JPH06150337A - Optical disk recording and reproducing device - Google Patents

Abstract

PURPOSE:To enable moving quickly and reliably an optical pickup from a pit region to a group region or from the group region to the pit region by discriminating either of the pit region or the group region is irradiated with a light beam. CONSTITUTION:The optical disk recording and reproducing device irradiates an optical disk 1 having a pit region and a group region with a light beam 50, and performes recording and reproducing of information while tracking basing on a tracking error signal S1. A region discriminating circuit 20 of an envelop detecting circuit which outputs a region discriminating signal S3 indicating that either of the pit region or the group region is irradiated with the light beam 50 basing on a level of the tracking error signal S1, is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk recording / reproducing apparatus for recording / reproducing information on / from an optical disk having a track formed by pits and a track formed by grooves.

[0002]

2. Description of the Related Art As shown in FIG.
In the optical disc 101 having the track formed by 1 ... and the track formed by the groove 152, the pit area is used only for reproduction and the groove area is used for recording and reproduction. Usually, in the pit area, physical information such as the reflectance of the optical disc 101, the optical power required for recording, and the recordable area is recorded in advance. Therefore, when using the optical disc 101, it is essential to read the information in the pit area. On the other hand, the user can freely record information in the groove area.

An example of an optical disk recording / reproducing apparatus for recording / reproducing information using the above optical disk 101 is shown in FIG.
Shown in.

From the optical pickup 102 to the optical disk 10
1 is irradiated with the light beam 150, and the reflected light from the optical disc 101 returns to the optical pickup 102 again and is converted into an electric signal. Based on this electric signal, the tracking error signal generation circuit 103 generates a tracking error signal S1 for tracking servo. The tracking error signal S1 is sent to the phase compensation circuit 111 and the low-pass filter 112 via the switch 109 for switching the polarity and the switch 110 for turning on / off the tracking servo.

The controller 116 has a switch 109.
As described later, the polarity of the tracking error signal S1 is switched by switching the polarity of the inverting amplifier 106 as required.
Invert by. Further, the controller 116 controls the switch 110 to select ON / OFF of the tracking servo.

The output of the phase compensation circuit 111 is the drive circuit 11
Sent to 4. The drive circuit 114 drives an actuator (not shown) for causing the light beam to follow the track.

The output of the low pass filter 112 is sent to the drive circuit 115. The drive circuit 115 drives a feeding mechanism (not shown) that moves the optical pickup 102 in the radial direction of the optical disc 101. Switch 1
If the tracking servo is turned off by 10,
The drive circuit 115 sets the optical pickup 102 to the optical disc 1 according to the applied voltage from the sending voltage applying circuit 113.
The feed mechanism is driven so as to move to the inner peripheral side or the outer peripheral side of 01. The controller 116 controls the feed voltage application circuit 113 to determine the applied voltage.

The outputs of the drive circuits 114 and 115 are fed back to the optical pickup 102.

When the pre-recorded information is recorded in the groove of the optical disc 101, the pre-recorded information detection circuit 104 detects the pre-recorded information signal S from the electric signal from the optical pickup 102.
Extract 4. The absolute address detection circuit 107 obtains the absolute address of the optical disc 101 from the advance information signal S4. The controller 116 controls access by the drive circuit 114 based on the absolute address.

The reproduction signal arithmetic circuit 105 reproduces the information recorded on the track from the electric signal from the optical pickup 102. The controller 116 controls the reproduction signal arithmetic circuit 105 to change the arithmetic processing method between the case of reproducing the information of the pit area and the case of reproducing the information of the groove area. The reproduction signal S11 from the reproduction signal calculation circuit 105 is sent to the reproduction data processing circuit 108, where digital data is obtained. Some of the digital data is sent to controller 116.

Using the above optical disk recording / reproducing apparatus,
FIG. 13B shows a tracking error signal S1 obtained from the vicinity of the boundary between the pit area and the groove area of the optical disc 101 (FIG. 13A). The reproduction signal S11 of the pit information obtained from the reproduction signal calculation circuit 105 is shown in FIG. The tracking error signal S1 is obtained by the 3-beam method.

The track interval of the optical disc 101 is generally 1.6 μm in both the pit area and the groove area.
The width of the pit 151 is 0.7 μm or less, and the groove 15
The width of 2 is 1.0 μm or more. The diameter of the light beam 150 is about 1.0 μm. Therefore, in the pit area, the light beam 150 becomes a just track at the zero cross point where the tracking error signal S1 shifts from the peak to the valley, but in the groove area, the tracking error signal S1 shifts from the valley to the peak at the zero cross point. Light beam 150
Will be the just track.

Therefore, when shifting from the pit area to the groove area, the tracking servo is temporarily turned off by the switch 110 based on a command from the controller 116, and in this state, the voltage is applied from the feed voltage applying circuit 113 to the drive circuit 115. The optical pickup 102 is applied for a predetermined time.
Is moved to the groove area by the feed mechanism. When the movement is completed, the switch 109 is set to the inverting amplifier 10
The polarity of the tracking error signal S1 is inverted by switching to the 6 side. Then, the switch 110 turns on the tracking servo.

When moving from the groove area to the pit area, a process reverse to the above process is executed.

Thus, in both the pit area and the groove area, the light beam 150 is just at the zero cross point where the tracking error signal S1 shifts from the peak to the valley.
Become a truck. Therefore, tracking becomes easy.

[0016]

However, in the above conventional configuration, the optical pickup 102 is driven by the feed voltage applying circuit 113 in order to surely move the optical pickup 102 from the pit area to the groove area or from the groove area to the pit area. The voltage is applied to the circuit 115 for a long time. For this reason,
There is a problem that the processing time becomes slow and the access time also becomes slow.

[0017]

In order to solve the above-mentioned problems, an optical disk recording / reproducing apparatus according to the invention of claim 1 irradiates an optical disk having a pit area and a groove area with a light beam to obtain a tracking error signal. In an optical disc recording / reproducing apparatus for recording / reproducing information while tracking based on the area, an area for outputting an area discrimination signal indicating whether a light beam is irradiated to a pit area or a groove area based on the level of a tracking error signal. It is characterized in that a discrimination circuit is provided.

In order to solve the above-mentioned problems, an optical disk recording / reproducing apparatus according to a second aspect of the present invention irradiates an optical disk having a pit area and a groove area with a light beam,
In an optical disc recording / reproducing apparatus for recording / reproducing information while tracking based on a tracking error signal, an area information signal indicating whether the light beam is applied to a pit area or a groove area is a prior information signal obtained from the groove area. Alternatively, it is characterized in that an area discriminating circuit for outputting based on the presence or absence of a reproduction signal of pit information obtained from the pit area is provided.

In order to solve the above-mentioned problems, an optical disk recording / reproducing apparatus according to a third aspect of the present invention is the optical disk recording / reproducing apparatus according to the first or second aspect, wherein the area discrimination signal is at least the optical disk. It is characterized in that a region determining circuit is provided which outputs a region determining signal indicating whether the light beam is applied to the pit region or the groove region when the time required for one rotation is unchanged.

In order to solve the above problems, an optical disk recording / reproducing apparatus according to a fourth aspect of the present invention is the optical disk recording / reproducing apparatus according to claim 1 or 2, wherein the pit is based on the area discrimination signal. It is characterized in that a control means for turning on / off the servo is provided so as to track the light beam to a desired area, either the area or the groove area.

[0021]

According to the structure of the first aspect, it is possible to determine whether the light beam is applied to the pit area or the groove area. Therefore, the optical pickup is moved from the pit area to the groove area or from the groove area to the pit area. It will be possible to move to the area quickly and reliably.

According to the configuration of claim 2, there is an operation similar to that of claim 1.

According to the structure of claim 3, in addition to the effects of claims 1 and 2, even when the optical disc is eccentric, the optical pickup is moved from the pit area to the groove area.
Alternatively, it is possible to move from the groove area to the pit area quickly and reliably.

According to the structure of claim 4, in addition to the effects of claims 1 and 2, even if the optical disk is eccentric, the light beam is tracked to a desired area of either the pit area or the groove area. be able to.

[0025]

FIG. 1 and FIG. 2 show a first embodiment of the present invention.
The explanation is based on the following.

As shown in FIG. 1, the optical disk recording / reproducing apparatus of the present embodiment irradiates the optical disk 1 with a light beam 50, receives the reflected light from the optical disk 1 and converts it into an electric signal. , A tracking error signal S for tracking servo based on the electric signal
1 and a inverting amplifier 6 for inverting the polarity of the tracking error signal S1.
A switch 9 for switching the polarity of the tracking error signal S1 and a switch 10 for turning on / off the tracking servo.

Further, the optical disc recording / reproducing apparatus includes a phase compensating circuit 1 for compensating the phase of the tracking error signal S1.
1, an actuator drive circuit 14 that drives a tracking actuator (not shown) based on the output of the phase compensation circuit 11, and a low-pass filter 1 that extracts the low-frequency component of the tracking error signal S1.
2, a feed mechanism drive circuit 15 that drives a feed mechanism (not shown) that moves the optical pickup 2 in the radial direction of the optical disc 1 based on the output of the low-pass filter 12, and a tracking servo is turned off by a switch 10. At this time, a feed voltage application circuit 13 is provided for applying a voltage for moving the optical pickup 2 to the inner circumference side or the outer circumference side of the optical disc 1 to the feed mechanism drive circuit 15.

Further, the optical disk recording / reproducing apparatus has a prerecorded information detection circuit 4 for extracting the prerecorded information prerecorded in the groove based on the electric signal from the optical pickup 2.
An absolute address detection circuit 7 for obtaining an absolute address of the optical disc 1 from the prior information, a reproduction signal calculation circuit 5 for extracting a reproduction signal from an electric signal from the optical pickup 2,
The reproduction data processing circuit 8 for converting the reproduction signal into digital data and the access control based on the absolute address from the absolute address detection circuit 7 are performed, and the optical disk 1
The controller 16 is provided for performing processing such as changing the arithmetic processing method of the reproduction signal arithmetic circuit 5 depending on whether the information of the pit area is reproduced or the information of the groove area is reproduced.

The optical disc recording / reproducing apparatus of this embodiment further has an area discriminating circuit for discriminating whether the light beam 50 is located in the pit area or the groove area of the optical disk 1. ing. The area discriminating circuit includes a reference voltage source 17, a comparator 18, and a retriggerable one-shot circuit 19 to which a resistor R1 and a capacitor C1 are externally attached.

The reference voltage (V _ref1 ) output from the reference voltage source 17 is the tracking error signal S in the pit area.
The voltage is set higher than the peak level of 1 and smaller than the peak level of the tracking error signal S1 in the groove area. Since the pit area has a pit portion and a non-pit portion (mirror portion), the signal amount of the tracking error signal S1 is smaller than that of the groove area. Therefore, the peak level of the tracking error signal S1 in the pit area is smaller than the peak level of the tracking error signal S1 in the groove area.

The comparator 18 compares the voltage of the tracking error signal S1 from the tracking error signal generating circuit 3 with the reference voltage from the reference voltage source 17. The output signal S2 of the comparator 18 becomes high level when the voltage of the tracking error signal S1 is larger than the reference voltage.

The retriggerable one-shot circuit 19 is
Based on the output signal S2 of the comparator 18, the area discrimination signal S3
Is output. The area discrimination signal S3 becomes high level at the rising edge of the output signal S2 of the comparator 18. The period in which the area discrimination signal S3 maintains the high level is set by the resistor R1 and the capacitor C1 as described later.

In the above structure, when the light beam 50 crosses the boundary between the pit area and the groove area, the tracking error signal S1 changes as shown in FIG. 2 (a). When the tracking error signal S1 is input to the comparator 18, the output signal S2 of the comparator 18 becomes a low level in the pit area and becomes a narrow pulse train in the groove area, as shown in FIG. Become.

When the output signal S2 of the comparator 18 is input to the retriggerable one-shot circuit 19, the pulse train 1
Area discrimination signal S3 at the rising edge of the th pulse
Becomes high level, as shown in FIG. The period during which the area discrimination signal S3 maintains the high level is set to be longer than the pulse interval of the pulse train.
Therefore, the area discrimination signal S3 maintains a high level while the pulse train is being input from the comparator 18. When the last pulse of the pulse train is input to the retriggerable one-shot circuit 19, the area discrimination signal S3 remains at high level for a certain period of time and then becomes low level.

As described above, when the light beam 50 is located in the pit area, the area discrimination signal S3 becomes low level, and when the light beam 50 is located in the groove area, the area discrimination signal S3 is high. Become a level. Therefore, the pit area and the groove area can be discriminated from each other according to the level of the region discrimination signal S3.

The switch 9 for switching the polarity of the tracking error signal S1 can be automatically controlled by the area discrimination signal S3. That is, when the light beam 50 is located in the pit area, the polarity of the tracking error signal S1 is not inverted, and when the light beam 50 is located in the groove area,
The tracking error signal S1 is inverted by the inverting amplifier 6.

Further, the area discrimination signal S3 enables the controller 16 to recognize the area where the optical pickup 2 is located. This makes the controller 1
6 can move the optical pickup 2 to the pit area or the groove area quickly.

The second embodiment of the present invention will be described below with reference to FIGS. 3 to 5. For convenience of explanation, members having the same functions as those of the members shown in the drawings of the above-described embodiments are designated by the same reference numerals, and the description thereof will be omitted.

The optical disc recording / reproducing apparatus according to the present embodiment and the optical disc recording / reproducing apparatus according to the above-described embodiments are different in the configuration of the area discriminating circuit. As shown in FIG. 3, the area discriminating circuit of this embodiment includes an envelope detection circuit 20 and a reference voltage source 2
1 and a comparator 22.

The envelope detection circuit 20 performs envelope detection of the advance information signal S4 (wobbling signal) output from the advance recording information detection circuit 4, and detects the detection signal S5 by the comparator 22.
Output to.

The reference voltage (V _ref2 ) output from the reference voltage source 21 is set to a voltage smaller than the voltage of the detection signal S5 in the groove area.

The comparator 22 compares the voltage of the detection signal S5 from the envelope detection circuit 20 with the reference voltage from the reference voltage source 21, and outputs the area discrimination signal S6. When the voltage of the detection signal S5 is larger than the reference voltage, the area discrimination signal S6 is
Become high level.

In the above structure, as shown in FIG.
By wobbling the groove 52 of the optical disc 1, a pre-information signal S4 is obtained when the light beam 50 crosses the groove 52 ... When an absolute address is pre-recorded in the groove 52. Since there is no wobbling in the pit area where the pits 51 are formed, the advance information signal S4 cannot be obtained.

Therefore, when the light beam 50 crosses the boundary between the pit area and the groove area, the advance information signal S4
Changes as shown in FIG. This prior information signal S
4 is input to the absolute address detection circuit 7 and the envelope detection circuit 20. The envelope detection circuit 20 obtains a detection signal S5 as shown in FIG.

The detected signal S5 is compared with the reference voltage by the comparator 22. Since the voltage of the detection signal S5 is higher than the reference voltage in the groove area, the area discrimination signal S6 becomes high level as shown in FIG. On the other hand, in the pit area, since the voltage of the detection signal S5 is smaller than the reference voltage, the area discrimination signal S6 becomes low level.

As described above, when the light beam 50 is located in the pit area, the area discrimination signal S6 becomes low level, and when the light beam 50 is located in the groove area, the area discrimination signal S6 is high. Become a level. Therefore, the pit area and the groove area can be discriminated from each other according to the level of the region discrimination signal S6.

Therefore, the same effect as that of the above embodiment can be obtained.

The third embodiment of the present invention will be described below with reference to FIGS. 6 and 7. For convenience of explanation, members having the same functions as those of the members shown in the drawings of the above-described embodiments are designated by the same reference numerals, and the description thereof will be omitted.

The optical disc recording / reproducing apparatus according to the present embodiment and the optical disc recording / reproducing apparatus according to the above-described embodiments are different in the configuration of the area discriminating circuit. The area discriminating circuit of this embodiment is shown in FIG.
As shown in, the envelope detection circuit 26 and the reference voltage source 27
And a comparator 28.

The envelope detection circuit 26 performs the envelope detection of the reproduction signal S11 of the pit information output from the reproduction signal calculation circuit 5, and outputs the detection signal S12 to the comparator 28.

The reference voltage (V _ref3 ) output from the reference voltage source 27 is set to a voltage smaller than the voltage of the detection signal S12 in the pit area.

The comparator 28 compares the voltage of the detection signal S12 from the envelope detection circuit 26 with the reference voltage from the reference voltage source 27, and outputs the area discrimination signal S13. The area discrimination signal S13 becomes low level when the voltage of the detection signal S12 is higher than the reference voltage.

In the above structure, the optical pickup 2
The electric signals S7 and S8 are input to the reproduction signal calculation circuit 5 (see FIG. 1). The reproduction signal calculation circuit 5 includes a differential amplifier 23, an addition amplifier 24, and a switch 25, and the difference signal S9 and the sum signal S10 of the electric signals S7 and S8 are obtained respectively.

In the pit area, the electric signals S7 and S8 are in phase with each other. Therefore, the difference signal S9 becomes almost zero, and only the sum signal 10 is obtained. On the other hand, in the groove area of the magneto-optical disk (optical disk 1), the electric signal S7
S8 is in opposite phase to each other. Therefore, only the difference signal S9 is obtained, and the sum signal 10 becomes almost zero.

Therefore, in the pit area, the sum signal S10
Is output as a reproduction signal S11 of the pit information, and the difference signal S9 is reproduced in the groove area as the reproduction signal S1 of the magneto-optical recording information.
The controller 16 switches the switch 25 so as to output as 1.

The sum signal S10 is the reproduction signal S1 of the pit information.
When it is output as 1, when the light beam 50 crosses the boundary between the pit area and the groove area, the reproduction signal S11 of the pit information changes as shown in FIG. 7A. The reproduction signal S11 of the pit information is reproduced by the reproduction data processing circuit 8
And the envelope detection circuit 26. The envelope detection circuit 26 obtains a detection signal S12 as shown in FIG.

The detected signal S12 is compared with the reference voltage by the comparator 28. In the pit area, since the voltage of the detection signal S12 is higher than the reference voltage, the area discrimination signal S13 becomes low level as shown in FIG. On the other hand, in the groove area, the voltage of the detection signal S12 is smaller than the reference voltage, so that the area determination signal S13 becomes high level.

As described above, when the light beam 50 is located in the pit area, the area discrimination signal S13 becomes low level, and when the light beam 50 is located in the groove area, the area discrimination signal S13 is high. Become a level. Therefore, the pit area and the groove area can be discriminated from each other according to the level of the region discrimination signal S13.

Therefore, the same effect as that of the above embodiment can be obtained.

The fourth embodiment of the present invention will be described below with reference to FIGS. 8 and 9. For convenience of explanation, members having the same functions as those of the members shown in the drawings of the above-described embodiments are designated by the same reference numerals, and the description thereof will be omitted.

The area discriminating circuit of the optical disk recording / reproducing apparatus of this embodiment is the same as the area discriminating circuit of the first to third embodiments.
The configuration is such that a region determination circuit including the retriggerable one-shot circuit 29, the AND gate 30, and the ExOR gate 33 of FIG. 8 is added.

The retriggerable one-shot circuit 29 is
It has an external resistor R2 and a capacitor C2.

In the above structure, the area discrimination signal S3 of the first embodiment, the area discrimination signal S6 of the second embodiment, and the third area discrimination signal S6 of the second embodiment.
The area discrimination signal S14 corresponding to any of the area discrimination signals S13 of the embodiment is the retriggerable one-shot circuit 29.
Entered in.

When the optical disc 1 is eccentric, the light beam 50 moves back and forth in the vicinity of the boundary between the pit area and the groove area. Therefore, the area discrimination signal S
As shown in FIG. 9A, 14 is a pulse train that alternately switches between a high level and a low level.

This area discrimination signal S14 is retriggerable.
When input to the one-shot circuit 29, a retriggerable
The output signal S15 of the one-shot circuit 29 becomes low level at the rising edge of the first pulse of the pulse train. The period (T _time ) during which the output signal S15 maintains the low level is determined by the resistor R2 and the capacitor C2, and is set to be longer than the time required for the optical disc 1 to rotate once. Therefore, until the final pulse of the area discrimination signal S14 is input, the output signal S1
No. 5 maintains low level. When the last pulse of the pulse train is input to the retriggerable one-shot circuit 29, the output signal S15 maintains a low level for a certain period of time and then becomes a high level, as shown in FIG.

The AND gate 30 outputs the area discrimination signal S14.
And the output signal S1 of the retriggerable one-shot circuit 29
The logical product of 5 is obtained, and this is used as the groove area determination signal S16.
Output as. Therefore, the groove area determination signal S
16 is a pit area, as shown in FIG.
It becomes low level in the area near the boundary between the pit area and the groove area and where the light beam 50 moves back and forth due to the eccentricity of the optical disk 1, and becomes high level in the other groove areas.

The ExOR gate 33 outputs the output signal S15 of the retriggerable one-shot circuit 29 and the AND gate 3
The exclusive OR of the groove area determination signal S16 from 0 is obtained, and this is output as the pit area determination signal S17. Therefore, the pit area determination signal S17 has a low level in the groove area and in the area near the boundary between the pit area and the groove area where the light beam 50 moves back and forth due to the eccentricity of the optical disk 1, as shown in FIG. And becomes high level in other pit areas.

The groove area determination signal S16 and the pit area determination signal S17 are input to the controller 16. As a result, even if the optical disc 1 is eccentric, it is possible to recognize that the optical pickup 2 has certainly reached the target pit area or groove area.

Fifth Embodiment of the Invention FIGS. 10 and 11
The explanation is based on the following. For convenience of explanation, members having the same functions as those of the members shown in the drawings of the above-described embodiments are designated by the same reference numerals, and the description thereof will be omitted.

The area discriminating circuit of the optical disk recording / reproducing apparatus of this embodiment is the same as the area discriminating circuit of the first to third embodiments.
The configuration is such that a control means including the ExOR gate 31 and the OR gate 32 of FIG. 10 is added.

In the above structure, the area discrimination signal S3 of the first embodiment, the area discrimination signal S6 of the second embodiment and the third area discrimination signal S6 of the second embodiment.
The area discrimination signal S14 corresponding to any of the area discrimination signals S13 of the embodiment is the retriggerable one-shot circuit 29.
Entered in.

When the optical disc 1 is eccentric, the area discrimination signal S14 is a pulse train which alternately switches between a high level and a low level, as shown in FIG. 11A, as in the above embodiment.

The area discrimination signal S14 is inputted to the polarity changeover switch 9, and the polarity of the tracking error signal S1 is automatically changed over in accordance with the pit area or the groove area. The area discrimination signal S14 is also input to the ExOR gate 31.

The ExOR gate 31 receives the area discrimination signal S1.
4 and the area designating signal S18 from the controller 16 are obtained by exclusive OR, and this is output as an output signal S19. The area designating signal S18 is set to a low level when the tracking servo is drawn in the pit area, and is set to a high level when the tracking servo is drawn in the groove area, as shown in FIG. It Therefore, the output signal S19 of the ExOR gate 31 becomes as shown in FIG.

The OR gate 32 obtains the logical sum of the output signal S19 of the ExOR gate 31 and the servo on / off instruction signal S20 from the controller 16 and uses this as the servo on / off execution signal S21. Output. The servo on / off instruction signal S20 is set to a low level when the tracking servo is turned on, and set to a high level when the tracking servo is turned off, as shown in FIG. To be done. Therefore, the execution signal S21 for servo on / off from the OR gate 32 is as shown in FIG.

The switch 10 for turning on / off the servo is
It is controlled by this execution signal S21. As a result, even if the optical disk 1 is eccentric, the servo can be automatically pulled into the track of the desired pit area or groove area in accordance with the area designation signal S18 from the controller 16. Therefore, even if the optical disc 1 is eccentric, the pit information or the groove recording information near the boundary between the pit area and the groove area can be read.

The optical disk recording / reproducing apparatus according to the invention of claim 1 irradiates the optical beam 1 having the pit area and the groove area with the light beam 50, and records and reproduces information while tracking based on the tracking error signal S1. In the optical disk recording / reproducing apparatus for performing, the light beam 50
The area determination signal S3 indicating whether the pit area or the groove area is irradiated with the tracking error signal S
An area discriminating circuit for outputting based on the level 1 is provided.

According to this, it is possible to determine whether the light beam 50 is applied to the pit area or the groove area. Therefore, the optical pickup 2 is moved from the pit area to the groove area or from the groove area to the pit area. And it will be possible to move quickly and reliably.

The optical disk recording / reproducing apparatus according to the invention of claim 2 irradiates the optical beam 1 having the pit area and the groove area with the light beam 50 to record / reproduce information while tracking based on the tracking error signal S1. In the optical disk recording / reproducing apparatus for performing, the light beam 50
The area discrimination signal S6 or S13 indicating whether the pit area or the groove area is irradiated is output based on the presence or absence of the advance information signal S4 obtained from the groove area or the reproduction signal S11 of the pit information obtained from the pit area. An area discrimination circuit is provided.

According to this, there is an effect similar to that of the optical disk recording / reproducing apparatus according to the first aspect of the present invention.

An optical disk recording / reproducing apparatus according to the invention of claim 3 is the optical disk recording / reproducing apparatus according to claim 1 or 2, wherein the area discrimination signals S3, S
Area discrimination signal S14 corresponding to either S6 or S13
, The groove area determination signal S16 and the pit area determination signal S17 indicating whether the light beam 50 is irradiated to the pit area or the groove area when it is unchanged for at least the time required for the optical disk 1 to rotate once.
A region determination circuit that outputs

According to this, in addition to the effects of the optical disk recording / reproducing apparatus according to the first and second aspects of the present invention, the optical pickup 2 is moved from the pit area to the groove area even when the optical disk 1 is eccentric. Alternatively, it becomes possible to move from the groove area to the pit area quickly and reliably.

An optical disc recording / reproducing apparatus according to the invention of claim 4 is the optical disc recording / reproducing apparatus according to claim 1 or 2, wherein the area discrimination signals S3, S
Control means is provided for turning on / off the servo so that the light beam 50 is tracked to a desired area of either the pit area or the groove area based on the area discrimination signal S14 corresponding to either 6 or S13. .

According to this, in addition to the effects of the optical disk recording / reproducing apparatus according to the inventions of claims 1 and 2, even when the optical disk 1 is eccentric, either the pit area or the groove area is desired. The light beam 50 can be tracked to the area.

[0085]

As described above, the optical disk recording / reproducing apparatus according to the first aspect of the present invention sets the area discrimination signal indicating whether the light beam is irradiated to the pit area or the groove area to the level of the tracking error signal. Since the area discriminating circuit for outputting the light beam is provided, it can be discriminated whether the light beam is applied to the pit area or the groove area. As a result, it is possible to move the optical pickup from the pit area to the groove area or from the groove area to the pit area quickly and reliably.

As described above, the optical disk recording / reproducing apparatus according to the second aspect of the present invention provides the area discriminating signal indicating whether the light beam is irradiated to the pit area or the groove area with the reproducing signal obtained from the groove area or Since the area discriminating circuit for outputting based on the presence or absence of the reproduction signal obtained from the pit area is provided, the same effect as that of the first aspect can be obtained.

As described above, the optical disk recording / reproducing apparatus according to the invention of claim 3 is the optical disk recording / reproducing apparatus of claim 1 or 2, wherein the area discriminating signal makes at least one rotation of the optical disk. Since the area determination circuit that outputs the area determination signal indicating whether the light beam is applied to the pit area or the groove area when the time required for the change is unchanged is provided, the effects of claims 1 and 2 are obtained. In addition, even when the optical disc is eccentric, it is possible to move the optical pickup from the pit area to the groove area or from the groove area to the pit area quickly and reliably.

As described above, the optical disk recording / reproducing apparatus according to the invention of claim 4 is the optical disk recording / reproducing apparatus of claim 1 or 2, wherein the pit area or the groove area is based on the area discrimination signal. 2. A control means for turning on / off the servo is provided so as to track the light beam to any desired area of the above.
In addition to the effects of No. 2 and No. 2, even if the optical disk is eccentric, the light beam can be tracked to a desired area of either the pit area or the groove area.

[Brief description of drawings]

FIG. 1 shows a first embodiment of the present invention and is a block diagram showing a schematic configuration of an optical disc recording / reproducing apparatus.

FIG. 2 is a waveform diagram showing an operation of an area discrimination circuit of the optical disc recording / reproducing apparatus of FIG.

FIG. 3 shows a second embodiment of the present invention and is a block diagram showing an area discriminating circuit of an optical disc recording / reproducing apparatus.

FIG. 4 is a waveform diagram showing the operation of the area discrimination circuit of FIG.

FIG. 5 is an explanatory diagram showing a relationship between a tracking error signal and a prior information signal.

FIG. 6 shows a third embodiment of the present invention and is a block diagram showing an area discriminating circuit of an optical disc recording / reproducing apparatus.

7 is a waveform chart showing the operation of the area discrimination circuit of FIG.

FIG. 8 shows a fourth embodiment of the present invention and is a block diagram showing an area determining circuit of an optical disc recording / reproducing apparatus.

9 is a waveform diagram showing an operation of the area determination circuit of FIG.

FIG. 10 shows a fifth embodiment of the present invention and is a block diagram showing a control means for automatic pull-in of tracking servo of an optical disk recording / reproducing apparatus.

11 is a waveform chart showing the operation of the control means of FIG.

FIG. 12 is a block diagram showing a conventional example and showing a schematic configuration of an optical disc recording / reproducing apparatus.

13 is an explanatory diagram showing the relationship between the tracking error signal and the reproduction signal of pit information obtained by the optical disk recording / reproducing apparatus in FIG.

[Explanation of symbols]

1 Optical Disc 2 Optical Pickup 3 Tracking Error Signal Generation Circuit 4 Pre-Recorded Information Detection Circuit 5 Reproduction Signal Operation Circuit 9 Switch 10 Switch (Control Means) 16 Controller 17 Reference Voltage Source (Area Discrimination Circuit) 18 Comparator (Area Discrimination Circuit) 19 Retriggerable one-shot circuit (region discrimination circuit) 20 Envelope detection circuit (region discrimination circuit) 21 Reference voltage source (region discrimination circuit) 22 Comparator (region discrimination circuit) 26 Envelope detection circuit (region discrimination circuit) 27 Reference voltage Source (area discrimination circuit) 28 Comparator (area discrimination circuit) 29 Retriggerable one-shot circuit (area determination circuit) 30 AND gate (area determination circuit) 31 ExOR gate (control means) 32 OR gate (control means) 33 ExOR gate (Area decision circuit) 51 pits 52 grooves

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuo Nakata 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Within Sharp Corporation (72) Nobuo Ogata 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Within the corporation

Claims (4)

[Claims] 1. An optical disk recording / reproducing apparatus for irradiating an optical disk having a pit area and a groove area with a light beam to record and reproduce information while tracking based on a tracking error signal, wherein the light beam is a pit area or a groove area. An optical disc recording / reproducing apparatus characterized in that an area discriminating circuit for outputting an area discriminating signal indicating which of the two is irradiated based on the level of a tracking error signal is provided. 2. An optical disk recording / reproducing apparatus for irradiating an optical disk having a pit area and a groove area with a light beam, and recording and reproducing information while tracking based on a tracking error signal, wherein the light beam is a pit area or a groove area. A region discriminating circuit is provided which outputs a region discriminating signal indicating which of the two is illuminated based on the presence or absence of a pre-information signal obtained from the groove region or a reproduction signal of pit information obtained from the pit region. Optical disk recording / reproducing device. 3. When the area discrimination signal is unchanged for at least the time required for the optical disk to make one rotation, an area determination signal indicating whether the light beam is applied to the pit area or the groove area is output. The area determining circuit is provided, and the area determining circuit is provided.
The optical disk recording / reproducing apparatus described. 4. A control means for turning on / off a servo is provided so as to track a light beam to a desired area of either a pit area or a groove area based on the area discrimination signal. The optical disc recording / reproducing apparatus according to claim 1.