JPH05242557A - Optical disk device - Google Patents

Abstract

PURPOSE:To condense the constitution of an optimization control and to reduce a device cost only by setting a previously stored constant number on a control system controlling each number of the control system in accordance with the maker of an attached optical recording medium. CONSTITUTION:When the kind of a magneto-optical disk 4 is different, depending on the kinds of the material of a used substrate and a magneto- optical recording material, for each magneto-optical disk 4, the gain of the focusing control of the control system of an optical pick-up device 5, the gain of a tracking control and a value for identifying a focus pulling-in are respectively decided. Thus, by storing them, for each magneto-optical disk 4, the operation of the optical pick-up device is optimized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk device using an optical recording medium on which control information of a predetermined information format is recorded as a recording medium.

[0002]

2. Description of the Related Art In recent years, ISO (International Organization for Standardization) is creating a standard for defining the shape, physical characteristics, physical format of a magneto-optical disk used as an optical recording medium, and the shape of a disk cartridge.

As described above, when the ISO standard is created, magneto-optical disk cartridges are supplied from a plurality of manufacturers, so that the cost of the magneto-optical disk cartridge is reduced. At the same time, it is expected that magneto-optical disk devices will be supplied from a plurality of manufacturers, the cost of the magneto-optical disk devices will be reduced, and the spread of the magneto-optical disk devices will be promoted.

[0004]

However, since the above-mentioned ISO standard does not specify the material of the magneto-optical disk, it is considered that magneto-optical disk cartridges using various materials are supplied.

For example, the substrate of the magneto-optical disk is polycarbonate (PC), polymethylmethacrylate (P).
MMA), amorphous polyolefin (APO), glass plate, etc. are used. Similarly, various magneto-optical materials are used.

In this way, when the material of the substrate is different,
There are good and bad mechanical properties of magneto-optical disks such as eccentricity, surface deviation, and inclination of recording surface.
In addition, different magneto-optical materials have different recording sensitivities, and therefore different laser beam intensities required for data recording.

Therefore, in the magneto-optical disk cartridges supplied from a plurality of manufacturers, the mechanical characteristics of the magneto-optical disk and the recording sensitivity characteristics of the recording film (magneto-optical material) are different, and therefore, the magneto-optical disk device. Then, it is necessary to perform optimum control according to the characteristics of the mounted magneto-optical disc cartridge, which causes a disadvantage that the device configuration becomes complicated.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an inexpensive optical disk device which can use optical recording media supplied from a plurality of manufacturers.

[0009]

According to the present invention, in an optical disc device using an optical recording medium on which control information of a predetermined information format is recorded as a recording medium, a focus gain corresponding to vendor mark information included in the control information is set. The control information is read from the stored storage means and the mounted optical recording medium, the focus gain corresponding to the vendor mark information included in the control information is read from the storage means, and data is recorded / reproduced on the optical recording medium. The focus control means of the optical pickup device is provided with a control means for setting the read focus gain.

Further, in an optical disc device using an optical recording medium in which control information of a predetermined information format is recorded as a recording medium, a storage means for storing a tracking gain corresponding to vendor mark information included in the control information is mounted. The tracking control means of the optical pickup device that reads the control information from the optical recording medium, reads the tracking gain corresponding to the vendor mark information included in the control information from the storage means, and records / reproduces data on / from the optical recording medium. The control means is provided for setting the read tracking gain.

Further, in an optical disc device using an optical recording medium in which control information of a predetermined information format is recorded as a recording medium, a storage means for storing a focus pull-in determination threshold value corresponding to vendor mark information included in the control information. An optical pickup that reads the control information from the mounted optical recording medium, reads a focus pull-in determination threshold value corresponding to vendor mark information included in the control information from the storage unit, and records / reproduces data on / from the optical recording medium. The focus control means of the apparatus is provided with control means for setting the read focus pull-in determination threshold value.

[0012]

Therefore, since each constant of the control system is controlled according to the manufacturer of the optical recording medium mounted, the optical recording medium can be optimally controlled. Further, since it is only necessary to set the constants stored in advance in the control system, the configuration of the optimization control can be reduced, and the device cost can be reduced.

[0013]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows the configuration of a magneto-optical disk device according to an embodiment of the present invention. In the figure, elements that generate an auxiliary magnetic field necessary for data recording / erasing are omitted.

In FIG. 1, a magneto-optical disk 4 is removably attached to a turntable 3 fixed to a rotary shaft 2 of a spindle motor 1, and a recording surface of the magneto-optical disk 4 has an optical disk. Data is recorded / reproduced / erased by the pickup device 5. Further, the optical pickup device 5 is additionally provided with a seek mechanism 6 for moving the magneto-optical disk 4 in the radial direction.

Further, this magneto-optical disk device is provided with an eject mechanism (not shown) for ejecting the mounted magneto-optical disk 4.

2A and 2B illustrate an optical system of the optical pickup device 5. In addition, in this optical system,
Detect the focus error signal using the knife edge method,
The tracking error is detected by the push-pull method.

In the figure, the laser light output from the semiconductor laser device 10 is converted into parallel light by the coupling lens 11, passes through the beam splitter 12, enters the objective lens 13, and is focused by the objective lens 13. Then, an image is formed on the recording surface of the magneto-optical disk 4.

The reflected light from the magneto-optical disk 4 is converted into substantially parallel light by the objective lens 13, reflected by the beam splitter 12, guided to the objective lens 14, and focused by the objective lens 14. Passes through the half-wave plate 15 and its plane of polarization is rotated by 45 degrees.

The S-polarized component and the P-polarized component of the reflected light that has passed through the half-wave plate 15 are reflected by the polarization beam splitter 16. The light of the S-polarized component reflected by the polarization beam splitter 16 is incident on the light receiving element 17 for track error detection (see FIG. 4B) whose light receiving surface is divided into two in the tracking direction.

Further, 60 to 90% of the light flux of the P-polarized component transmitted through the polarization beam splitter 16 is reflected by the splitting mirror 18 constituting the knife edge and is incident on the light receiving element 19, and its The remaining portion of the P-polarized component light is incident on the light receiving element 20 for focus error detection, whose light receiving surface is divided into two by a dividing line parallel to the ridgeline 18a of the dividing mirror 18.

According to the ISO standard, a control track having control information recorded therein is provided at a predetermined radial position on the magneto-optical disk 4. An example of the control information is shown in FIG.

In this control information, the 0th to 13th
The byte has the format format of the recording medium, rotation format,
The medium characteristic information A indicating the modulation format, the error correction code generation rule, the number of bytes of user data per sector, the number of sectors per track, and the like is arranged, and the 14th to 17th bytes include the magneto-optical disk 4. Mark information (vendor unique information) that represents the manufacturer that manufactured the product
The medium characteristic information B indicating the reference wavelength, the number of revolutions, the intensity of the laser beam at each radial position, etc.
Are arranged.

Also, the recording information of the control track,
Also, the data of the header information part which is recorded in advance in the user data area is recorded by forming pits (small holes). Therefore, the reproducing method for reproducing these information is as follows. This is different from the reproducing method used when reproducing user data (described later).

By the way, the recording characteristics of the magneto-optical disk 4 depend on the linear velocity of the magneto-optical disk 4, and when the rotating speed of the magneto-optical disk 4 increases, the power of the laser beam required for data recording also increases.

That is, for example, as shown in FIG. 4, the power Pth of the laser beam required for recording data on the magneto-optical disk 4 changes as the rotation speed of the magneto-optical disk 4 changes. It changes linearly.
Further, when the manufacturers are different and the types of the magneto-optical disk 4 are different, the graphs showing the relationship between the rotation speed and the power Pth are also different.

The upper limit of the power of the laser beam of the optical pickup device 5 is limited by the performance of the semiconductor laser device 10 used. Therefore, in the same magneto-optical disk device, the upper limit of the rotation speed is limited for each magneto-optical disk 4.

At the same time, when the type of the magneto-optical disk 4 is different, the mechanical characteristics of the magneto-optical disk 4 are different depending on the material of the substrate and the type of the magneto-optical recording material used. Optimal values of the focusing control gain, the tracking control gain, and the threshold value for determining the focus pull-in of the control system (described later) of the optical pickup device 5 are determined.

Therefore, in this embodiment, the magneto-optical disk 4 is used.
The optimum values of the rotation speed, the focusing gain, the tracking gain, and the focus pull-in threshold value are set in advance for each type, and stored in advance, so that the control system of the optical pickup device 5 for each magneto-optical disk 4 is stored. The behavior of can be optimized.

FIG. 5 shows a control system of a magneto-optical disk device according to an embodiment of the present invention. In the figure, description of parts that are not directly related to the present invention is omitted.

In the figure, the light receiving surface 18 of the light receiving element 18 is shown.
The received light signal Pa output from a is added to the plus side input end of the subtractor 21 and one input end of the adder 22, and the received light signal Pb output from the light receiving surface 18b is the minus side of the subtractor 21. It is added to the side input end and the other input end of the adder 22.

The light receiving signal Pc of the light receiving element 20 is supplied to the adder 2
3 and one plus side input end of the adder / subtractor 24. Light receiving surface 2 of light receiving element 21
The light reception signal Pd output from 1a is added to one input end of the adder 25 and the plus side input end of the subtractor 26, and the light reception signal Pe output from the light receiving surface 21b.
Is added to the other input end of the adder 25 and the minus side input end of the subtractor 26.

The output signal of the subtracter 21 is added to the tracking servo control unit 28 via the variable gain amplifier 27 as the tracking error signal ET, and the adder 22 is added.
The output signal of is added to the input end of the adder 23 and the minus side input end of the adder / subtractor 24.

The output signal of the subtractor 26 is applied as a focusing error signal EF to the focusing servo control section 30 via the variable gain amplifier 29. The output signal of the adder 25 is the input terminal of the adder 23. Adder / subtractor 24
Positive-side input end of the
Focusing servo control unit 30 as sum signal SS of F
Has been added to.

The tracking servo control section 28 forms a tracking control signal ST for changing the tracking error to 0 based on the input tracking error signal ET. The tracking control signal ST is the tracking actuator drive section 31. Has been added to.

Tracking actuator drive unit 31
On the basis of the input tracking control signal ST, supplies a drive current to a tracking actuator for moving the objective lens 13 in the tracking direction in the objective lens moving mechanism attached to the objective lens 13.

The focusing servo control section 30 determines whether or not the amount of the focus error of the objective lens 13 is in the focusing controllable area based on the input sum signal SS. Based on the focusing error signal ET, a focusing control signal SF for changing the focusing error to 0 is formed, and the focusing control signal SF is applied to the focusing actuator driving section 32.

Focusing actuator driver 32
In the objective lens moving mechanism, a drive current is supplied to a focusing actuator that moves the objective lens 13 in the front-back direction of the optical axis based on the input focusing control signal SF.

The adder 23 includes the light receiving elements 18, 20, 21.
Which forms the sum total of all the received light signals, and its output signal is added to the pre-format identification unit 33 as the pre-format signal RF.

The pre-format identification section 33 reproduces pre-format information such as control track recording information and user data area header information based on the input pre-format signal RF, and its output signal is , Preformat data PFD is added to the control unit 34.

The adder / subtractor 24 includes the light receiving elements 18, 20, 2
The difference between the S-polarized component and the P-polarized component in all one received light signal is calculated as a magneto-optical signal MO, and the magneto-optical signal MO is added to the signal reproducing unit 36.

The signal reproducing section 36 receives the input magneto-optical signal M.
The reproduction data RD recorded on the magneto-optical disk 4 is formed based on O, and the reproduction data RD is formed.
Have been added to the decoder 36.

The decoder 36 uses the error correction code added to the input reproduction data RD to reproduce the reproduction data RD.
Is detected and corrected, and its output data is added to the control unit 34 as reproduction data RDa.

The encoder 37 adds a predetermined error correction code to the recording data WD output from the controller 34, and the output data is added to the semiconductor laser drive controller 38 as a recording signal WDa. ing.

The semiconductor laser drive control unit 38 includes the control unit 3
When the reproduction mode is set from No. 4, the semiconductor laser device 10 is driven to light at a predetermined reproduction level. When the recording mode is set by the controller 34, the semiconductor laser device 10 is driven to be lit in the recording mode based on the recording signal WDa supplied from the encoder 37.

The position detector 39 detects the position of the optical pickup device 5 moved by the seek mechanism 6, and its detection signal is applied to the seek motor controller 40 as a position detection signal SP.

The seek motor control section 40 drives the seek motor 41, which is the drive source of the seek mechanism 6, so that the value of the position detection signal SP becomes a value corresponding to the target position instructed by the control section 34. It is a thing.

The speed detector 42 detects the rotation speed of the spindle motor 1, and its detection signal is applied to the spindle motor control section 43 as a speed detection signal SV.

The spindle motor control section 43 drives the spindle motor 1 so that the value of the speed detection signal SV becomes a value corresponding to the target speed instructed by the control section 34.

The eject motor 44 is for driving an eject mechanism for ejecting the mounted magneto-optical disk 4, and the eject motor 44
Are driven by a motor drive unit 45 controlled by the control unit 34. The sensor group 46 includes a media-in sensor that detects that the magneto-optical disk 4 is mounted, a sensor that detects that the mounted magneto-optical disk 4 is in a write-protected state, and the like. The signal is applied to the control unit 34.

The host interface circuit 47 is for exchanging various data with a host device which uses this optical disk drive device as an external storage device.

The control section 34 controls the operation of the magneto-optical disk device, and includes variable gain amplifiers 27 and 29.
The gain is set to and the operation of other parts is controlled, and various data is exchanged with the host device via the host interface circuit 47.

As described above, depending on the type of the magneto-optical disk 4 mounted in the magneto-optical disk device, the rotation speed of the magneto-optical disk 4, the focusing gain, the threshold for determining the focus pull-in, and the tracking gain are set. The optimum value is different. Therefore, in this embodiment, setting information as shown in FIG. 6 is formed for each magneto-optical disk 4 and stored in the control unit 34.

This setting information is vendor mark information indicating a vendor mark recorded on the control track by the manufacturer of the magneto-optical disk 4, rotational speed information indicating the optimum value of the rotational speed of the magneto-optical disk 4, Focusing gain information indicating the optimum value of the focusing gain of the magneto-optical disk 4, focus pull-in threshold information indicating the optimum value of the threshold for focus pull-in determination of the magneto-optical disk 4, and tracking gain of the magneto-optical disk 4. It consists of tracking gain information that represents the optimum value.

Here, the threshold for the focus pull-in determination will be described.

When the focusing error is detected by the knife edge method, the focusing error signal EF obtained corresponding to the focus shift amount draws a so-called S-shaped curve as shown in FIG. 7B.

On the other hand, the sum signal SS described above is the same as shown in FIG.
As shown in, a convex curve is drawn upward with the position where the focus shift amount is 0 as the apex. Therefore, the range of the focus deviation amount obtained by level-determining the sum signal SS with an appropriate threshold value THf is defined as the effective range of the focusing error signal EF, and when the value of the focus deviation amount is within this range. Further, by performing the focusing servo control, the focusing servo control can be performed efficiently and stably.

With the above construction, when the magneto-optical disk 4 is inserted into the magneto-optical disk device and positioned at a predetermined position, the media-in sensor of the sensor group 46 performs the detection operation,
As a result, the control unit 34 operates as shown in FIG.

That is, first, the spindle motor control unit 43 is set to a standard value of the number of revolutions of the spindle motor 1 (for example, 1800 (rpm)), and the rotation of the spindle motor 1 is started (process 101).

As a result, when the rotation speed of the spindle motor 1 reaches a predetermined value, a predetermined initial value of the focusing gain is set in the variable gain amplifier 29, and a predetermined initial value of the focus pull-in threshold is set. The operation of the focusing servo control unit 30 is started with the focusing servo control unit 30 set (process 102).

Then, the focusing servo control section 30
Waits until the control lock state is reached (step 103). When the focusing servo control unit 30 is locked, the seek motor control unit 40 is instructed to move to the target position while designating the target position corresponding to the position of the control track, and the control track can be accessed. State (Process 10)
4).

Next, the operation of the tracking servo control unit 28 is started with the predetermined initial value of the tracking gain set in the variable gain amplifier 27 (process 105). When the tracking servo control is locked, the preformat identification unit 33
The contents of the control track are read based on the pre-format data PFD output from
6) It is checked whether or not the vendor mark of the management information is registered in any of the vendor mark information of the stored setting information (process 107).

As a result, when the read vendor mark is registered (the result of judgment 108 is YE
S), and reads the rotation speed information, the focusing gain information, the focus pull-in threshold information, and the tracking gain information of the setting information in which the vendor mark is set in the vendor mark information (Process 10).
9), the rotation speed information is set in the spindle motor control unit 43, and the focusing gain information is set in the variable gain amplifier 29.
, The focus pull-in threshold information is set in the forcings servo control unit 30, the tracking gain information is set in the tracking servo control unit 28, and those values are set to the optimum values corresponding to the mounted magneto-optical disk 4. Is reset (step 110), and a normal standby state is entered.

On the other hand, when the read vendor mark is not registered in any of the setting information and the result of determination 108 is NO, the seek motor control unit 40 moves the optical pickup device 5 to the home position ( (Process 111), the spindle motor control unit 43 stops the spindle motor 1 (Process 112), outputs a control signal to the motor drive unit 45, and outputs the eject motor 44.
Is operated to eject the magneto-optical disk 4 (Processing 11
3) An error message indicating that the installed magneto-optical disk 4 is not a specified one is notified to the host device via the host interface circuit 47 (Processing 11
4) Move to the error end state.

As described above, in this embodiment, when the magneto-optical disk 4 is mounted, first, the control information recorded on the control track is read with each element of the control system being initialized, and the vendor mark is read. Check whether is registered. When the vendor mark is registered, each element of the control system is reset to the state corresponding to the registered value, and the subsequent data access operation is performed.

If the read vendor mark is not registered, the magneto-optical disk 4 is ejected and an error is notified that the mounted magneto-optical disk 4 is not appropriate. ..

Therefore, each state of the control system is set to the optimum state for accessing the mounted magneto-optical disk 4, so that the data recording / reproducing / erasing operation for the magneto-optical disk 4 can be performed efficiently. Well done,
The data access speed can be greatly improved.

By the way, in the above embodiment, the focusing error is detected by the knife edge method, and
The tracking error is detected by the push-pull method, but if any other detection method is used,
The present invention can be similarly applied.

[0069]

As described above, according to the present invention,
Since each constant of the control system is controlled according to the manufacturer of the mounted optical recording medium, the optical recording medium can be optimally controlled. Further, since it is only necessary to set the constants stored in advance in the control system, it is possible to reduce the configuration of the optimization control and reduce the device cost.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a magneto-optical disk device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing an example of an optical system of an optical pickup device.

FIG. 3 is a schematic diagram showing an example of control information recorded on a control track.

FIG. 4 is a graph showing the relationship between rotation speed and required power.

5 is a block diagram illustrating a control system of the apparatus shown in FIG.

FIG. 6 is a schematic diagram showing an example of setting information.

FIG. 7 is a graph chart for explaining a relationship between a focusing error, a sum signal, and a focus pull-in threshold.

FIG. 8 is a flowchart showing an example of processing performed immediately after the magneto-optical disk is mounted.

[Explanation of symbols]

 1 Spindle Motor 4 Magneto Optical Disk 27, 29 Variable Gain Amplifier 28 Tracking Servo Control Section 30 Focusing Servo Control Section 34 Control Section 43 Spindle Motor Control Section

Claims (3)

[Claims] 1. An optical disk device using an optical recording medium having control information recorded in a predetermined information format as a recording medium, wherein a storage unit storing focus gain corresponding to vendor mark information included in the control information is mounted. The control information of the optical pickup device is read from the optical recording medium, the focus gain corresponding to the vendor mark information included in the control information is read from the storage device, and the focus control device of the optical pickup device records / reproduces data on / from the optical recording medium. An optical disk device comprising a control means for setting the read focus gain. 2. An optical disk device using an optical recording medium having control information recorded in a predetermined information format as a recording medium, wherein a storage unit storing a tracking gain corresponding to vendor mark information included in the control information is mounted. The tracking control means of the optical pickup device that reads the control information from the optical recording medium, reads the tracking gain corresponding to the vendor mark information included in the control information from the storage means, and records / reproduces data on / from the optical recording medium. An optical disk device comprising a control means for setting the read tracking gain. 3. An optical disc device using an optical recording medium on which control information of a predetermined information format is recorded as a recording medium, and storage means for storing a focus pull-in determination threshold value corresponding to vendor mark information included in the control information. An optical pickup that reads the control information from the mounted optical recording medium, reads a focus pull-in determination threshold value corresponding to the vendor mark information included in the control information from the storage unit, and records / reproduces data on / from the optical recording medium. An optical disk device, wherein the focus control means of the apparatus is provided with control means for setting the read threshold for focus pull-in determination.