarity is the same as the polarity of the second control signal described with reference to FIGS. 5, 6, 7 and 8. As a result, a negative multiplication signal is obtained when the beam 400 is in the read-only area 5a as described in the first embodiment with reference to FIG. When the beam 400 is in the recordable area 5b, a positive multiplication signal is obtained. The beam 400 causes the read-only area 5a and the recordable area 5b depending on whether the multiplication signal is positive or negative.
It is possible to determine which of

The voltage comparator 12 compares the multiplication signal with the 0 potential, and when the multiplication signal is positive, that is, when the beam 400 is in the recordable area 5b, it is at the Hi level, and when it is negative, that is, the beam 400 is in the read-only area 5a. If there is, a low-level discrimination logic signal is output to the command device 23.

As described above, according to the present embodiment, even if the position of the beam spot cannot be determined by any operation other than the seek operation, such as when the track jump operation or the tracking control is lost, the push-pull tracking error is generated. In particular, the storage means is provided by providing the signal, the differential total reflection light amount signal, and the inverted fifth control signal indicating the moving direction of the beam 400, multiplying these signals, and outputting the multiplication signal. Even if the signal is not recorded, the beam 40
It is possible to determine whether 0 is in the read-only area 5a or the recordable area 5b, the position information can be detected immediately after the seek operation in either area, and information recording / reproduction can be restarted quickly. You can

Although the actuator 15 is moved in a cycle sufficiently shorter than the eccentric cycle in the third embodiment, the actuator 15 may be moved in a cycle sufficiently longer than the eccentric cycle.

Alternatively, the actuator 15 may be driven to move the beam spot in an eccentric cycle, and the moving direction may be moved in the same direction as the relative moving direction of the beam spot due to the eccentricity with respect to the hybrid disc 5. In this case, since the relative movement amount of the beam spot and the hybrid disc 5 due to the eccentricity can be utilized, if the relative movement amount is the same as that of the third embodiment, the driving power can be reduced.

Although the multiplier 12 is used as the phase comparing means in the first and second embodiments, the polarity of the push-pull tracking error signal is detected by the voltage comparator, and the 3-beam tracking error signal is detected by the voltage comparator. The polarity can be detected by the above, and these detection signals can be judged by the logic circuit. In this case, since no multiplier is used, there is an advantage that the circuit scale can be reduced.

Further, in the first, second and third embodiments, the photodetector 7a is used as the total reflection light amount signal detecting means of the embodiment.
The output of the photodetector 7b and the output of the photodetector 7b are added by using the adder 9. However, the low-frequency component of the information signal output from the photodetector 7 may be extracted and used, and in this case, the adder 9 is unnecessary. It can be realized with a simpler configuration.

Further, in the first, second and third embodiments, the output of the photodetector 7a and the photodetector 7b as the total reflection light amount signal detecting means is obtained by adding using the adder 9, It is also possible to detect the total reflected light amount signal by optically splitting the reflected light and providing one undivided photodetector.

This will be described with reference to FIG. In FIG. 11, 3 is a beam splitter, 5 is a hybrid disc, 4 is an objective lens, 6 is a lens, 7a is a photodetector, 7b is a photodetector, 8 is a differential amplifier, 208 is a center line of an information track, 400 Is a reflected beam, which is the same as the component shown in FIGS. 1 and 2, and therefore, is given the same reference numeral and its detailed description is omitted.

The total reflection light amount detecting means configured as described above will be described with reference to FIG. A beam splitter 91 is fixed between the beam splitter 3 and the lens 6 on the optical path of the beam 400 separated by the beam splitter 3. That is, the lens 6 is fixed on one outgoing optical path of the beam splitter 91. Reference numeral 92 is a lens fixed on the other outgoing optical path of the beam splitter 91. Reference numeral 93 is a photodetector fixed on the outgoing optical path of the lens 92.

The block diagram of FIG. 11 shows the hybrid disc 5
FIG. 3 is a radial cross-sectional view of FIG. In FIG. 11, the configuration of the optical system is omitted for the sake of simple explanation of the principle.

The beam splitter 91 converts the beam 400 into two beams.
Direction is separated at a predetermined spectral ratio. The lens 92 collects the light emitted from the beam splitter 91 and irradiates the photodetector 93 with the collected light. The photodetector 93 outputs an electric signal according to the total amount of condensed light.

Therefore, the total reflection light amount signal can be detected by providing one photodetector which is not divided.

With this configuration, an adder for obtaining the sum signal of the photodetectors 7a and 7b is unnecessary, and the electric circuit can be realized with a simpler configuration.

Further, in the first, second and third embodiments, the photodetectors are obtained by the photodetectors 7a and 7b which are divided into two in the radial direction of the hybrid disk 5 as photodetectors. It is also possible to detect the push-pull tracking error signal or the total reflection light amount signal by using the photodetector by calculating the output signal of the photodetector.

This will be described with reference to FIG. In FIG. 12, 3 is a beam splitter, 4 is an objective lens, 5 is a hybrid disc, 6 is a lens, 8 is a differential amplifier, and 9 is an adder, which are the same as the configurations shown in FIGS. 1 and 2. The same numbers are given and detailed explanations are omitted.

In FIG. 12, 95a, 95b, 95c
Reference numerals 95d and 95d denote photodetectors fixed on the exit optical path of the lens 6. These are divided in the radial direction of the hybrid disc 5, and also in the circumferential tangential direction of the hybrid disc 5. That is, these form a four-division photodetector.

Reference numeral 95a designates a photodetector fixed on the inner side of the circle. Reference numeral 95b is a photodetector fixed on the outer rotation side. Reference numeral 95c is a photodetector fixed on the reverse rotation side in the circle. Reference numeral 95d is a photodetector fixed on the outer side of the direction of reverse rotation.

Reference numeral 96 indicates the output of the photodetector 95a and the photodetector 9
The output of 5c is input, and the output is an adder in which the non-inverting input of the differential amplifier 8 and the adder 9 are input. Reference numeral 97 is an adder to which the output of the photodetector 95b and the output of the photodetector 95d are input, and the output of which is input to the inverting input of the differential amplifier 8 and the adder 9.

The configuration diagram of FIG. 12 shows the hybrid disc 5
FIG. 3 is a radial cross-sectional view of FIG. In FIG. 12, the configuration of the optical system is omitted for simplicity of explanation of the principle.

The push-pull tracking error signal detection means and the total reflection light amount detection means configured as described above will be described. As described with reference to FIG. 2, the reflected light from the hybrid disc 5 is converted into a signal according to the amount of light by the photodetectors divided in the radial direction.

The amount of light incident on 7a in the configuration of FIG. 2 enters the photodetectors 95a and 95c. The adder 96 outputs the output signal of the photodetector 95a and the photodetector 95c.
And an output signal of the above are added to detect a signal corresponding to the amount of light on the inner circumferential side divided in the radial direction.

Similarly, in the configuration of FIG. 2, the amount of light incident on 7b is incident on the photodetectors 95b and 95d. The adder 97 adds the output signal of the photodetector 95b and the output signal of the photodetector 95d, and detects a signal according to the amount of light on the radially inner side which is divided in the radial direction.

The differential amplifier 8 outputs a difference signal between the output signal of the adder 96 and the output signal of the adder 97. This is a signal according to the difference between the amount of reflected light on the inner circumference side and the amount of reflected light on the outer circumference side. Therefore, the differential amplifier 8 outputs the push-pull tracking error signal as described with reference to FIG.

The adder 9 outputs the sum signal of the output signal of the adder 96 and the output signal of the adder 97. This is a signal corresponding to the total amount of reflected light. Therefore, the adder 9 outputs the total reflection light amount signal as described with reference to FIG.

A detailed description is omitted because it is not directly related to the object of the present invention, but the four-division photodetector having this configuration uses the astigmatism method to control the focusing of the objective lens in the optical axis direction. May be used for.

With this structure, even if a large number of photodetectors are used for other purposes, the regions can be discriminated in the same manner as shown in the embodiment.

Further, as described with reference to FIG. 15 in the first, second and third embodiments, the hybrid disc 5 has the reproduction-only area formed by the pits 203 whose information track width is ½ or less of the track pitch. 5a, and the information recording mark 206 is provided in the wide groove 205 in which the width of the information track is 1/2 or more. As described in detail in the embodiment, the determination is made based on only the radial width and the unevenness of the track of the disc regardless of the information recording method.

Instead of the reproduction-only area 5a, it is also possible to discriminate the areas of the recording system as shown in FIGS. 13 (a), 13 (b) and 13 (c).

FIG. 13A shows an example in which a pit 210 having a concave shape with respect to the side irradiated with the light beam and having a width of ½ or more of the track pitch is recorded.

FIG. 13B shows an example in which the information signal mark 206 is recorded in a groove which is convex toward the side irradiated with the light beam and has a width of ½ or less of the track pitch.
Instead of the information recording mark 206, a concave or convex pit may be used.

FIG. 13C shows an example in which the information signal mark 206 is recorded on a land which is concave with respect to the side irradiated with the light beam and has a width of ½ or more of the track pitch. Instead of the information recording mark 206, a concave or convex pit may be used.

In these regions, the push-pull tracking error signal and the total reflection light amount signal having the same phase as the read-only region 5a described in the embodiment can be obtained.

In addition, instead of the recordable area 5b, as shown in FIG.
It is possible to discriminate even in the areas of the recording methods as shown in (a), (b) and (c) of 4.

FIG. 14A shows an example in which the information signal mark 206 is recorded on a land which is concave with respect to the side irradiated with the light beam and has a width of ½ or less of the track pitch. Instead of the information recording mark 206, a concave or convex pit may be used.

FIG. 14B shows an example in which a pit 211 having a width of ½ or more of the track pitch is recorded, which is convex toward the side irradiated with the light beam.

FIG. 14C shows an example in which a pit 212 having a width which is concave with respect to the side irradiated with the light beam and has a width of ½ or less of the track pitch is recorded.

In these areas, the push-pull tracking error signal and the total reflection light amount signal having the same phase as that of the recordable area 5b described in the embodiment can be obtained. Figure 1
In (c) of 5, a concave or convex pit may be used instead of the information recording mark 206.

Although the multiplier 12 is used as the phase comparison means in the first, second and third embodiments, the polarity of the push-pull tracking error signal is detected by the voltage comparator and the total reflection light amount signal signal is obtained. The polarity can be detected by the voltage comparator, and these detection signals can be judged by the logic circuit. In this case, since no multiplier is used, there is an advantage that the circuit scale can be reduced.

Although the phase of the totally reflected light amount signal is changed by using the differentiator 10 in the first, second and third embodiments, it is possible to directly compare the phases or to obtain the push-pull tracking error signal. It goes without saying that the present invention can be realized by a configuration in which the phase is changed and the phase is compared, or by a configuration in which the phase is changed by another component capable of changing the phase and then the phase is compared.

Further, in the first, second and third embodiments, the signal indicating the moving direction of the beam 400 is multiplied by the multiplier 11
However, it is also possible to realize the configuration in which the command device 21 determines the area based on the phase comparison result of the push-pull tracking error signal and the total reflection light amount signal and the moving direction of the beam 400. There is no end.

In the first, second and third embodiments, the push-pull tracking error signal is transmitted to the beam 40.
It goes without saying that it is also possible to realize the configuration in which the polarity is inverted by the signal indicating the moving direction of 0 and the phase is compared with the total reflection light amount signal.

Further, in the first, second and third embodiments, it is also possible to realize a configuration in which the polarity of the totally reflected light amount signal is inverted by the signal indicating the moving direction of the beam 400 and the phase is compared with the push-pull tracking error signal. Needless to say.

Further, in the first, second and third embodiments, the voltage comparator 12 determines the polarity when the amplitude of the multiplication signal is equal to or more than a certain value.
Even if there is a noise or a detection error of the tracking error signal, the polarity of the multiplication signal can be stably determined.

Further, in the first, second and third embodiments, when the push-pull tracking error signal is below a certain value, the latch circuit is provided so as to retain the result of judging the polarity and not change it. Even if there is a detection error in the tracking error signal or the tracking error signal, the polarity of the multiplication signal can be stably determined.

Further, in the first, second and third embodiments, by providing a latch circuit or the like so as to retain the result of judging the polarity and not change it when the differential signal of the total reflected light amount signal is below a certain value. The polarity of the multiplication signal can be stably determined even if there is noise or a detection error in the tracking error signal.

Further, in the first, second and third embodiments, means for differentiating the push-pull tracking error signal is provided, and when the signal indicating the inclination of the push-pull tracking error signal of the output is below a certain value, the polarity is set. By providing a latch circuit or the like so as to hold the result of the determination and not to change it, the polarity of the multiplication signal can be stably determined even if there is noise or a detection error of the tracking error signal.

In the first, second and third embodiments, the second control signal output from the command device 21 is used as the signal indicating the moving direction of the beam 400. It is also possible to realize a configuration in which phase comparison is performed without using the second control signal indicating the moving direction of the beam 400 by limiting the direction. In this case, the movement direction of the beam 400 is indirectly taken into consideration for the determination. According to this configuration, it is possible to use a 2-input multiplier instead of the 3-input multiplier like the multiplier 11, and there is an advantage that it can be realized with a simple configuration.

Further, in the first embodiment, the seek operation is performed for a relatively long distance, but it is also possible to make the determination by performing a relatively short distance track jump operation. Even in this case, it is possible to move sufficiently between the regions, so it is useful to be able to distinguish the regions.

Needless to say, it is possible to make a judgment even in the case of jumping one track and repetitively reproducing one track on an optical disk having a spiral track.

In the second and third embodiments, the case where the tracking control is off during normal recording / reproducing has been described, but with the same configuration and operation, before the tracking control is applied after the seek operation or the track jump operation. It is also possible to discriminate the area. In this case, since it is not necessary to perform the process of discriminating the area from the address information, it is possible to shorten the time until the start of the normal recording / reproducing operation.

In the second and third embodiments, the case where the tracking control is off during normal recording / reproducing has been described. However, with the same configuration and operation, it is possible to perform normal recording / reproducing for the first time after the power is turned on or under low power consumption. It is also possible to discriminate the area before performing the tracking control for the first time, for example, by a standby operation by stopping the function for. In this case, since it is not necessary to read the address information, store the address information and discriminate the area from the information, it is possible to shorten the time until the start of the normal recording / reproducing operation and eliminate the need for providing a storage device.

[0124]

As described above, the present invention compares the phase of the push-pull tracking error signal with the phase of the total reflection light amount signal, and based on the moving direction of the beam spot and the phase comparison result, the width of the information track is changed to the track pitch. Area 1 which is less than 1/2 of the area and the width of the information track is 1 / of the track pitch.
It is possible to realize an excellent optical disk device capable of discriminating which of the two or more areas 2 is in the seek operation.

[Brief description of drawings]

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

FIG. 2 is a block diagram for explaining the principles of a push-pull tracking error detection method and a total reflection light amount detection method in the same embodiment.

FIG. 3A is a block diagram showing the relationship between the position of the same groove and beam spot and the intensity of reflected light. FIG. 3B is a block diagram showing the relationship between the position of the same groove and beam spot and the intensity of reflected light. ) Is a block diagram showing the relationship between the position of the groove and the beam spot and the intensity of the reflected light. (D) is a characteristic diagram showing the relationship between the track shift amount d of the groove and the beam spot and the push-pull tracking error signal (e). A characteristic diagram showing the relationship between the track deviation amount d of the groove and the beam spot and the total reflection light amount signal.

FIG. 4A is a block diagram showing the relationship between the position of the pit and the beam spot and the intensity of the reflected light. FIG. 4B is a block diagram showing the relationship between the position of the pit and the beam spot and the intensity of the reflected light. ) Is a block diagram showing the relationship between the position of the pit and the beam spot and the intensity of the reflected light. (D) is the track shift amount d between the pit and the beam spot.
And (e) is a characteristic diagram showing the relationship between the push-pull tracking error signal and the track deviation amount d between the pit and the beam spot.
And characteristic graph showing the relationship between total reflection light amount signal

FIG. 5 is a characteristic diagram of a multiplication signal when the beam moves from the inner circumference to the outer circumference in the reproduction-only area.

FIG. 6 is a characteristic diagram of a multiplication signal when the beam moves from the outer circumference to the inner circumference in the reproduction-only area.

FIG. 7 is a characteristic diagram of a multiplication signal when the beam moves from the inner circumference to the outer circumference in the same recordable area.

FIG. 8 is a characteristic diagram of a multiplication signal when the beam moves from the outer circumference to the inner circumference in the same recordable area.

FIG. 9 is a block diagram showing the configuration of an optical disc device according to a second embodiment of the present invention.

FIG. 10 is a block diagram showing the configuration of an optical disc device according to a third embodiment of the present invention.

FIG. 11 is a block diagram for explaining the principles of a push-pull tracking error detection method and a total reflection light amount detection method.

FIG. 12 is a block diagram for explaining the principles of a push-pull tracking error detection method and a total reflection light amount detection method.

13A is an enlarged perspective view of an information track, FIG. 13B is an enlarged perspective view of an information track, and FIG. 13C is an enlarged perspective view of an information track.

14A is an enlarged perspective view of an information track, FIG. 14B is an enlarged perspective view of an information track, and FIG. 14C is an enlarged perspective view of an information track.

15A is a front view showing the structure of a hybrid disc, FIG. 15B is a perspective view in which an information track in the read-only area is enlarged, and FIG. 15C is a perspective view in which an information track in the recordable area is enlarged.

FIG. 16 is a block diagram showing a configuration of a conventional optical disc device.

[Explanation of symbols]

 7 Photodetector 7a, 7b, 7c, 7d Photodetector 8 Differential amplifier 9 Adder 10 Differentiator 11 Multiplier 12 Voltage comparator 13 Switch 14 Tracking actuator control circuit 15 Tracking actuator 16 Switch 17 Seek motor control circuit 18 Seek Motor 19 Seek gear 20 Optical pickup 22 Disk motor 24 Command device 50 Phase comparison means

Claims (3)

[Claims] 1. The width of the information track is 1 of the track pitch.
An optical disk device comprising an optical disk having a first area equal to or less than / 2 and a second area having a width of an information track equal to or greater than 1/2 of a track pitch, the reflection of a light beam applied to the optical disk. A first photodetector, which is divided and arranged so as to receive light and detect a tracking error by the push-pull method, and a signal output from the first photodetector is input to detect the tracking error by the push-pull method. A first detection unit for detecting the total reflection light amount signal according to the light amount of the reflected light of the light beam applied to the optical disc, which is also used or independently of the first photodetector; Depending on the polarity of the signal indicating the moving direction of the spot,
And a phase comparison unit that compares the phase of the tracking error signal output from the first detection unit with the phase of the total reflection light amount signal output from the second detection unit. Output from the phase comparison unit An optical disk device, wherein it is determined whether the beam spot is in the area 1 or the area 2 based on the phase comparison signal. 2. The optical disc according to claim 1, further comprising a storage unit for storing the tracking error signal information at the time of recording and reproducing, and detecting the moving direction of the beam spot with respect to the optical disc by the information stored in the storage unit. apparatus. 3. A beam spot is moved in the radial direction of the optical disc in a cycle that does not match the eccentricity cycle, or in the radial direction of the optical disk in the same phase as the moving direction of the beam spot due to eccentricity in the eccentricity cycle with respect to the optical disk. 2. The optical disk device according to claim 1, wherein the moving direction of the beam spot is detected by moving the beam spot.