JPH08235600A - Optical disk player device - Google Patents

Abstract

PURPOSE: To stably and speedily conduct seek operation for moving an optical beam to a target track by making a fine abjustment actuator immobile for a prescribed time when moving the optical beam from an optical device more than a prescribed distance. CONSTITUTION: When the moving seek operation of a laser beam from an optical pickup beyond the control range of a tracking actuator is required, a seek-on signal is supplied to a monomultivibrator 11. Then, during the period of a time constant, a connection switch 9 is turned off and the tracking actuator is made immobile for this period of time. Thus, only the actuator is not operated early but it is stably operated together with a linear motor and an objective lens is not moved out of a view field. Therefore, it takes a small time before stabilizing the tracking, focus deviation becomes smaller and faster seek operation is realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has an optical device capable of recording information on or reading information from an optical disc such as a compact disc player device, and outputs a light beam from the optical device. The present invention relates to an optical disk player device having a tracking servo circuit composed of a coarse movement actuator which moves to a target track and a fine movement actuator which holds a light beam from this optical device at the center of the track.

[0002]

2. Description of the Related Art Generally, a compact disc player device is provided with an optical pickup 2 for reading information from an optical disc 1 as shown in FIG. As a driving device for moving the laser beam emitted from the optical pickup 2 to a target track of the optical disc 1 and holding it, a focusing actuator that always keeps the focus of the laser beam on the recording surface of the optical disc 1, and the laser beam A tracking actuator, which is a fine movement actuator held at the center of the track, and a linear motor 3, which is a coarse movement actuator that cooperates with the tracking actuator to move the laser beam to a target track, are provided.

The linear motor 3 is designed to move the optical pickup 2 as a whole, and is driven by a seek signal and a tracking error signal from a microcomputer constituting a control device.

The focusing actuator and the tracking actuator are provided in the optical pickup 2 and the biaxial lens actuator 4 for moving the objective lens 2a in the focusing direction and the tracking direction.
Has been made.

In FIG. 2, 3a is a linear motor 3
Drive coil, 3b is a center yoke, 3c is a magnet, 3d is a guide shaft that determines the moving direction, 3e is a bearing, and 5 is a speed sensor, 5a and 5b are coils forming this speed sensor 5, and It is a magnet.

Conventionally, the linear motor (coarse movement actuator) 3 and the tracking actuator (fine movement actuator) 4 form a tracking servo circuit, and cooperate with each other as shown in FIG. It is designed to move to the target track and track.

That is, in FIG. 3, reference numeral 6 denotes a control signal input terminal to which a tracking error signal and a seek signal are supplied. The tracking error signal and the seek signal supplied to the control signal input terminal 6 are passed through a low pass filter 7. The tracking error signal and the seek signal supplied to the drive coil 3a of the linear motor 3 and the control signal input terminal 6 are supplied to the coil 4a of the tracking actuator through the high pass filter 8 to apply the tracking servo and the seek operation. I'm trying to do it.

When the laser beam from the optical pickup 2 is moved from the x ₀ point to the x ₁ point of the optical disk 1 by the seek operation, a seek signal, that is, a drive voltage is used as a seek signal shown in FIG. 4A.
This laser beam as shown in Supply a positive voltage while moving A negative voltage is supplied during the movement of the distance, and the relationship between the moving speed of this laser beam and the distance gradually increases from the starting point x ₀ to the intermediate point as shown in FIG. next, gradually reduce the speed towards the end x ₁ from the intermediate point and as the speed becomes zero at the end point x _1.

[0009]

The conventional tracking servo circuit composed of such a linear motor (coarse actuator) 3 and a tracking actuator (fine actuator) 4 operates well without any problem in a normal tracking servo. During the seek operation, the response of the linear motor 3 to the drive voltage is much slower than the response of the tracking actuator 4. For example, when the step drive voltage is as shown in FIG. 5A, the step response of the secondary system of the linear motor is As shown in FIG. 5B, the step response of the secondary system of the tracking actuator as shown in FIG. 5C is significantly slowed down. Therefore, only the tracking actuator 4 operates first due to the drive voltage of the seek operation. The movable part of 4 is the holding part Since the objective lens 2a swings out of the field of view due to the contact with the upper part) and a hit sound is generated, it takes time until the tracking becomes stable, and at this time, the focus is deviated and it takes time to adjust the focus. There was an inconvenience that the seek operation took a long time.

The present invention has been made in view of the above problems, and an object of the present invention is to perform a seek operation for moving a light beam to a target track stably and quickly.

[0011]

The optical disk player device of the present invention has an optical device 2 capable of recording information on or reading information from the optical disk 1 as shown in FIG. 1, for example. An optical disk player device having a tracking servo circuit comprising a coarse actuator 3 for moving a light beam from the device 2 to a target track and a fine actuator 4 for holding the light beam from the optical device 2 at the center of the track. The fine movement actuator 4 is made inoperative for a predetermined time when the light beam from No. 2 is moved for a predetermined distance or more.

According to the present invention, since the fine movement actuator 4 is kept inactive for a predetermined time during the seek operation for moving the light beam from the optical device 2 by a predetermined distance or more, only the fine movement actuator 4 does not operate first. Since the objective lens 2a does not swing outside the field of view because it operates together with the coarse movement actuator 3, it does not take time to stabilize tracking, and there is little defocusing, etc., so that a seek operation can be performed quickly. I can.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the disc player device of the present invention will be described below with reference to FIGS. In FIG. 1, parts corresponding to those in FIGS. 2 and 3 are designated by the same reference numerals, and detailed description thereof will be omitted.

Also in this example, the optical disc 1 is used as in FIG.
An optical pickup 2 for reading information from the optical pickup 1 is provided, and a drive device for moving and holding the laser beam emitted from the optical pickup 2 to a target track of the optical disc 1 is provided.

This optical pickup 2 is used as this drive device.
Focusing actuator that always keeps the focus of the laser beam on the recording surface of the optical disc 1, a tracking actuator that is a fine movement actuator that keeps the laser beam at the center of the track, and the laser beam in cooperation with the tracking actuator. A linear motor 3 that is a coarse actuator that moves to a target track is provided.

The linear motor 3 is arranged so that the entire optical pickup 2 is placed and moved, and is driven by a seek signal and a tracking error signal from a microcomputer constituting a control device.

Further, the focusing actuator and the tracking actuator are the optical pickup 2
The lens actuator 4 is provided inside and has a biaxial lens actuator 4 that moves the objective lens 2a in the focus direction and the tracking direction.

In this case, the linear motor (coarse movement actuator) 3 and the tracking actuator (fine movement actuator) 4 constitute a tracking servo circuit.

In this example, the linear motor (coarse movement actuator) 3 and the tracking actuator (fine movement actuator) 4 are constructed as shown in FIG. That is, the tracking error signal and the seek signal supplied to the control signal input terminal 6 are supplied to the drive coil 3a of the linear motor 3 through the low pass filter 7, and the tracking error signal and the seek error signal supplied to the control signal input terminal 6 are supplied. The seek signal is supplied to the coil 4a of the tracking actuator 4 through the series circuit of the high pass filter 8 and the connection switch 9.

Reference numeral 10 denotes a seek-on signal input terminal. The seek-on signal input terminal 10 has a control range (controllable distance) of the tracking actuator 4 during seek operation by a microcomputer constituting a control device.
When the above-mentioned movement of the laser beam is required, a seek-on signal is generated and this seek-on signal is supplied.

This seek-on signal is supplied to the mono-multivibrator 11, and the connection switch 9 is turned off during this pulse period by a pulse of a predetermined width obtained at the output side of the mono-multivibrator 11. The time constant of the mono-multi vibrator 11 is the linear motor 3 during seek operation.
The time when the synergistic relationship between the tracking actuator 4 and the tracking actuator 4 is best determined by cut and try.

In this case, the time when the synergistic relationship between the linear motor 3 and the tracking actuator 4 is best corresponds to the step response delay time determined by the weight of the linear motor 3 and the like.

Others are the same as those of the conventional optical disk player device.

Since the present embodiment is configured as described above, when the seek operation for moving the laser beam from the optical pickup 2 beyond the control range (controllable distance) of the tracking actuator 4 is requested, the seek-on signal is a mono-multi signal. The tracking switch 4 is supplied to the vibrator 11, and the connection switch 9 is turned off for this time constant time, and the tracking actuator 4 is inactive for this time. Therefore, only the tracking actuator 4 does not operate first, but operates with the linear motor 3. Therefore, the objective lens 2a does not swing outside the field of view, so that it takes less time until the tracking becomes stable and there is less defocusing, so that there is an advantage that a quick seek operation can be performed.

During normal tracking servo, the connection switch 9 remains on, so that good tracking servo can be applied as in the conventional case.

Although an example using a laser beam has been described in the above embodiments, other light beams may be used instead of this, and an example using the present invention in a reproducing apparatus has been described in the above embodiments. It can be easily understood that the present invention can also be applied to a recording device that records information on an optical disc by a light beam from the device. Although the linear motor 3 is used as an example of the coarse movement actuator in the above-described embodiment, another coarse movement motor may be used instead.

Further, the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0028]

According to the present invention, there is an advantage that the seek operation of moving the light beam to the target track can be performed stably and quickly.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a main part of an embodiment of an optical disc player device of the present invention.

FIG. 2 is a schematic diagram for explaining an example of an optical disc player device.

FIG. 3 is a configuration diagram showing an example of a main part of a conventional optical disc player device.

FIG. 4 is a diagram for explaining the present invention.

FIG. 5 is a diagram for explaining the present invention.

[Explanation of symbols]

1 optical disk, 2 optical pickup, 2a objective lens, 3 linear motor, 3a drive coil, 4 lens actuator (tracking actuator), 4a
Coil, 6 control signal input terminal, 7 low pass filter, 8 high pass filter, 9 connection switch, 10
Sequon signal input terminal, 11 mono multivibrator

Claims (1)

[Claims] 1. A coarse movement actuator having an optical device capable of recording information on or reading information from an optical disc and moving a light beam from the optical device to a target track, and the optical device. In an optical disk player device having a tracking servo circuit composed of a fine movement actuator for holding the light beam of the above in the center of the track, the fine movement actuator is made inoperative for a predetermined time when the light beam from the optical device is moved for a predetermined distance or more. An optical disc player device characterized in that