KR20110124380A - Apparatus and controlling method for optical disc - Google Patents

Abstract

PURPOSE: An optical disk device and a control method thereof are provided to increase the speed of writing or reading without increasing the disk rotation speed. CONSTITUTION: A first pickup arrives the reading or writing start point of a second pickup. The second pickup directly performs reading or writing rather than the first pickup. An optical disk device moves the first pickup. The first pickup starts reading or writing from the moved position.

Description

Optical disc device and control method {Apparatus and controlling method for optical disc}

The present invention relates to an apparatus and method for speeding up data reading and writing using a plurality of optical pickups.

As an auxiliary storage device for a host computer or server, an optical disk device is required not only for high capacity but also for high speed. Currently, CD / DVD MFPs, which are widely used, have playback speeds and recording speeds of 40 times or more in the CD series and 10 to 10 times in the DVD series. Products at 20x speed are on sale.

Recently, optical disc apparatuses capable of playing or recording BD (Blu-ray Disc) discs have also been released, with products having a maximum playback speed of about 10 times. However, even if a BD disc is played at 10 times speed, it takes about 16 minutes to transfer all the data contained in the disc to the host, and consumers may feel that the time is too long.

The easiest way to think about speeding up the playback or recording speed is to increase the speed of the disc. In order to increase the speed of the disc, the performance of the spindle motor that rotates the disc must be further improved. Also, there are many problems to be solved, such as increasing the output power of the detector, improving the response speed of the photodetector detecting the laser beam, expanding the bandwidth of the actuator's transfer function, and suppressing vibration and noise. Thus, the method of increasing the speed of the disk by increasing the number of revolutions of the disk is almost reaching its limit.

Another method to increase the disk speed is to use multiple beams (or multiple pickup heads). However, in the Seek operation where the limited buffer memory or the optical pickup seeks the next position, the speed is substantially improved due to the settling time of the servo. Not suitable for continuous data reading and writing.

Accordingly, the present invention was created to solve the above problems, and an object of the present invention is to provide a method for substantially improving data recording and reproducing speed by using a plurality of optical pickups.

In accordance with an aspect of the present invention, an optical disk control method includes: checking whether a first pickup reaches a read or write start point of a second pickup that is being read or written in advance of itself; ; Moving the first pick-up to reach a position before the second pick-up or the third pick-up in the read or write progress direction after the first pick-up reaches the starting point as a result of the checking; And restarting reading or writing from the position at which the first pickup is moved.

An optical disk apparatus according to another embodiment of the present invention, a plurality of optical pickup; A recording / reproducing section for driving the optical pickup and processing signals and data; And a control unit for controlling the recording / reproducing unit, wherein the control unit checks whether the first pickup reaches a read or write start point of the second pickup that is being read or written in advance of itself, and confirms the result. After the first pickup reaches the start point, the first pickup is moved to reach a position that is a predetermined length ahead of the second pickup or the third pickup that is the most advanced in the read or write progress direction, and the position where the first pickup is moved. Control to resume reading or writing.

In one embodiment, the position in the circumferential direction at which the first pickup will resume reading or writing may not be fixed, wherein the position in the circumferential direction at which the first pickup resumes reading is moved and the tracking servo is moved. Can be any position after stabilization and the circumferential position at which the first pickup will begin writing again can be the starting point of a given recording unit after the first pickup has moved and the tracking servo has stabilized.

In one embodiment, the plurality of optical pickups comprises a first pickup and a second pickup arranged symmetrically about a disc clamp hole and the first pickup and the second pickup are conveyed by another sled motor or The first pick-up and the second pick-up are arranged at an acute angle around the disc clamp hole, and the first pick-up and the second pick-up may be carried by one sled motor.

In an embodiment, the controller controls the recording / reproducing unit to compare a current position obtained by decoding data read by the first pickup or by detecting address information formed on a disc, with a starting point stored for the second pickup. The first pickup may update and store the position where the first pickup resumes reading or writing.

In an embodiment, the control unit controls the recording / reproducing unit to reduce the power of the laser diode of the first pickup to the reproducing power when the first pickup performing the writing operation reaches the starting point, and then moves the writing operation. When restarting, the power of the laser diode can be adjusted to the recording power.

Thus, it is possible to increase the read or write speed, that is, the transfer speed, without increasing the disk rotation speed.

1 shows a configuration of an optical disc apparatus capable of playing or recording an optical disc such as a CD, DVD, BD,
2 is an operation flowchart of a conventional method of sharing data areas using two optical pickups to simultaneously read or simultaneously write data;
FIG. 3 shows an example in which two optical pickups are disposed at an angle of 180 degrees about a disc clamp hole and the simultaneous reading or writing in a conventional manner while maintaining a distance of 0.5 tracks between the two pickups,
FIG. 4 is a graph showing a movement path of a pickup over time when two pickups perform a data read or write operation by the method of FIGS. 2 and 3;
5 is a representation of a reading speed or a recording speed of data when two pickups perform a data reading or writing operation by the method of FIGS. 2 and 3;
FIG. 6 shows an example in which two optical pickups are disposed at an angle of 180 degrees about the disc clamp hole and the simultaneous reading or writing in the conventional manner while maintaining a distance of 1.5 tracks between the two pickups,
FIG. 7 represents the reading speed or the writing speed of data when two pickups having a 1.5 track interval perform the data reading or writing operation by the method of FIGS. 2 and 6;
8 is a flowchart illustrating an operation of a multiple pickup read or write method according to an embodiment of the present invention;
9 illustrates an embodiment according to the present invention in which two pickups simultaneously perform data reading or reproducing operations with two optical pickups arranged symmetrically about a disk clamp hole.
FIG. 10 is a graph illustrating a movement path of a pickup over time when two pickups perform a data read or write operation according to an embodiment of the present invention.
FIG. 11 illustrates a read speed or a write speed of data when two pickups perform a data read or write operation according to an embodiment of the present invention.
FIG. 12 is a method according to the present invention as shown in FIGS. 8 and 9 to express the read speed or the write speed of data in various track Seek environments when two pickups perform a data read or write operation.
13 and 14 illustrate embodiments according to the present invention that vary the placement and / or number of pickups,
15 is a diagram illustrating a read speed or a write speed of data when data read or write operations are performed with three pickups according to an embodiment of the present invention.
16 and 17 illustrate when data is read from or written to a disc by two pickups according to an embodiment of the present invention, the data read from the two pickups are combined to be transmitted to or transmitted from the host. An example of recording the divided data into two pickups is shown.

Hereinafter, an embodiment of an optical disk device and a control method according to the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 shows the configuration of an optical disc apparatus capable of playing or recording an optical disc such as a CD, DVD, BD.

The optical disk device includes a spindle motor 11, a sled motor 12, and an optical pickup 20 for recording data to or reading data from the optical disk using a laser beam. The spindle motor 11 ), A recording / reproducing unit for driving the sled motor 12 and the optical pickup 20 and processing servo signals and recording / reproducing data, and a control unit 70 for controlling the recording / reproducing system. The recording / reproducing unit may include an optical driver 30, a digital signal processor 40, an R / F unit 50, a servo / drive unit 60, and the like. The optical driver 30 may be included in the optical pickup 20.

The digital signal processor 40 adds an error correction code (ECC) or the like to the digital data to be converted into a recording format, and the optical driver 30 outputs a light quantity driving signal according to the input signal, and the optical pickup 20 records data on the optical disc 10 or reads data from the recording surface of the optical disc 10 in accordance with the light amount driving signal.

The R / F unit 50 filters the signal detected by the optical pickup 20 to output a binary signal by shaping the filter, and also generates and outputs a tracking error signal TE, a focus error signal FE, and an RF signal. In addition, the digital signal processor 40 restores the binary signal to original data using its own clock synchronized with the binary signal, and the servo / drive unit 60 receives the signal from the R / F unit 50. To generate a servo signal for focusing servo, tracking servo, sled servo, and spindle servo, and to drive the spindle motor 11 for rotating the optical disk 10, and the inner and outer circumferential directions of the optical pickup 20. Drive the sled motor 12 to move to the target, and also drive the current required for the focusing servo and tracking servo of the objective lens in the optical pickup 20.

The control unit 70 controls each element to write data to or read data from the optical disc. The optical drive unit 30 controls the optical pickup to read data from the optical disc 10. The laser diode in 20 is driven with reproducing power or the laser diode is driven with recording power for recording data on the optical disc 10.

In addition, the control unit 70 is based on the RF signal detected by the optical pickup 20 and output from the R / F unit 50 and the FG signal generated in the spindle motor 11, the servo / The drive unit 60 is controlled to drive the spindle motor 11 to rotate the disk 10 at a desired speed, and to drive the sled motor 12 to move the optical pickup 20 to a desired position in and out. Current is applied to the actuator supporting the objective lens in the optical pickup 20 so that the laser beam coming out of the objective lens is focused on the desired recording layer (layer jump) and the distance between the objective lens and the disc is reduced. Perform a constant focusing servo, and also perform a tracking servo that moves the laser beam to the desired track (track jump) and causes the laser beam to follow the center of the pit or mark of the disc. The optical disk device may move the laser beam emitted from the objective lens in and out around through the sled motor 12 and the actuator.

An optical disk apparatus using a plurality of optical pickups, for example two optical pickups to increase reproduction or recording speed, can be used in the apparatus of FIG. 1 to independently control Seek, reproduction (or recording). 20 and two optical drivers 30 may be configured, and the R / F unit 50 and the servo / drive unit 60 may be configured as a single module for each optical pickup 20 separately.

In addition, the sled motor 12 may also be configured separately according to the arrangement of the two optical pickups. When the optical pickups are arranged symmetrically (180 degrees) around the disc clamp hole, the optical pickups may be transported. Sled motors must be provided separately for each optical pickup, and if two optical pickups are positioned at angles less than 180 degrees around the clamp holes of the disc, they may share bases with each other, in which case they are transported by one sled motor. May be

FIG. 2 is an operational flowchart of a conventional method of sharing data areas using two optical pickups to simultaneously read or simultaneously write data. As shown in FIG. 3, two optical pickups are arranged symmetrically (180 degrees angle) about the disc clamp hole, and the distance between the two pickups (distance difference in the radial direction) can keep several tracks. Both pickups hold 0.5 tracks.

A second pickup (indicated by a blue circle in FIG. 3), i.e., a second track that reads or writes the outer track in the circumferential direction while the first pickup (indicated by a red circle in FIG. 3) performs a read (or write) operation. Check that the pickup has reached the position (starting point) where it has started the read (or write) operation, and if it has not yet reached, the first and second pickups continue to read (Fig. 3 (a) and (b)). .

When the first pick-up reaches the starting point of the second pick-up (FIG. 3 (c)), the first pick-up and the second pick-up stop the read operation and drive the sled motor or actuator to further track the first periphery through the track jump. The pickup performs a Seek operation to reach a position where the second pickup stops the read operation, and the second pickup also performs a Seek operation to reach the next track which has not yet been recorded ((d) in FIG. 3). When the first pickup reaches the position where the second pickup stops the read operation, the first pickup and the second pickup perform a read (or write) operation again, and repeat the processes of (a) to (d) of FIG. 3. . The Seek operation between (c) and (d) in Fig. 3 should be made while the disc is rotated 1/2 turn (0.5 track), during which the first pick-up and the second pick-up will temporarily stop playing or recording the disc ( 1/2 Slip).

For reference, in FIG. 3, (b) is a state after the disk is rotated by 0.25 laps in (a), (c) is a state after being rotated by 0.5 laps, and (d) is a state after being rotated by 1 lap. to be.

FIG. 4 is a graph representing a movement path of a pickup according to time when two pickups perform a data read or write operation by the method of FIGS. 2 and 3. The inner pickup (red circle in FIG. 3) and the outer pickup ( It can be seen from FIG. 3 that the spacing of the blue circles is kept constant.

FIG. 5 is a diagram illustrating a reading speed or a writing speed of data when two pickups perform a data reading or writing operation by the method of FIGS. 2 and 3. In FIG. 5, a denotes a (d) in FIG. Indicates that the track Seek operation up to) is normally performed, i.e., the first pickup and the second pickup jump the track to the next recording position (1 track jump) while the disc is rotating 0.5 turns.

Thus, when the first pickup normally moves to the position where the second pickup stops playing (or recording) and the second pickup also normally moves to the next recording position, in Fig. 3 (a) to (b)-> (c) The time taken until step (d) is 1 track, i.e., the time at which the disc is rotated once (the time at which the first and second pickups read or write data (Tr) 0.5 track rotation time and the first The amount of data read or recorded between the pickup and the second pickup waiting for the track jump (Tj 0.5 track rotation time), and the amount of data read or recorded between them is the data of one track (0.5 track by the first pickup and 0.5 track by the second pickup). Therefore, the reproduction or recording double speed (or data transfer rate) becomes 1x speed.

In FIG. 5, b indicates that the track Seek operation from (c) to (d) of FIG. 3 is not normally performed, that is, the first pickup and the second pickup are moved to the next recording position while the disc is rotated 0.5 turns. 3 (c), since the disc must turn one more turn to rotate to the place where the first pickup is placed, where the second pickup stops playback (or recording). It takes 1.5 track turns to get to (d). That is, if an abnormal Seek operation occurs, the data rate is lowered.

When two pickups are arranged at track intervals shorter than one track (0.5 tracks for 180 degree batches, 0.25 tracks for 90 degree batches) when multiple reads (or writes) with two beams (or pickups), FIG. 3 It is known that the transfer rate does not increase or the increase efficiency is low when going to step (a) after step (c) after step (c) of the pickup.

As a method for improving this, as shown in FIG. 6, two pickups may be arranged at intervals longer than one track based on the radial direction of the disc, and FIG. 6 illustrates a first pickup (red circle) and a second pickup (blue circle). Is an example arranged at 1.5 track intervals, and FIG. 7 represents the reading speed or the recording speed of data when two pickups having 1.5 track intervals perform a data read or write operation by the method of FIGS. 2 and 6.

In FIG. 6, (b) rotates 0.25 turns in (a), (c) rotates 1.5 turns in (a), and (d) and (e) indicate that the first and second pickups are tracked. While performing the jump, the motor rotates by 0.5 laps in the state (c).

When the track jump is performed normally, the time taken from (a) to (b)-> (c)-> (d) (e) in Fig. 6 is 1.5 times of data reproduction or recording time (Tr). (Or 1.5 tracks) and the time that the pickup takes a track jump so that the tracking servo is stabilized and the disc rotates to the next recording position (Tj), which is the sum of 2 rotation times (2 tracks) of 0.5 rotation time (1.5 tracks), Since the amount of data to be read or recorded in between is 1.5 tracks X 2 = 3 tracks, the reproduction or recording speed (or data transfer rate) is about 3/2 = 1.5 times as shown in FIG.

6 (f) shows the track jump when the disc rotates one more turn if the first pickup and / or the second pickup has track jumped during the half turn of the process from (c) to (e) but fails to track. And an example of retrying the track Seek operation, which corresponds to an abnormal track jump of b in FIG. 7, and when the tracking stabilization time Tj is long, it is difficult to expect an increase in the double speed.

In this way, when the simultaneous read time is increased by increasing the data buffer in the disk device, the speed can be increased more. However, the speed decrease can not be reduced due to the problems of track seek and tracking stabilization. In addition, it is not possible to increase the period of simultaneous reading indefinitely, but if the interval between two pickups is too large compared to the size of the input data, it is not much different from the method of using one pickup, and the time to fill the buffer with the input data can be longer. In-drive buffers also have a finite size.

In the present invention, in order to increase the reproduction or recording speed (rate) when reading or recording data with a plurality of pickups, two or more pickups do not move for the track Seek at the same time, and most pickups read or record data at the same time. The track movement positions and the movement time points of the plurality of pickups can be adjusted so as to increase the time Tr.

8 is an operation flowchart of a multiple pickup reading or writing method according to an embodiment of the present invention, in which two optical pickups are arranged symmetrically about a disk clamp hole to perform a data reading or reproducing operation. An embodiment is shown in FIG. 9.

In the embodiment of Fig. 9, two pickups start a simultaneous read (or write) operation with 1.5 track intervals, with each pickup performing a read operation with the first pickup located in the inner circumference (in red circle in Fig. 9). It is checked whether the reading operation is performed until the reading start point of the second pickup (indicated by the blue circle in FIG. 9), which is the previous pickup located at the outer circumference (indicated by (b) in FIG. 9).

When the first pick-up reaches the start point at which the second pick-up has performed the read operation (state of rotation 1.5 times in (a) by the process of (c) in Fig. 9), the second pick-up continues to perform the read operation, The pickup performs a track Seek operation that moves to a position ahead of the second pickup by a predetermined length (step (d) in FIG. 9), where the position where the first pickup is to be moved is expected to stabilize the tracking servo after the first pickup is moved. It is advantageous to set the position of the second pickup at a time point ahead of the predetermined length (e.g., d1 in FIG. 10).

When the first pickup is moved and the tracking servo is stabilized, the first pickup becomes the pickup located at the outer circumference, the second pickup is the pickup located at the inner circumference, and both pickups continue the read operation at the same time, and the second pickup of the inner ring is the first pickup. When the read start point of the first pickup is reached and the read start point of the first pickup is reached, the second pick-up is moved to a position before the first pick-up (eg, d2 in FIG. 10). This operation is repeated.

Starting from the process (a) of FIG. 9 to the process (c), the disc is rotated by 1.5 revolutions (1.5 tracks) (tr), and after the process (c), the first pickup is moved outward and recorded while the disc is rotated by 0.5 revolutions. If you start reading operation, i.e. if the track Seek operation of the pickup takes place at 0.5 track time (0.5 revolutions) (tj), the time taken is 2 track time (tr + tj = 1.5 + 0.5) and the amount of data detected is Since 3.5 tracks (1.5 x 2 + 0.5), the double speed is 3.5 / 2 = 1.75.

As shown in FIG. 9, in the process of (c)-> (d), when one outermost pickup performs a continuous reading (or writing) operation and jumps the innermost pickup, and performs tracking servo stabilization, a stable double speed (rate) is obtained. Will be secured.

FIG. 10 is a graph illustrating a movement path of a pickup according to time when two pickups perform a data read or write operation in a recording method according to the present invention as shown in FIGS. 8 and 9. It consists of a time interval (tr) in which two pickups simultaneously perform a read (or write) operation and one pickup performs a read operation and the other pickup consists of only a time interval (tj) for moving tracks. As it is longer than this standing section, it can be seen that the speed is improved.

FIG. 11 is a recording method according to the present invention as shown in FIGS. 8 and 9 representing a read speed or a recording speed of data when two pickups perform a data read or write operation. Since the tr section is longer than the tj section, FIG. When Seek and track jump operations (track jump a in FIG. 11) are normally performed, theoretically, a speed of 1.5 times or more can be obtained.

Even in the worst case where the track Seek is delayed as in the track jump b in FIG. 11, more than one pick-up performance is guaranteed since the speed can be guaranteed by the pickup in progress.

In addition, even if the track jump is delayed as in the track jump b, in the conventional method as shown in Figs. Instead of having to wait for the wheels to spin, the read operation can begin immediately at the position where the tracking servo stabilizes after the innermost pickup has moved outward than the outermost pickup. In other words, it is possible to reduce the phenomenon that only one pickup is recorded and the other pickup takes longer time tj.

FIG. 12 illustrates the reading speed or the writing speed of data in various track Seek environments when two pickups perform a data reading or writing operation by the method according to the present invention as shown in FIGS. 8 and 9.

In FIG. 12, track jump a is a normal track jump, for example, jumping 6 tracks during a 0.5 track slim (0.5 wheel revolution), and track jump b performed a jump during 0.5 track slim but 1 track less than 6 tracks. Track 5 jumps, track jump c indicates no track jump for 0.5 track slim and jumps 1 track less than 6 tracks for 1 track slim, track jump d jumps for 0.5 track slim But jumps 7 tracks 1 track more than 6 tracks, and track jump e represents a normal track jump such as track jump b.

As shown in FIG. 12, it may be confirmed that the track jump (or seek) of the pickup is not constant and may be different from each other, and achieves a double speed of 1.5 to 2. FIG.

It is advantageous for combining the data read in each pickup to move the inner pickup outward rather than the outer pickup after the inner pickup performing the read operation reaches the read start point of the outer pickup or slightly past the read start point. The data read from the pickup can be stored in the buffer, decoded and combined with the data read from the other pickup, thereby eliminating redundant portions.

An optical disc device including a plurality of optical pickups may store for each pickup a starting point at which the pickup starts reading and update it each time the pickup moves and starts reading again, and the data of the pickup of the next week may be decoded or read on the track. By detecting the formed address information, the position where the read operation is in progress can be checked and compared with the start point of the outer pickup to determine whether the inner pickup has reached the reading start point of the outer pickup.

Alternatively, the optical disk device compares the reading start point of the inner pickup with the reading start point of the outer pickup, predicts the time when the inner pickup reaches the reading start point of the outer pickup from the point at which the inner pickup starts reading, and reaches the predicted time. Alternatively, when a predetermined time elapses from the predicted time, it is determined that the inner pickup has reached the reading start point of the outer pickup, and the inner pickup can be moved to the outer circumference.

When performing a recording operation, it is advantageous for each pickup not to record the data in any size but to record the data in a predetermined recording unit to which at least one address can be assigned, for example in an error correction unit, each pickup It is advantageous to start data recording from a position at which data of a predetermined recording unit is to be recorded.

In addition, unlike the simultaneous read operation, the inner pickup that performs the write operation must move the track to a position ahead of the outer pickup after exactly reaching the write start point of the outer pickup. Reduces the power of the laser diode from power for recording to power for playback, and performs track jumps and track seeks.

The pickup moved to the outer periphery detects the position information formed on the track (land / groove) where data is to be recorded when the tracking servo is stabilized, and judges based on the detected position information to reach the start point of the predetermined recording unit. The power of can be raised to the power for recording and the recording operation can be continued.

The optical disk apparatus including the plurality of optical pickups predetermines the starting point position at which the first pickup moved starts the recording when the first pickup in the inner circumference arrives at the recording start point of the second pickup in the outer circumference. After the first pickup is moved to the vicinity of the starting point while the data to be recorded from the starting point is stored in the buffer for the first pick-up, the tracking servo is stabilized, and the position information recorded on the track is detected. The recording operation can be started.

Or, when the optical disk device moves the first pickup in the inner circumference to the outer circumference, the first pickup does not accurately determine the starting point position at which to start recording, and the first pickup is a predetermined length ahead of the second pickup in the outer circumference. When the tracking servo of the first pickup is stabilized and the position information is detected from the track, the data to be recorded is stored in the buffer for the first pickup from the recording start point of the predetermined recording unit after the detected position and the starting point In this case, the recording operation by the first pickup may be started.

13 and 14 illustrate embodiments in which the placement of pickups and / or the number of pickups are varied.

In the embodiment of FIG. 13 the optical disk device comprises two pickups, but unlike the embodiment of FIG. 9, the two pickups are arranged at an angle less than 180 degrees, for example 45 degrees, with respect to the disc clamping hole. have. The operating principle of the embodiment of FIG. 13 is not significantly different from the embodiment of FIG. In the embodiment of Fig. 13, the two optical pickups share a base with each other so that the inner and outer conveyance of the optical pickup can be made by one sled motor. At this time, the angle of 45 degrees formed by the two pickups (exactly the objective lens) is just one example of an acute angle, and two optical pickups may be mounted on one base so that they can be transported by one sled motor.

In the embodiment of FIG. 13, since the optical disk device requires only one sled motor, mechanical implementation of the device is easier than in the embodiment of FIG. 9, in which a sled motor is installed on both sides of the disk. Instead, one sled motor and two pickup actuators must be properly driven to smoothly move the laser beam from the two pickups around and around.

FIG. 14 illustrates an embodiment in which four pickups are disposed at 90 degrees to each other, and two pickups are disposed at a 45 degree angle with respect to the disc clamping hole and the other two pickups are arranged at a 45 degree angle. It may be arranged symmetrically with respect to the clamping hole. In the embodiment of Fig. 14, two or more pickups can be moved simultaneously from the inner circumference to the outer circumference by adjusting the position at which each pickup starts recording (track interval between each pickup).

Fig. 15 represents the reading speed or the writing speed of data when performing a data read or write operation with three pickups according to the method according to the present invention. Since only a section in which a read operation is performed or three pickups perform a read operation simultaneously, speeds of 2 to 3 times can be obtained.

16 and 17 show when data is read from or written to a disc by two pickups, the data read from the two pickups are combined to be transferred to the host or the data transmitted from the host is divided into two pickups. An example is shown. During the pickup or reading of the outer periphery, the pickup of the inner periphery moves to the outer periphery for a Tj time to read the data recorded on the outer periphery or to receive and record data to be recorded on the outer periphery.

As in the above-described embodiment of the present invention, when performing a read or write operation using N pickups, N pickups simultaneously perform reading for Tr time and only the innermost pickup moves to the outermost time during Tj time. When tracking is stabilized and the rest of the pickups perform a read operation, the speed increases by (N xf (Tr) + (N-1) xf (Tj)) / f (Tr + Tj) rather than one pickup, where f (T) is the amount of data that one pickup reads or writes during T time.

Further, in order to improve the speed, if the time Tj until the pickup of one or more inner races moves to the outer periphery and stabilizes, the time Tj is relatively small compared to the time Tr in which all or multiple pickups simultaneously perform a read or write operation. It is advantageous. At this time, there is no significant difference in the number of tracks to be skipped or the time to stabilize the tracking servo when the innermost pickup moves outward. Instead, if a pickup moved outward has a predetermined start position (a position on the circumference of the disc) at which to start reading or writing, the time to reach that start position is also related to the rotation of the disc. There may be an unnecessary slip operation until reaching the pickup moved outward, and the time required for the slip operation may occupy a large part of Tj.

Therefore, in the present invention, the radial direction is determined when the innermost pickup that has reached the start point of the next pickup is moved so that the innermost pickup moves to the outermost circumference to reduce the time Tj until the start of the read or write operation. The position in the circumferential direction may be limited and the position may be roughened. That is, the track jump is performed by a predetermined number of tracks or a predetermined length away from the outermost pickup, and when the tracking servo is stabilized after moving, perform a read or write operation regardless of the position in the circumferential direction. can do.

At this time, the position on the circumference is not fixed in the read operation and may be any position after the tracking servo stabilization without limitation, but in the recording operation, it is advantageous to start recording at the start of a predetermined recording unit after the tracking servo stabilization.

On the other hand, when the playback or recording direction goes from the outer circumference to the inner circumference, as in the second recording layer of the dual layer, the innermost pickup is picked up by the track jump when the outermost pickup reaches the reading start point or the writing start point of the pickup located further in the inner circumference. A predetermined length can be moved further inward to restart the read or write operation.

That is, when reading data from or writing data to a disc with two or more pickups, the first pickup, which is operated last in the read or write progress direction, causes the second pickup, which operates immediately before the first pickup, to read or write. When the start position is reached, the read or write operation can be started by moving a predetermined length forward than the third pickup operating in the forward direction.

The above-described preferred embodiments of the present invention are disclosed for purposes of illustration, and those skilled in the art can improve, change, and substitute various other embodiments within the technical spirit and scope of the present invention disclosed in the appended claims below. Or addition may be possible.

11: spindle motor 12: sled motor
20: optical pickup 30: optical drive unit
40: digital signal processing unit 50: RF unit
60: servo / drive unit 70: control unit

Claims (13)

Checking whether the first pickup reaches a read or write start point of a second pickup that is in a read or write process immediately prior to itself;
Moving the first pick-up to reach a position before the second pick-up or the third pick-up in the read or write progress direction after the first pick-up reaches the starting point as a result of the checking; And
And resuming reading or writing from a position at which the first pickup has moved. The method of claim 1,
And the circumferential position at which the first pickup starts reading or writing again is not fixed. The method of claim 2,
And the circumferential position at which the first pickup is to resume reading is an arbitrary position after the first pickup is moved and the tracking servo is stabilized. The method of claim 2,
And the circumferential position at which the first pickup starts writing again becomes a starting point of a predetermined recording unit after the first pickup is moved and the tracking servo is stabilized. The method of claim 1,
The checking includes comparing a current position obtained by decoding data read by the first pickup or by detecting address information formed on a disc, with a starting point stored for the second pickup,
The resuming may further include updating and storing a position at which the first pickup starts reading or writing again. The method of claim 1,
When the first pickup that performs the write operation reaches the start point, the power of the laser diode of the first pickup is reduced to the regeneration power, and the power of the laser diode is adjusted to the recording power when the write operation is resumed after moving. An optical disc control method using a plurality of pickups.
A plurality of optical pickups;
A recording / reproducing section for driving the optical pickup and processing signals and data; And
A control unit for controlling the recording / reproducing unit,
The controller checks whether the first pickup reaches the read or write start point of the second pickup that is being read or written in advance of itself, and the read or write proceeds after the first pickup reaches the start point. And moving the first pickup so as to reach a position before the second pickup or the third pickup, which is earlier in the direction, by a predetermined length, and controlling to start reading or writing again from the position where the first pickup is moved. Disk device. The method of claim 7, wherein
The plurality of optical pickups comprise a first pick-up and a second pick-up arranged symmetrically about a disk clamp hole, wherein the first pick-up and the second pick-up are conveyed by another sled motor. Device. The method of claim 7, wherein
The plurality of optical pickups are composed of a first pickup and a second pickup disposed at an acute angle around the disc clamp hole, and the first pickup and the second pickup are conveyed by one sled motor. Disk device. The method of claim 7, wherein
Wherein the circumferential position at which the first pickup starts reading again is not fixed and becomes an arbitrary position after the first pickup is moved and the tracking servo is stabilized. The method of claim 7, wherein
And the circumferential position at which the first pickup starts writing again is not fixed and becomes the starting point of a predetermined recording unit after the first pickup is moved and the tracking servo is stabilized. The method of claim 7, wherein
The control unit controls the recording / reproducing unit to compare a current position obtained by decoding data read by the first pickup or by detecting address information formed on a disc, with a starting point stored for the second pickup, and comparing the first pickup with the first pickup. And updating the position at which the read or write is resumed and storing it in the memory. The method of claim 7, wherein
The control unit controls the recording / reproducing unit to reduce the power of the laser diode of the first pickup to the reproduction power when the first pickup performing the write operation reaches the start point, and when the write operation is resumed after the movement. An optical disk apparatus characterized by adjusting the power of a laser diode to recording power.

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