JPH0935410A - Optical disk drive - Google Patents

Abstract

(57) [Summary] [Purpose] A high-speed and constant data transfer rate can be obtained.
(EN) Provided is an optical disc device which has a short access time, a small device shape, and a low cost, and which is suitable for optical image quality moving image recording / reproduction. [Structure] An outer optical head beam spot 2 along the outer laser beam guide groove 1-1 of the optical disc 1
1 and recording is performed simultaneously with the inner circumference side optical head beam spot 3 along the inner circumference side laser beam guide groove 1-2.
Recording is performed by -1. In addition, the position control of the two optical heads is performed in conjunction with each other, and the recording is performed simultaneously by the MCAV system so that the sum of the data transfer rates of the two optical heads is always constant regardless of the optical disk radial position of the optical heads. Record and play.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high data transfer rate optical disk device used for recording and reproducing moving images.

[0002]

2. Description of the Related Art Conventionally, in a rewritable optical disk device, a CAV (Constant Angular) is used for recording / reproducing at a constant optical disk rotation speed and at a constant data transfer rate regardless of the position of the optical head.
Velocity) method or MCAV (Modified Co) in which the rotation speed of the optical disk is fixed and the data transfer rate is changed according to the position of the optical head.
The nstant Angular Velocity method is used.

Further, in a reproduction-only optical disk reproducing apparatus, a CLV (Con
The stan linear velocity method is used.

Further, one optical head is provided for each side of the optical disk except for special applications such as those for broadcasting stations.

9 (a) and 9 (b) show the basic structure of the optical head / optical disk combination of a conventional recording / reproducing optical disk device.
Recording is performed along the 0-shaped spiral laser beam guide groove 31, and the direction of spiral rotation is the same from the outermost circumference to the innermost circumference. The optical disc 30 is constructed by forming a laser beam guide groove 31 on a base 32, and forming a recording layer 33 and a protective layer 34 on the laser beam guide groove 31. 35 is an objective lens and 36 is a laser beam.

Further, FIG. 10 shows an optical head transfer diameter system of a special optical disk device in which two optical heads 32 are provided on the same surface of the optical disk 30. The two optical heads 32 have different optical optics. The head transfer systems (carriage A, B) 32A, 32B are provided.

[0007]

However, in the above-mentioned conventional MCAV system, the recording linear density becomes lower and the total recording capacity of the optical disc 30 becomes smaller toward the outer peripheral side of the optical disc 30. In the MCAV system, it depends on the position of the optical head. In the MCLV method, in which the data transfer rate changes, the rotation speed of the optical disk changes depending on the position of the optical head. Therefore, when the optical head 32 accesses a distant track, it takes time to change the rotation speed to make the linear velocity constant. Therefore, there is a problem that the optical head access time is delayed.
Further, when the number of the optical head 32 is one, there is a problem that the data transfer rate is low.

Further, in the case of spirally recording on the optical disc 30, the spiral rotation direction of the recording track is the same from the outermost circumference to the innermost circumference, so that from the outer circumference side to the middle circumference side (or from the middle circumference side) on the same plane. The problem that an optical head for recording / reproducing while moving to the outer circumference side and an optical head for recording / reproducing while moving from the inner circumference side to the middle circumference side (or from the middle circumference side to the inner circumference side) cannot be used in combination was there.

Further, in the optical disk device in which the two optical heads 32 are provided on the same surface of the optical disk 30, two optical heads cannot be combined to perform high-speed and constant data transfer rate recording / reproduction. Since 32 is provided in each of the optical head transfer systems 32A and 32B, there is a problem that the shape of the device becomes large and the cost of the device becomes high.

The present invention has been made in view of the above problems, and it is an object of the present invention to obtain a high speed and constant data transfer rate, a short access time, a small device shape, and a low cost. An object of the present invention is to provide an optical disk device which is inexpensive and suitable for optical image quality moving image recording / reproduction and the like.

[0011]

In order to achieve the above object, the optical disk device according to the invention of claim 1 is provided with a spiral laser beam guide groove, and a laser beam from the outermost circumference to the middle circumference on the same plane. An optical disk in which the spiral rotation direction of the guide groove and the spiral rotation direction of the laser beam guide groove from the innermost circumference to the middle circumference are the same, and from the outer circumference side to the middle circumference side (or from the middle circumference side) in the radial direction of the optical disk. An outer circumference side optical head for recording or reproducing while moving to the outer circumference side, and an inner circumference side optical head for recording or reproducing while moving from the inner circumference side to the middle circumference side (or the middle circumference side to the inner circumference side). Tracking servo means for tracking the beam spots of the outer optical head and the inner optical head along the laser beam guide groove, and the outer optical head And moving means for moving the inner circumference side optical head in conjunction with each other, rotation means for rotating the optical disc at a constant rotation speed, and recording data divided into the outer circumference side optical head and the inner circumference side optical head. Recording and reproduction are performed by the MCAV system using a head, and the sum of data transfer rates of the outer optical head and the inner optical head is always constant regardless of the position of the optical head. It is characterized by having a recording / reproducing signal processing means.

In order to achieve the above object, in the optical disk device according to the invention of claim 2, wobble pits for sample servo are spirally arranged, and the wobble pits are arranged from the outermost circumference to the middle circumference on the same surface. The spiral rotation direction of
An optical disk in which the spiral rotation direction of the wobble pit array from the innermost circumference to the middle circumference is the same, and the outer circumference side to the middle circumference side (or the middle circumference side to the outer circumference side) in the radial direction of the optical disk.
An outer circumference side optical head that performs recording or reproduction while moving to, and an inner circumference side optical head that performs recording or reproduction while moving from the inner circumference side to the middle circumference side (or the middle circumference side to the inner circumference side),
Tracking servo means for tracking the beam spots of the outer peripheral side optical head and the inner peripheral side optical head by using the signal of the wobble pit, and the outer peripheral side optical head and the inner peripheral side optical head are moved in association with each other. Moving means, rotating means for rotating the optical disk at a constant rotation speed, recording data is divided, and recording / reproducing is performed by the MCAV method using the outer peripheral side optical head and the inner peripheral side optical head, respectively. ,
The recording / reproducing signal processing means is arranged so that the sum of the data transfer rates of the outer peripheral side optical head and the inner peripheral side optical head is always constant regardless of the position of the optical head. .

In order to achieve the above object, in the optical disc device according to the invention of claim 3, the information pids are arranged in a spiral shape, and the spiral rotation direction of the information pid arrangement is from the outermost circumference to the middle circumference of the same plane. And an optical disc in which information is pit-recorded by the MCAV system or MCLV system with the same spiral rotation direction of the information pit array from the innermost circumference to the middle circumference, and the outer circumference side to the middle circumference side (or the radial direction of the optical disk). An outer circumference side optical head that performs reproduction while moving from the middle circumference side to the outer circumference side, and an inner circumference side optical head that performs reproduction while moving from the inner circumference side to the middle circumference side (or from the middle circumference side to the inner circumference side). Tracking servo means for tracking the beam spots of the outer peripheral side optical head and the inner peripheral side optical head to the information pits, the outer peripheral side optical head and the inner peripheral side optical The sum of the moving means for moving the head in conjunction with each other, the rotating means for rotating the optical disk at a constant rotation speed, and the reproduction data transfer rate of the outer peripheral side optical head and the inner peripheral side optical head is the optical head. It has a reproduction signal processing means that is always constant regardless of the position.

In order to achieve the above object, in the optical disc device according to the invention of claim 4, the spiral rotation direction of the information pid array is from the outermost circumference of the upper recording surface (or the lower recording surface) to the innermost circumference. A multilayer recording optical disc in which information is pit-recorded by the MCAV system or MCLV system with the same spiral rotation direction of the information pit array from the innermost circumference to the outermost circumference of the lower recording surface (or the upper recording surface); An upper layer optical head for reproducing the upper layer recording surface while moving from the outer peripheral side to the inner peripheral side (or the inner peripheral side to the outer peripheral side) in the radial direction, and the inner peripheral side to the outer peripheral side (or the outer peripheral side to the inner peripheral side). Moving to the lower layer recording surface to reproduce the lower layer recording surface, and the beam spot of the upper layer optical head to the information pit of the upper layer recording surface to the beam spot of the lower layer optical head. Servo means for respectively tracking the optical disk on the information layer of the lower recording surface, moving means for moving the upper optical head and the lower optical head in conjunction with each other, and rotating means for rotating the optical disc at a constant rotational speed. And a reproduction signal processing means for keeping the sum of the reproduction data transfer rates of the upper layer optical head and the lower layer optical head constant irrespective of the position of the optical head.

In order to achieve the above object, the optical disk device according to the invention of claim 5 is the optical disk device according to claim 1 or claim 2 or claim 3 or claim 4 in the diameter direction of the optical disk. An optical head that performs recording or reproduction while moving from the outer circumference side to the middle circumference side (or from the inner circumference side to the outer circumference side) and recording while moving from the inner circumference side to the middle circumference side (or the middle circumference side to the inner circumference side) Alternatively, it is characterized by a structure in which an optical head for reproducing is provided on one carriage.

[0016]

According to the optical disk device of the present invention, two optical heads (outer peripheral side,
Inner side optical heads are arranged so that each optical head follows the laser beam guide groove of the optical disk, and the outer side optical head moves from the outer side to the middle side (or from the middle side to the outer side) in the radial direction of the optical disk. When moving to the side), the inner circumference side optical head can be moved from the inner circumference side to the middle circumference side (or the middle circumference side or the inner circumference side) in conjunction with the outer circumference side optical head.

Rotating means for rotating the optical disc at a constant rotational speed, recording / reproducing with respect to the outer peripheral side optical head and the inner peripheral side optical head by the MCAV system, and the outer peripheral side optical head and the outer peripheral side optical head, respectively. Since the sum of the data transfer rates of the inner-circumferential-side optical head is provided with a recording / reproducing signal processing means that is always constant regardless of the position of the optical head, a high-speed and constant data transfer is achieved. Recording and reproduction can be performed. Moreover, since the optical disk is rotated at a constant rotation speed, the access time can be shortened.

According to the optical disk device of the second aspect of the present invention, two optical heads (outer peripheral side and inner peripheral side optical heads) are arranged on the same surface of the optical disk, and each optical head is a spiral of the optical disk. While following the wobble pits arranged like a circle, when the outer optical head moves from the outer circumference to the middle circumference (or the middle circumference or the outer circumference) in the radial direction of the optical disc, the outer circumference optical head interlocks with this outer circumference optical head. It is possible to move the inner circumference side optical head from the inner circumference side to the middle circumference side (or the middle circumference side or the inner circumference side). Rotating means for rotating the optical disc at a constant rotation speed, recording / reproducing by the MCAV system for the outer peripheral side optical head and the inner peripheral side optical head, respectively, and for the outer peripheral side optical head and the inner peripheral side. Since the sum of the data transfer rates of the side optical heads is provided with a recording / reproducing signal processing means that is always constant regardless of the position of the optical head, high-speed recording and reproducing at a constant data transfer rate are performed. be able to. Moreover, since the optical disk is rotated at a constant rotation speed, the access time can be shortened.

According to the optical disk device of the third aspect of the present invention, two optical heads (outer peripheral side optical head and inner peripheral side optical head) are arranged on the same surface of the optical disk, and each optical head is an optical disk. When the outer optical head moves from the outer peripheral side to the middle peripheral side (or the middle peripheral side or the outer peripheral side) in the radial direction of the optical disk while following the spirally arranged information pits, it is interlocked with this outer peripheral side optical head. The inner circumference side optical head from the inner circumference side to the middle circumference side (or the middle circumference side or the inner circumference side)
Can be moved to.

Further, the information pids are arranged in a spiral shape, and the spiral rotation direction of the information pid array extending from the outermost circumference to the middle circumference of the same plane and the spiral rotation direction of the information pit arrangement extending from the innermost circumference to the middle circumference are defined. Similarly, the sum of an optical disc on which information is pit-recorded by the MCAV system or the MCLV system, a rotating means for rotating the optical disc at a constant rotation speed, and a reproduction data transfer rate of the outer peripheral side optical head and the inner peripheral side optical head. However, since it has the reproduction signal processing means which is always constant regardless of the position of the optical head, it is possible to perform reproduction at a high speed and a constant data transfer rate. Moreover, since the optical disk is rotated at a constant rotation speed, the access time can be shortened.

According to the optical disk device of the present invention, two optical heads (upper layer and lower layer optical head) are arranged on the same surface of the optical disk, and each optical head is recorded on the upper layer recording surface of the optical disk. When the upper layer optical head moves from the outer peripheral side to the inner peripheral side (or the inner peripheral side or the outer peripheral side) in the radial direction of the optical disk while following the spirally arranged information pits on the lower recording surface and the upper layer, The lower layer optical head can be moved from the inner peripheral side to the outer peripheral side (or the outer peripheral side or the inner peripheral side) in conjunction with the optical head.

In addition, the spiral rotation direction of the information pid array from the outermost circumference of the upper recording surface (or the lower recording surface) to the innermost circumference and the innermost circumference of the lower recording surface (or the upper recording surface) toward the outermost circumference. A multilayer recording optical disc in which information is pit-recorded by the MCAV system or the MCLV system with the spiral rotation direction of the information pit array being the same, rotating means for rotating the optical disc at a constant rotation speed, the upper optical head and the lower optical head. The sum of the playback data transfer rates of
Since the reproduction signal processing means is arranged so as to be always constant regardless of the position of the optical head, it is possible to perform reproduction at a high speed and a constant data transfer rate.
Moreover, since the optical disk is rotated at a constant rotation speed, the access time can be shortened.

According to the optical disk device of the fifth aspect, one optical head is provided on one carriage, and when the carriage is moved in the diameter direction of the optical disk, one optical head is on the outer peripheral side. To the middle circumference side (or the middle circumference side to the outer circumference side), and the other optical head is arranged in such a positional relationship that it moves from the inner circumference side to the middle circumference side (or the middle circumference side to the inner circumference side). Therefore, with one drive mechanism system, when one optical head moves from the outer circumference side to the middle circumference side (or from the middle circumference side to the outer circumference side) in the radial direction of the optical disc, at the same time, the other head moves inward. It is possible to move in conjunction with each other from the circumference side to the middle circumference side (or the middle circumference side or the inner circumference side).

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical disk device of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is an explanatory view showing the basic structure of an optical head / optical disk combination of an optical disk device according to Embodiment 1 of the present invention, and FIG. 2 is a recording using the MCAV method using two optical heads. FIG. 3 is an explanatory diagram showing a schematic operation of a recording / reproducing signal processing means for always keeping the sum of data transfer rates of two optical heads constant.

In FIG. 1, 1 is an optical disk, 1-1 is an outer peripheral side laser beam guide groove provided in the optical disk 1, and 1-2 is an inner peripheral side laser which is a spiral rotating laser beam guide groove provided in the optical disk 1. Beam guide groove, 2
Reference numeral -1 is a beam spot of the outer optical head, and 3-1 is a beam spot of the inner optical head. The outer circumference side laser beam guide groove 1-1 is provided in a spiral shape in which the spiral rotation direction from the outermost circumference of the optical disk 1 toward the middle circumference is counterclockwise, and the inner circumference side groove 1-2 is the innermost side of the optical disk 1. The spiral rotation direction from the circumference toward the middle circumference is also provided in the counterclockwise spiral shape. In other words, paying attention only to the direction of spiral rotation and defining the direction of spiral rotation as the direction from the outer circumference to the inner circumference, the spiral laser beam guide groove is formed from the outermost circumference to the middle circumference of the optical disc 1. Counterclockwise, it is provided clockwise from the middle circumference to the innermost circumference.
Further, in FIG. 2, 2 is an outer peripheral side optical head, 3 is an inner peripheral side optical head, and 4 is a recording / reproducing signal processing means.

Next, referring also to FIG. 1 and FIG.
The operation of the optical disc device according to the first embodiment will be described.

In FIG. 1, the optical disk 1 rotates at a constant rotational speed, and the beam spot 2 of the outer optical head 2 is rotated.
MCAV recording is performed while -1 moves (illustrated) from the outer circumference side to the middle circumference side in the radial direction of the optical disc 1 along the outer circumference side laser beam guide groove 1-1. Similarly,
The beam spot 3-1 of the inner optical head 3 is guided along the inner laser beam guide groove 1-2 so that the optical disk 1
Recording of the MCAV system is performed while moving from the inner circumference side to the middle circumference side in the radial direction (shown).

In the MCAV system, when the rotation speed of the optical disc 1 is constant, the linear velocity becomes faster toward the outer peripheral side of the optical disc 1. Therefore, by increasing the recording data transfer rate almost in proportion to the linear velocity, the optical disc This is a method used for a high-capacity hard optical disk device, an optical disk device, or the like used in an external storage device such as a computer, which is capable of increasing the recording capacity of No. 1.

By the tracking servo means,
When the laser beam spots 2-1 and 3-1 are about to come off from the inner circumference side laser beam guide grooves 1-1 and 1-2, they are detected and controlled so as not to come off. As the tracking servo means, there are a push-pull method and a beam method which are generally used.

The outer circumference side optical head 2 and the inner circumference side optical head 3 are moved to the outer circumference side by the tracking servo means.
While following the inner circumference side laser beam guide grooves 1-1 and 1-2, and when the outer circumference side optical head 2 moves to the inner circumference side by the moving means, the inner circumference side optical head 3 interlocks with the outer circumference side. To move. As the moving means, any one of a linear motor, a stepping motor and a DC motor is used as a drive source,
It is composed of a transfer system mechanism that moves a carriage equipped with an optical head along a linear guide and a control circuit that controls a drive motor. Normally, the transfer system mechanism is provided separately for the outer peripheral side optical head and the inner peripheral side optical head, and both optical heads are moved in conjunction with each other by a control circuit. There is also a way to make one.

Next, the operation of the recording / reproducing signal processing means when the data transfer rate is constant at 24 Mbps will be described with reference to FIG. In FIG. 2, at the time of recording, 24
Recording signals of Mbps are recorded at 16 Mbps, 15 Mbps, and 14 Mbps corresponding to the radial position of the outer optical head 2.
5 stages of s, 13 Mbps, and 12 Mbps, and 8 Mbps and 9 Mbps corresponding to the radial position of the inner circumference side optical head 3.
s, 10 Mbps, 11 Mbps, and 12 Mbps are divided into five data transfer rates in each combination and recorded on the optical disc 1. At the time of reproduction, the track positional relationship between the outer optical head 2 and the inner optical head 3 is reproduced at the same time as recording, and the reproduction signals of the respective optical heads 2 and 3 are combined to reproduce at a constant 24 Mbps. You are getting a signal. By the way, in the conventional 1-optical-head MCAV system, the data transfer rate changes in the range of 8 Mbps to 16 Mbps depending on the track position of the optical head, so that it is limited to 8 Mbps when recording moving images in real time. In this embodiment, 24 Mbps is constant, and high-quality moving image recording / reproduction can be performed.

According to the first embodiment described above, the optical disc 1
Spiral-shaped outer and inner laser beam guide grooves 1-
1 and 1-2 are provided, recording / reproduction is performed by the tracking servo means while causing the beam spots 2-1 and 3-1 to follow the outer and inner circumference side laser beam guide grooves 1-1 and 1-2. And the spiral rotation direction of the laser beam guide groove 1-1 on the outer peripheral side from the outermost circumference to the middle circumference,
Inner circumference side laser beam guide groove 1 going from the innermost circumference to the middle circumference
-2 is the same as the spiral rotation direction, so that two optics (the head outer peripheral side and the inner peripheral side optical heads 2 and 3) are arranged on the same surface of the optical disc 1, and one optical head 2 is the outer peripheral side. When recording / reproducing while moving from the inner side to the middle side, it is possible to record / reproduce while moving the other optical head 3 from the inner side to the middle side. Since the recording is performed on the optical disc 1 by the MCAV method using the head 3, the total recording capacity per optical disc 1 can be increased, and when the outer optical head 2 moves to the inner peripheral side, the inner peripheral can be linked with this. Since the side optical head 3 is recording and reproducing by the MCAV system while moving to the middle circumference side, the sum of the data transfer rates of both optical heads 2 and 3 is always constant by using the recording / reproducing signal processing means. To be Since the two optical heads 2 and 3 are used for recording and reproducing at the same time, the data transfer rate can be increased, and the optical head access time can be shortened because the rotation speed of the optical disk 1 is constant. .

In Example 1 shown in FIGS. 1 and 2, recording is performed while the outer peripheral optical head 2 moves from the outer peripheral side to the middle peripheral side, and the inner peripheral side optical head 3 moves from the inner peripheral side to the middle peripheral side. Although the case of reproducing is shown, the same effect can be obtained when recording and reproducing while the outer optical head 2 moves from the middle side to the outer side and the inner optical head 3 moves from the middle side to the inner side. be able to.

The above-mentioned first embodiment is the optical disc 1
At the time of recording, the outermost circumference to the middle circumference and the innermost circumference to the middle circumference are separately recorded into five data zones corresponding to five stages of data transfer rates. If the number of divided zones is increased by making the switching stage finer, the recording capacity also increases, but the circuit system becomes complicated, and conversely, if the number of divided zones is reduced, the capacity decreases but the circuit system becomes simpler. The number of divided zones may be determined according to the goal.

(Second Embodiment) Next, a second embodiment of the optical disk device of the present invention will be described.

3A and 3B are explanatory views showing the basic structure of the optical head / optical disk combination of the optical disk device of Embodiment 2, where FIG. 3A is an overall view of the optical disk surface, and FIG. 3B is a partially enlarged perspective view of the optical disk. FIG. 4 is an explanatory diagram showing a schematic operation of a general sample servo system using wobble pits.

In FIG. 3, 6 is a wobble pit, which is a spiral outer track center S of the optical disk 5.
No. 1 and the spiral inner track center S2 are arranged at regular intervals. The wobble pits 6 are a pair of pits provided on both sides of the outer circumference side and the inner circumference side track centers S1 and S2 with the positions in the track direction being slightly shifted.
Made at the time of base molding. The rest of the configuration is the same as that of the above-described first embodiment, where 7 is the beam spot of the outer optical head 2 and 8 is the beam spot of the inner optical head 3.

Next, the operation of the optical disk device according to the second embodiment will be described with reference to FIGS.

In FIG. 3, the optical disk 5 rotates at a constant rotation speed, and the beam spot 7 of the outer optical head 2 is rotated.
While moving along the outer circumference side track center S1 from the outer circumference side in the radial direction of the optical disk 5 to the middle circumference side, MC
AV recording is performed. Similarly, the beam spot 8 of the inner-side optical head 3 moves along the inner-side track center S2 from the inner side to the middle side in the radial direction of the optical disc 5 to perform MCAV recording.

Further, in FIG. 4, the beam spots 7, along the outer and inner track centers S1, S2,
8 moves relative to the optical disc 5, A1 ・ B
1, A2, B2, ... Detection signals are obtained, and the beam spots 7 and 8 are located on the outer circumference side and inner circumference side track centers S.
1 and S2 deviate from each other, the peak values of the detection signal A and the detection signal B are different from each other. Therefore, this difference is used as a tracking error signal, and the outer and inner track centers S1 and S2
The deviation from is controlled to fall within the allowable range.
In the area where there is no wobble pit 6, the tracking error signal is obtained by holding the signal by the sample hold circuit. Generally, such a tracking servo system is called a sample servo system, and a data recording area is provided between each wobble pit 6. Other operations are the same as those in the first embodiment described above.

Further, according to the second embodiment described above, the spiral outer circumference side and inner circumference side track centers S are formed on the optical disk 5.
Since wobble pits 6 are arrayed at regular intervals along S1 and S2, recording / reproduction is performed by the tracking servo means of the sample servo system while causing the beam spot 6 to follow the outer and inner track centers S1 and S2. Since the spiral rotation direction of the wobble pits 6 array from the outermost circumference to the middle circumference is the same as the spiral rotation direction of the wobble pits 6 array from the innermost circumference to the middle circumference, Two optical heads (outer peripheral side and inner peripheral side optical heads 2 and 3) are arranged on the same surface, and when one optical head 2 moves from the outer peripheral side to the middle peripheral side for recording and reproduction, the other optical head is used. Recording and reproduction can be performed while moving the head 3 from the inner circumference side to the middle circumference side, and the optical disk 5 is formed by using the outer circumference side optical head 2 and the inner circumference side optical head 3.
Since the recording is performed by the MCAV system, the recording capacity of the optical disk can be increased, and when the outer peripheral optical head 2 moves to the middle circumference side, the outer peripheral optical head 2 moves to the middle circumference side in conjunction with this. Since recording and reproduction are performed by the MCAV system, respectively, the sum of the data transfer rates of both optical heads 2 and 3 can always be made constant by using the recording / reproducing signal processing means. Since data is simultaneously recorded / reproduced by using 3, the data transfer rate can be increased and the optical head access time can be shortened because the rotation speed of the optical disk 5 is constant.

In the second embodiment shown in FIG. 3, recording / reproduction is performed while the outer peripheral optical head 2 moves from the outer peripheral side to the middle peripheral side and the inner peripheral side optical head 3 moves from the inner peripheral side to the middle peripheral side. However, similar effects can be obtained when recording / reproducing is performed while the outer peripheral optical head 2 moves from the inner peripheral side to the outer peripheral side and the inner peripheral optical head 3 moves from the middle peripheral side to the inner peripheral side. .

(Third Embodiment) Next, a third embodiment of the optical disk device of the present invention will be described.

5A and 5B are explanatory views showing the basic structure of the optical head / optical disk combination of the optical disk device of the third embodiment, wherein FIG. 5A is an overall view of the optical disk surface, and FIG. 5B is a partially enlarged perspective view of the optical disk. is there.

In FIG. 5, reference numeral 10 denotes outer peripheral side information pids, and these outer peripheral side information pids 10 are spirally arranged on the outer peripheral side of the optical disc 9. Reference numeral 11 denotes an inner circumference side information pid, and these inner circumference side information pids 11 are spirally arranged on the inner circumference side of the optical disc 9. And 12
Is a beam spot of the outer optical head 2 and 13 is a beam spot of the inner optical head 3. The other configurations are similar to those of the above-described first embodiment.

Next, the operation of the optical disk device according to the third embodiment will be described with reference to FIG. In FIG. 5, the optical disc 9 is rotated at a constant rotation speed, and the beam spots 12 of the outer optical head 2 are spirally arranged along the outer peripheral information pid 10 from the outer peripheral side in the radial direction of the optical disc 9. Play while moving to the lap side.
Similarly, the beam spot 13 of the inner optical head 3 is reproduced while moving from the outer peripheral side in the radial direction of the optical disk 9 to the middle peripheral side along the inner peripheral information pits 11 arranged in a spiral shape.

The reproduction-only optical disc is a replica optical disc made by resin molding or the like using a stamper recorded by the MCAV system or the MCLV system, and when the same one is mass-produced, it can be inexpensive. The MCLV system is a system in which the data transfer rate is fixed and the rotational speed is changed stepwise according to the radius of the optical disc for recording. However, the recorded optical disc-like data format is MCAV.
It is similar to the method. As the tracking servo means for tracking along the outer peripheral side and inner peripheral side information pit rows, as in the first embodiment, there are a three-beam method and a push-pull method which are generally used.

The outer and inner circumference information pits 10 and 11 are
Pre-pit recording is performed by dividing the data transfer rate into the same data transfer rate as in recording in Example 1 shown in FIG.
The same as when playing. Other operations are similar to those of the first embodiment.

According to the third embodiment described above, the optical disc 9
Since the outer and inner circumference information pits 10 and 11 are arranged in a spiral shape, the beam spots 11 and 12 are formed by the tracking servo means of the three-beam method or the push-pull method.
Can be reproduced while following the outer peripheral side and inner peripheral side information pits 10 and 11, and the spiral rotation direction of the outer peripheral side information pit 10 array from the outermost peripheral side to the middle peripheral side, and from the innermost peripheral side to the middle peripheral side. Since the spiral rotation direction of the arrangement of the inner peripheral side information pits 11 is the same, two optical heads (outer peripheral side, inner peripheral side optical heads 2 and 3) are arranged on the same surface of the optical disc 9, and the outer peripheral side is arranged. When reproducing while the optical head 2 moves from the outer circumference side to the middle circumference side, it is possible to perform the reproduction while moving the inner side optical head 3 from the inner circumference side to the middle circumference side, and the optical disk 9 uses the MCAV system or MCLV. Since the information is pre-pit recorded by the method, the recording capacity of the optical disc can be increased, and when the outer peripheral optical head 2 moves to the inner peripheral side, the inner peripheral optical head 3 is moved to the inner peripheral side in conjunction with this. While moving to Each MCAV scheme or MCL
Since the optical disc 9 recorded by the V method is reproduced, the sum of the reproduction data transfer rates of both the optical heads 2 and 3 can always be made constant by using the reproduction signal processing means. Since data is reproduced simultaneously using the heads 2 and 3, the data transfer rate can be increased, and the optical head access time can be shortened because the rotation speed of the optical disk 9 is constant.

Although the outer peripheral side and inner peripheral side information pits 10 and 11 are concave in the third embodiment shown in FIG. 5, they may be convex. Also, the outer and inner information pits 10,
11 includes data pits, address mark pits, clock pits and the like required by the user.

(Fourth Embodiment) Next, a fourth embodiment of the optical disk device of the present invention will be described. FIG. 6 is an explanatory diagram showing a schematic configuration of a read-only multi-layer recording optical disc apparatus of Example 4,
7A and 7B are explanatory views showing the information pit array, where FIG. 7A shows the upper layer recording surface of the optical disc, and FIG. 7B shows the lower layer recording surface of the optical disc.

The optical disc 14 has an upper layer information pit 15
And a lower layer information pit 16 is provided. And
The upper layer information pits 15 are arranged in a counterclockwise spiral shape from the outermost circumference to the innermost circumference of the optical disc 14,
The lower layer information pits 16 are arranged in a counterclockwise spiral shape from the innermost circumference to the outermost circumference of the optical disc 14.
Further, 17 is an upper layer side optical head, 17-1 is a beam spot of the upper layer side information pit 15, 18 is an upper layer side optical head,
Reference numeral 18-1 is a beam spot of the lower layer information pit 16.

Next, with reference to FIGS. 6 and 7, the operation of the optical disk device according to the fourth embodiment will be described.

In FIG. 6, the beam spot 17-1 of the upper layer side optical head 17 is focused on the upper layer information pit 15 and the beam spot 18-1 of the lower layer side optical head 18 is focused on the lower layer information pit 16, respectively. Play. The laser beam of the lower layer optical head 17 first hits the upper layer information pit 15, and the transmitted light is focused on the beam spot diameter to hit the lower layer information pit 16. However, the beam diameter of the portion hitting the upper layer information pit 15 is the size of the information pit. Since it is larger than the above, the influence of noise due to the upper layer information pit 15 can be almost ignored.

Further, in FIG. 7, the optical disc 14 rotates at a constant rotational speed, and the beam spot 17-1 of the upper layer side optical head 17 is arranged along the upper layer information pit 15 in which the beam spot 17-1 is spirally arranged. Playback is performed while moving from the outer circumference side to the inner circumference side in the radial direction. Similarly, the beam spot 18-1 of the lower layer side optical head 18 is reproduced while moving from the inner radius side to the outer radius side of the optical disc 14 along the lower layer information pits 16 arranged spirally.

The reproduction-only multi-layer recording optical disk is MCAV.
System or MCLV system, and is made by stacking optical discs made by resin molding, chemical treatment or the like by laminating. As the tracking servo means for performing tracking along the information pid row, as in the first and third embodiments, there are generally used three-beam method, push-pull method, and the like.

The upper and lower information pits 15 and 16 are shown in FIG.
The pre-pit recording is performed on the upper recording surface and the lower recording surface of the optical disc 14 by dividing the data transfer rate similar to that at the time of recording in the first embodiment shown in FIG.
7 and the lower layer side optical head 18 are used in the same manner as in the reproducing operation of the first embodiment shown in FIG. Other operations are similar to those of the first embodiment.

As described above, according to the fourth embodiment,
Since the upper layer and lower layer information pits 15 and 16 are spirally arranged on the optical disc 14, the beam spots 17-1 and 18-1 are formed into the upper layer and lower layer information pits 15 by the tracking servo means of the three-beam system or the push-pull system. , 16
It is possible to perform reproduction while following the above, and the spiral rotation direction of the upper layer information pit 15 array extending from the outermost circumference to the middle circumference of the upper layer recording surface and the lower layer information pit 16 extending from the innermost circumference to the outermost circumference of the lower layer recording surface. Since the spiral rotation direction of the array is the same, two optical heads (upper layer and lower layer optical heads 17 and 18) are arranged on the same surface side of the optical disc 14, and one optical head 17 is moved from the outer peripheral side to the inner side. When reproducing while moving to the circumference side, it is possible to reproduce while moving the other optical head 18 from the inner circumference side to the outer circumference side, and since the optical disk 14 is prepit recorded by the MCAV system or the MCLV system, The optical disc recording capacity can be increased, and when the upper layer side optical head 17 moves to the inner circumference side, the lower layer side optical head 18 moves to the outer circumference side in conjunction with this, Respectively MCAV scheme or MCLV
Since the optical disc 14 recorded by the method is reproduced, the reproduction signal processing means is used to
The sum of the reproduction data transfer rates of 18 can be made constant at all times, and since the reproduction is simultaneously performed by using the two optical heads 17 and 18, the data transfer rate can be increased, and the rotation speed of the optical disk 14 can be increased. Is constant, the optical head access time can be shortened.

In the fourth embodiment shown in FIG. 6, the upper and lower layer information pits 15 and 16 have a convex shape, but may have a concave shape. Although the fourth embodiment is a read-only optical disc having a two-layer structure, it can be applied to a multi-layer structure having four layers and six layers.

(Fifth Embodiment) Next, a fifth embodiment of the optical disk device of the present invention will be described. FIG. 8 is an explanatory diagram showing the configuration of an optical head transfer system used in the optical disk device of the fifth embodiment.

In FIG. 8, the outer peripheral optical head 20 and the inner peripheral optical head 21 are attached to the carriage 19. The carriage 19 is held in a slidable state along the guide shafts 22a and 22b fixed in parallel. The outer peripheral optical head 20
And the inner optical head 21 is the optical disc D.
A beam spot (2) of the outer optical head 2 is formed with a straight line parallel to the guide shafts 22a and 22b passing through the center of (1, 5, 9, 14) with the center of the optical disc D interposed therebetween.
-1, 7, 12, 17-1) is on the outermost track T1 of the optical disc D, the beam spot (3-1, 8, 13, 18-1) of the inner optical head 3 is the innermost track. It is attached in such a positional relationship as on the track T2.
24 is a lead screw, which is a stepping motor 2
It is directly connected to the rotation center axis of 3. A screw pin 25 is fixed to the carriage 19 along the groove of the lead screw 24.

Next, with reference to FIG. 8 as well, the operation of the optical disk device according to the fifth embodiment will be described.

In FIG. 8, when the lead screw 24 rotates in the direction of the arrow by the step rotation driving force of the stepping motor 23, the lead screw pin 25 moves along the groove of the lead screw 24, and the lead screw pin 25 moves. Carriage 1 to which 25 is fixed
9 moves in the direction of the arrow along the guide shafts 22a and 22b. Since the outer peripheral side optical head 20 and the inner peripheral side optical head 21 are attached to one carriage 19, both optical heads 20 and 21 move in conjunction with the movement of the carriage 19.

An objective lens (not shown) is provided in each of the outer peripheral optical head 20 and the inner peripheral head 21.
In order to carry out tracking and focusing by finely driving the position of, the actuator includes an actuator composed of a coil, a magnet, a suspension mechanism, etc., and tracking and focusing are performed separately for each side optical head.

According to the fifth embodiment described above, the outer peripheral side optical head 20 and the inner peripheral side optical head 21 are attached to one carriage 19, and both optical heads 20 and 21 pass through the center of the optical disc D. 22a, 22b
When the beam spot of the outer optical head 20 is on the outermost track T1 of the optical disc D with the center of the optical disc D sandwiched between them on a straight line parallel to, the beam spot of the inner optical head 21 is the innermost track. Since it is attached in a positional relationship such as on T2, one carriage 1
By moving 9, the inner circumference side optical head 20 can move in conjunction with the outer circumference side when the outer circumference side optical head 20 moves toward the inner circumference side.

The fifth embodiment shown in FIG. 8 is the carriage 1
Although the stepping motor 23 is used as the drive motor of No. 9, it can be similarly driven by using the DC motor or the linear motor.

[0068]

As described above, according to the optical disk device of the first aspect of the present invention, the spiral rotation direction of the laser beam guide groove from the outermost circumference to the middle circumference of the same surface of the optical disk, and from the innermost circumference. An optical disk having the same spiral rotation direction of the laser beam guide groove toward the middle circumference, an outer circumference side optical head, an inner circumference side optical head, and beam spots of the outer circumference side optical head and the inner circumference side optical head Since the tracking servo means for tracking along the laser beam guide groove and the moving means for moving the outer peripheral side optical head and the inner peripheral side optical head in conjunction with each other are provided, it is possible to arrange them on the same surface of the optical disc.
The optical heads (outer peripheral side and inner peripheral side) are arranged so that each optical head follows the laser beam guide groove of the optical disk, and the outer optical head moves from the outer peripheral side to the middle peripheral in the radial direction of the optical disk. When moving from side to side (or from the inner circumference side to the outer circumference side), move the inner circumference side optical head from the inner circumference side to the middle circumference side (or the middle circumference side or the inner circumference side) in conjunction with this side optical head. You can

Rotation means for rotating the optical disc at a constant rotation speed, recording / reproducing for the outer peripheral side optical head and the inner peripheral side optical head by the MCAV system, and the outer peripheral side optical head and the outer peripheral side optical head are performed. Since the sum of the data transfer rates of the inner-circumferential-side optical head has a recording / reproducing signal processing unit that is always constant regardless of the position of the optical head, high-speed recording with a constant data transfer rate is performed. Playback can be performed.

Further, since the optical disk is rotated at a constant rotation speed, the access time can be shortened.

According to the optical disk device of the second aspect of the present invention, wobble pits for sample servo are spirally arranged, and the spiral rotation direction of the wobble pit arrangement is from the outermost circumference to the middle circumference of the same plane. Optical disk having the same spiral rotation direction of the wobble pit array from the innermost circumference to the middle circumference, an outer circumference side optical head, an inner circumference side optical head, the outer circumference side optical head and the inner circumference side optical head beam A tracking servo means for causing a spot to follow a spiral data track of an optical disk by using a signal by the wobble pit, and a moving means for moving the outer peripheral side optical head and the inner peripheral side optical head in association with each other are provided. As a result, 2 on the same side of the optical disk
While arranging a number of optical heads (outer circumference side and inner circumference side optical heads) and allowing each optical head to follow the wobble pits arranged in a spiral on the optical disk, the outer circumference side optical head is positioned on the outer circumference side in the radial direction of the optical disk. From the inner circumference side to the middle circumference side (or the middle circumference side or the outer circumference side), the inner circumference side optical head is moved from the inner circumference side to the middle circumference side (or the middle circumference side or the inner circumference side) in conjunction with the outer circumference side optical head. Can be moved to.

Rotating means for rotating the optical disc at a constant rotation speed, recording / reproducing on / from the outer peripheral side optical head and the inner peripheral side optical head by the MCAV system, and the outer peripheral side optical head and the outer peripheral side optical head are performed. Since the sum of the data transfer rates of the inner-circumferential-side optical head is always constant regardless of the position of the optical head, the recording / reproducing signal processing means is provided, so that high-speed and constant data transfer rate recording is performed. Playback can be performed.

Further, since the optical disk is rotated at a constant rotation speed, the access time can be shortened.

According to the optical disk device of the third aspect of the present invention, the information pits are arranged in a spiral shape, and the spiral rotation direction of the information pit arrangement is from the outermost circumference to the middle circumference of the same plane, and from the innermost circumference. An optical disk recorded with the same spiral rotation direction of the information pit array toward the middle circumference, an outer circumference side optical head, an inner circumference side optical head, and a beam spot of the outer circumference side optical head and the inner circumference side optical head. Since it has a tracking servo means for following the information pits arranged in a spiral and a moving means for moving the outer peripheral side optical head and the inner peripheral side optical head in conjunction with each other, the same surface of the optical disk is provided. Two optical heads (outer peripheral side and inner peripheral side optical heads) are arranged in the optical disk so that each optical head follows the information pits spirally arranged on the optical disk. , Middle center periphery optical head from the outer circumferential side in the radial direction of the optical disk (or circumferential side or outer circumferential side inside)
When moving to, the inner circumference side optical head can be moved from the inner circumference side to the middle circumference side (or the middle circumference side or the inner circumference side) in conjunction with the outer circumference side optical head.

Further, the information pits are arranged in a spiral form, and the spiral rotation direction of the information pit array extending from the outermost circumference to the middle circumference and the spiral rotation direction of the information pit arrangement extending from the innermost circumference to the middle circumference are defined. Similarly, the sum of an optical disc on which information is pit-recorded by the MCAV system or the MCLV system, a rotating means for rotating the optical disc at a constant rotation speed, and a reproduction data transfer rate of the outer peripheral side optical head and the inner peripheral side optical head. However, since the reproduction signal processing means is arranged so as to be always constant regardless of the position of the side optical head, it is possible to perform reproduction at a high speed and a constant data transfer rate.

Since the optical disk is rotated at a constant rotation speed, the access time can be shortened.

According to the optical disk device of the fourth aspect of the present invention, the spiral rotation direction of the information pit array from the outermost circumference of the upper recording surface (or the lower recording surface) to the inner circumference,
The spiral rotation direction of the information pit array extending from the innermost circumference to the outermost circumference of the lower recording surface (or the upper recording surface) is the same as M
A multilayer recording optical disc in which information is pit-recorded by the CAV method or the MCLV method, an upper layer side optical head, a lower layer side optical head, and a beam spot of the upper layer side optical head in an information pit on the upper layer recording surface and the lower layer side optical head. Since there are tracking servo means for tracking the beam spot of the head to the information pits of the lower layer recording surface, and moving means for moving the upper layer side optical head and the lower layer side optical head in conjunction with each other, Two optical heads (upper layer side and lower layer side optical heads) are arranged on the same side of the optical disc, and each of the optical heads is respectively placed in spirally arranged information pits on the upper layer recording surface and the lower layer recording surface of the optical disc. While following, the upper layer side optical head moves from the outer circumference side to the inner circumference side (or the inner circumference side in the radial direction of the optical disk). When moving to the circumferential side), it is possible to this movement in conjunction with the upper side optical head from the inner side of the lower side optical head toward the outer periphery (or the outer circumferential side or the inner circumferential side).

The spiral rotation direction of the information pit array from the outermost circumference of the upper recording surface (or the lower recording surface) to the innermost circumference and the innermost circumference of the lower recording surface (or the upper recording surface) toward the outermost circumference. A multi-layer recording optical disc in which information is pit-recorded by the MCAV system or MCLV system with the spiral rotation direction of the information pit array being the same, rotating means for rotating the optical disc at a constant rotation speed, the upper layer side optical head and the lower layer. Since the reproduction signal processing means is arranged so that the sum of the reproduction data transfer rates of the side optical heads is always constant regardless of the position of the optical head, high-speed and constant data transfer rate reproduction is performed. You can

Further, since the optical disk is rotated at a constant rotation speed, the access time can be shortened.

According to the optical disk device of the fifth aspect of the invention, in the optical disk device of the first aspect, the second aspect, the third aspect or the fourth aspect, two side optical heads are provided for one carriage. When the carriage is moved in the diametrical direction of the optical disc, one side optical head moves from the outer circumference side to the middle circumference side (or the middle circumference side to the outer circumference side), and the other side optical head moves from the inner circumference side. The optical disk device according to claim 1 or claim 2 or claim 3 or claim 4 described above, because the optical disk device is arranged in such a positional relationship that it moves from the middle circumference side (or from the middle circumference side to the inner circumference side). Not only can similar effects be obtained, but when one side optical head moves from the outer circumference side to the middle circumference side (or from the middle circumference side to the outer circumference side) in the radial direction of the optical disk with one drive mechanism system, the other simultaneously The inner head It can be moved in conjunction with each other in the circumferential side medium (or medium circumferential side or the inner circumferential side) from.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a basic configuration of an optical head / optical disk combination of an optical disk device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a schematic operation of a recording / reproducing signal processing means in the optical disc device.

FIG. 3 is an explanatory diagram showing a basic configuration of an optical head / optical disc combination of an optical disc device according to a second embodiment of the present invention, in which (a) is an overall view of an optical disc surface and (b) is an enlarged perspective view of an optical disc portion.

FIG. 4 is an explanatory diagram showing a schematic operation of a sample servo system using a general wobble pit in the optical disc device.

FIG. 5 is an explanatory diagram showing a basic configuration of an optical head / optical disk combination of a read-only optical disk device in Embodiment 3 of the present invention, in which (a) is an overall view of an optical disk surface and (b) is an enlarged view of an optical disk portion. Perspective view

FIG. 6 is an explanatory diagram showing a schematic configuration of a read-only multilayer recording optical disk device according to a fourth embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a read-only multi-layer recording optical disk information pit array in the read-only multi-layer recording optical disk device, wherein (a) is an upper layer recording surface of the optical disk and (b) is a lower layer recording surface of the optical disk.

FIG. 8 is an explanatory diagram showing a configuration of an optical head transfer system according to a fifth embodiment of the present invention.

FIG. 9 is an explanatory view showing a basic configuration of a combination of an optical head and an optical disk of an optical disk device in a conventional technique, (a) is an overall view of an optical disk surface, and (b) is an enlarged view of an optical disk portion.

FIG. 10 is an explanatory diagram showing a schematic configuration of a side optical head transfer system of an optical disc device using two optical heads per one side of an optical disc in a conventional technique.

[Explanation of symbols]

 1, 5, 9, 14, 30 Optical disc 1-1 Outer peripheral side laser beam guide groove 1-2 Inner peripheral side laser beam guide groove 2, 20 Outer peripheral side optical head 2-1, 7, 12 Outer peripheral side optical head beam spot 3, 21 inner circumference side optical head 3-1, 8, 13 inner circumference side optical head beam spot 4 recording / reproducing signal processing 6 wobble pit 10 outer circumference side information pit 11 inner circumference side information pit 14-1 upper layer optical disk 14-2 lower layer optical disk 15 Upper layer information pit 16 Lower layer information pit 17 Upper layer side optical head 17-1 Upper layer side optical head beam spot 18 Lower layer side optical head 18-1 Lower layer side optical head beam spot 19 Carriage 22a, 22b Guide shaft 23 Stepping motor 24 Lead screw 25 Screw Pin 31 Laser beam guide groove 3 The optical head beam spot

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G11B 25/04 101 G11B 25/04 101B

Claims (5)

[Claims] 1. A spiral laser beam guide groove is provided,
An optical disc in which the spiral rotation direction of the laser beam guide groove from the outermost circumference to the middle circumference on the same plane is the same as the spiral rotation direction of the laser beam guide groove from the innermost circumference to the middle circumference, and in the radial direction of the optical disk. While moving from the outer circumference side to the middle circumference side (or from the middle circumference side to the outer circumference side), the outer circumference side optical head that performs recording or reproduction, and while moving from the inner circumference side to the middle circumference side (or from the middle side to the inner circumference side) An inner circumference side optical head for recording or reproducing, a tracking servo means for tracking the beam spots of the outer circumference side optical head and the inner circumference side optical head along the laser beam guide groove, the outer circumference side optical head and the above Moving means for moving the inner optical head in conjunction with each other, rotating means for rotating the optical disk at a constant rotation speed, and recording data division. Then, recording and reproducing are performed by the YCAV method using the outer peripheral side optical head and the inner peripheral side optical head, respectively, and the sum of the data transfer rates of the outer peripheral side optical head and the inner peripheral side optical head is An optical disc device comprising: a recording / reproducing signal processing means which is always constant regardless of the position of the head. 2. A wobble pit for sample servo is spirally arranged, and a spiral rotation direction of a wobble pit arrangement from the outermost circumference to the middle circumference of the same surface and a spiral of wobble pit arrangement from the innermost circumference to the middle circumference. From an inner circumference side, an optical disk having the same rotation direction, an outer circumference side optical head for recording or reproducing while moving from the outer circumference side to the middle circumference side (or from the middle circumference side to the outer circumference side) in the radial direction of the optical disk. A signal generated by the wobble pit is used to record the beam spot of the inner circumference side optical head for recording or reproducing while moving from the middle circumference side (or the middle circumference side to the inner circumference side), and the outer circumference side optical head and the inner circumference side optical head. Tracking servo means for tracking using the optical disk, moving means for moving the outer peripheral side optical head and the inner peripheral side optical head in conjunction with each other, and the optical disc. By rotating the rotating means for rotating the recording medium at a constant rotation speed and the recording data by dividing the recording data by using the outer peripheral side optical head and the inner peripheral side optical head.
The sum of the data transfer rates of recording / reproducing in the AV system and of the outer peripheral side optical head and the inner peripheral side optical head is
An optical disk device comprising: a recording / reproducing signal processing means which is always constant regardless of the position of the optical head. 3. The information pids are arranged in a spiral shape, and the spiral rotation direction of the information pid array extending from the outermost circumference to the middle circumference of the same plane and the spiral rotation direction of the information pit arrangement extending from the innermost circumference to the middle circumference are defined. Similarly, an optical disc in which information is pit-recorded by the MCAV system or the MCLV system, and an outer peripheral side optical head for reproducing while moving from the outer peripheral side to the middle peripheral side (or the middle peripheral side to the outer peripheral side) in the radial direction of the optical disc. , The inner circumference side optical head for reproducing while moving from the inner circumference side to the middle circumference side (or the middle circumference side to the inner circumference side), and the beam spots of the outer circumference side optical head and the inner circumference side optical head Tracking servo means for tracking to pits, moving means for moving the outer peripheral side optical head and the inner peripheral side optical head in conjunction with each other, and a constant rotation speed of the optical disk. And a reproduction signal processing means for making the sum of reproduction data transfer rates of the outer peripheral side optical head and the inner peripheral side optical head always constant regardless of the position of the optical head. An optical optical disk device characterized by: 4. The spiral rotation direction of the information pid array from the outermost circumference of the upper recording surface (or the lower recording surface) to the innermost circumference, and from the innermost circumference of the lower recording surface (or the upper recording surface) to the outermost circumference. A multilayer recording optical disc in which information is pit-recorded by the MCAV system or MCLV system with the spiral rotation direction of the information pit array being the same, and from the outer circumference side to the middle circumference side (or from the inner circumference side to the outer circumference side) in the radial direction of the optical disk. An upper layer optical head for reproducing the upper layer recording surface while moving, a lower layer optical head for reproducing the lower layer recording surface while moving from the inner peripheral side to the outer peripheral side (or the outer peripheral side to the inner peripheral side), and the upper layer Tracking for tracking the beam spot of the optical head to the information pit of the upper recording surface and the beam spot of the lower optical head to the information pid of the lower recording surface Servo means, moving means for moving the upper layer optical head and the lower layer optical head in conjunction with each other, rotating means for rotating the optical disc at a constant rotation speed, and reproduction data of the upper layer optical head and the lower layer optical head. An optical disk device, comprising: a reproduction signal processing unit that keeps the sum of transfer rates constant regardless of the position of the optical head. 5. An optical head for recording or reproducing while moving from the outer circumference side to the middle circumference side (or the middle circumference side to the outer circumference side) in the diametrical direction of the optical disk, and the inner circumference side to the middle circumference side (or the middle circumference side). 5. The optical disk device according to claim 1, wherein the optical head for recording or reproducing while moving from the inner side to the inner peripheral side) is provided in one carriage. .