JP2732590B2 - Recording medium processing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a recording medium processing device such as a disk device for recording or reproducing information on an optical disk, for example.

2. Description of the Related Art As is well known, various disk devices have been developed which record information on an optical disk or read information recorded on an optical disk by using a laser beam output from a semiconductor laser, for example.

In such an optical disk device, an optical system including a semiconductor laser that generates laser light, an objective lens that focuses laser light from the semiconductor laser on an optical disk, and a photodetector that detects reflected light from the optical disk is used. Have. Then, laser light emitted from a semiconductor laser in the optical system is condensed by an objective lens and irradiates a target track on an optical disk, whereby recording or reproduction is performed.

When moving the laser beam to a target track (track access) for such recording or reproduction, the entire optical system is moved by, for example, a linear motor for coarse access, and a spring or the like is used. The objective lens supported so as to be movable in the track direction is moved by a lens actuator to perform precise access, thereby moving to the target track.

In the precision access, a constant acceleration current is applied to the lens actuator while counting the number of laser beams converged by the objective lens traversing the track,
When a predetermined number is counted, a constant deceleration current is applied to move to a target track against a spring force while accelerating and decelerating.

However, in the recording medium processing device as described above,
Since the moving speed of the objective lens (condensing means) is controlled only by a constant acceleration current and a constant deceleration current, when jumping a large number of tracks, it cannot completely withstand the repulsive force of the spring whose displacement has increased, There are drawbacks in that it is not possible to jump to the target track, or the track-on after the jump is not stable.

(Problems to be Solved by the Invention) According to the present invention, as described above, when the moving speed is controlled only by the constant acceleration current and the constant deceleration current, the displacement amount becomes large when jumping a large number of tracks. It eliminates the drawbacks that it cannot withstand the repulsive force of the elastically supported light-collecting means and cannot jump to the target track, or the track-on after the jump is not stable. It is an object of the present invention to provide a recording medium processing apparatus capable of performing a track jump accurately and stably even when a large number of tracks are jumped by an objective lens as optical means.

The present invention relates to a recording medium processing apparatus that records information on a recording medium having a recording track or reproduces information recorded on the recording medium. A light beam generating means for generating a light beam, and condensing the light beam from the light beam generating means on the recording medium by using a condensing means, or detecting the light beam reflected from the recording medium. An optical head comprising a detecting means for outputting a signal; and a light collecting means in the optical head elastically supported, and the light collecting means is moved in a direction orthogonal to a recording track direction of the recording medium. A first moving unit, a second moving unit that supports the optical head, and moves the optical head in a direction orthogonal to a recording track direction of the recording medium, and a collection of the optical head. When the track difference between the recording track of the recording medium irradiated with the light beam by the means and the recording track to be accessed is equal to or more than a predetermined number of tracks, the access is performed by moving the optical head by the second moving means. When the track difference is equal to or less than a predetermined number of tracks, the first moving means moves the light collecting means to access the light collecting means, and the first moving means moves the light collecting means. First accelerating means for generating an accelerating / decelerating current, and when the light condensing means is moved by the first moving means,
Counting means for counting the number of traversing recording tracks of the recording medium, and a drive for generating a force balanced with the elastic force of the first moving means caused by the movement of the light condensing means based on the counting result of the counting means. A second generator for generating a current, an acceleration / deceleration current generated by the first generator, and a drive current generated by the second generator are added;
And control means for controlling the movement of the light collecting means by the first moving means.

The present invention relates to a light beam generating means for generating a light beam in a recording medium processing device for recording information on a recording medium having a recording track or reproducing information recorded on the recording medium, An optical head comprising output means for converging the light beam from the beam generating means on the recording medium using the condensing means, and outputting a detection signal for the light beam reflected from the recording medium; and A first moving means for elastically supporting the light collecting means in the optical head, moving the light collecting means in a direction orthogonal to the direction of the recording track of the recording medium, and supporting the optical head; Second moving means for moving the optical head in a direction perpendicular to the direction of the recording track of the recording medium, and a recording medium irradiated with a light beam by the condensing means of the optical head When the track difference between the recording track and the recording track to be accessed is equal to or more than a predetermined number of tracks, access is performed by moving the optical head by the second moving means, and when the track difference is equal to or less than the predetermined number of tracks. Processing means for performing an access by moving the light condensing means by the first moving means, and accelerating / decelerating pulse generation for generating an accelerating / decelerating pulse for moving the light converging means by the first moving means. A circuit, a track counting circuit for counting the number of recording tracks traversing the recording track of the recording medium when the light condensing means is moved by the first moving means, A conversion circuit for converting into a drive signal for generating a force balanced with the elastic force of the first moving means generated by the movement of the means; Adding the drive circuit is converted by the deceleration pulse and the conversion circuit generated by the pulse generating circuit, and a control circuit for controlling the movement of said focusing means by said first mobile unit.

(Operation) The present invention provides a light beam generating means for generating a light beam in a device for recording information on a recording medium having a recording track or reproducing information recorded on the recording medium, An optical head comprising: a light beam from the beam generating means; and a detecting means for condensing the light beam on the recording medium using the condensing means, and outputting a detection signal for the light beam reflected from the recording medium. A first moving means for elastically supporting the light collecting means in the optical head, moving the light collecting means in a direction orthogonal to the direction of the recording track of the recording medium, and supporting the optical head; Second moving means for moving the optical head in a direction perpendicular to the direction of the recording track of the recording medium, and recording of the recording medium irradiated with a light beam by the condensing means of the optical head. When the track difference between the recording track and the recording track to be accessed is equal to or more than a predetermined number of tracks, access is performed by moving the optical head by the second moving means, and when the track difference is equal to or less than the predetermined number of tracks. Processing means for performing access by moving the light collecting means by the first moving means, and accelerating and decelerating current for moving the light collecting means by the first moving means to the first When the light collecting means is moved by the first moving means, the number crossing the recording track of the recording medium is counted by the counting means, and the collecting result is calculated by the counting means. The second generator generates a drive current that generates a force that balances the elastic force of the first mover generated by the movement of the optical unit, and the drive current generated by the first generator is generated. The sum of the drive current generated by the fast current and said second generating means, in which so as to control the movement of the focusing means according to the first moving means.

The present invention relates to a light beam generating means for generating a light beam in recording information on a recording medium having a recording track or reproducing information recorded on the recording medium, and the light beam generating means. An optical head comprising: a light beam from the optical disc; and a detecting means for outputting a detection signal for the light beam reflected from the recording medium by using a condensing means. First moving means for elastically supporting the light collecting means in the head and moving the light collecting means in a direction orthogonal to the direction of the recording track of the recording medium; and supporting the optical head; Second moving means for moving the recording medium in a direction orthogonal to the direction of the recording track of the recording medium; and a recording track of the recording medium irradiated with the light beam by the condensing means of the optical head. When the track difference from the recording track to be accessed is equal to or more than a predetermined number of tracks, access is performed by moving the optical head by the second moving means. Processing means for performing access by moving the light condensing means by means of a first moving means, and an acceleration / deceleration pulse generating circuit for accelerating and decelerating pulses for moving the light condensing means by means of the first moving means When the light condensing means is moved by the first moving means, the number of the recording medium crossing the recording track is counted by a track counting circuit, and the count value of the track counting circuit is calculated by the collecting means. The conversion circuit converts the driving signal into a drive signal for generating a force that balances the elastic force of the first moving means generated by the movement of the light means, and generates the acceleration / deceleration pulse. Adding the drive circuit to be converted in deceleration pulse and the conversion circuit generated by the road, in which so as to control the movement of the focusing means according to the first moving means.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 3 shows a disk device to which the recording medium processing device according to the present invention is applied. On the surface of the optical disk (recording medium) 1, grooves (tracks) are formed in a spiral or concentric manner.
The motor 2 rotates at a constant speed, for example. The motor 2 is controlled by a motor control circuit 18.

As shown in FIG. 4, the optical disc 1 has a doughnut-shaped metal film layer such as tellurium or bismuth, that is, a recording film, coated on the surface of a substrate formed in a circular shape with glass or plastics, for example.
A notch, that is, a reference position mark 39 is provided near the center of the metal coating layer.

On the optical disk 1, as shown in FIG. 4, the reference position mark 39 is "0" and divided into 256 sectors "0 to 255". Variable length information is recorded over a plurality of blocks on the optical disc 1, and 300,000 blocks are formed on 36,000 tracks on the optical disc 1.

The number of sectors of one block on the optical disc 1 is, for example, 40 sectors on the inner side and 20 sectors on the outer side. At the start position of the block, a block header A including a track number, a sector number, and the like is recorded, for example, when the optical disc 1 is manufactured.

If each block on the optical disc 1 does not end at the sector switching position, a block gap is provided so that each block always starts from the sector switching position.

Recording and reproduction of information on the optical disk 1 are performed by an optical head 3, as shown in FIG. The optical head 3 is fixed to a drive coil 13 constituting a movable portion of a linear motor, and the drive coil 13 is connected to a linear motor control circuit 17.

A linear motor position detector 26 is connected to the linear motor control circuit 17, and the linear motor position detector 26 detects the optical scale 25 provided on the optical head 3 to generate a current position signal. Output.

Further, a permanent magnet (not shown) is provided at the fixed portion of the linear motor, and the optical head 3 moves in the radial direction of the optical disc 1 by exciting the drive coil 13 by the linear motor control circuit 17 (see FIG. (Coarse access).

As shown in FIG. 5, an objective lens 6 is supported on the optical head 3 by a wire or a leaf spring (elastic member) 4a. The objective lens 6 is moved by a driving coil 5 in a focusing direction (light of the lens). (In the axial direction), and is moved in the tracking direction (the direction of arrow AB perpendicular to the optical axis of the lens) by a drive coil (lens actuator coil) 4 as a moving means.

The laser light generated by the semiconductor laser 9 driven by the laser control circuit 14
a, the light is irradiated onto the optical disc 1 through the half prism 11b and the objective lens 6, and the reflected light from the optical disc 1 is
The light is guided to the photodetector 8 via the objective lens 6, the half prism 11b, the condenser lens 10a, and the cylindrical lens 10b. The photodetector 8 includes four divided photodetection cells 8a and 8a.
b, 8c and 8d.

The output signal of the photodetector cell 8a of the photodetector 8 is an amplifier.
The output signal of the photodetection cell 8b is supplied to one end of the adders 30a and 30c via the
d, the output signal of the photodetection cell 8c is supplied to the other end of the adders 30b and 30c via the amplifier 12c, and the output signal of the photodetection cell 8d is supplied to the adder 30a via the amplifier 12d. ,
The other end of 30b is supplied.

The output signal of the adder 30a is supplied to the inverting input terminal of the differential amplifier OP1, and the output signal of the adder 30b is supplied to the non-inverting input terminal of the differential amplifier OP1. This allows
The differential amplifier OP1 supplies a track difference signal a to the tracking control circuit 16 according to the difference between the adders 30a and 30b. This tracking control circuit 16
A track drive signal is generated in accordance with the track difference signal a supplied from the controller, and will be described later in detail.

The track drive signal output from the tracking control circuit 16 is supplied to the drive coil 4 in the tracking direction, and the beam light is moved by moving the objective lens 6 according to the number of tracks to be jumped. I have. The track difference signal a used in the tracking control circuit 16 is also supplied to a linear motor control circuit 17.

The output signal of the adder 30c is supplied to the inverting input terminal of the differential amplifier OP2, and the output signal of the adder 30d is supplied to the non-inverting input terminal of the differential amplifier OP2. As a result, the differential amplifier OP2 supplies a signal relating to the focus point to the focusing control circuit 15 according to the difference between the adders 30c and 30d. The output signal of the focusing control circuit 15 is
And the laser light is controlled so that it is always just focused on the optical disc 1.

The sum signal of the outputs of the photodetection cells 8a, 8d of the photodetector 8 in the state where the focusing and tracking are performed as described above, that is, the output signals from the adders 30a, 30b are formed on the track. The unevenness of the pits (recorded information) is reflected. This signal is supplied to the video circuit 19, where the image information and address information (track number, sector number, etc.) are reproduced.

The laser control circuit 14, the focusing control circuit 15,
The tracking control circuit 16, the linear motor control circuit 17, the motor control circuit 18, the video circuit 19, and the like are controlled by a CPU 23 via a bus line 20.
Reference numeral 23 performs a predetermined operation according to a program stored in the memory 24.

The D / A converter 22 is used for exchanging information between the focusing control circuit 15, the linear motor control circuit 17 and the CPU 23.

The tracking control circuit 16 is configured as shown in FIG. That is, the switch SW01 is connected to the CPU 2
The tracking servo loop is turned on and off by turning on and off in response to a control signal transmitted from 3 through the control unit 51. The phase compensation circuit 40 is a well-known circuit that compensates for the advance or delay of the phase of the track difference signal a supplied from the OP1. A track difference signal (track tracking signal) supplied from the phase compensation circuit 40 is supplied to an adder 41 via an amplifier as a drive circuit.
Predetermined amplification is performed by 42, and the objective lens 6 is moved by driving the drive coil 4. These form a tracking servo loop by feedback control.

Further, the track pulse generating circuit 43 in the tracking control circuit 16 binarizes the track difference signal a by comparing it with a predetermined voltage. That is, the state in which the objective lens 6 is moving appears as a signal change on the track difference signal a when the light beam traverses the track, and is binarized to obtain a track pulse corresponding to the number of traversed tracks. Is obtained. The output of the track pulse generating circuit 43 is supplied to a track counting circuit 44, where the track pulse is counted so that the moving distance of the track can be obtained. This track count circuit 44
Are sent to the control unit 51, while the control unit 51 sets an arbitrary value.

The D / A converter 45 converts the binary data held by the track count circuit 44 into an analog signal, and
It is sent to 50. The 1/2 count detection circuit 46
The number of tracks to be jumped given by the control unit 51 is compared with the content of the track count circuit 44, and when the content of the track count circuit 44 becomes half of the number of tracks to be jumped, a signal indicating that fact is added. Deceleration pulse generation circuit
Output to 49. The full count detection circuit 47
The number of tracks to be jumped is compared with the contents of the track count circuit 44, and when the contents of the track count circuit 44 become equal to the number of tracks to be jumped, a signal indicating the fact is output to the acceleration / deceleration pulse generation circuit 49. Is what you do. In addition, the speed detection circuit 48 includes a track count circuit 44
The speed at which the light beam crosses the track is detected by measuring the time for counting up, that is, the generation interval of the track pulse.

The acceleration / deceleration pulse generating circuit 49 generates an acceleration / deceleration pulse b as shown in FIG. 2 (b). That is, an acceleration pulse (first half) is generated by a control signal from the control unit 51, and is changed to a deceleration pulse (second half) according to the detection signal from the 1/2 count detection circuit 46, and the detection from the full count detection circuit 47 is performed. Acceleration / deceleration pulse b by signal
This is the end of the output. The output of the acceleration / deceleration pulse generation circuit 49 is sent to the adder 50, and is added to the output of the D / A converter 45.

The output of the adder 50 is supplied to the adder 41 via a switch SW02 which is turned on / off according to a control signal from a control unit 51.
To be sent.

Further, the control section 51 plays a role of an interface with the CPU 23 and also performs various controls inside the tracking control circuit 16.

Next, a track access operation in such a configuration will be described. For example, a block number to be accessed is supplied to the CPU 23 from an external device (not shown). Then, the CPU 23 calculates a track number and a start sector number to be accessed using a table (not shown) based on the block number. Then, the CPU 23 determines the current position based on the track number and the sector number as the address information supplied from the video circuit 19 (the contents of the block header A of the track to which the light beam from the optical head 3 currently corresponds). At this time, if the optical head 3, that is, the track corresponding to the light beam is located at the target track (moving position), the access ends.

If there is a difference between the track supported by the optical head 3 and the target track, the CPU 23 determines the difference (track difference) and direction (inward,
Outside). Based on the result of this calculation, the CPU 23 determines whether the moving distance is a long distance (more than 50 tracks) or a short distance (50 tracks).
(Less than the number of tracks). If the result of this determination is a long distance, coarse access is performed by a linear motor, and if the result is a short distance, precise access is performed by a lens actuator.

Hereinafter, the precise access operation of the recording medium processing apparatus will be described. In a normal tracking operation, the switch SW01 is turned on (closed) and the switch SW02 is turned off (open) to form a tracking servo loop, and the combined tracking state is maintained by performing feedback control. Here, when it is determined that the track jumps to a short distance based on the calculation result, the control unit 51 switches the switch SW01.
Is turned off (open), switch SW02 is turned on (closed), and the tracking servo loop is opened. Then, the count value of the track count circuit 44 is cleared to zero. Next, by sending a control signal to the acceleration / deceleration pulse generating circuit 49, an acceleration / deceleration pulse b as shown in FIG. 2 (b) is generated. The acceleration / deceleration pulse (acceleration portion) b is input to one input terminal of the adder 50. On the other hand, since the track count circuit 44 holds zero as the counter value, D / A
The output c of the converter 45, that is, the other input of the adder 50 is zero, and the acceleration / deceleration pulse b is sent to the amplifier 42 via the switch SW02 and the adder 41 as it is. At this time, since the switch SW01 is turned off, there is no output from the phase compensation circuit 40, and the acceleration / deceleration pulse b is input to the amplifier 42 as it is. Then, after predetermined amplification is performed by the amplifier 42, the signal is output as a drive signal d. As a result, a current flows through the drive coil 4, and the objective lens 6 starts moving toward the target track.

A detection signal is output from the photodetector 8 by the start of the movement, and the differential amplifier OP is output through the adders 30a and 30b shown in FIG.
Supplied to 1. The differential amplifier OP1 generates a track difference signal a (see FIG. 2A) based on the signal obtained from the photodetector 8, and outputs the signal to the track pulse generation circuit 43 in the tracking control circuit 16. As a result, the track difference signal a is binarized in the track pulse generation circuit 43, and the binarized pulse is counted by the track count circuit 44.

The output from the track count circuit 44 is converted to an analog signal by the D / A converter 45 and is provided to the other input of the adder 50.

As shown in FIG. 2C, the output c of the D / A converter 45 increases as the count value of the track count circuit 44 increases, that is, as the number of tracks traversed by the objective lens 6 increases. . This means that a voltage corresponding to the moving distance of the objective lens is output.

That is, as the moving distance of the objective lens 6, that is, the displacement increases, a force toward the center (equilibrium point) acts on the spring 4a supporting the objective lens 6 (so-called F).
= -Kx). Therefore, even if a voltage of a certain level such as the acceleration / deceleration pulse b is continuously applied and the motor is moved, the motor will stall. Here, as shown in FIG. 6, since the displacement of the spring 4a is proportional to the current applied to the driving coil 4, the output of the D / A converter 45 corresponding to the displacement of the spring 4a is gradually increased to increase the spring. By generating drive power that offsets the force toward the center of 4a, it is possible to keep giving an apparently constant acceleration. The D / A converter 45 is
A voltage for giving such an acceleration is generated.

In this way, the addition of the acceleration / deceleration pulse b from the acceleration / deceleration pulse generation circuit 49 and the output signal c of the D / A converter 45 by the adder 50 becomes the drive signal d of the objective lens 6 and the objective lens 6 6 moves while being accelerated.

The movement of the objective lens 6 proceeds, and the 1/2 count detection circuit 46
When it is detected that the count value of the track count circuit 44 has reached half of the number of tracks to be jumped, a signal indicating that fact is output to the acceleration / deceleration pulse generation circuit 49. As a result, the acceleration / deceleration pulse generation circuit 49
As shown in FIG. 7B, the acceleration / deceleration pulse b is changed to deceleration (the latter half). At this time, the output signal c of the D / A converter 45
In the same manner as described above, the result obtained by adding the acceleration / deceleration pulse b from the acceleration / deceleration pulse generation circuit 49 and the output signal c of the D / A converter 45 by the adder 50 is The driving signal becomes d, and the objective lens 6 moves while being decelerated.

Thus, the moving speed of the objective lens 6 decreases,
When the full count detection circuit 47 detects that the count value of the track count circuit 44 has become the same as the number of tracks to be jumped, it outputs an access end signal to that effect to the acceleration / deceleration pulse generation circuit 49. Output to 51. As a result, the acceleration / deceleration pulse generation circuit 49
Sets the output of the acceleration / deceleration pulse b to zero as shown in FIG. 2 (b).

The control unit 51 that has received the access end signal outputs a control signal, turns on the switch SW01, connects the tracking servo loop, and enters a normal tracking operation. At this time, since the objective lens 6 is out of the equilibrium point, the objective lens 6 tries to return to the center of the actuator off the track by the spring force. Therefore, immediately after the acceleration / deceleration pulse becomes zero (immediately after the track is turned on), there is a tendency for instability. However, D / A converter 45
Keeps the output corresponding to the count value of the track count circuit 44, thereby maintaining a balance with the spring force. The tracking operation is performed in a state where the balance is maintained, and it is detected that the tracking is stable by detecting that the track count circuit 44 has not counted up for a certain time t, for example, 1 to 20 milliseconds. And then switch SW02
Is turned off, and the application of the voltage from the D / A converter 45 is stopped. Thereafter, the objective lens 6 is maintained on the target track by normal tracking servo, and recording or reproduction is performed.

As described above, a drive current that balances the spring force generated in accordance with the displacement of the objective lens is generated in accordance with the number of tracks traversed by the objective lens 6, and is superimposed on the acceleration / deceleration pulses to drive the lens actuator. As a result, stable track access can be performed.

The end of the track access is detected based on the number of traversed tracks by the full count detection circuit 47.
Alternatively, the determination may be made by detecting that the moving speed has become sufficiently slow. In this case, the same effect as described above is produced.

Also, the 1/2 count detection circuit 46 shown in the above embodiment,
The full count detection circuit 47, the speed detection circuit 48, and the acceleration / deceleration pulse generation circuit 49 can be configured to be performed by the processing of the control unit 51. A block diagram of the circuit configuration in this case is shown in FIG. 7, and a processing flowchart is shown in FIG.

In FIG. 7, the same parts as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted. The control unit 52 is configured by, for example, a microcomputer or the like. Also, D /
The A converter 53 is directly driven by the control unit 52 and the switch S
The driving coil 4 is driven via W02 and the amplifier 42.

The processing of the control unit 52 will be described with reference to FIG. Similarly to the above, when it is determined that a jump to a short distance is made based on the calculation result, the track counter in the track counter circuit 44 is cleared (step S1). Then
Turn off switch SW01 (open), turn on switch SW02 (closed)
(Step S2) to release the tracking servo loop. Next, by sending a control signal to the D / A converter 53, an acceleration / deceleration pulse b as a drive pulse as shown in FIG. 2 (b) is generated (step S3). Then, the track counter is read (step S4), and it is checked whether 3/4 of the specified number of tracks to be jumped has been passed (step S5). Is checked (step S6). here,
If it has not exceeded 1/2, the value obtained by multiplying the value of the track counter by a predetermined coefficient A (a value for generating a voltage for canceling the force of the displaced spring 4a toward the center) and the drive pulse (acceleration / deceleration) Pulse), and outputs the result to the D / A converter 53 (step S7). The output of the D / A converter 53 is supplied to an amplifier 42 via a switch SW02 and an adder 41.
Sent to At this time, since the switch SW01 is turned off, there is no output from the phase compensation circuit 40, and the amplifier 42
The output of the D / A converter 53 is supplied as it is. Then, after predetermined amplification is performed by the amplifier 42, the signal is output as a drive signal d. As a result, a current flows through the drive coil 4, and the objective lens 6 starts moving toward the target track.

By repeatedly executing the above steps S4 to S7, the objective lens 6
If it is detected in step S6 that the time has passed halfway while moving, the drive pulse is set to deceleration (step S6).
8) Repeat the same operation as above. Then, step S5
When it is detected that 3/4 has passed, the process branches to step S9 to output the same signal as in step S7, and whether the interval of the count-up of the track counter while reading the track counter has exceeded a predetermined time (step S1).
1) or waits for one of the conditions of whether the jump of the designated number of tracks has been completed (step S12) (steps S10 to S12), and branches to step S13 when any of the above conditions is satisfied. . In step S13, the switch SW01 is turned on by outputting a control signal, a tracking servo loop is connected, and a normal tracking operation is started. After a certain time t (step S1)
4) The switch SW02 is turned off to stop applying the voltage from the D / A converter 53 (step S15). Thereafter, the objective lens 6 is maintained on the target track by normal tracking servo, and recording or reproduction is performed.

Thus, the signal for driving the drive coil 4 is transmitted to the control unit 52.
The configuration in which the calculation is performed by the calculation in (1) has an effect that the amount of hardware can be saved and an inexpensive device can be provided.

In order to perform the above-described precision access of the track more accurately, it is necessary to consider the frictional force of the spring 4a supporting the objective lens 6. That is, the spring 4a supporting the objective lens 6 is generally supported by a viscous substance in order to improve damping, and a frictional force proportional to the moving speed of the objective lens 6 (so-called F '=- k). For this reason, there is a possibility that the motor may stall even if a constant acceleration voltage is continuously applied. Therefore, a speed control signal e for canceling the frictional force is further added to the drive signal d shown in the embodiment of FIG. The addition is performed so that an apparently constant acceleration can be continuously applied, and stall can be prevented. The circuit configuration in this case is ninth.
FIG. 10 shows the operation waveforms.

In FIG. 9, the difference from the circuit configuration of the embodiment shown in FIG. 1 is that the speed control signal e from the speed detection circuit 48 is different.
This is to be supplied to the D / A converter 45.

That is, as shown in FIG. 10 (d), the speed control signal e generated by the speed detection circuit 48 outputs a voltage that gradually increases during acceleration and a voltage that gradually decreases during deceleration. It is generated in accordance with the pulse interval, that is, the count-up interval of the track count circuit 44.

As shown in FIG. 10, an acceleration / deceleration pulse b generated from an acceleration / deceleration pulse generation circuit 49 and a position control signal c corresponding to the displacement of the objective lens 6 are used as the drive signal d for the objective lens 6.
In addition, except that the speed control signal e is added,
Since the same operation as that of the embodiment shown in FIG. 1 is performed, detailed description of the operation is omitted.

With the above-described configuration, the track access can be performed in consideration of the influence of the frictional force of the spring, so that it is possible to perform the precise track access with the stall prevented.

Note that, in this case as well, the half of the embodiment shown in FIG. 9 is used.
The count detection circuit 46, the full count detection circuit 47, the speed detection circuit 48, and the acceleration / deceleration pulse generation circuit 49
The processing may be performed by the above processing. A block diagram of the circuit configuration in this case is shown in FIG. 7, and a processing flowchart is shown in FIG.

The block diagram of the circuit configuration shown in FIG. 7 is the same as that of the above-described embodiment, and a description thereof will be omitted.

In the processing flowchart shown in FIG. 11, the same parts as those shown in FIG. 8 are denoted by the same reference numerals, and the description thereof will be omitted. That is, if it is determined in step S6 that the movement of the objective lens 6 has not passed a half of the predetermined track,
The speed control signal is calculated from the value of the track counter (step T1), and if it is determined that the value exceeds 1/2, the current value of the track counter is subtracted from the number of tracks to be jumped (predetermined track). A speed control signal is calculated (step T2), and the calculated speed control signal
A value obtained by adding a value obtained by multiplying the value of the track counter by a predetermined coefficient A (same as in the above embodiment) and a driving pulse (acceleration / deceleration pulse) is output to the D / A converter 53 (step T3). The output of the D / A converter 53 is connected to the switch SW02 and the adder 41.
To drive the driving coil 4.

Also, when it is determined in step S4 that 3/4 has passed, the same processing as in steps T2 and T3 (steps T4 and T3) is performed.
5) is performed to generate a drive signal, and the drive coil 4 is driven.

Thus, the signal for driving the drive coil 4 is transmitted to the control unit 52.
The configuration in which the calculation is performed by the calculation in (1) has an effect that the amount of hardware can be saved and an inexpensive device can be provided.

[Effects of the Invention] As described above in detail, according to the present invention, even when a large number of tracks are jumped by the objective lens as the light condensing means, the track jump can be accurately and stably performed. And a recording medium processing apparatus capable of providing the same.

[Brief description of the drawings]

1 to 6 show an embodiment of the present invention. FIG. 1 is a diagram showing a schematic configuration of a tracking control circuit. FIG. 2 is a waveform diagram showing waveforms of respective parts of the tracking control circuit. 3 is a diagram showing the configuration of the disk device, FIG. 4 is a diagram showing the configuration of the optical disk, FIG. 5 is a schematic configuration diagram of the lens actuator, and FIG. 6 is an explanatory diagram showing the relationship between the drive current and the amount of displacement. 7 and 8 show another embodiment of the present invention. FIG. 7 is a diagram showing a schematic configuration of a tracking control circuit, and FIG. 8 is a flowchart for explaining the processing. 9 and 10 show still another embodiment of the present invention. FIG. 9 is a diagram showing a schematic configuration of a tracking control circuit, and FIG. 10 is a waveform diagram showing waveforms of various parts of the tracking control circuit. FIG. 11 shows still another embodiment of the present invention. Example is a flowchart showing a process of. DESCRIPTION OF SYMBOLS 1 ... Optical disk (recording medium), 3 ... Optical head, 4 ... Drive coil (moving means), 4a ... Spring (elastic member), 6 ... Objective lens (condensing means), 8 ... Photodetector, 9 ... Semiconductor laser , OP1… Differential amplifier, 16… Tracking control circuit, 23
... CPU, 42 ... Amplifier, 43 ... Track pulse generator, 44
… Track counting circuit (counting means, counting circuit), 45…
D / A converter (second generation means, conversion circuit), 49 ... acceleration / deceleration pulse generation circuit (first generation means), 50 ... adder, 51,
52: control unit (control means, control circuit), 53: D / A converter, S
W01, SW02… Switch.

Claims (3)

(57) [Claims] 1. A recording medium processing apparatus for recording information on a recording medium having a recording track or reproducing information recorded on the recording medium, comprising: a light beam generating means for generating a light beam; An optical head comprising: a light beam from a light beam generating means; and a detecting means for condensing the light beam on the recording medium by using a condensing means, and outputting a detection signal for the light beam reflected from the recording medium. A first moving means for elastically supporting the light collecting means in the optical head and moving the light collecting means in a direction perpendicular to the direction of the recording track of the recording medium; and supporting the optical head. Moving the optical head in a direction perpendicular to the direction of the recording track of the recording medium;
When the track difference between the recording track of the recording medium irradiated with the light beam by the condensing means of the optical head and the recording track to be accessed is equal to or more than a predetermined number of tracks,
A process of accessing the optical head by moving the optical head by the second moving means, and performing an access by moving the light collecting means by the first moving means when the track difference is equal to or less than a predetermined number of tracks; Means, first generating means for generating an acceleration / deceleration current for moving the light collecting means by the first moving means, and when the light collecting means is moved by the first moving means, Counting means for counting the number of traversing the recording tracks of the recording medium; and a driving current for generating a force balanced with the elastic force of the first moving means caused by the movement of the light condensing means based on the counting result of the counting means. A second generation means for generating the acceleration / deceleration current generated by the first generation means and the second generation means
And the driving current generated by the generating means of
Control means for controlling the movement of the light condensing means by the moving means. 2. A recording medium processing apparatus for recording information on a recording medium having a recording track or reproducing information recorded on the recording medium, comprising: a light beam generating means for generating a light beam; An optical head comprising: a light beam from a light beam generating means; and a detecting means for condensing the light beam on the recording medium by using a condensing means, and outputting a detection signal for the light beam reflected from the recording medium. A first moving means for elastically supporting the light collecting means in the optical head and moving the light collecting means in a direction perpendicular to the direction of the recording track of the recording medium; and supporting the optical head. Moving the optical head in a direction perpendicular to the direction of the recording track of the recording medium;
When the track difference between the recording track of the recording medium irradiated with the light beam by the condensing means of the optical head and the recording track to be accessed is equal to or more than a predetermined number of tracks,
A process of accessing the optical head by moving the optical head by the second moving means, and performing an access by moving the light collecting means by the first moving means when the track difference is equal to or less than a predetermined number of tracks; Means, an acceleration / deceleration pulse generating circuit for generating an acceleration / deceleration pulse for moving the light condensing means by the first moving means, and when the light converging means is moved by the first moving means, A track counting circuit that counts the number of recording tracks traversing a recording track; and generating a force that balances the count value of the track counting circuit with the elastic force of the first moving means generated by the movement of the light condensing means. A conversion circuit for converting into a drive signal, and adding the acceleration / deceleration pulse generated by the acceleration / deceleration pulse generation circuit and the drive circuit converted by the conversion circuit, A control circuit for controlling the movement of the light condensing means by the first moving means. 3. The recording medium processing apparatus according to claim 2, wherein the drive signal from the conversion circuit is cut after a predetermined time after forming a tracking servo loop under the control of the control circuit.