JP2795982B2 - Magneto-optical information recording / reproducing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a magneto-optical information recording / reproducing apparatus capable of recording / erasing information.

[Conventional technology]

As this type of magneto-optical information recording / reproducing apparatus, there is an apparatus which uses a recording medium such as a magneto-optical disc having a magneto-optical effect and records, reproduces or erases information as follows. That is, for example, in the case of using the light modulation method, when recording information, a recording medium is irradiated with a light beam, and an erasing magnetic field having a polarity opposite to a bias magnetic field during recording described later is generated at the irradiated position. In this case, the recording is performed by the recording data after the erasing is performed by the means, and in this case, the recording position is irradiated with a light beam, and a bias magnetic field is applied to the irradiation position by the magnetic field generating means to apply a bias magnetic field. Information is recorded by forming a domain having the same magnetization direction as that of. During playback,
The information thus formed is reproduced based on the reflected light of the light beam irradiated on the recording medium.

Further, for example, in a magnetic field modulation type overwrite device accompanying a request for an increase in writing speed, the magnetic field generating means generates a magnetic field only in a limited range, thereby reducing the size of the field coil, In some cases, the inductance is reduced (that is, the self-inductance is reduced in terms of switching the polarity of the magnetic field at a high speed) to achieve higher-speed magnetic field modulation. That is, the inductance is reduced, and the size of the field coil is reduced. As a result, the magnetic field becomes almost uniform only in a very limited range. Therefore, in this case, regarding the drive system of the optical head and the magnetic field generating means, the optical head for irradiating the light beam is moved in the radial direction of the optical disk as the recording medium, and the magnetic field for generating the magnetic field within a limited range The means is also moved in the same direction, so that the position of the light beam and the position of the magnetic field generating means are substantially matched.

[Problems to be solved by the invention]

However, in magneto-optical recording, it is necessary to form a magnetic field at the irradiation position of the light beam.Therefore, when the magnetic field generating means is moved before or after the movement of the optical head, even when no magnetic field is required, In some cases, heat is generated as the magnetic field generating means moves. Therefore, in the above-described overwrite device, in combination with the above-described purpose of reducing the inductance, the magnetic field coil is reduced in size and weight, and the current to the drive system and the current to the coil are reduced. However, there is a limit to the measures, and only the degree of heat generation is reduced.

On the other hand, in connection with measures against heat generation, a technique for moving the magnetic field generating means and the optical head by separate moving means is disclosed in Japanese Patent Application Laid-Open No. 62-2667.
No. 51 proposes this. However, this document only mentions that only the optical head is moved when the electromagnet (magnetic field generating means) is not required at the time of reproduction, and the stop of the electromagnet is controlled in relation to the medium used. It does not have any functions. From the above, it is inferred that the electromagnet is stopped by the command of regeneration.However, when performing the stop control depending on the command, there is a case where the reliability is lacking in order to prevent heat generation. However, there is room for improvement in terms of further reducing power consumption and heat generation.

The present invention has been made by paying attention to the above points, and when the operation of the magnetic field generating means is unnecessary, the operation can be surely inhibited, and the magnetic field generating means is moved to generate heat. It is an object of the present invention to provide a magneto-optical information recording / reproducing apparatus capable of preventing such a situation and achieving further lower power consumption and lower heat generation.

[Means and actions for solving the problem]

According to the present invention, there is provided a magneto-optical information recording / reproducing apparatus for irradiating a recording medium with a light beam and recording or erasing information by applying a magnetic field to the recording medium. First moving means for moving in the track width direction, magnetic field generating means for generating the magnetic field in a limited range, and moving the magnetic field generating means separately from the first moving means in the track width direction of the medium There is provided a second moving means for performing the operation, and a switch means for inhibiting the operation of the second moving means on the basis of the detection information from the used medium.

As a result, a situation in which the magnetic field generating means is moved to generate heat can be reliably avoided, and power consumption and heat generation can be appropriately and reliably reduced.

〔Example〕

FIG. 1 is a block diagram according to an embodiment of the magneto-optical information recording / reproducing apparatus of the present invention.

In this embodiment, an optical disk is used as a recording medium as described below, and FIG. 1 shows a functional block diagram mainly of a magneto-optical disk drive in that case.

As shown in the figure, the apparatus comprises a control unit 100 and an optical head 1 for irradiating the optical beam to a used optical disk (a magneto-optical disk or a so-called read-only ROM disk described later).
An optical head driving system 120 for driving the magnetic head generating system 130 for generating a magnetic field acting on the magneto-optical disk within a limited range, if applicable;
And a loading unit 150 for inserting and removing a cartridge containing an optical disk, and a driving mechanism (not shown) such as a spindle motor for rotatingly driving the loaded optical disk.
Etc. are provided.

The magnetic field generating means 130 constitutes a magnetic head having a field coil, to which a coil drive current is supplied via a magnetic field control circuit 160 (magnetic head drive circuit) so as to generate a magnetic field required for recording / erasing. . Further, the signal processing circuit 170 of the optical head system controls the power of the semiconductor laser of the optical system,
It consists of a circuit for reading information from the disc during playback.

The optical head drive system 120 is constituted by, for example, a linear motor or the like, and constitutes a moving means (first moving means) for moving the optical disk as a medium in the radial direction (accordingly, in the track width direction). 140 constitutes a moving means (second moving means) for moving the magnetic field generating means 130 in the radial direction separately from the moving means.

The operation of each unit of the apparatus including the above-described drive systems can be controlled by the control unit 100. For example, in the case of a magnetic field modulation type overwrite device, a laser drive circuit in the signal processing circuit 170 constantly irradiates a laser beam of a constant intensity, and the polarity of the magnetic field is converted based on the recording data via the magnetic field control circuit 160. It is controlled so that erasing and recording can be performed once (by modulating the external magnetic field). In addition, in the case of an apparatus of a type in which information is recorded by a laser light modulation method, when erasing, a laser beam is irradiated and information is erased by applying an erasing magnetic field in a certain direction and then erasing. Each of them can be controlled so that recording is performed by applying a magnetic field having a polarity opposite to that of the magnetic field and modulating and irradiating, for example, the intensity of the laser beam according to the recording data. For these types, any of them can be applied.In addition, while irradiating the recording medium with a light beam,
The present invention is applicable as long as information is recorded or erased by applying a magnetic field.

The device further relates to the operation by each drive train 120, 140,
The operation of the magnetic field generating means drive system 140 is prohibited based on information from the medium used to prevent unnecessary heat generation when the magnetic field generating means 130 moves and to achieve low power consumption and low heat generation when unnecessary. Or switch means for permitting. Such a switch means can be configured to include the control unit 100.

Desirably, in this case, a write protection instructing means for instructing the apparatus to prohibit or permit recording or / and erasing on the recording medium is used. In response to this, the apparatus reads the instruction content of the write protection instruction means and reads the instruction content (first detection means).
When the detection result of the detection means indicates that recording or / and erasure is prohibited, the switch means is operated until the medium is replaced, and the magnetic field generating means 1 by the drive system 140 is operated.
The control unit 100 controls so that the movement of 30 is prohibited.

Further, in the case of this control, the write protection means may be located on the surface of a cartridge containing a recording medium (in this embodiment, an optical disk), or in another preferred embodiment, information pre-recorded on the medium, or It may be information additionally recorded on the medium.

In another preferred embodiment, the apparatus comprises a reflectance detecting means (second detecting means) for detecting a reflectance of the recording medium.
When the detection result of the detection means indicates a high reflectance, the switch means described above is operated until the medium is exchanged, so that the movement of the magnetic field generation means 130 by the drive system 140 is prohibited. The control is performed by the unit 100.

When using the instruction content detecting means for detecting the instruction content when the write protection means is on the surface of the cartridge, the means can be provided in the loading section 150 of FIG. 1, and the reflectance detecting means is used. In some cases, the means can be incorporated into the signal processing circuit 170 of FIG.

Hereinafter, each example will be described more specifically with reference to FIGS.

FIG. 2 shows a case where the movement of the magnetic field generating means 130 is prohibited by using a soft switch.
6 is a flowchart illustrating an example of a unit for not activating a magnetic field generation unit driving system 140.

First, the control unit 100 performs detection and determination processing as described below immediately after the cartridge with a built-in disk is inserted. That is, in FIG. 9A, it is determined whether or not the cartridge is inserted by the loading unit 150, and if the cartridge is inserted into the predetermined loading position, in this example of the program, it is determined whether or not there is a write protect instruction on the cartridge. To check.

FIGS. 3 and 4 show write protection instructing means applicable in this example and detecting means for detecting the contents of the instruction (first example).
Are shown in FIG. Figure 3 is IS
O shows the outer shape of the proposed 3.5-inch optical disk cartridge.The cartridge 10 has an opening 10a at one side edge thereof, and a slide member 11 as a write protection instruction means is slidably provided in this opening. Have been. 4 (B) (FIG. 3A-A)
In the state shown in FIG. 4A), the slide member 11 is in the write-protect position (write-protected state). When the slide member 11 is switched to the position shown in FIG. It has become.

On the device side, a micro switch 151 as shown in FIG. 4 is provided as a detecting means facing the cartridge opening at the loading position by the loading section 150, and the state of the write protect instructing means is determined as the detecting means. Is detected. The detection output is taken into the control unit 100 as the instruction content information, and is used for the determination as to whether or not the above-mentioned instruction is present.

In other words, returning to FIG. 2A, if there is a write protect instruction on the cartridge, the control unit 100 defines Command 1 as a seek command, whereas if there is no write protect instruction, Command 2 defines Command 2. Here, command 1
Means that only the seek of the optical head 110 and therefore the movement by the drive system 140 with respect to the magnetic field generating means 130 is prohibited as shown in FIG.
Means that the seek of the magnetic field generating means 130 and the seek of the optical head 110 can be performed as shown in FIG.

After the command is set, in this example of the program, drive initialization is executed, and the control unit 100 waits for the command. Thus, in this case, when a seek command is received in the command waiting state, the control unit 100 controls the corresponding drive system to execute only the command 1, that is, the seek of the optical head 110 (FIG. 2B), or the command 2, that is, the magnetic field. The seek of the generating means 130 and the seek of the optical head (FIG. 10C) are respectively illuminated in accordance with the write protect instruction.

In this manner, the operation of the magnetic field generation unit driving system 140 can be prohibited based on the detection information from the medium used. That it is a write-protected magneto-optical disk,
The user data is detected before recording, reproducing, or erasing the medium, and the movement of the magnetic field generating means 130 can be prohibited until the medium is replaced.

However, according to the above-described method, the determination using the result of the instruction content detection unit is held until the cartridge is replaced, and therefore, it is not necessary to determine each time a command is issued.

In this embodiment, the determination using the result of the above-described detection means is performed before the drive initialization (self-diagnosis, focus search, etc.), but before the command wait, there is no problem even after the drive initialization. In this case, the magnetic field generating means 13
When the movement of 0 is unnecessary, the magnetic field generating means 130 is not moved, and a device with low power consumption and low heat generation can be obtained.

The following is an example of a configuration in which movement of the magnetic field generating means 130 is prohibited using a hardware switch.

As shown in FIG. 5, the magnetic field generating means driving system 140 includes a stepping motor driver 141 to which a driving control signal is input from the control unit 100, and a stepping motor 142 driven by a driving pulse P from the driver 141. And
While the movement of the magnetic field generating means 130 is made by a transmission means 143 such as a wire and a steel belt,
A switch 145 is provided in a power supply path for the driver 141 to control ON / OFF thereof.

The control operation in this case can be performed according to the flowchart shown in FIG. That is, the processing up to the determination of the presence / absence of the write protect instruction may be the same as the case of FIG. 2A, and if there is no write protect instruction,
Control is performed so that the power of the stepping motor driver 141 is turned on, and if there is such an instruction, the power is turned off. In this way, the operation of the drive system 140 is prohibited by not supplying the power of the stepping motor driver 141.

In addition, in the case of such a configuration of the drive system 140, as shown in FIG. 7 and FIG. 8, a configuration in which the above-described prohibition is performed by supplying an inhibit signal to the stepping motor driver 141 can be adopted. That is, if there is no write protection instruction, the driver 141 may be enabled, while if there is an instruction, the driving of the driver 141 may be blocked. Even in this case, if the stepping motor 142 is not driven, the position is maintained. Results in a cartridge
By the above-described processing performed immediately after the insertion, the movement of the magnetic field generating means 130 is surely prohibited until it is replaced, as in the example shown in FIG. Heat generation can be avoided.

When a configuration is required in which the field coil of the magnetic field generating means must be retracted when the cartridge 10 is inserted or ejected, control may be performed so as to permit movement only during the retraction. However, if the evacuation is guaranteed for any reason, it is only necessary to maintain that position.

FIG. 9 shows an example in which the reflectance detecting means (second detecting means) is used, and FIG. 9 (A) shows an example of the configuration of a pickup capable of recording, reproducing and erasing a magneto-optical disk. I have.

The pickup, in the illustrated example, after converting the light beam from the semiconductor laser 181 into parallel light with the collimator lens 182,
A recording medium such as a magneto-optical disk 1 is formed by an objective lens 185 via a beam shaping prism 183 and a polarizing beam splitter 184.
Focus on 2.

The reflected light from the magneto-optical disk 12 is
After passing through 5, the light is separated from the incident optical path by the polarization beam splitter 184, and guided to the polarization beam splitter 186, where it is separated into a reproduction signal detection system and a servo signal detection system. That is,
In the former system, the light is incident on a λ / 2 wavelength plate 187, thereby rotating the polarization plane by 45 °, and then converging with a condenser lens 188, leading to a polarization beam splitter 189, and
Thus, the light is separated into a P-polarized light component and an S-polarized light component, and received by the photodetectors 190 and 191, respectively, and a reproduced signal is obtained based on the outputs of the photodetectors 190 and 191.

On the other hand, in the latter servo signal detection system, the condenser lens 192
To the half prism 193, and one of the separated lights is received by the tracking servo photodetector 194, and the other is received by the focusing servo photodetector 196 through the knife edge 195.

At the time of recording / erasing, as shown in FIG.
Field coil 131 is located on the opposite side of the magneto-optical disk 12.

Here, focusing on the reflectivities of a rewritable magneto-optical disk and a read-only ROM disk, the reflectivity of the former is around 20%, whereas that of the latter is 60% to 90%. Too much and very expensive. Therefore, this embodiment utilizes this. That is, when the ROM disk is irradiated with a laser power suitable for reproducing a general magneto-optical disk, the amount of light returning to the photodetectors 190, 191 and 194 is 3 to 5 times the returning light amount in the case of a magneto-optical disk. Therefore, as shown in FIG. 9 (B), such information on the amount of return light is used as one input of the comparator 171 and is compared with a predetermined reference value of the other input.
It is possible to obtain a determination output for determining whether the used recording medium is a ROM disk or a magneto-optical disk.

In this embodiment, the reflectivity of the medium is detected as described above, and the control unit 100 captures the information, and as a result of the detection, if the reflectivity is high, that is, in the case of a ROM disk, as described above, The movement of the magnetic field generating means 130 by the magnetic field generating means driving system 140 is inhibited by operating a soft switch or a hardware switch until the medium is replaced.

Thus, even if it is not write protected,
Detects that the medium is non-recordable or erasable before recording, reproducing or erasing user data on the medium, and prohibits movement of the magnetic field generating means 130 until the medium is replaced. can do.

FIG. 10 shows an example of recording or / and recording based on information previously recorded on a medium or additionally recorded information.
10 is a flowchart illustrating an example of a control operation in a case where movement of the magnetic field generation unit 130 is prohibited by operating a soft switch, a hardware switch, and the like until a medium is exchanged when erasing is prohibited.

The 3.5-inch optical disc proposed by the ISO mentioned above has an inner manufacture zone, an inner control track zone, and an outer control track zone in a predetermined format. ,
Various areas including an outer manufacturer (Outer Manufacturer) zone are set. In the control track zone, the same contents of all sectors on both the inner circumference and the outer circumference are recorded as various kinds of information by a concavo-convex signal or the like at the time of disc manufacture. The seventh byte of this information contains the medium. Information about the type of is recorded. That is, if the seventh byte is hexadecimal and OOH (H indicates hexadecimal), it is read-only (ROM) and it is 2OH
Then, it is a rewritable MO (magneto-optical) disk.

Here, at the time of loading the disk, if the initialization of the drive is completed, at least the seek and read are possible on the device side. Therefore, by reading the seventh byte as described above, the disk becomes a read-only ROM disk. If the disk is inserted, it will not be written or erased, so there is no need to energize the field coil to generate a magnetic field. No need to seek 130.

Therefore, in this embodiment, the control unit 100 executes the following processing when the cartridge is inserted as shown in FIG. That is, as in the case of FIG. 2A, first, cartridge insertion is confirmed, drive initialization is performed after insertion confirmation, then information on the inner or outer control track is read, and based on that, it is checked whether the medium is ROM. I do.

Therefore, the control after the ROM determination processing is performed in the second mode.
The case may be the same as in the cases of FIGS. (A) to (C). In the case of a ROM, the above-described command 1 is defined. In the case of a ROM, the above-described command 2 is defined.

Thus, also in this embodiment, when the result of the above determination is that the disk is a ROM disk, that is, when the recording / erasing is unnecessary, the magnetic field generating means drive system 140 is surely replaced until the medium is replaced. As described above, the prohibition of the operation can be ensured, and it is not necessary to determine each command.

Even though the ROM disk is inserted, even if the user performs an operation for recording / erasing by mistake or the like, the situation in which the magnetic field generating means 130 is moved to generate heat without fail is reliably prevented. It shows high correspondence. The command of reproduction does not depend on the stop of the magnetic field generating means.

In the method shown in FIG. 10, it can be easily understood that the processing after the routine for determining whether or not the ROM is the same as the configuration and control described in FIGS. 5 to 8 can be applied. Therefore, the present invention may be implemented with such modification, and the same operation and effect can be obtained.

In the above description, the information recorded in advance is used. However, the present invention is not limited to this, and the movement of the magnetic field generating means 130 is performed by using the MO disk as if it were a ROM disk as follows. Similarly, it can be appropriately prohibited.

As described above, the 3.5-inch optical disc has a manufacturing zone and a user zone as setting areas, and a part of the zone is used as a control track,
Alternatively, by using a part of the user track as a control track, the MO disk can be used as if it were a ROM disk. That is, depending on the data to be recorded, there is a case where after the desired data is recorded on the MO disk, it is desired to prohibit the data from being erased or rewritten. Therefore, when it is necessary to prevent such erasing and rewriting, information indicating that “it should be treated as ROM” should be added to the track regarded as the control track after recording the desired data. .

When using the MO disk having the additional recording as described above, the apparatus can appropriately prohibit the movement of the magnetic field generating means 130 by an operation according to the processing shown in FIG. 10, for example. That is, the procedure is basically the same as the case where the RMO is recorded on the regular control track as described above, and it is determined whether or not additional recording is performed, and if applicable, the command 1 is defined. I just need.

In each of the above examples, an optical disk is described as an example of a medium, but the present invention is also applicable to a medium using a magneto-optical card as a similar medium.

〔The invention's effect〕

According to the present invention, when the movement of the magnetic field generating means is unnecessary, the movement can be surely prohibited, so that it is possible to prevent the magnetic field generating means from being moved and heated.
In addition, since it is not necessary to determine each time a command is issued and the magnetic field generating means is not stopped by a command of reproduction, the above prevention function can be made higher and a device with low power consumption and low heat generation can be configured. .

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a functional block diagram mainly showing a configuration of a magneto-optical disk drive, FIG. 2 is a flowchart for explaining an example of the operation, FIG. FIG. 4 is a perspective view of an optical disk cartridge showing an example of a write protection instructing means. FIG. 4 is a diagram for explaining an example of the instruction content detecting means and a detection mode thereof. FIG. FIG. 6 is a block diagram of an example of a magnetic field generating means driving system including FIG. 6, FIG. 6 is a flowchart for explaining the operation in the case of the configuration of FIG. 5, and FIG. 7 is the same block as FIG. FIG. 8, FIG. 8 is a flowchart for explaining the operation, FIG. 9 is a diagram showing an example of the reflectance detecting means, and FIG. 10 is a diagram showing one example of the control operation when using information recorded on the medium to be used. Is a flow chart for explaining a. 10: cartridge, 11: slide member 12: magneto-optical disk, 100: control unit 110: optical head, 120: optical head drive system 130: magnetic field generating means, 131: field coil 140 ... magnetic field generating means drive system 141 ... stepping motor driver 142 ... stepping motor 143 ... transmission means, 145 ... switch 150 ... loading section, 151 ... micro switch 160 ... magnetic field control circuit, 170 ... signal processing Circuit 171… Comparator, 181… Semiconductor laser 185 …… Objective lens 190,191,194,196 …… Photodetector

Claims (1)

(57) [Claims] 1. A magneto-optical information recording / reproducing apparatus for recording or erasing information by irradiating a recording medium with a light beam and applying a magnetic field to the recording medium, comprising: First to move in the direction
Moving means, a magnetic field generating means for generating the magnetic field in a limited range, a second moving means for moving the magnetic field generating means separately from the first moving means in the track width direction of the medium, Switch means for prohibiting the operation of the second moving means based on the detection information from the used medium side.