JP2733398B2 - Optical disk drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention records information on both sides.
The present invention relates to an optical disk device that performs recording and reproduction using an optical disk to be recorded .

[0002]

2. Description of the Related Art Reproduction of a conventional optical disk and optical disk apparatus will be described.

First, when viewed from the reproducing (recording) side of the optical disc 1, as shown in FIG. 6, information arranged in a pit row is recorded in a clockwise spiral from inside to outside. .

The optical disk 1 is mounted on a turntable and rotates in the direction of arrow A, that is, in the counterclockwise direction. Information on the optical disk 1 is reproduced by an optical head (not shown) movable in the radial direction of the disk. This is performed by scanning the pit row 2 with a light spot.

[0005] From the pit row 2 of the optical disk 1 and the rotation direction of the arrow A, information is reproduced while the optical head movable in the radial direction moves from the inside to the outside.

There is a double-sided optical disk on which an optical disk 1 having an information pit array 2 formed on one surface is bonded, and the arrangement of the information pit array is the same in both directions.

To reproduce information on the double-sided optical disk, as shown in FIG. 7, the first side 3a of the double-sided optical disk 3 to be reproduced is set on the turntable 5 with the optical head 4 facing the optical head 4, and the spindle motor 6 drives the arrow. By rotating the optical head 4 in the direction indicated by A and moving the optical head 4 from the inner circumference to the outer circumference in the radial direction, information is read from the optical head 4. When the information recorded on the first surface 3a of the double-sided optical disk 3 has been reproduced to the outer periphery and the information recorded on the opposite second surface 3b is to be reproduced continuously, the rotation of the spindle motor 6 is temporarily stopped. And the double-sided optical disk 3
Is taken out from the turntable 5, turned over, and set on the turntable 5 again. Then, in the same manner as the reproduction of information on the first surface 3a of the double-sided optical disc 3, the optical head 4
, The information on the second surface 3b is read from the inner periphery toward the outer periphery.

As described above, when reproducing the information on both sides 3a and 3b by manually reversing the double-sided optical disk 3, it takes time and effort to reverse the double-sided optical disk 3, and the spindle motor is required to reverse the double-sided optical disk 3. The time required for stopping the double-sided optical disk 3, the time required for taking out and reversing the double-sided optical disk 3 and setting it on the turntable 5, the time required for starting the spindle motor 6 again and stabilizing the rotation, etc. are required.

In particular, when playing software such as a movie or a live stage on an optical video disc or the like , the first
The time and effort required to make the transition from the surface to the second surface are as follows:
It is not preferable because the flow of the story and the live stage is disrupted and wakes up.

In order to shorten the transition time from the first surface 3a to the second surface 3b, a double-sided continuous reproducing apparatus has been proposed. FIG. 5 is a conceptual diagram showing an example of a continuous reproduction apparatus for a double-sided optical disk, and a schematic procedure for reproducing recorded information will be described below.

In FIG. 5, information recorded on the first surface 3a of the double-sided optical disk 3 is reproduced in the same manner as described above. After the reproduction of the first surface 3a is completed, the optical head 4
a along the guide rail 7 formed in a U-shape over the second surface 3b from the optical head 4 to the second surface 3b.
a, 4-b, and 4-c, and moves to 4-d, which is the innermost position of the second surface 3b.

The optical head 4 moves from the first surface 3a to the second surface 3a.
While moving to b, the spindle motor 6 reverses the rotation. This is, as described above, the first side 3a of the double-sided optical disc,
A series of information pits are recorded in a clockwise direction from the inner circumference to the outer circumference on both the second surface 3b. Since the information is reproduced along the information pit sequence, the reproduction of the second surface 3b is the reverse of the reproduction of the first surface 3a. Direction disk rotation is required.

[0013]

With such a double-sided continuous playback apparatus for a double-sided optical disk as described above, when the playback surface is switched, the double-sided optical disk is once manually taken out of the apparatus, the double-sided optical disk is turned over, and set in the apparatus again. Time is no longer needed.

However, (i) a start-up time until the spindle motor 6 for rotating the double-sided optical disc 3 in reverse is rotated stably, and (ii) the optical head 4 is moved from the outer periphery of the first side 3a of the double-sided optical disc 3 to the second side. It takes time to move the inner circumference of 3b.

In a normal device, the above items (i) and (ii) are performed in parallel, so that the time required for both operations is not added.
The time required for reversing the optical disk is longer,
It takes ten and several seconds from the end of the reproduction of the first surface 3a to the start of the reproduction of the second surface 3b.

As described above, the conventional optical disk and optical disk apparatus have a drawback that it takes a long time to switch the recording / reproducing surface.

[0017]

In order to solve the above-mentioned drawback, the invention according to claim 1 provides information on a first surface and a second surface.
Driving means for rotatingly driving the recorded optical disc;
The first surface of the optical disk rotated by the moving means
Or, irradiate a light spot on the information track on the second surface, and
The optical head that receives the return light of the
Moving the optical head to follow the
And a first step of moving the optical head by the moving means.
By selectively positioning them on the surface side and the second surface side,
An optical disk for recording or reproducing information with one optical head
In the disk drive, the optical disk has the first surface
Clockwise or counterclockwise from the inner circumference to the outermost circumference
Information is recorded on the second surface and the outermost
Information is recorded counterclockwise or clockwise toward
While the optical disk is used,
Rotate the optical disk counterclockwise or clockwise.
In addition, the light spot is moved
When the optical head is moved to follow the
Whether the optical head moves inward or outward
The above optical disc is set correctly based on
Discriminating means for discriminating whether or not the light
If it is determined that the disc is not set correctly
Moving the optical head by the moving means,
And control means for positioning it on the other side .

According to a second aspect of the present invention, the first surface and the second surface are provided.
For rotating an optical disk having information recorded thereon
And the optical disk rotationally driven by the driving unit
A light spot on the information track on the first or second surface of the
An optical head that emits light and receives the return light
Move the optical head so that it follows the information track
Moving means, and the light head is moved by the moving means.
To selectively position the gate on the first side and the second side.
Record or reproduce information with a single optical head.
In the optical disk device, the optical disk
Clockwise or counterclockwise on one surface from innermost to outermost
The information is recorded clockwise and the outermost
Information from counterclockwise or clockwise toward the innermost circumference
While the optical disk on which the
Therefore, rotate the optical disk counterclockwise or clockwise.
While rotating, the light spot will be
Move the optical head so that it follows the information track
When the information reproduced by the optical head is correct
Whether the above optical disc is set correctly
Determining means for determining whether or not
It is determined that the above optical disc is not set correctly
The rotation direction of the optical disk by the driving means
And control means for inverting .

[0019]

According to the first aspect of the present invention, the first surface is provided.
Clockwise or counterclockwise from the innermost circumference to the outermost circumference
Information is recorded in the direction
Information is written counterclockwise or clockwise toward the outer circumference.
By using the optical disc to be recorded, it is not necessary to reverse the rotation of the driving means when the recording or reproducing surface is switched, and the time for switching the surface can be reduced by moving the optical head from the outer periphery of the first surface to the inner periphery of the second surface. one of the time only to move to parts
On the other hand, the optical disk is turned counterclockwise or
Rotate it clockwise and move the light
Move the optical head so that the unit follows the information track.
The optical head moves inward or outward.
The discriminating means determines whether the optical disc is correctly
Is determined whether or not the optical
When it is determined that the disk is not set correctly,
The control means moves the optical head by the moving means,
The optical disc so that it is set correctly.
The optical disc correctly when it is not loaded
Recording or playback without re-writing
You.

According to the second aspect of the present invention, the first surface is
Clockwise or counterclockwise from the inner circumference to the outermost circumference
Information is recorded on the second surface and the outermost
Recording of countercurrent bought by counterclockwise or information clockwise
Recording or playback by using an optical disc
It is necessary to reverse the rotation of the driving means when the surface to be switched is switched
Movement of the optical head and the outer peripheral portion of the first surface.
To the outer periphery of the second surface, so the waiting time for surface switching
Is greatly reduced, while the drive means
Turn counterclockwise or clockwise and move
The light spot follows the information track by moving means
When the optical head is moved,
Based on whether correct information is reproduced or not,
Determine whether the disc is set correctly, and
Optical disc is not set correctly
When it is determined that the optical data is
By reversing the disk rotation direction,
If the optical disc is not set correctly,
Perform recording or playback without re-setting correctly
be able to.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical disk and an optical disk apparatus according to the present invention will be described with reference to the drawings.

In the optical disc of the present invention, the recording start point and recording direction of information are as shown in FIGS. 1 and 2, for example. In FIG. 1, the first surface 8a of the double-sided optical disk 8 is shown.
In the second surface 8b, information is recorded from the inner periphery to the outer periphery in a counterclockwise direction starting from the inner periphery.

In FIG. 2, information is recorded on the first surface 9a of the double-sided disk 9 in a clockwise direction starting from the inner periphery toward the outer periphery, and the second surface 9b is formed on the inner periphery in a counterclockwise direction starting from the outer periphery. Information is being recorded. The above information recording direction is when the respective surfaces of the double-sided optical disks 8 and 9 are viewed from the optical head, and the rotation direction of the double-sided optical disk 9 is as shown by an arrow B in FIG.

Next, a case where the optical disk 8 is driven by an optical disk device will be described with reference to FIG. Normally, for example, the double-sided optical disk 8 shown in FIG. 1 is placed on the turntable 5 with the first surface 8a facing downward, that is, facing the turntable 5, and the double-sided optical disk 8 is viewed from the optical head by the spindle motor 6. and rotation in the clockwise direction, as a result, information of the first surface 8a is detected by the optical head 4 toward the outer periphery from the inner periphery is reproduced.

During this reproduction operation, the double-sided optical disk 8
The case where the second surface 8b is set downward is described below. In this case, the optical head 4 reads information in a clockwise direction from the outer periphery toward the inner periphery, even though information is recorded in the second surface 8b starting from the inner periphery toward the outer periphery in a counterclockwise direction. As a matter of course, the information is not correctly reproduced.

An example of a method for detecting such an erroneous double-sided optical disk setting will be described with reference to FIG. 3. In order to accurately irradiate a light spot on an information track, the optical head 4 controls the objective lens 10 to carry out information processing. It has an actuator 11 that is driven in a direction perpendicular to the tracks in the pit row. Of course, the actuator 11 has a structure that can be driven in the direction of the rotation axis of the double-sided optical disk 8 but is omitted here. In addition, the light spot irradiated from the optical head 4 is moved to the first surface 8a or the second surface 8b of the double-sided optical disk 8.
What track error signal indicating whether the upper track are correctly follow (TES) is output from the optical head 4. The track error signal TES is applied to the actuator 11 via a servo circuit 15 including an amplifier 12, a phase compensation circuit 13, an actuator drive circuit 14, and the like, and servo is applied so that the light spot always follows the track. .

On the other hand, the movement of the optical head 4 is detected by a DC offset detection circuit 16 which detects a DC offset generated on the servo signal, and a head feed circuit 18 which always keeps the DC offset at zero or below a certain level. This is performed by a feed mechanism (not shown). Reference numeral 17 denotes a polarity determination circuit.

Assuming that information on the first surface 8a or the second surface 8b of the double-sided optical disk 8 is recorded from the inner circumference to the outer circumference, FIG. It will be described based on the following. FIG. 4A shows a state in which the objective lens 10 is not shifted with respect to the double-sided optical disk 8, and the track error signal TES has a waviness caused by the eccentricity of the disk with respect to the time axis (t) around zero. ing. Since information is recorded from the inner circumference to the outer circumference of the double-sided optical disk 8, the objective lens 10 gradually shifts toward the outer circumference as shown in FIG. 4 (b). At this time, the waveform of the track error signal TES has a DC offset.

The polarity of the DC offset caused by the shift of the objective lens 10 depends on the shift direction of the objective lens 10. In FIG. 4B, the objective lens 10 shifts to the outer peripheral side, and as a result, the track error signal TES has a positive DC offset.
When 0 shifts in the inner circumferential direction, a negative DC offset occurs. Therefore, DC in the track error signal TES
The direction of movement of the objective lens 10 can be determined based on the polarity of the offset.

As shown in FIG. 4B, when a DC offset occurs in the track error signal TES, the optical disk device sends the optical head 4 to the outer circumference so that the DC offset becomes zero. That is, as shown in FIG. 4A to FIG. 4C, the operation of the apparatus is such that the objective lens shift → DC
The procedure is as follows: offset generation → optical head feed → objective lens shift is eliminated.

[0031] Therefore, if the setting of the double-sided optical disc 8 is correct, when the inner periphery objective lens 10 and the optical head 4 is moved to the periphery, also is incorrect setting of the double-sided optical disk 8 passes through the objective lens 10 and the optical Since the head 4 moves in the inner circumferential direction, the TES caused by the lens shift
From the DC offset or the polarity of the optical head drive signal ,
It can be determined whether or not the setting of the surface optical disk 8 is correct . And, when the setting error is detected,
While maintaining the rotation of the double-sided optical disk 8, the optical head 4
Is moved to the opposite side, and the normal reproduction operation is performed if the reproduction is performed from the inner circumference.

On the other hand, when the double-sided optical disk 9 is used,
There are a first surface 9a even when set to the optical disk apparatus by mistake and a second surface 9b, of course it becomes a reverse play, information reproduction is not done properly. In this case, the moving direction of the objective lens
Since it cannot be determined whether or not the double-sided optical disc 9 is set correctly, a software determination is performed. That is, an error caused by improper reading of information is detected as a disc setting error. More specifically, when reading the so-called index of a disk, which is called a lead-in area, during the first reproduction of a disk, if the reproduction direction is wrong, the reading becomes impossible. Determines that reproduction is impossible, and stops the reproduction operation. Then, the right to <br/> return to play in this case, to move the optical head in the opposite side may be inverted to disk rotation.

The information recording direction on the double-sided disk has been described in the embodiment with respect to the disk in which the first surface is recorded in a clockwise spiral shape. However, the present invention is not limited to this. That is, even if the first surface is counterclockwise, the recording / reproducing of information is exactly the same as long as the rotation direction of the spindle motor of the optical disk device is clockwise and the information recording direction of the second surface is the corresponding direction. is Ru done.

[0034]

As it is evident from the foregoing description, according to the first aspect of the invention, without switching the rotation direction of the optical disc in the first and second surfaces of the optical disc, to read reproducing information from an optical disc Surface switching can be performed in a short time, and the optical disc can be set in the correct direction.
The optical disc correctly even if it is not
Recording or playback can be performed without rewriting
Therefore, when setting the optical disc,
There is no need to worry about the orientation,
Can be up.

According to the second aspect of the present invention, an optical disk
The direction of rotation of the optical disk between the first and second surfaces
Read and reproduce information from optical discs without
And the reproduction of the second surface from the first surface
When this is done, the travel distance will be shorter,
Surface switching can be performed in a shorter time, and
Even if the lock is not set in the correct orientation,
Without having to reload the optical disk correctly,
Can perform playback.
You do not have to worry about the orientation of the optical disc when
Therefore, the usability of the user can be improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an example of an optical disk used in an optical disk device of the present invention.

FIG. 2 is an explanatory diagram showing another example of the optical disk used in the optical disk device of the present invention.

FIG. 3 is a block diagram of the optical disk device of the present invention.

FIGS. 4A, 4B, and 4C show the relationship between a track error signal (TES) and a DC offset due to a shift of an optical head in a state where an optical spot follows a track on a disk. It is operation | movement explanatory drawing.

FIG. 5 is a schematic configuration diagram of a guide rail of an optical head implemented in the optical disc device of the present invention.

6 is an explanatory view of a conventional optical disk.

FIG. 7 is a schematic configuration diagram of a conventional optical disk device.

[Explanation of symbols]

 3, 8, 9 Double-sided optical disk 4 Optical head 7 Guide rail of optical head 11 Actuator 15 Servo circuit 16 DC offset detection circuit 17 Polarity discrimination circuit 18 Head feed circuit

Claims (2)

(57) [Claims] 1. A light on which information is recorded on a first surface and a second surface.
Drive means for driving the disk to rotate, and the drive means
Of the first surface or the second surface of the optical disc which is rotationally driven
Irradiate a light spot on the information track and receive the return light
Light head and light spot follow the information track
Moving means for moving the optical head so as to move the optical head to the first surface and the second surface by the moving means.
Single optical head by selective positioning on the surface side
Optical disk device that records or reproduces information
And the optical disc is directed from the innermost circumference to the outermost circumference on the first surface.
Information is recorded clockwise or counterclockwise
Also, on the second surface, counterclockwise from the innermost circumference to the outermost circumference
Use an optical disk on which information is recorded clockwise or clockwise
On the other hand, the optical disk is rotated counterclockwise by the driving means.
Or clockwise, and move
Light so that the light spot follows the information track.
When the optical head is moved, the optical head moves inward.
The optical disc is correct based on whether
Discriminating means for discriminating whether or not the optical disc has been correctly set; and
When it is determined that there is no
Control means for moving the optical head and positioning it on the other surface;
An optical disk device characterized by comprising: 2. A light having information recorded on a first surface and a second surface.
Drive means for driving the disk to rotate, and the drive means
Of the first surface or the second surface of the optical disc which is rotationally driven
Irradiate a light spot on the information track and receive the return light
Light head and light spot follow the information track
Moving means for moving the optical head so as to move the optical head to the first surface and the second surface by the moving means.
Single optical head by selective positioning on the surface side
Optical disk device that records or reproduces information
And the optical disc is directed from the innermost circumference to the outermost circumference on the first surface.
Information is recorded clockwise or counterclockwise
Also, on the second surface, counterclockwise from the outermost circumference to the innermost circumference
Use an optical disk on which information is recorded clockwise or clockwise
On the other hand, the optical disk is rotated counterclockwise by the driving means.
Or clockwise, and move
Light so that the light spot follows the information track.
When the optical head is moved,
The optical disc is correct based on whether the information
Discriminating means for discriminating whether or not the optical disc has been set correctly; and
When it is determined that the light is not
Control means for reversing the rotation direction of the disc.
An optical disc device characterized by the following.