JP3363172B2 - Magnetic recording / reproducing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of recording / reproducing information using a magnetic disk as an information recording medium.

[0002]

2. Description of the Related Art As is well known, a recording / reproducing method using a disk having a magnetic layer as an information recording medium is a magnetic method using a magnetic disk such as a flexible magnetic disk (floppy disk) or a hard disk. ,
There is a magneto-optical method using a magneto-optical disk or the like.

The magnetic method is carried out by using a magnetic recording / reproducing apparatus including a magnetic recording medium and a magnetic head, and the magnetic recording medium is contacted or not contacted with the magnetic head. The magnetic signal output from the magnetic head is recorded on the magnetic layer at room temperature, and the magnetic signal recorded on the magnetic recording medium is picked up by the magnetic head at room temperature to reproduce the signal. The signal is erased by applying a magnetic field in the erasing direction from the magnetic head to the magnetic layer. On the other hand, the magneto-optical method is performed by using a magneto-optical recording / reproducing device including a magneto-optical recording medium, an optical head, and a magnetic head or a magnet, and the magneto-optical recording and reproducing apparatus are arranged to face each other. While moving the magneto-optical recording medium between the optical head and the magnetic head or magnet, the laser beam is irradiated from the optical head to the magneto-optical recording medium to raise the temperature of the magnetic layer to near the Curie temperature or the compensation temperature. , A magnetic signal is applied from the magnetic head or magnet to the heated portion to record information, and low-level linearly polarized light is irradiated along the recording track to correspond to the arrangement of the inverted magnetic domains formed in the magnetic layer. The signal is reproduced by detecting the change in the Kerr rotation angle of the reflected light. The signal is erased by irradiating the magneto-optical recording medium with a laser beam from the optical head to raise the temperature of the magnetic layer to near the Curie temperature or the compensation temperature, while applying a magnetic field in the erasing direction to the elevated temperature portion from the magnetic head or the magnet. It is performed by applying.

The magnetic layer of flexible magnetic disks (floppy disks) and hard disks is composed of γ-Fe ₂ O ₃
Powder, Co-containing Fe ₂ O ₃ powder, Fe ₃ O ₄ powder, Co
Containing Fe ₃ O ₄ powder, Fe powder, Co powder, Fe-Ni
Magnetic powder such as alloy powder coated with binder and organic solvent and dried, or Co, Fe, Ni, C
o-Ni alloy, Co-Cr alloy, Co-P alloy, Co-
It is formed by vacuum-depositing a ferromagnetic material such as Ni-P alloy, Al-Co alloy, and Al-Ni-Co alloy, and has high chemical stability, excellent corrosion resistance, and can be manufactured at low cost. There is an advantage. In addition, the magnetic recording medium has a function of rewriting a previously recorded signal to a new signal by writing a new signal in an area where the signal is recorded, that is, an overwrite function, and an effective transfer rate of the signal. Has the advantage of being fast. On the other hand,
Since the recording density of the magnetic recording medium is limited by the gap width of the magnetic head, there is a drawback that the recording density cannot be increased.

On the other hand, the advantages and disadvantages of the magneto-optical recording medium are opposite to those of the magnetic recording medium. Since a perpendicularly magnetized film is used as a magnetic layer and a fine inverted magnetic domain is formed to record a signal, high recording is achieved. Although the density can be obtained, the signal cannot be overwritten unless the film structure of the medium and the drive device are specially devised, and the effective transfer rate of the signal as in the magnetic recording / reproducing system cannot be obtained. As a magnetic layer of a magneto-optical recording medium, a rare earth-transition metal-based perpendicular magnetization film is currently most suitable, but this kind of perpendicular magnetization film has low chemical stability and poor corrosion resistance. In addition, there is a drawback that the long-term storage property of the signal is poor. When the magneto-optical recording / reproducing system is configured to be overwritable, the film structure of the medium and the drive device are complicated and the system becomes expensive.
Further, in order to improve the corrosion resistance of the magneto-optical recording medium, many protective layers must be laminated, which also increases the cost.

[0006]

In the technical field of information recording, it is particularly required that the recording capacity be high, the long-term storage property be excellent, the signal transfer rate be fast, and the cost be low.

The present invention has been made to solve the above technical problems, and the problem is that it is a completely new combination of the advantages of the magnetic recording / reproducing method and the magneto-optical recording / reproducing method. It is to provide a method of recording and reproducing information.

[0008]

In order to achieve the above object, the present invention provides a magnetic recording comprising a magnetic disk having a tracking guide groove and a magnetic layer as an information recording layer, an optical head and a magnetic head. In a magnetic recording / reproducing method of recording and reproducing information by using a reproducing device, at the time of recording information, a pre- recorded magnetically written on the magnetic disk is used.
The format signal is detected to detect the optical head and magnetic field.
The magnetic layer is positioned at a desired area, the laser beam is irradiated from the optical head to a desired information recording area on the magnetic disk to raise the temperature of the magnetic layer, and the magnetic layer is heated from the magnetic head. A pulsed magnetic signal larger than the coercive force of the magnetic field is applied to the magnetic layer, and at the time of reproducing information, the pre- recorded magnetically written on the magnetic disk.
The optical head and magnetic head are detected by detecting the format signal.
The signal is positioned in a desired area and signals from the area are magnetically read.

Tracking control of the optical head and the magnetic head during recording and reproduction of information can be performed by irradiating the guide groove with a laser beam from the optical head and obtaining a tracking error signal from the reflected light. . In addition, optics for recording and reproducing information
Positioning the head and magnetic head in the desired area is
Pre-format magnetically written on a magnetic disk
This can be done by detecting the signal with a magnetic head.
Wear.

The arrangement of the optical head and the magnetic head with respect to the magnetic disk is not limited at all, and the optical head and the magnetic head can be arranged on both sides of the magnetic disk so as to face each other. The optical head and the magnetic head can be arranged adjacent to each other on one side of the disk. Further, the magnetic disk can be handled alone or in a state of being rotatably housed in a disk cartridge. The structure of the disk cartridge is not particularly limited, but it is particularly preferable to use a disk cartridge having a disk retainer that rotates together with the magnetic disk therein in order to easily apply a magnetic field to the magnetic layer.

As the magnetic disk, (1)
An in-plane magnetized film or perpendicular magnetization whose Curie temperature or compensation temperature is in the range of 50 ° C. to 400 ° C. and whose coercive force at room temperature is significantly larger than the magnetic signal strength acting on the magnetic layer from the magnetic head or magnet. (2) A transparent substrate having a guide groove formed on one side, a photothermal conversion layer provided on the guide groove forming surface of the transparent substrate, and a photothermal conversion layer provided on the photothermal conversion layer. A laminated magnetic layer, (3) a magnetic layer formed of a mixed material of a magnetic material and a photothermal conversion material, and (4) a magnetic layer on a transparent substrate having a guide groove formed on one side. (5) A heat-insulating layer is provided between a transparent substrate having a guide groove formed on one side and a thin film carried on the transparent substrate, (6) On the outer surface of the magnetic layer, the Also Ku even either one is formed
And the like can be used. In addition, a plurality of sets of optical heads, magnetic heads or magnets are respectively arranged in a predetermined array in different radial areas of a magnetic disk, and information is recorded, reproduced, and erased simultaneously in a plurality of information recording areas on the magnetic disk. If they can be performed independently, the effective signal transfer rate can be further improved.

[0012]

According to the above-described recording / reproducing method, since the magnetic disk is used as the information recording medium, it is possible to construct a recording / reproducing system which is inexpensive and has excellent long-term storability of information. Also,
Since the guide groove is formed on the magnetic disk and the tracking is performed by the optical means, finer and more precise tracking control is possible, and the signal recording capacity can be increased. Further, since the signal is recorded or erased while the temperature of the magnetic layer is raised by the laser beam, the signal can be recorded or erased at a high speed with a smaller magnetic field, and as a result, the effective signal transfer rate is increased. it can. In addition, signal overwriting is possible, so
The signal transfer rate can be further increased as compared with the conventional magnetic recording / reproducing method.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of a magnetic recording / reproducing method according to the present invention will be described with reference to FIGS. FIG. 1 is a block diagram of a magnetic recording / reproducing apparatus for executing the magnetic recording / reproducing method of the present embodiment, FIG. 2 is an enlarged cross-sectional view of a main part of FIG. 1, and FIGS. 3 to 9 are diagrams of a magnetic disk applied to information recording / reproducing. It is sectional drawing which illustrates a film structure.

As shown in FIGS. 1 and 2, a magnetic recording / reproducing apparatus for executing the magnetic recording / reproducing method according to the present invention comprises a magnetic disk 1 and an optical head 2 arranged on one side of the magnetic disk 1. It is composed of the optical head 2 and the magnetic head 3 arranged on the opposite side of the magnetic disk 1. As the optical head 2, the optical head that has been conventionally applied to an optical disk system can be used as it is, except that an optical system for signal reproduction is unnecessary.
As the magnetic head 3, the one conventionally used in the magnetic recording / reproducing system can be used as it is.
However, in the present system, it is possible to set the track width to the micron order or the submicron order, and accordingly, the smaller the gap width is, the more preferable.

As the magnetic disk 1, those exemplified in FIGS. 3 to 9 can be used.

The magnetic disk 1 of FIG. 3 has a guide groove for tracking the optical head 2 and the magnetic head 3 on one surface.
A transparent water-proof film 14, a transparent heat insulating film 15, and a light-reflective magnetic film 16 are laminated in this order on the pattern forming surface of the transparent substrate 13 on which 11 is formed in a fine uneven shape. Become. A resin material such as polycarbonate or polymethylmethacrylate is particularly suitable as the transparent substrate material. An inorganic material such as SiO ₂ is particularly suitable for the transparent water-proof film 14. An inorganic material such as SiN or a mixture of SiO ₂ and SiN is particularly suitable for the transparent heat insulating film 15. As the magnetic film 16,
(1) γ-Fe ₂ O ₃ powder, Co-containing Fe ₂ O ₃ powder, Fe ₃ O ₄ powder, Co-containing Fe ₃ O ₄ powder, F
e powder, Co powder, magnetic powder such as Fe-Ni alloy powder applied with a binder and an organic solvent and dried,
(2) Co, Fe, Ni, Co-Ni alloy, Co-Cr
Alloy, Co-P alloy, Co-Ni-P alloy, Al-Co
Vacuum-deposited ferromagnetic materials such as alloys and Al-Ni-Co alloys. (3) Main components are rare earth elements such as Tb, Dy, Gd, and Hf and transition elements such as Co, Fe, Ni, and Cr. For example, a spontaneously magnetized ferromagnetic perpendicularly magnetized film such as an amorphous alloy can be used. If necessary, a lubricity protective film made of a mixed solution of a resin adhesive such as epoxy and a lubricant such as alumina or carbon (graphite powder) may be applied on the magnetic film 16.

In the magnetic disk 1 shown in FIG. 4, a transparent water-proof film 14, a transparent heat insulating film 15, and a reflective film 17 are formed on the pre-format pattern forming surface of the transparent substrate 13 similar to the above.
And the magnetic film 16 are laminated in this order. As a material for the reflective film, it is inexpensive, and therefore, alumite, aluminum whose surface is anodized, or Ti.
-Al etc. are especially suitable. Others are shown in Figure 3.
Since it is the same as the embodiment described above, the description thereof will be omitted to avoid duplication.

The magnetic disk 1 shown in FIG. 5 is formed by laminating a reflective film 17 and a magnetic film 16 in this order on a preformat pattern forming surface of a transparent substrate 13 similar to the above. Materials and the like suitable for each part are the same as those in the embodiment of FIG. 4, and therefore the description thereof is omitted to avoid duplication.

In the magnetic disk 1 of FIG. 6, a transparent water-proof film 14, a reflective film 17, a magnetic film 16, and a lubricity protective film 18 are formed on the pre-format pattern forming surface of the transparent substrate 13 similar to the above. Are laminated in this order. As the material for the lubricating protective film, as described above, a mixed solution of a resin adhesive such as epoxy and a lubricant such as alumina or carbon can be used. Others are shown in Figure 4.
Since it is the same as the embodiment described above, the description thereof will be omitted to avoid duplication.

In the magnetic disk 1 of FIG. 7, a transparent water-proof film 14, a magnetic film 16, and a reflective film 17 are laminated in this order on the pre-format pattern forming surface of the transparent substrate 13 similar to the above. Become. For materials suitable for each part,
Since it is the same as the embodiment of FIG. 4, description thereof is omitted to avoid duplication.

The magnetic disk 1 shown in FIG. 8 has a transparent water-proof film 14, a photothermal conversion layer 19, and a magnetic film 16 on the pre-format pattern forming surface of the transparent substrate 13 similar to the above.
And the reflective film 17 are laminated in this order. Examples of the light-heat conversion layer material include organic dye materials such as cyanine dyes and phthalocyanine dyes, Te, Bi, Te-Se-Pb alloys,
A thin film such as an Au-Sn alloy can be used.
The other points are the same as those of the embodiment of FIG. 4, and therefore the description thereof is omitted to avoid duplication.

In the magnetic disk 1 shown in FIG. 9, a transparent water-proof film 14, a transparent photothermal conversion layer 19, a reflective film 17, and a magnetic film 16 are formed on the pre-format pattern forming surface of the transparent substrate 13 similar to the above. And the protective film 18 are laminated in this order. Suitable materials and the like for the respective parts are the same as those in the embodiment shown in FIG. 8, and therefore their explanations are omitted to avoid duplication.

As shown in FIG. 1, the magnetic disk 1 shown in FIGS. 3 to 9 is formed in a disk shape having a spindle hole 1a at the center thereof. The guide groove 11 is formed in a spiral shape or a concentric shape concentric with the spindle hole 1a. Address signal
Preformatted signals such as
It is recorded in the form of.

As shown in FIG. 1, the magnetic disk 1 is mounted on a turntable 5 which is a medium drive unit of a drive device by inserting the tip of a rotary spindle 4 into a spindle hole 1a. The optical head 2 is arranged on the transparent substrate side of the magnetic disk 1, and the magnetic head 3 is arranged on the magnetic film 16 side of the magnetic disk 1. The distance between the disk surface of the magnetic disk 1 and the optical head 2, the contact pressure between the disk surface of the magnetic disk 1 and the magnetic head 3, and the relative position between the optical head 2 and the magnetic head 3 are determined by the magnetic disk 1. When it is mounted on the turntable 5, it is mechanically adjusted to a predetermined value. That is, the distance between the disk surface and the optical head 2 is adjusted to be near the focal length of the optical head 2, and the disk surface and the magnetic head 3 are adjusted.
The contact pressure with is adjusted to a predetermined value by a gimbal spring (not shown) on which the magnetic head 3 is mounted. Also,
The optical head 2 and the magnetic head 3 are positioned so that the gap portion of the magnetic head 3 is arranged on the optical axis of the optical head 2. The optical head 2 and the magnetic head 3 are integrally attached to the head frame 73, and are moved by the same amount in the same direction according to the rotation amount and the rotation direction of the feed screw 70 that is rotationally driven by the motor 72. . The motor 72 is controlled by a head feed control signal transmitted from a controller (not shown). Signals are exchanged between the optical head 2 or the magnetic head 3 and a control device (not shown) through the signal controller 74.

As shown in FIGS. 1 and 2, the magnetic recording / reproducing system of this embodiment irradiates a laser beam 6 from an optical head 2 along a guide groove (not shown) of the magnetic recording medium 1,
A tracking error signal is obtained from the reflected light to perform tracking of the optical head 2 and the magnetic head 3, and a desired information recording area is irradiated with a laser beam having a constant intensity for heating the magnetic layer 16 from the optical head 2 Information can be recorded by applying a pulse-shaped magnetic signal, which is larger than the coercive force of the magnetic layer 16 when the temperature is increased, from the head 3 to the magnetic layer 16. During recording, the magnetic layer 16
It is ideal to raise the temperature to near the Curie temperature or the compensation temperature, but even if it does not reach such a high temperature,
Since the coercive force of the magnetic layer 16 can be reduced as the temperature rises, the magnetic signal intensity required for recording information can be reduced as compared with the case of recording at room temperature as in a normal magnetic disk. Miniaturization of the magnetic head 3,
This is effective in lowering the output and eventually increasing the recording capacity of the magnetic recording medium 1. The optical head for the desired information recording area is
The position of the magnetic head and the magnetic head is magnetic on the magnetic disk.
Preformatted signal written in
This is done by detecting.

In reproducing information, the optical head 2 and the magnetic head 3 are tracked by the above-described method, the magnetic head 3 is positioned in a desired information recording area, and the signal from the area is magnetically read. Can be done with.

Information is erased by the optical head 2 by the above method.
While tracking the magnetic head 3 and irradiating a desired information recording area with a laser beam of a constant intensity for raising the temperature of the magnetic layer 16 from the optical head 2, the coercive force of the magnetic layer 16 at the time of raising the temperature from the magnetic head 3 This can be achieved by applying a large magnetic signal in the erasing direction to the magnetic layer 16.

Next, similar to the magnetic recording / reproducing method according to the above-mentioned embodiment, magnetic recording / reproducing is carried out in which information is recorded on the magnetic disk by magneto-optical means and information is reproduced from the magnetic disk by magnetic means. Another example of the method is shown in FIG.
It will be described with reference to FIG. As shown in FIG.
In the magnetic recording / reproducing system of the present example, first and second magnets 21 and 22 having polarities opposite to each other are arranged on the magnetic layer 16 formation surface side of the magnetic disk 1, and
Through the magnetic disk 1, the magnet 21 on the opposite side,
22. First and second optical heads (objective lenses) 2a and 2b are arranged at positions facing 22 respectively, and a magnetic head 3 is arranged outside the positions where the first and second magnets are arranged. I will do it. In FIG. 10, 23 is a laser light source, 2
4 is a beam splitter, 25 is a mirror, and 26 is an optical modulator. Laser beam 6 emitted from laser light source 23
Is split into two by the beam splitter 24. One of the split laser beams 6 is reflected by the mirror 25.
The magnetic disk 1 is guided to a first objective lens optical head 2a arranged on the upstream side in the rotation direction of the magnetic disk 1, and is irradiated onto the magnetic disk 1 as initialization light having a constant intensity from the first optical head 2a. The other of the split laser beams 6 is guided to the optical modulator 26 by the beam splitter 24, and intensity-modulated in a pulse shape by a predetermined information signal. The modulated light output from the optical modulator 26 is the second optical head 2 arranged on the downstream side in the rotation direction of the magnetic disk 1.
Then, the magnetic disk 1 is guided by the second optical head 2b as recording light.

As the magnetic disk 1, those exemplified in FIGS. 3 to 9 can be used.

As the magnets 21 and 22, those having a magnetic field strength capable of applying a magnetic field larger than the coercive force of the magnetic film 16 to the magnetic film 16 at the time of temperature rise are used. Specifically, (1) Co, Fe, Ni, Co-Ni
Alloy, Co-Cr alloy, Co-P alloy, Co-Ni-P
Alloy, Al-Co alloy, Al-Ni-Co alloy, etc. formed into a strip shape and perpendicularly magnetized, (2) γ-Fe ₂ O ₃
Powder, Co-containing Fe ₂ O ₃ powder, Fe ₃ O ₄ powder, Co
Containing Fe ₃ O ₄ powder, Fe powder, Co powder, Fe-Ni
Magnetic powder such as alloy powder coated with binder and organic solvent, dried and perpendicularly magnetized, (3) Co, F
e, Ni, Co-Ni alloy, Co-Cr alloy, Co-P
Alloy, Co-Ni-P alloy, Al-Co alloy, Al-N
(4) Tb-Fe-Co alloy, Tb-Fe-Co-, in which a ferromagnetic material such as an i-Co alloy is vacuum-deposited by using a vacuum deposition method or a sputtering method and perpendicularly magnetized,
Cr alloy, Tb-Fe-Co-Nb alloy, Gd-Dy-
(5) Spontaneous magnetization ferromagnetic perpendicular magnetization film made of an amorphous alloy containing a rare earth element and a transition element as a main component, such as an Fe-Co alloy and a Tb-Gd-Fe-Co-Cr alloy.
It is possible to use a spontaneously magnetized ferromagnetic perpendicularly magnetized film similar to the above (4) in which the outer surface is coated with a corrosion resistant material such as Ni, Co, or Cr. Among these, since they can be formed into a thin shape, the above (2), (3), (4), (5)
Are particularly preferred.

The magnets 21 and 22 are set in strips along the radial direction of the magnetic disk 1. Its width is
50 from micron order or submicron order
Although it can be set to any value up to the order of mm, it is preferable to set the optical heads 2a and 2b and the magnets 21 and 2 when the magnetic disk 1 is mounted in the drive device.
In consideration of the positional deviation with respect to 2, the width is set to a width larger than a value obtained by adding the fluctuation width of the laser beam 6 from the length of the minimum magnetization domain to the variation width. The lengths of the magnets 21 and 22 are formed so as to cover at least the recording area of the magnetic disk 1. The magnets 21 and 22 do not necessarily have to be formed in a continuous shape, and fine magnets 21 and 22 may be arranged in a straight line. In this case, the length of each of the fine magnets 21 and 22 can be made larger than the track pitch.

The magnets 21 and 22 are preferably arranged as close to the disk surface as possible so that the surfaces of the magnets 21 and 22 are opposed to the disk surface with a desired narrow interval when the disk rotates. It is used by adjusting the height of the magnet mount 27 or the thickness (film thickness) of the magnets 21 and 22. The magnetic disk 1
A smooth coating having excellent abrasion resistance and abrasion heat resistance is applied to the magnet facing surface of the magnet, and a coating having excellent lubricity and abrasion resistance is also formed on the surfaces of the magnets 21 and 22. The magnets 21 and 22 can be brought into sliding contact with the disk surface through the interposition.

In this magnetic recording / reproducing method, the optical head 2a is used.
A laser beam having a signal reproduction level is emitted from the optical disk 1 along the guide groove 11 of the magnetic disk 1, and a tracking error signal is obtained from the reflected light to perform tracking of the optical heads 2a and 2b, and a desired information recording area is formed. In addition, the coercive force of the magnetic layer 16 is set to the first portion at the portion facing the first magnet 21 arranged on the upstream side in the rotation direction of the magnetic disk 1.
The laser beam of a constant intensity required to reduce the intensity of the magnetic field applied from the magnet 21 of FIG.
Is irradiated from the optical head 2a to initialize the magnetic layer 16 in the relevant portion. Further, the laser beam emitted from the optical head 2b is positioned on the initialized track and at a portion facing the second magnet 22 arranged on the downstream side in the rotation direction of the magnetic disk 1, and the magnetic layer 16 is An optical head 2b emits a laser beam whose intensity is modulated in a pulse shape having a magnitude necessary to reduce the coercive force lower than the magnetic field intensity applied from the second magnet 22.
Information can be recorded by irradiating from. That is, the second
The direction of magnetization of the magnet 22 of the first magnet 2 is
The magnetic field strength of the second magnet 22 is opposite to the direction of the magnetization of No. 1 and is adjusted to a magnitude capable of applying a magnetic field larger than the coercive force of the magnetic film 16 to the magnetic film 16 at the time of temperature rise. Therefore, the temperature rising portion by the second optical head 2b (the portion of the irradiation pattern of the laser beam shown by the broken line in FIG. 11 which is irradiated with the high level laser beam) is selectively irradiated by the second magnet 22. The magnetization direction is reversed and a signal is recorded on the magnetic film 16.

Information can be reproduced by tracking the magnetic head 3 by the method described above, positioning the magnetic head 3 in a desired information recording area, and magnetically reading a signal from the area.

Further, in erasing information, while the optical head 2a is being tracked by the above-mentioned method, it opposes the first magnet 21 which is a desired information recording area and is arranged on the upstream side in the rotation direction of the magnetic disk 1. This can be performed by irradiating a portion of the magnetic layer 16 with a laser beam of a constant intensity required to reduce the coercive force of the magnetic layer 16 below the magnetic field intensity applied from the first magnet 21.

According to this magnetic recording / reproducing method, precise alignment between the optical head and the magnetic head is unnecessary, so that the magnetic recording / reproducing apparatus can be easily assembled as compared with the magnetic recording / reproducing method according to the above-described embodiment. There is a feature that becomes.

In the example of FIG. 10, two optical heads 2 are used.
Although a and 2b are used, as shown in FIG. 12, one optical head 2 is arranged substantially in the middle of the two magnets 21 and 22, and a portion facing the first magnet 21 from the optical head and a first magnet 21. 2 in the part facing the magnet 22 of 2
It is also possible to irradiate the striped laser beams 6a and 6b. That is, the laser beam 6 emitted from the laser light source 23 is divided into two by the beam splitter 24, one is directly incident on the optical head 2 via the mirror 25, and the other is incident on the optical head 2 via the optical modulator 26. Incident. By doing so, it is possible to emit a laser beam of constant intensity and a laser beam of which intensity is modulated together from one optical head (objective lens) 2.

Specific examples of a magnetic recording / reproducing apparatus for executing the magnetic recording / reproducing method according to the embodiment will be described below with reference to FIGS.
It will be described based on 7.

<First Specific Example> FIGS. 13 and 14 are views showing the first example, and FIG.
3 is a cross-sectional view which is turned upside down, and FIG. 14 is a perspective view which is turned upside down and partially broken. In these figures, reference numeral 31
Indicates a disk cartridge, and the same reference numerals are displayed on the other portions corresponding to the above figures. The disk cartridge 31 includes a lower half 32, an upper half 33, a magnetic disk 1 rotatably housed in a space formed by joining these halves 32, 33, a lower half 32 and an upper half 33. A shutter 34 slidably attached along one side of the joined body of
Magnet mount 27 provided on the inner surface of the upper half 33
And magnets 21 and 22 provided on the surface of the magnet mount 27.

The lower half 32 and the upper half 33 are both formed in a shallow dish shape in which a joining wall 36 of a constant height is erected along the periphery of the three sides excluding the periphery of the side where the shutter 34 is attached. The shutter 34 is provided on the inner surface of the side portion on the mounting side.
A guide projection 37 for attaching a slider 35 fixed integrally with the slider 35 and holding the slider 35 slidably is formed. The height of the guide projection 37 is lower than the height of the joining wall 36. A window hole 38 extending from the vicinity of the periphery of the guide projection forming side to the vicinity of the periphery opposite to the guide projection formation side is formed in the central portion of the lower half 32 as viewed from the side of the shutter attachment side. A rotary spindle 4 for rotating the magnetic disk 1 through the hole 38, an optical head 2 for irradiating the magnetic disk 1 with a laser beam, and a magnetic head 3 for reading a signal from the magnetic disk 1.
Can be inserted. On the other hand, a magnet mount 27 is integrally provided in a portion from the substantially central portion of the inner surface of the upper half 33 to the vicinity of the periphery on the guide projection forming side, and the magnet 2 is mounted on the surface of the magnet mount 27.
1, 22 are provided.

The lower half 32 and the upper half 33 are, for example, ABS resin, AS resin, vinyl chloride resin, polypropylene resin, polycarbonate resin, polyacrylate resin, polymethylmethacrylate resin, polytetrafluoroethylene resin, and these resin materials. It can be formed by using a material in which a filler or carbon is mixed. Although the magnet mount 27 formed separately from the upper half 33 can be attached to the upper half 33, it is preferable to integrally form the magnet mount 27 with the upper half 33 in order to facilitate manufacturing.

The shutter 34 is formed in a flat plate shape capable of opening and closing a window 38, and a slider 35 for operating the shutter 34 from the outside is attached to one end thereof. The slider 35 is formed with two recessed grooves 39a, 39b facing each other, into which the guide projections 37 formed on the lower half 32 and the upper half 33 can be gently inserted.
The shutter 34 is stored in the disc cartridge 31,
Further, by inserting the guide projection 37 into the concave grooves 39a and 39b, the combined body of the shutter 34 and the slider 35 is slidably attached to the disc cartridge 31, and the shutter 34 is slidable on the inner surface of the lower half 32. Is set to.

A return spring (not shown) is stretched between the shutter 34 or slider 35 and the lower half 32. Therefore, unless the slider 35 is operated from the outside, the window hole 38 is closed by the shutter 34, and foreign matter such as dust is prevented from entering. When the shutter 34 is driven in the opening direction against the elastic force of the return spring, the window hole 38 is opened and the rotary spindle 4, the optical head 2 and the magnetic head 3 can be inserted into the disk cartridge 31. .

The shutter 34 and slider 35 are
It can be formed using a resin material, a ceramic material, a metal material (in particular, stainless steel), or the like. The shutter 34 and the slider 35 can be mechanically coupled to each other, which are separately formed, but it is more preferable that they are integrally molded to facilitate manufacturing.

In the magnetic recording / reproducing apparatus of this example, since the magnetic disk 1 is housed in the disk cartridge 31 and the magnets 21 and 22 are set on the inner surface of the disk cartridge 31, members for setting the magnets 21 and 22 are provided. The system is easy to design without the need for a separate one. Also,
Since the optical head 2 and the magnetic head 3 are disposed on both sides of the spindle hole 1a, recording or erasing of signals by the optical head 2 and the magnets 21, 22 and reproduction of signals by the magnetic head 3 are performed at the same time. It can be performed independently and has a characteristic that the effective transfer rate of signals is high.

<Second Specific Example> Next, a second specific example of the magnetic recording / reproducing apparatus in the example will be described.
This will be described with reference to FIGS. 15 is an exploded perspective view of the apparatus of this example, FIG. 16 is a perspective view seen from below, and FIG.
19 to 19 are explanatory views of the disc retainer. In FIGS. 15 and 16, reference numeral 41 indicates a disc retainer, and the same reference numerals are displayed in the other portions corresponding to the above figures.

As shown in FIGS. 15 and 16, in the magnetic recording / reproducing apparatus of this example, a disk holder 41 is provided at the center of the inner surface of the upper half 33, and the optical head 2 and the magnetic head 3 are adjacent to each other. It is characterized by being set. The disc retainer 41 is formed on a disc having a diameter substantially the same as that of the turntable 5 and is rotatably attached to the center of the inner surface of the upper half 33 with a material having magnetism at least on the disc facing surface.

As shown in FIG. 17, the disc retainer 41 has a recess 42 formed in the disc facing surface of the upper half 33 and a holding plate 43 for covering a part of the recess 42 in the front surface thereof. By gently mounting the mounting portion 44 of the disc retainer 41 in the space formed by the upper half 33 and the holding plate 43, the disc holder 41 can be rotatably mounted on the upper half 33. Further, as shown in FIG. 18, a through hole 45 having a diameter smaller than the diameter of the disc retainer 41 is formed in the upper half 33, and a mounting groove 46 of the shutter is formed in the disc retainer 41, and the shutter is provided in the attaching groove 46. It is possible to rotatably attach to the upper half 33 by gently incorporating the through hole portion of the. FIG. 17
18 and 18, reference numeral 47 in the figure denotes a ferromagnetic plate. Further, as shown in FIG. 19, a concave portion 42 is provided on the outer surface of the upper half 33, and a holding plate 43 for covering a part of the concave portion 42 is provided on the surface portion of the upper half 33 and the holding plate. By gently mounting the mounting portion 44 of the disc retainer 41 in the space constituted by 43,
It can be rotatably attached to the upper half 33. In FIG. 19, reference numeral 48 in the figure indicates a magnet.

In this example, the optical head 2 and the magnetic head 3 are set adjacent to each other. Therefore, it suffices to open the window hole 38 only in the lower half 32 from the substantially central portion to the vicinity of the periphery on the guide projection forming side. Since the other configurations are the same as those of the above-mentioned respective embodiments, the same reference numerals are given to the portions corresponding to the drawings showing the respective embodiments, and the description thereof will be omitted.

The magnetic recording / reproducing apparatus of this example has a shutter 3b.
When the rotary spindle 4 is opened and the rotary spindle 4 is inserted through the opened window hole 38, the rotary spindle 4 is inserted into the spindle hole 1a opened at the center of the magnetic disk 1, and the magnetic disk 1 is centered. Further, the magnetic disk 1 is placed on the turntable 5, and the surface of the magnetic disk 1 is positioned. Then, at this stage, a magnet (not shown) embedded in the tip of the rotary spindle 4 attracts the disc holder 41, and the magnetic disc 1 is clamped by the attraction force. Therefore, in the system of this example, since it is not necessary to provide a magnetic center hub on the magnetic disk 1, the structure of the magnetic disk 1 is simplified and when the clamp member of the magnetic disk 1 is set on the drive device side. In comparison, the drive device can be reduced in size, weight, and cost. Further, in the magnetic recording / reproducing apparatus of this example, the optical head 2 and the magnetic head 3 are set adjacent to each other. Therefore, when the optical head 2 and the magnetic head 3 are set on the upper and lower sides of the magnetic disk 1 via the magnetic disk 1. As compared with the above, the space required for setting the heads can be significantly reduced, and the mechanism for moving the heads up and down can be significantly simplified.

<Third Concrete Example> Next, a third concrete example of the magnetic recording / reproducing apparatus in the example will be described.
Description will be made with reference to FIGS. 20 to 22. 20 is a sectional view of the apparatus of this example, FIG. 21 is an exploded perspective view, and FIG. 22 is a perspective view of the upper half viewed from below. In these drawings, the reference numeral 51 indicates a center hub, and the same reference numerals are displayed in other portions corresponding to the above-mentioned drawings.

As shown in FIGS. 20 and 21, in the magnetic recording / reproducing apparatus of this example, a magnetic center hub 51 is set at the center of the magnetic disk 1, and a guide is provided from approximately the center of the lower half 32. A first window hole 38a for inserting the rotary spindle and the optical head 2 is formed in the vicinity of the periphery of the projection forming side, and is symmetrical with the first window hole 38a through the center of the upper half 33. On the side, magnetic head 3
A second window hole 38b for inserting a hole is opened. On the outer surface of the lower half 32 and the outer surface of the upper half 33, shutters 34a and 34b that are simultaneously opened and closed, respectively.
The first window hole 38 on the inner surface of the upper half 33.
Magnets 21 and 22 are provided in a portion facing a. In the apparatus of this example, the transparent substrate 13 is directed to the optical head 2 side, and the magnetic layer 16 is set to the magnets 21 and 22.
The disk cartridge 31 is housed in the drive device so as to face the magnetic head 3 side.

<Fourth Specific Example> Next, a fourth specific example of the magnetic recording / reproducing apparatus in the example will be described.
This will be described with reference to FIGS. 23 to 25. FIG. 23 is a perspective view of the apparatus of this example in an open state, FIG. 24 is a perspective view seen from below during assembly, and FIG. 25 is a sectional view during assembly. In these figures, parts corresponding to those in the previous figures are indicated by the same reference numerals.

As shown in FIGS. 23 and 24, in the magnetic recording / reproducing apparatus of this example, the disk cartridge 31 is configured to be openable / closable, and the magnetic disk housed in the disk cartridge 31 can be appropriately replaced. Is characterized by. On the inner surface of the lower half 32, a disk storage portion 61 is recessed in a substantially circular shape, and the magnetic disk 1 is held by a disk holding portion 62 provided on the outer peripheral portion of the disk storage portion 61. The left and right end portions 60a and 60b of the disk storage portion 61 are open to the side surface portion of the lower half 32, and the magnetic disk 1 can be easily grasped by inserting fingers from there.
Further, in a part of the lower half 32, a head hole extending in the radial direction of the magnetic disk 1 and a window hole 3 for inserting a rotary spindle are provided.
8 is opened, and the window hole 38 is formed on the outer surface of the lower half 32.
A shutter 34 for opening and closing is attached. Note that FIG.
Reference numeral 4 in FIG. 4 and FIG. 25 indicates a shallow recess for housing the shutter 34. On the other hand, a disc retainer 41 is provided at the center of the inner surface of the upper half 33, and the magnet 21,
22 is provided. As the disc holder 41,
The same ones as shown in FIGS. 17 to 19 can be used. In the system of the present example, information can be recorded, reproduced, and erased by inserting the optical head and the magnetic head through one window hole 38.

The magnetic recording / reproducing apparatus of this example has a lower half 32.
Since the upper half 33 and the upper half 33 are configured to be openable and closable so that the magnetic disk 1 can be replaced appropriately, a plurality of magnetic disks can be used in one disk cartridge 31. Therefore, the storage space for the magnetic disk 1 and the disk cartridge 31 can be reduced, and a large number of magnetic disks 1 can be stored in the storage space having a fixed capacity.

<Fifth Specific Example> Next, a fifth specific example of the magnetic recording / reproducing apparatus in the example will be described.
This will be described with reference to FIGS. 26 and 27. FIG. 26 is an exploded perspective view of the apparatus of this example, and FIG. 27 is a sectional view. In these figures, parts corresponding to those in the previous figures are indicated by the same reference numerals. The magnetic recording / reproducing apparatus of this example is characterized in that double-sided recording is possible.

As shown in FIGS. 26 and 27, the disk cartridge 31 applied to the apparatus of this embodiment has a lower half 3
2 and the window holes 18 of the same shape and size at the opposite positions of the upper half 33.
a and 18b are opened, and a shutter 34 that can be opened and closed independently on the inner surface of the lower half 32 and the inner surface of the upper half 33, respectively.
a and 34b are provided. Then, each shutter 34
In the part corresponding to the disk center of the inner surface of a, 34b,
The disk holders 41a and 41b similar to those shown in FIGS. 17 to 19 are rotatably attached, and at least a portion corresponding to the moving range of the optical head (not shown) has two magnets 22a each. , 23a, 2
2b and 23b are attached.

The disk cartridge 31 of this example is shown in FIG.
As shown in FIG. 7, when the lower shutter 34b is opened and the rotary spindle 4 is inserted through the opened window hole 38b, the rotary spindle 4 is inserted into the spindle hole 1a formed in the central portion of the magnetic disk 1, and the magnetic The disc 1 is centered. The magnetic disk 1 is a turntable 5
The magnetic disk 1 is placed on the magnetic disk 1 and is positioned in the surface direction. Then, when this stage is reached, the magnet 66 embedded in the tip of the rotary spindle 4 attracts the disc holder 41a, and the magnetic disc 1 is clamped by the attraction force. Therefore, by inserting the optical head 2 and the magnetic head 3 through the opening window 38b on the lower side, it becomes possible to record, reproduce, and erase information on the lower surface of the double-sided recording type magnetic disk 1. If the magnetic disk is turned upside down and mounted on the rotary spindle 4,
In the same manner as described above, it becomes possible to record, reproduce, and erase information on the other surface of the double-sided recording type magnetic disk 1.

[0059]

As described above, according to the present invention,
Since the magnetic recording medium having excellent chemical stability is used as the information recording medium, it is possible to construct a recording / reproducing system that is inexpensive and has excellent long-term storage stability of information. Further, since the guide groove is formed on the magnetic disk and the tracking is performed by the optical means, finer and more precise tracking control is possible, and the signal recording capacity can be increased.
Moreover, since the signal is recorded or erased while the temperature of the magnetic layer is raised by the laser beam, the signal can be recorded or erased at a high speed with a smaller magnetic field, and as a result, the device can be downsized and the power consumption can be reduced. A reduction and an increase in signal transfer speed can be realized.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a configuration of a magnetic recording / reproducing system according to a first embodiment.

FIG. 2 is an enlarged cross-sectional view of a main part of FIG.

FIG. 3 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 4 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 5 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 6 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 7 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 8 is a cross-sectional view illustrating a film structure of a magnetic disk.

FIG. 9 is a cross-sectional view illustrating the film structure of a magnetic disk.

FIG. 10 is a diagram illustrating the configuration of a magnetic recording / reproducing system according to a second example.

FIG. 11 is a graph showing an irradiation pattern of a laser beam.

FIG. 12 is a structural explanatory view showing a modification of the magnetic recording / reproducing system in the second example.

FIG. 13 is a vertical cross-sectional view showing a first example of a disc cartridge.

14 is a partially cutaway perspective view of the disc cartridge of FIG. 13. FIG.

FIG. 15 is an exploded perspective view showing a second example of the disc cartridge.

16 is a perspective view of the disc cartridge of FIG. 15 seen from below.

FIG. 17 is a sectional view showing a first example of a disc retainer.

FIG. 18 is a sectional view showing a second example of the disc retainer.

FIG. 19 is a sectional view showing a third example of the disc retainer.

FIG. 20 is a sectional view showing a third example of a disk cartridge.

21 is an exploded perspective view of the disc cartridge shown in FIG. 20. FIG.

FIG. 22 is a perspective view of the upper half as viewed from below.

FIG. 23 is a perspective view showing a fourth example of the disc cartridge when it is developed.

FIG. 24 is a perspective view of the disc cartridge of FIG. 23 as seen from below.

25 is a cross-sectional view of the disc cartridge of FIG. 23.

FIG. 26 is an exploded perspective view showing a fifth example of a disc cartridge.

27 is a sectional view of the disc cartridge shown in FIG. 26. FIG.

[Explanation of symbols]

1 magnetic disk 2 Optical head 3 magnetic head 4 rotating spindle 5 turntable 6 laser beam 11 guide groove 13 Transparent substrate 16 Magnetic layer 21,22 magnet 27 Magnet mount 31 disk cartridge

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Claims (5)

(57) [Claims] 1. A magnetic recording / reproducing method for recording / reproducing information using a magnetic recording / reproducing apparatus including a magnetic disk having a tracking guide groove and a magnetic layer as an information recording layer, an optical head and a magnetic head. At the time of recording information, the pre- recorded magnetically recorded on the magnetic disk.
The format signal is detected to detect the optical head and magnetic field.
The magnetic layer is positioned at a desired area, the laser beam is irradiated from the optical head to a desired information recording area on the magnetic disk to raise the temperature of the magnetic layer, and the magnetic layer is heated from the magnetic head. A pulsed magnetic signal larger than the coercive force of the magnetic field is applied to the magnetic layer, and at the time of reproducing information, the pre- recorded magnetically written on the magnetic disk.
The optical head and magnetic head are detected by detecting the format signal.
A magnetic recording / reproducing method characterized in that a magnetic field is positioned in a desired area and a signal from the area is magnetically read. 2. A have your <br/> the magnetic recording and reproducing method according to claim 1, before Symbol the laser beam irradiated from the optical head to the guide grooves to obtain a tracking error signal from the reflected light,
A magnetic recording / reproducing method, characterized in that the optical head and the magnetic head are tracked. 3. The magnetic recording / reproducing method according to claim 1, wherein an optical head and a magnetic head which are arranged to face each other with the magnetic disk in between are used. 4. The magnetic recording / reproducing method according to claim 1, wherein an optical head and a magnetic head arranged adjacent to one side of the magnetic disk are used. 5. The magnetic recording / reproducing method according to claim 1, wherein the preformatted signal includes a sector address.
A magnetic recording / reproducing method including a signal .