JPH10312546A - Optical-disk driving method and optical disk apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical-disk driving method and an optical disk apparatus in which a stepping motor is used for a carriage servo system. SOLUTION: An optical disk apparatus is provided with a spindle motor 5, with an optical pickup 2 which reproduces recorded information and with a feed motor 8. It is provided with an RF amplifier 9 which generates the displacement amount (TE) of a track position from the optical pickup 2, with a window comparator which detects that the amplitude of a signal TE exceeds a first reference value, with a direction-of-rotation control comparator which detects whether the value of the signal TE is positive or negative with reference to a second reference value, with a pulse generation circuit 32 and with a pulse- train changeover circuit 34. A stepping motor 27 is used as the feed motor 8. Therefore, it is possible to provide the optical disk apparatus which can perform a high-accuracy positioning control operation and a high-speed access operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a DVD and a CD-RO.
The present invention relates to an optical disk drive method and an optical disk device for reproducing or recording information on an optical disk such as M.

[0002]

2. Description of the Related Art Conventionally, optical disks (DVD, CD-RO) have been used.
M), a lead screw method is generally employed as a transport means of the optical pickup in the tracking control, and a drive source for rotating the lead screw is a DC source.
Motors have been used.

FIG. 5 is a configuration diagram of a conventional optical disk drive. Hereinafter, the operation of the conventional optical disk device will be described using a CD-ROM as an example with reference to FIG. In FIG. 5, 1 is an optical disk (CD-ROM), 2 is an optical pickup, and 4 is an objective lens. Reference numeral 5 denotes a spindle motor that drives the optical disk 1 to rotate. Reference numeral 6 denotes a screw shaft provided with a spiral groove, 7 denotes a gear for transmitting rotation to the screw shaft, and 8 denotes a DC motor (feed motor) serving as a rotation drive source of the screw shaft 6.

9 is an RF amplifier, 10 is a driver for driving the DC motor 8, 11 is a driver for the tracking coil, 12 is a tracking servo circuit, 13 is a controller, 14 is a signal processing circuit, 15 is a host IF (interface), Reference numeral 16 denotes a host, 17 denotes a spindle motor driver, 18 denotes a spindle motor control circuit, 19 denotes a focus servo circuit, and 20 denotes a focus control driver.

The information recorded on the optical disk 1 is reproduced by the optical pickup 2, and the output signal of the optical pickup 2 is R
The signal is amplified by the F amplifier 9 and supplied to the signal processing circuit 14 as an information signal. The controller 13 is a signal processing circuit 1
A torque command signal is output to the spindle motor control circuit 18 based on the information signal of No. 4. Thus, the spindle motor 5 is controlled by the CLV (constant linear velocity) via the spindle motor driver 17.

The output signal of the optical pickup 2 is converted to an RF signal.
The information signal amplified by the amplifier 9 generates an FE (focus error) signal, a TE (tracking error) signal, an RF (information) signal, and the like. The FE signal is subjected to signal processing by a focus servo circuit 19 and output to a focus servo driver 20, and drives the objective lens 4 in a focus direction (vertical direction of the optical disc 1) by a focus actuator (not shown).

[0007] The TE signal is input to the tracking servo circuit 12. The tracking servo circuit 12 includes two systems of control circuits (see FIG. 7) for controlling the tracking coil 21 (see FIG. 6) and the DC motor 8 provided in the optical pickup 2, respectively. The TE signal is subjected to signal processing by respective control circuits, drives the objective lens 4 in the tracking direction (disc radial direction) via a driver 11 for a tracking coil 21, and passes through a driver 10 for driving a DC motor 8. Then, the DC motor 8 is rotated to move the optical pickup 2 along the screw shaft 6 via the gear 7.

In this way, the optical pickup 2 is controlled to follow the information track of the optical disk 1, and the information signal can be reproduced. The information signal is demodulated and error-corrected by the signal processing circuit 14 to become valid data.
It is sent to the host 16 via the host IF 15. Also,
The controller 13 controls the operation of each of these blocks.

FIG. 6 is a configuration diagram of the optical pickup 2.
6, reference numeral 2 denotes the above-described optical pickup, 3 denotes a carriage for moving the optical pickup 2 in the radial direction of the optical disc 1, 4 denotes an objective lens, 21 denotes a tracking coil,
2 is a magnet. Hereinafter, the structure of the optical pickup will be described with reference to FIG. The carriage 3 has an objective lens 4, a tracking coil 21, and a magnet 22, and the objective lens 4 (bobbin)
The carriage 1 moves on the carriage 3 by the electromagnetic force between the magnet 22 and the magnet 22 by the current flowing through the carriage 1. The carriage 3 moves on the screw shaft 6 in FIG.

FIG. 7 shows the tracking servo circuit 12 shown in FIG.
FIG. In FIG. 7, 9 is an RF amplifier, the system of the tracking coil 21 is continued, 23 is an equalizer for controlling the tracking coil 21, 24 is an amplifier for amplifying the control signal of the tracking coil 21, 11 is a driver for the tracking coil 21, 21 is a tracking coil. On the other hand, in the system of the DC motor 8, 26 is an equalizer for controlling the DC motor 8, 25 is an amplifier for amplifying the control signal of the DC motor 8, 10 is a driver for driving the DC motor 8, and 8 is a DC motor.

The operation of the conventional optical disk drive will be described below with reference to FIG. Based on the TE signal among the signals amplified by the RF amplifier 9, a signal (hereinafter, referred to as an HE signal) for controlling a minute movement of the objective lens is generated by an equalizer 23 for controlling the tracking coil 21. This HE signal is amplified as required by an amplifier 24 for amplifying the control signal of the tracking coil 21.
The tracking coil 21 is driven by the driver 11 for the tracking coil 21. The control system that causes the objective lens 4 of the optical pickup 2 to follow the information track of the optical disc 1 by the tracking coil 21 based on the TE signal is called a tracking servo system.

Further, the TE signal is further branched and input to an equalizer 26 for controlling the DC motor 8, and a seek error signal (hereinafter referred to as SE signal) for controlling the movement of the carriage 3 engaged with the screw shaft 6 is provided. Generated.
The SE signal is amplified as required by an amplifier 25 for amplifying a control signal of the DC motor 8, and the DC motor 8 is driven by a driver 10 for driving the DC motor 8. Thus, the carriage 3 is moved to the objective lens 4 based on the TE signal.
Is called a carriage servo system.

[0013]

In the information signal reproducing operation of the optical disk device, it is necessary to make the carriage smoothly follow the objective lens. This is because if the followability of the carriage servo system is poor, the quality of the information signal detected by the optical pickup deteriorates, and correct data cannot be obtained. It is also important to shorten the time required for the operation (access operation) of moving the optical pickup to the target disk position in order to quickly read and transfer the data requested by the host.

As described above, in a conventional carriage servo system, a lead screw system using a DC motor has been generally used as a carriage driving means. In this lead screw method, it is difficult to control the rotation angle smoothly due to the characteristics of the DC motor.
Positioning could only be done in approximately half-turn units. Therefore, in order to finely control the position of the carriage with respect to the objective lens, or to accurately position the carriage at a target position in the access operation, a high-resolution encoder and a gear unit with a high reduction ratio are required. Become.
As a result, although it is excellent to move the carriage at a low speed, it is difficult to move the carriage at a high speed in the access operation.

In addition, when an optical pickup having a large mass such as a recordable optical system is used, a high-torque DC motor is required, so that the outer dimensions of the motor become large, and there is a limit to miniaturization of the apparatus. is there.

Furthermore, in the lead screw system, a drive signal (drive power) of a required level or more must be given in order to rotate the DC motor by overcoming a loss in the drive system such as mechanical friction of gears. Therefore, actually DC
There is also a problem that extra power is consumed before the motor starts rotating.

In order to solve these problems, it is conceivable to use a stepping motor having a high torque characteristic. The purpose of the stepping motor is to apply a characteristic that positioning control of a minute rotation angle can be performed in accordance with a pulse train signal, and loss is small and high-speed rotation is possible. In order to use this stepping motor in a closed loop control system such as a conventional carriage servo system,
Digitize the above SE signal by AD converter,
Signal processing for generating a pulse train signal for controlling the rotation amount of the motor in accordance with the digital level and sending it to the driver is required.

However, in order to realize such processing by hardware, a complicated circuit is required. Also, if software processing is to be performed by the CPU, the load on the CPU increases, causing another problem that other processing cannot be performed at high speed. Therefore, it is required to apply a simple configuration of the stepping motor drive circuit to the carriage servo system of the optical disk device.

In order to solve the above-mentioned problems, the present invention makes it possible to apply a stepping motor to a carriage servo system by using a circuit having a simple and inexpensive structure, and has a high-precision positioning control performance and a high-speed access operation. It is another object of the present invention to provide an optical disk drive method and an optical disk apparatus which enable a large-mass optical pickup to be incorporated and driven by a high torque characteristic.

[0020]

SUMMARY OF THE INVENTION An optical disk rotation driving means for mounting and rotating an optical disk, an optical reproducing means for irradiating the optical disk from a light source and reproducing information recorded on the optical disk based on the reflected light, An optical disc device having a moving means for moving an optical reproducing means in a radial direction of an optical disc, wherein a track displacement for generating a displacement amount between an information recording position of the optical disc and the optical reproducing means based on the reproduced recording information. Signal generating means, first comparing means for detecting that the amplitude of the track displacement signal exceeds a voltage range of a predetermined first reference value, and a value of the track displacement signal corresponding to a predetermined second reference value. Comparing means for detecting whether the signal is positive or negative, a pulse generating means for outputting a pulse train having a predetermined period during the period of the output signal of the first comparing means, and a second comparing means. And a switching means for switching the pulse train of the above based on the output signal of, is characterized in that a stepping motor moving means.

As described above, according to the present invention, it is possible to apply a stepping motor to a carriage servo system by using a circuit having a simple and inexpensive structure, to have a high-precision positioning control performance and to perform a high-speed access operation. It is possible to provide an excellent optical disk device that can incorporate a large-mass optical pickup.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to the first to sixth aspects of the present invention is directed to an optical disk rotation driving means for mounting and rotating an optical disk and irradiating the optical disk from a light source with a reflected light. An optical disc device having an optical reproducing means for reproducing recorded information on an optical disc and a moving means for moving the optical reproducing means in a radial direction of the optical disc, wherein an information recording position of the optical disc is determined based on the reproduced recorded information. Track displacement signal generating means for generating an amount of displacement between the track displacement signal and the optical reproducing means; a first comparator for detecting that the amplitude of the track displacement signal exceeds a voltage range of a predetermined first reference value; A second comparator for detecting whether the value of the signal is positive or negative with respect to a predetermined second reference value, and a signal having a predetermined period during a period of the output signal of the first comparator. A pulse generating means for outputting a pulse train, and a switching means for switching the pulse train of the foregoing, is characterized in that a stepping motor moving means.

According to the present invention, it is possible to apply a stepping motor to a carriage servo system by using a circuit having a low cost and a simple structure. It is possible to provide an excellent optical disk device in which a pickup can be incorporated.

According to a seventh aspect of the present invention, there is provided an optical disk rotation driving means for mounting and rotating an optical disk and irradiating the optical disk with a light source from a light source and recording information on the optical disk based on the reflected light. Optical reproducing means for reproducing the data, first moving means for slightly moving the optical reproducing means in the radial direction of the optical disk, and optical reproducing means for moving beyond the moving range of the first moving means An optical disc drive having a second moving means for moving the optical disc in a radial direction of the optical disc, a track displacement signal generating means for generating a displacement between an information recording position of the optical disc and an optical reproducing means based on the recorded information; A first comparing means for detecting that the amplitude of the displacement exceeds a voltage range of a predetermined first reference value, and determining whether the value of the displacement is positive or negative with respect to the predetermined second reference value. A second comparing means for outputting a pulse train of a predetermined cycle during an output period of an output signal of the first comparing means, and a switching means for switching the pulse train. The means is characterized by using a stepping motor.

According to the present invention, it is possible to apply a stepping motor to a carriage servo system with a circuit having a low cost and a simple structure, to have a high-precision positioning control performance, to perform a high-speed access operation, and to realize a large-mass light It is possible to provide an excellent optical disk device that can incorporate a pickup and that uses servo control suitable for minute tracking movement and carriage movement.

An embodiment of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a block diagram of an optical disk apparatus according to an embodiment of the present invention. In FIG. 1, 1
Is an optical disk (CD-ROM), 2 is an optical pickup,
4, Objective lens (bobbin), 5 is spindle motor, 6
Is a screw shaft, 9 is an RF amplifier, 11, 17 and 20 are drivers, 13 is a controller, 14 is a signal processing circuit, 15 is a host IF, 16 is a host, 18 is a spindle motor control circuit, 19 is a focus servo circuit, 23 Is an equalizer, and 24 is an amplifier. These circuit components have the same functions as those of the conventional components, and are denoted by the same names and the same reference numerals to omit redundant description.

The differences from the prior art are that there is no gear 7, that a stepping motor 27 is used instead of the DC motor 8, and that a driver 29 for driving the stepping motor 27 is used instead of the driver 10 for driving the DC motor 8. (See FIG. 2) and a tracking servo circuit 28 for a stepping motor 27 in place of the tracking servo circuit 12 for the DC motor 8.

Further, the tracking servo circuit 28 for the stepping motor 27 is
8A and a stepping motor control unit 28B. The tracking coil control unit 28A includes an equalizer 23 for controlling the tracking coil and an amplifier 24 for amplifying the control signal of the tracking coil, as in the related art.
Having.

FIG. 2 is a detailed block diagram of the stepping motor control unit 28B in FIG. In FIG. 2, reference numeral 13 denotes a controller. 26 is an equalizer for controlling the stepping motor 27, and 29 is a driver for driving the stepping motor 27. Reference numeral 30 denotes a comparator having two types of functions, reference numeral 31 denotes a window comparator, and reference numeral 33 denotes a rotation direction control comparator. 32 is a pulse generation circuit, and 34 is a switching circuit.

The operation of the optical disk (CD-ROM) driving device according to the embodiment of the present invention will be described below with reference to FIG.

The information recorded on the optical disk 1 is reproduced by the optical pickup 2, and the output signal of the optical pickup 2 is R
The signal is amplified by the F amplifier 9 and supplied to the signal processing circuit 14 as an information signal. The controller 13 is a signal processing circuit 1
A torque command signal is output to the spindle motor control circuit 18 based on the information signal of (4). Thus, the spindle motor 5 is driven by the spindle motor 5 via the driver 17 for the spindle motor.
LV (constant linear velocity) control is performed.

The output signal of the optical pickup 2 is converted to an RF signal.
Based on the information signal amplified by the amplifier 9, an FE (focus error) signal, a TE (tracking error) signal, an RF (information) signal, and the like are generated. The FE signal is subjected to signal processing by a focus servo circuit 19 and output to a focus control driver 20. The focus actuator (not shown) outputs the objective lens 4.
Is driven in the focus direction (vertical direction of the optical disc 1).

The TE signal is input to the tracking servo circuit 28. The tracking servo circuit 28 includes a tracking coil 21 provided in the optical pickup 2.
Tracking coil controller 28 (see FIG. 6)
A and a stepping motor control unit 28B for controlling the stepping motor 28.

The tracking coil control unit 28A includes a tracking coil control equalizer 23 that generates a waveform signal sufficient to control the objective lens 4 to move minutely in the tracking direction (disc radial direction), and adds a required gain to the waveform. A tracking coil control signal amplifying amplifier 24 that gives a moderate movement of the objective lens 4 when given. This configuration is the same as the conventional one and is not the subject of the present invention.

On the other hand, in FIG. 2, the stepping motor control unit 28 B controls the carriage 3 (see FIG. 6) with a screw in order to cover a range in which the information track of the optical disc 1 cannot be completely followed by the minute movement of the objective lens 4. A control signal for performing movement control by rotation of the shaft 6 is generated.

Further, since the stepping motor 27 has a high torque characteristic, the screw shaft 6 can be directly driven. As a result, the gear portion (corresponding to the gear 7 in FIG. 5) can be eliminated, so that the number of constituent parts can be reduced.

The equalizer 26 for controlling the stepping motor 27 is for generating an SE signal required for coarse movement control of the carriage 3 (see FIG. 6), and has a function of extracting a low frequency component of the TE signal.

The comparator 30 is a stepping motor 2
7 generates a signal for controlling the rotation start, stop, and rotation direction of the motor 7, and includes a window comparator 31 and a rotation direction control comparator 33. The window comparator 31 generates an on / off signal for controlling the start and stop of the rotation of the stepping motor 27, and generates a switching circuit 34.
Output to At the same time, the on / off signal also has a function as a request signal for causing the pulse generation circuit 32 to generate a pulse. The window comparator 31 uses the aforementioned S
The E signal is compared with the reference value 1 and output when the absolute value of the SE signal exceeds the reference value 1. The reference value 1 is set from outside (for example, DA conversion of a controller output) and is supplied as a variable voltage value ± Vth having a required voltage width centered on 0 (zero).

The rotation direction control comparator 33 generates a CW / CCW signal for controlling the rotation direction of the stepping motor 27 and supplies it to the switching circuit 34. The rotation direction control comparator 33 is composed of a general comparator. The rotation direction control comparator 33 compares the above-mentioned SE signal with the reference value 2 and outputs the result. The reference value 2 is set from outside (for example, DA conversion of the controller output), and is usually set to 0V. Therefore, the rotation direction control comparator 33 has the SE
It functions as a zero-crossing detector of the signal, and generates a binary signal according to the zero-crossing of the SE signal.

The pulse generation circuit 32 requests a pulse from the window comparator 31 (ie, the period of the output signal).
The pulse signal is generated by a general known pulse oscillation circuit using an operational amplifier, a comparator and the like. The rotation angle position of the stepping motor 27 can be easily controlled by the number of pulses from the pulse generation circuit 32. For example, CD-R
In the case of the standard speed of OM, the optical disk 1 is 200 to 500 r
Rotate at about pm. Since the track pitch of the CD-ROM is 1.6 μm, the track is 320 μm / min to 8 μm.
It apparently moves at a speed of 00 μm / min.

Therefore, in order for the optical pickup to follow the track, the pulse rate of the pulse generating circuit 32 may be selected so that the moving speed of the carriage is about 1 mm / min. This allows efficient control of the motor without rotating the motor more than necessary.

Note that this pulse rate is not only set to keep the moving speed of the carriage constant as in this embodiment, but also, for example, the pulse rate is increased or decreased according to the magnitude of the SE signal. The oscillation frequency of the oscillation circuit 32 may be variably controlled. In this case, the moving speed of the carriage can be set according to the magnitude of the seek error (SE signal).

The switching circuit 34 is connected to the controller 1
The switching between the sequential read operation and the access operation is performed by the switching signal from the controller 3.
By giving an on / off signal, a pulse signal, and a CW / CCW signal from the controller 13 to the controller 9, high-precision movement control is possible.

FIG. 3 is a signal waveform diagram of each block in FIG. The dotted lines connecting the upper and lower sides in the figure represent the same timing. 3, (A) is a waveform diagram of the SE signal, (B) is a waveform diagram of the output signal of the window comparator 31, and (C) is an output CW of the rotation direction control comparator 33.
/ CW signal waveform diagram, (D) is a window comparator 31
4E is a waveform diagram of an output signal of the pulse generation circuit 32 that generates a pulse signal in response to the pulse request. FIG. 4E is a diagram showing the displacement (rotational movement) of the stepping motor 27 driven by the driver 29.

FIG. 3 shows waveforms when the optical pickup 2 continuously follows information tracks on the rotating optical disk 1 (sequential read). The voltage value ± Vth in FIG. 3A indicates an upper limit value and a lower limit value of the reference value 1, and these two values can be freely set from outside. When the SE signal exceeds the upper limit and the lower limit, the window comparator 31 outputs an on / off control signal shown in FIG. Window comparator 31
Is composed of a comparator having a comparison width by a combination of a comparator IC or the like and a resistor according to a known technique.

On the other hand, FIG. 3C shows an output signal when the reference value 2 of the rotation direction control comparator 33 is set to the potential 0 (zero). When the SE signal crosses the reference value 2, the output of the rotation direction control comparator 33 is inverted. In the example shown in the drawing, the output of the SE signal outputs a high high potential when the SE signal is positive, and outputs a low potential when the SE signal is negative. This High, Low
The rotation direction is controlled by relating the two signals to the rotation direction.

FIG. 3D shows a pulse output waveform of the pulse generation circuit 32, and a pulse signal is generated by an on / off control signal based on the output of the window comparator 31. The rotation angle (rotation amount) of the stepping motor 27 can be easily controlled by the number of pulses of the pulse generation circuit 32.

FIG. 3E shows the amount of rotational movement of the stepping motor 27, which is related to the high and low rotational direction signals in FIG. 3C and is proportional to the number of pulses in FIG. 3D. It is possible to know the increase or decrease of the movement amount.

As described above, according to the present invention, it is shown that the carriage servo system has sufficiently high positioning control performance. Note that the SE signal in the negative region in FIG. 3A is an example of a state in which the carriage 3 is overrun for some reason for the present description. Even in this case, it can be seen that the stepping motor 27 is properly controlled and the SE signal is controlled so as to be focused around 0 (zero).

As described above, the on / off signal and the rotation direction signal are generated based on the TE signal, the pulse rate of the stepping motor 27 is generated from the on / off signal, and the supply order of the pulses is controlled from the rotation direction signal. The rotation speed and forward / reverse rotation of the stepping motor are controlled by the pulse rate and the supply order, and the moving speed and moving direction of the carriage are controlled.

As described above, the optical pickup 2 is controlled to follow the information track of the optical disk 1, and the information signal can be reproduced. The information signal is subjected to demodulation, error correction, and the like by the signal processing circuit 14 to become valid data, and is sent to the host 16 via the host IF 15. The controller 13 controls the operation of each of these blocks.

In this description, the pulse generation circuit 3
Although the pulse rate of No. 2 has been described as being constant, it is added that varying the pulse rate in accordance with the SE signal level is an application form easily derived from the present invention as described above.

Further, in the embodiment of the present invention, an example using the tracking coil control unit 28A and the stepping motor control unit 28B has been described. However, by reducing the reference value 1 to a value corresponding to the dead zone of the stepping motor, the stepping motor control unit 28B also has the function of the tracking coil control unit 28A, and the tracking coil control unit 28A as well as the driver 11 for the tracking coil and the tracking coil The coil 21 can be omitted. FIG. 4 shows a block diagram of the optical disk device in which the tracking coil 21 is omitted. FIG.
The difference from the above is that the tracking coil driver 11, the tracking coil 21, and the tracking coil control unit 28A are omitted as described above. As a result, the number of components can be reduced, cost can be reduced, the tracking coil 21 and the corresponding magnet can be omitted, and the pickup gap and peripheral components can be reduced in size and weight.

[0054]

As described above, according to the present invention, it is possible to apply a stepping motor to a carriage servo system by using a circuit having a simple and inexpensive structure, thereby achieving high-precision positioning control performance and high-speed access operation. Thus, it is possible to provide an excellent optical disk device which can incorporate a large-mass optical pickup.

[Brief description of the drawings]

FIG. 1 is a block diagram of an optical disk device according to an embodiment of the present invention.

FIG. 2 is a detailed block diagram of a stepping motor control unit in FIG. 1;

FIG. 3 is a signal waveform diagram of each block in FIG. 2;

FIG. 4 is a block diagram of an optical disc device according to another embodiment of the present invention.

FIG. 5 is a configuration diagram of a conventional optical disk drive.

FIG. 6 is a configuration diagram of an optical pickup.

FIG. 7 is a configuration diagram of the tracking servo circuit of FIG. 5;

[Explanation of symbols]

 Reference Signs List 1 optical disk (CD-ROM) 2 optical pickup 3 carriage 4 objective lens (bobbin) 5 spindle motor 6 screw shaft 7 gear 8 DC motor (feed motor) 9 RF amplifier 10, 11, 17, 20, 29 driver 12, 28 tracking Servo circuit 13 Controller 14 Signal processing circuit 15 Host IF 16 Host 18 Spindle motor control circuit 19 Focus servo circuit 21 Tracking coil 22 Magnet 23, 26 Equalizer 24, 25 Amplifier 27 Stepping motor 28A Tracking coil control unit 28B Stepping motor control unit 30 Comparator 31 Window Comparator 32 Pulse Generation Circuit 33 Rotation Direction Control Comparator 34 Switching Circuit

Claims (9)

[Claims] An optical disk rotation driving step of driving the optical disk to rotate; an optical reproduction step of irradiating the optical disk from a light source to reproduce information recorded on the optical disk based on reflected light; and setting an information reproduction position in a radial direction of the optical disk. An optical disc driving method having a moving step of moving, wherein a track displacement signal generating step of generating a displacement amount between a recording information position of the optical disc and the information reproducing position based on the recording information; A first comparing and detecting step for detecting that the voltage range of a predetermined first reference value has been exceeded, and a second comparing and detecting whether the value of the displacement amount is positive or negative with respect to a predetermined second reference value A pulse train generating step of outputting a pulse train having a predetermined cycle during a detection period of the first comparison and detection step; An optical disk driving method, comprising: a switching step of switching a row of disks; wherein the moving step is performed by using a stepping motor in the moving step. 2. The optical disc driving method according to claim 1, wherein the switching step switches the pulse sequence of the pulse train based on a detection result of the second comparison detection step. 3. The method according to claim 1, wherein the switching step includes: a pulse train having a predetermined cycle obtained in the pulse train generating step, a detection result of the second comparison detection step, a pulse train having a cycle separately determined from the outside, and a rotation direction. 2. The optical disk drive method according to claim 1, wherein the signal is switched. 4. An optical disk rotation driving means for mounting and rotating an optical disk, an optical reproduction means for irradiating the optical disk from a light source and reproducing recorded information on the optical disk based on the reflected light, and the optical reproduction means A moving means for moving the optical disc in a radial direction of the optical disc, a track displacement signal generating means for generating a displacement between an information recording position of the optical disc and the optical reproducing means based on the recording information. First comparing means for detecting that the amplitude of the displacement exceeds a voltage range of a predetermined first reference value; and determining whether the value of the displacement is positive with respect to the predetermined second reference value. A second comparing means for detecting whether the signal is negative, a pulse train generating means for outputting a pulse train having a predetermined cycle during an output period of the output signal of the first comparing means, and an output of the second comparing means. Switching means for switching the pulse train based on a signal, wherein the moving means uses a stepping motor. 5. The optical disk apparatus according to claim 4, wherein said switching means switches the pulse sequence of said pulse train based on a detection result of said second comparing means. 6. The switching means comprises: a pulse train having a predetermined cycle obtained by the pulse train generating means and a detection result of the second comparing means; a pulse train having a cycle separately determined from the outside; and a rotation direction signal. 5. The optical disk device according to claim 4, wherein the optical disk device is switched between 7. An optical disk rotation drive means for mounting and rotating an optical disk, an optical reproduction means for irradiating the optical disk from a light source, and reproducing recorded information on the optical disk based on the reflected light, and the optical reproduction means First moving means for slightly moving the optical disc in the radial direction of the optical disc; and second moving means for moving the optical reproducing means in the radial direction of the optical disc when the optical reproducing means is moved beyond the moving range of the first moving means. An optical disc device having: a track displacement signal generating means for generating a displacement between an information recording position of an optical disc and the optical reproducing means based on the recording information; and an amplitude of the displacement being predetermined. A first comparing means for detecting that the voltage range of the first reference value has been exceeded, and a second comparing means for detecting whether the value of the displacement amount is positive or negative with respect to a predetermined second reference value. Comparing means, a pulse train generating means for outputting a pulse train having a predetermined period during the output period of the output signal of the first comparing means, and switching for switching the pulse train based on the output signal of the second comparing means And an optical disk device, wherein the second moving means uses a stepping motor. 8. The optical disk apparatus according to claim 7, wherein said switching means switches the pulse sequence of said pulse train based on a detection result of said second comparing means. 9. The switching means comprises: a pulse train having a predetermined cycle obtained by the pulse train generating means and a detection result of the second comparing means; a pulse train having a cycle separately determined from the outside; and a rotation direction signal. 8. The optical disk device according to claim 7, wherein the optical disk device is switched between and.