KR19990035343A - Track Jump Control Method of Optical Disc System - Google Patents

Abstract

A track jump control method of an optical disc system using a track jumper that jumps an optical pickup unit having an objective lens and a tracking actuator coil therein to a target track on a disk. Jumping in a target track direction; When the optical pickup unit reaches a target track, stopping the jump operation and detecting a track jump direction; And providing a predetermined current to the tracking actuator coil so that the objective lens moves in a direction opposite to the track jump direction.

Description

Track Jump Control Method of Optical Disc System

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a track jump control method for jumping an optical pickup unit to a predetermined track position on a disc in an optical disc system.

In general, an optical disc system is a system for non-contact reproduction of information engraved on a disc by a laser beam and digital signal processing. One of the main features of such an optical disc system is random access to a playback position on a disc. Can be done. Therefore, in the optical disc system, even when playing a track in which a predetermined song is recorded, when a signal for instructing playback of another song is input, the optical disc system immediately searches for the start position of the track in which the song corresponding to the instruction signal is recorded. It is equipped with a function to enable playback.

Such a function is generally referred to as a track search function. The track jump device is a track jump device that substantially performs the track search function. The track jump device will be described below with reference to FIGS. 1 and 2.

FIG. 1 is a schematic diagram of an optical pickup unit that reads information on a disc by a laser beam and converts the information into an electrical signal. FIG. 2 is a schematic diagram of a track jump apparatus for performing track search. Shown.

In Fig. 1, a predetermined sequence of information is recorded on a disc 10 along a track, and the optical pickup unit 20 emits a laser beam focused by the objective lens 21 on the track of the disc 10. Then, by receiving the light reflected from the track of the disk 10 and converts it into an electrical signal, it serves to read the information recorded on the disk.

On the other hand, in reading out the information recorded on the disk, the disk 10 is actually in a rotating state, and the optical pickup unit 20 is to trace the track of the rotating disk.

Referring to FIG. 2, the error detector 30 generates and outputs a pulse corresponding to each time the optical pickup unit 20 crosses a track without tracing a track of the disc 10. The counter 40 counts the number of pulses output from the error detector 30 and provides it to the microcomputer 50, and the microcomputer 50 can know the crossing distance of the optical pickup unit 20 based on the count value. Therefore, even when the optical disc system is performing normal playback, when an instruction signal for jumping the optical pickup unit 20 to a predetermined position on the disc 10 is input, the microcomputer 50 controls the driver 60 to pick up the optical pickup. After the unit 20 is jumped to a predetermined position, the optical pickup unit 20 determines the jump position by referring to the count value generated in the process of traversing the track of the disk 10, and then the optical pickup unit 20 When the indicated predetermined position is reached, the track jump operation is completed, and then the standby state is maintained for a predetermined time, and then a subsequent operation, for example, a reproduction operation is performed.

Here, the reason for waiting for a predetermined time after completion of the track jump is as follows. That is, after the optical pickup unit 20 completes the track jump operation, the objective lens 21 inside the lens 21 becomes unstable due to inertia or the like. If the objective lens becomes unstable, the focusing servo (the function of controlling the signal plane of the disk to be located within the depth of focus of the laser beam) and the tracking servo (the function of controlling the laser beam to accurately track the track of the disk) will not work properly. If you play the disc in this state, an error may occur. Therefore, conventionally, the object lens 21 waits until it becomes stable and then performs the next operation.

However, in the related art, since the reproduction is performed after waiting until the objective lens is stabilized in this way, there is a problem in that a slight time delay occurs.

The present invention has been made to solve the above problems, and an object thereof is to provide a track jump control method in which an objective lens can be stabilized more quickly after completion of a track jump.

The present invention provides a track jump control method for an optical disc system using a track jumper for jumping an optical pickup unit having an objective lens and a tracking actuator coil to a target track on a disc. If determined, jumping the optical pickup unit toward a target track; When the optical pickup unit reaches a target track, stopping the jump operation and detecting a track jump direction; And providing a predetermined current to the tracking actuator coil so that the objective lens moves in a direction opposite to the track jump direction.

1 is a view showing a schematic configuration of an optical pickup unit;

2 is a view showing a track jumping device of the prior art,

3 is a hardware configuration diagram for performing a track jumping method of the present invention;

4 is a detailed flowchart illustrating a preferred embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

100: disk 110: optical pickup unit

120: error detection unit 130: counter

140: first driving unit 150: second driving unit

160: micom

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

3 shows hardware for performing the track jump control method of the present invention.

In FIG. 3, the hardware for performing the track jump control method of the present invention includes a disk 100, an optical pickup unit 110 having an objective lens 110a and a tracking actuator coil 110b therein, and an error detector. 120, the counter 130, the first driver 140, the second driver 150, and the microcomputer 160.

In this case, in FIG. 3, the disk 100, the optical pickup unit 110, the error detector 120, the counter 130, the second driver 150, and the microcomputer 160 are substantially the conventional illustrated in FIG. 2. It is the same structural member which performs the same function as each structural member with respect to the track jumper of a technique, and detailed description is abbreviate | omitted.

In addition, the tracking actuator coil 110b serves to adjust the objective lens 110a so that the laser beam of the optical pickup unit 110 can accurately track the track of the disc. It will be appreciated that this tracking actuator coil 110b is already mounted to the conventional optical pickup unit 110, rather than to a newly added component member for the present invention.

When the track jump is completed, the first driver 140 serves to stabilize the objective lens 110a by providing a predetermined current to the tracking actuator coil 110b.

On the other hand, the above-mentioned microcomputer 160 controls the overall operation of the track jump, and has a function of controlling the first drive unit 140 to operate when the track jump is completed.

4 is a detailed flowchart illustrating a track jump control method according to a preferred embodiment of the present invention. The track jump control method shown in FIG. 4 is performed using the hardware of FIG. 3 described above, and therefore, the track jump control method of the present invention will be described below with reference to FIGS. 3 and 4.

First, when the track jump instruction is input from the outside (S1), the microcomputer 160 determines the track jump direction. For example, if the target track to which the optical pickup unit 110 should jump is located in the outer circumferential direction from the current position of the disc 110, it is determined that the track jump direction is forward, and the target track to which the optical pickup unit 110 should jump to If the disc 110 is located in the inner circumferential direction from the current position of the disc 110, it is determined that the track jump direction is the reverse direction.

As a result of the determination of the microcomputer 160, if it is a forward jump (S2), the microcomputer 160 controls the second driver 150 to cause the optical pickup unit 110 to jump in the forward direction (S3), and if it is a reverse jump (S2). After controlling the second driving unit 150 to allow the optical pickup unit 110 to jump in the forward direction (S4), data about the jumping direction is stored in the internal memory.

Accordingly, the second driver 150 jumps the optical pickup unit 110 to the target track under the control of the microcomputer 160.

Meanwhile, the error detector 120 generates and outputs a pulse corresponding to the optical pickup unit 110 whenever the optical pickup unit 110 traverses the track of the disk 100. The counter 130 counts the number of pulses output from the error detector 120 and provides the count to the microcomputer 160. The microcomputer 160 determines whether the optical pickup unit 110 is approaching the target track based on the count value. Determine.

When the optical pickup unit 110 reaches the indicated target track (S5), the microcomputer 160 determines that the track jump is completed, and then controls the second drive unit 150 to stop the track jump (S6).

Then, the microcomputer 160 determines the jump direction by referring to the jump direction data stored in the internal memory (S7), and then controls the first driver 140 to move the objective lens 110a in the opposite direction to the jump direction. .

The first driver 140 provides a forward current (eg, + current) or a reverse current (eg, -current) to the tracking actuator coil 110b under the control of the microcomputer 160. That is, when the jump direction is the forward direction, the first driver 140 supplies a reverse current to the tracking actuator coil 110b (S8), and when the jump direction is the reverse direction, the first driver 140 is the tracking actuator. The forward current is supplied to the coil 110b (S9).

Therefore, after the optical pickup unit 110 jumps in the forward direction, a reverse force is applied to the objective lens 110a inside the optical pickup unit 110, and after the optical pickup unit 110 jumps in the reverse direction, the optical Forward force is applied to the objective lens 110a in the pickup unit 110, and the objective lens 110a is stopped from shaking.

As described above, the present invention determines the track jump direction of the optical pickup unit. After the optical pickup unit jumps in the forward direction, a reverse force is applied to the objective lens inside the optical pickup unit, and the optical pickup unit jumps in the reverse direction. Afterwards, forward force is applied to the objective lens inside the optical pickup unit, whereby the objective lens that is shaken by inertia can be stabilized more quickly.

Claims (1)

In a track jump control method of an optical disc system using a track jumper for jumping an optical pickup unit having an objective lens and a tracking actuator coil therein to a target track on a disc: If the target track is determined, jumping the optical pickup unit in a target track direction; When the optical pickup unit reaches a target track, stopping the jump operation and detecting a track jump direction; And providing a predetermined current to the tracking actuator coil so that the objective lens moves in a direction opposite to the track jump direction.