JP3361336B2 - Information recording and playback system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an information recording medium having a magnetic material film and information recorded on the magnetic material film magnetically transferred to a signal transfer element to obtain a magnetic Kerr effect or a Faraday effect. The present invention relates to an information recording / reproducing system including an optical reading head for optical reading.

[0002]

2. Description of the Related Art A magneto-optical disk has been put into practical use as an information recording medium of high recording density capable of repeatedly recording and erasing information. Magneto-optical discs have a guide groove of a laser beam on one side and a transparent substrate preformatted in the form of fine irregularities for recording, reproducing, and erasing information required for information, for example, a rare earth-transition metal perpendicular magnetization film. A typical magnetic material film is carried, and a high power recording laser beam is irradiated along the guide groove to heat the magnetic material film to a temperature near its Curie temperature while recording in the temperature rising portion. Information is recorded by applying an external magnetic field in this direction and orienting the magnetization of the temperature rising portion in the recording direction. When the magnetic film on which information is recorded by such a method is irradiated with a reproducing laser beam of low power linearly polarized light, the magnetic Kerr effect or the Faraday effect causes a change in the direction of magnetization of the magnetic film. By utilizing the fact that the plane of polarization of the reflected light from the magnetic film rotates (the rotation angle is called the Kerr rotation angle), information is reproduced. Information is erased by irradiating a high-power erasing laser beam along the guide groove, while raising the temperature of the magnetic film to near its Curie temperature, applying an external magnetic field in the erasing direction to the temperature raising portion, This is performed by aligning the magnetization direction of the temperature rising portion with the erasing direction.

In a magneto-optical disk for recording, reproducing, and erasing information based on such a principle, the magnetic film is required to have a variety of characteristics such as excellent recording sensitivity and reproducing sensitivity. It However, such an ideal magnetic material has not been developed yet. Therefore,
Conventionally, a magnetic material having a good balance between recording sensitivity and reproducing sensitivity is used as an information recording film, and the reflectivity and Kerr rotation angle of the magnetic film are insufficient, and thus CN which is proportional to the product of the reflectance and the Kerr rotation angle is used. In order to compensate for the lack of the value, a reflective film made of a high-reflectance material is formed on the magnetic film, and a reproducing laser beam is multiply reflected between the transparent substrate and the magnetic film and / or the magnetic film and the reflective film. It is generally practiced to deposit an enhancement film for increasing the apparent Kerr rotation angle. Furthermore, in order to protect each of the above films from chemical influences and mechanical shocks, a protective film covering each of the above films is generally provided, and when a resin substrate is used as the transparent substrate, In order to protect the resin substrate from thermal influences during operation (especially during recording or erasing), silicon oxide (eg SiO 2) is formed on the surface of the resin substrate on which the preformat pattern is formed.
It is common practice to provide a heat insulating layer composed of ₂ ).

Therefore, in the conventional magneto-optical disk,
Since a magnetic material having a good balance between recording sensitivity and reproducing sensitivity must be selected as the information recording film, there are problems that the range of material selection is narrow, the material cost is high, and the quality control of the product is difficult. is there. In addition, since the magnetic film, the enhance film, the reflective film, and the like must be laminated in multiple layers, the film forming process (usually, these films are formed by a vacuum film forming method such as sputtering) is complicated. Therefore, there is also a problem that mass productivity deteriorates and the manufacturing cost increases.

By the way, in the technical field of magnetic disk devices and magnetic tape devices, as shown in FIG. 49, a perpendicular magnetization film is formed on the surface of the transparent substrate 3 so as to face the magnetic film 2 of the magnetic recording medium 1. An optical head 9 having a signal transfer element 6 in which a garnet thin film 4 and a dielectric film 5 are sequentially laminated, and an objective lens 8 for focusing linearly polarized light 7 on the garnet thin film 4 from the transparent substrate 3 side. There is a technique in which the magnetic signal recorded in the magnetic film 2 of the magnetic recording medium 1 is magnetically transferred to the gate thin film 4 and is optically read by utilizing the Kerr effect or the Faraday effect. Known from the past. A technique related to this is disclosed in, for example, JP-A-54-59915 and JP-A-56-101.
657, JP-A-56-117345, IEICE Transactions vol. j67-c, No11, 871
-878, 1984, 15 pA-9, etc., of the Japan Society for Applied Magnetics, Academic Summary (November 1984).

[0006]

As described above, in the magneto-optical disk, simplification of the film structure, simplification of the manufacturing process, and reduction of the manufacturing cost are one of the most important technical problems. . Even if the head device according to the above-mentioned known example is applied to the magneto-optical disk, the film structure of the magneto-optical disk cannot be simplified as it is, and further the manufacturing process of the magneto-optical disk and the manufacturing cost cannot be reduced. However, if the reflection film and the enhancement film are provided on the side of the perpendicular magnetization signal transfer element of the head device, these reflection film and the enhancement film provided on the side of the magneto-optical disk are not needed, and the film structure of the magneto-optical disk is significantly improved. Can be simplified to Further, since the magneto-optical disk is required only to have characteristics such as good recording sensitivity and capable of holding a large recording magnetic field,
The selection range of the magnetic recording material that is the information recording film can be expanded. Therefore, improvement in mass productivity of the magneto-optical disk and reduction in manufacturing cost can be expected.

Further, in the magneto-optical disk, a means for guiding the head device along the track, such as a guide groove or a wobble pit, is an essential requirement in order to increase the information recording density. Of course, the head device according to the known example does not include any device for detecting the guide groove or the like formed on the magneto-optical disk and performing tracking control of the head device. Therefore, it is not possible to read information from the magneto-optical disk by simply combining the known magneto-optical disk and the head device including the signal transfer element.

In the above description, a magneto-optical disk is taken as an example, but an idea of forming a head guide means such as a guide groove has also been proposed for a magnetic disk in order to increase the recording density. Information cannot be read from the magnetic disk even if the head device including the signal transfer element is applied as it is.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a head guiding means such as a guide groove without a film for increasing a reproduction CN value such as a reflecting film or an enhancing film. It is to provide a recording / reproducing system capable of reproducing information from an information recording medium having the above.

[0010]

In order to achieve the above-mentioned object, the present invention provides an information recording / reproducing system including a magnetic film.
And an information recording medium having the magnetic recording medium and the magnetic recording medium.
And magnetically transfer the information recorded on the magnetic film.
A signal transfer element and an enhancer provided in the signal transfer element.
A reproducing laser on the signal transfer element and the reflection film and the reflection film.
Beam irradiation, magnetic Kerr effect or Faraday effect
The information signal transferred to the signal transfer element by using
Read-out and servo control on the information recording medium
Laser beam for tracking and focusing
Configuration including an optical head that generates a servo signal for
did.

[0011]

[0012]

[0013]

[Function] If a reflection film or an enhancement film necessary for enhancing the reproduction sensitivity is formed on the side of the perpendicular magnetization signal transfer element of the optical head, the reflection film and the enhancement film having high thermal conductivity are not required on the side of the magneto-optical disk. Therefore, the film structure of the magneto-optical disk can be simplified. Further, the magneto-optical disk is required only to have characteristics such as good recording sensitivity and ability to hold a large recording magnetic field. Therefore, for example, a light reflecting film having a low thermal conductivity should be selected and used, or an information recording film. It is possible to improve only the information recording sensitivity by expanding the selection range of the magnetic material of the magnetic recording material. Therefore, from the above, it is possible to improve the recording characteristics and mass productivity of the magneto-optical disk and reduce the manufacturing cost.

Further, if the servo control laser beam is emitted from the optical head together with the reproducing laser beam and the optical head is servo-controlled using the reflected light signal from the information recording medium, a guide groove or the like is generated. Information can be recorded, reproduced, and erased on the high-density recording information recording medium in which the head guide means is preformatted.

Further, if the signal transfer element is formed separately from the head, the head structure can be simplified and the operating characteristics of the head can be improved.

[0016]

【Example】

<First Embodiment> A first embodiment of the present invention will be described with reference to FIGS. The information recording / reproducing system of this example is characterized by having a configuration suitable for a magneto-optical disk device.

The information recording / reproducing system of this example, as shown in FIG. 4, includes a magneto-optical disk 11 and the magneto-optical disk 1.
A spindle motor 12 for rotationally driving 1; a magnetic head 13 and an optical head 14 arranged opposite to each other via a magneto-optical disk 11; and an information source 15 for supplying a recording signal to the magnetic head 13 and the optical head 14. A signal reproducing circuit 16 for reproducing the information signal a from the reflected light signal of the magneto-optical disk 11, a tracking error signal detection circuit 17 for detecting a tracking error signal b from the reflected light signal of the magneto-optical disk 11, and a magneto-optical disk A focus error signal detection circuit 18 that detects a focus error signal c from the reflected light signal of 11, a tracking servo signal generation circuit 19 that outputs a tracking servo signal d corresponding to the output signal of the signal detection circuit 17, and a signal detection circuit 18
A focus servo signal generation circuit 20 for outputting a focus servo signal e corresponding to the output signal of the above, and an actuator 21 for driving the optical head 14 in the direction in which the error signals b and c become zero according to the servo signals d and e. And a controller 22 for controlling each of the above circuits.

As shown in FIG. 6, the magneto-optical disk 11 is basically provided with a guide groove 31 of the optical head 14 and a prepit row 32 representing a preformat signal necessary for recording, reproducing and erasing information on one side. The transparent substrate 33 pre-formatted in the form of fine irregularities, the magnetic film (magneto-optical recording film) 34 provided on the surface of the transparent substrate 33 on which the pre-format pattern is formed, and the magnetic film 34 are chemically affected. And a protective film 35 for protecting it from mechanical shock.

The guide grooves 31 and the prepit rows 32 are arranged in a spiral shape or a concentric shape around the rotation center of the magneto-optical disk 11. The guide groove 31 and the pre-pit row 32 can be arbitrarily arranged as needed. For example, as shown in FIGS. 7A and 7B, a prepit row 32 is formed on a guide groove 31 arranged in a spiral shape or a concentric shape.
8A and 8B can be formed by overlapping.
As shown in, the pre-pit row 3 is provided between the two guide grooves 31.
It is also possible to arrange two. 9 (a) and 9 (b)
As shown in FIG. 3, head guide wobble pits 31a and 31b, which replace the guide groove 31, are provided in a slightly eccentric manner on the inner and outer circumference sides of the magneto-optical disk 11 with respect to the spiral or concentric tracks. Pre-pit rows 32 may be arranged on the track. In addition, although not shown, a signal for guiding the optical head can be embedded in a pre-pit row representing an information signal, for example, as in a known compact disc (CD). Instead of the above structure, the magneto-optical disk 11 having only the guide groove 31 without the prepit row 32 is manufactured,
It is also possible to adopt a configuration in which the preformatted signal is written in the magnetic film 34 by a photothermal-magnetic means.

Since the magneto-optical disk 11 has a film structure in which the enhancement film and the reflection film are omitted as compared with the conventional magneto-optical disk, it has an advantage that it can be easily manufactured at low cost. Further, since the magnetic material film 34 can be formed of a magnetic material having arbitrary reproducing characteristics, good recording sensitivity and capable of holding a large recording magnetic field, it is possible to widen the selection range of the magnetic material and design. In addition to being easy, the mass productivity of the magneto-optical disk can be improved and the manufacturing cost can be reduced from this point as well.

Incidentally, the magneto-optical disk 11 may be laminated with another film if necessary. Examples thereof are illustrated in FIGS. 10 to 13. In the example of FIG. 10, the transparent substrate 3
On the pre-format pattern forming surface of No. 3, for example, SiO
_A heat insulating film 36 made of an inorganic dielectric such as ₂ ; a magnetic film 34 being a magneto-optical recording film; and a protective film 37 made of a wear-resistant resin material mixed with a lubricant or filler such as graphite. The films are sequentially stacked. In the example of FIG. 11, the same heat insulating film 36, the magnetic film 34, and a lubricant such as graphite or a wear resistant filler are mixed on the pre-format pattern forming surface of the transparent substrate 33 on the outermost surface. The non-heat conductive light reflecting film 38 is sequentially stacked. 12
In the above example, on the surface of the transparent substrate 33 on which the preformat pattern is formed, the same heat insulating film 36, magnetic film 34, and
A light reflection film 39 and a protective film 37 similar to FIG. 10 are sequentially stacked. In the example of FIG. 13, the same heat insulating film 36 as described above is formed on the preformat pattern forming surface of the transparent substrate 33.
A magnetic film 34, an in-plane magnetized film 40 that exerts an exchange coupling force on the magnetic film 34, a light-reflective auxiliary magnetic film 41 for promoting magnetization reversal of the magnetic film 34, A protective film 37 similar to the above is sequentially laminated. These magneto-optical disks 11 are suitable for a recording / reproducing system of a type in which a transparent substrate is made of a resin material and the magnetic head 13 is brought into contact with the protective film 37 to slide.

On the rotary shaft 51 of the spindle motor 12,
As shown in FIG. 4, a turntable 52 for mounting and rotating the magneto-optical disk 11 is fixed to a portion slightly below the tip of the turntable 52, and a magnet 53 for fixing the disk is provided on the inner peripheral side of the turntable 52. Is buried.
On the other hand, at the center of the magneto-optical disk 11, as shown in the figure, a center hole 54 into which the tip of the rotary shaft 51 can be inserted.
And a center hub 56 made of a magnetic material and having a spindle hole 55 concentric with the center hole 54.
Is attached. In the magneto-optical disk 11, the tip portion 51a of the rotating shaft 51 is inserted into the center hole 54,
By mounting the back surface on the turntable 52, the spindle motor 12 is detachably clamped. That is, the magneto-optical disk 11 is clamped by the attraction force acting between the magnet 53 and the center hub 56 made of a magnetic material, and the rotation driving in a predetermined rotation mode becomes possible.

As shown in FIG. 4, the magnetic head 13 and the optical head 14 are integrally connected by a frame 61, and the irradiation spot from the optical head 14 is always magnetic head 13.
Are arranged so as to face each other and move in the same direction on the radius of the magneto-optical disk 11 by the same amount. As shown in FIGS. 3 and 4, the optical head 14 includes two guide rails 62 that are set parallel to each other.
By rotating a feed screw 63, which is slidably attached to a and 62b, and is connected to a head feed motor (not shown), the magneto-optical disk 1 together with the magnetic head 13 is rotated.
1 is transferred in the radial direction.

As shown in FIGS. 4 and 5, the optical head 14 has, in front of the laser beam emission port 71, a first cylindrical body 74 in which a reproducing objective lens 72 and a signal transfer element 73 are housed. , A second objective lens 75 for recording is stored
It is set to be replaceable with the cylindrical body 76. These first
The second cylinders 74 and 76 are attached to the switching motor 77, and when the magneto-optical disk device is switched to the recording mode or the reproduction mode, by driving the switching motor 77, any one of them can be appropriately used. The cylindrical body can be set in front of the laser beam emission port 71.

As shown in FIGS. 1 and 2, the signal transfer element 73 includes a transparent substrate 81, and a first enhancement film 82 made of a dielectric material having a refractive index larger than that of the transparent substrate 81 and having an antireflection property. , For example, magnetic garnet thin film or Tb-Fe-
A magnetic signal transfer film 83 including a rare earth-transition metal based perpendicular magnetization film such as a Co alloy, and the first enhance film 8
A second enhancement film 84 made of a transparent material similar to 2,
The light reflection film 85 is made of a material having a high light reflectance with respect to the reproducing laser beam. The transparent substrate 81 of the signal transfer element 73 is formed in a size large enough to cover the entire opening of the first cylindrical body 74, and each thin film from the first enhancement film 82 to the light reflection film 85 of the signal transfer element 73 is formed. As shown in FIGS. 1, 3, and 14 (a) and 14 (b), it is formed in a rectangular shape, and its longitudinal direction is set in the radial direction of the magneto-optical disk 11. In the first cylindrical body 74,
A reproduction laser beam 86 and a servo control laser beam 87 emitted from a laser light source (not shown) and split by a beam splitter (not shown) (for example, a diffraction grating) are introduced through an optical polarizer. , The reproduction laser beam 86 is
The objective lens 72 focuses the magnetic signal transfer film 83 of the signal transfer element 73, and the servo control laser beam 8
7 is focused on the magnetic film 34 of the magneto-optical disk 11 by the objective lens 72 through the transparent portion 73a of the signal transfer element 73. 1, 3, and 14 (a),
In the example of (b), the reproducing laser spot 86 a is focused on the central portion of the magnetic signal transfer film 83, and is formed in each of the two guide grooves 31 running in parallel in the direction crossing the magnetic signal transfer film 83. Servo control laser spot 87a,
87b is in focus.

The reproduction laser beam 86 is applied to the signal transfer element 7
In order to focus on the magnetic signal transfer film 83 of No. 3, and to focus the servo control laser beam 87 on the magnetic layer 34 of the magneto-optical disk 11, the reproducing laser beam transmitting portion of the objective lens 72 and the servo control are used. The objective lens 72 must be designed so that the laser beam transmitting portion has a different focal length or depth of focus. In the optical head 14 of the type in which the two servo control laser beams 87 are focused on the magneto-optical disk 11 from both sides of the magnetic signal transfer film 83 as in the above-described embodiment, as shown in FIG. The rectangular portion 72a facing the magnetic signal transfer film 83 in the central portion of the objective lens 72 is designed to have a short focal length and both side portions 72b have long focal lengths. Further, the rectangular portion 72a may be designed to have a small depth of focus and the side portions 72b on both sides thereof to have a large depth of focus.

The magnetic signal transfer film 83 of the optical head 14
And the magnetic layer 34 of the magneto-optical disk 11 are arranged close to each other and exert a magnetic influence on each other.
In order to ensure that the information recorded on the magnetic recording layer 4 is transferred to the magnetic signal transfer film 83, and the information recorded on the magnetic layer 34 is not erased by the magnetic field generated from the magnetic signal transfer film 83, , So that the saturation magnetization and coercive force of the magnetic layer 34 are sufficiently higher than the saturation magnetization and coercive force of the magnetic signal transfer film 83.
3 and the magnetic characteristics of the magnetic layer 34 must be adjusted. Preferably, in the temperature range of 60 ° C. or lower, the saturation magnetization and the coercive force of the magnetic layer 34 are the magnetic signal transfer film 8.
Sufficiently higher than the saturation magnetization and coercive force of 3 is used. In order to record information with a low power laser beam, the Curie temperature of the magnetic layer 34 is preferably as low as possible, and a magnetic substance having a Curie temperature in the temperature range of 20 ° C to 300 ° C is used. It is more suitable.

FIG. 16 shows an example of a signal processing device provided in the optical head 14. As shown in this figure, the signal processing apparatus of this example includes an incident optical system 91 and an information signal reproducing system 9
2, a tracking control system 93, and a focus control system 9
4 and. The incident optical system 91 includes a laser light source 95.
And a laser beam 95a emitted from the laser light source 95
It is composed of a diffraction grating 96 that diffracts light to obtain a 0th-order diffracted light 86 and a 1st-order diffracted light 87, and a collimator lens 97 that makes the 0th-order diffracted light 86 and the 1st-order diffracted light 87 parallel light. The information signal reproducing system 92 includes a half mirror 98 that guides the reflected light from the magneto-optical disk 11, an analyzer 99, and a photodetector 100.
And a signal reproducing circuit 16. The tracking control system 93 includes a first beam splitter 101 provided between the half mirror 98 and an analyzer 99, a cylindrical lens 102, a photodetector 103, a tracking error signal detection circuit 17, and a tracking signal. It is composed of a servo signal generation circuit 19. The focus control system 94 includes a second mirror provided between the half mirror 98 and the analyzer 99.
The beam splitter 104, the photodetector 105, the focus error signal detection circuit 18, and the focus servo signal generation circuit 20. As described above, the optical head 14 of the present example is different from the conventional one except that the cylindrical bodies 74 and 76 are configured to be replaceable and the diffraction grating 96 is provided between the laser light source 95 and the collimator lens 97. Further, the optical disc device is configured similarly to that provided in the optical disc device.

FIG. 17 shows an example of a servo control actuator provided in the optical head 14. In this example, an actuator provided in the first cylindrical body 74 will be described as an example. The first cylindrical body 74 includes the signal transfer element 73.
And an inner cylinder 74b provided with a reproducing objective lens 72. A magnet 106 is provided in a part of the outer cylinder 74a, and an electromagnet is provided in a portion of the inner cylinder 74b that faces the outer cylinder 74a. 107 is attached. Therefore, by switching the polarity of the current applied to the electromagnet 107, the inner cylinder 74b (objective lens 72) can be moved back and forth with respect to the outer cylinder 74a fixed to the optical head body. Focus control is possible. In the inner cylinder 74b, the objective lens 72 has the magnetic body 1
08 is swingably supported, and a voice coil 109 is provided on the outer peripheral portion of the outer cylinder 74a. Therefore, by switching the polarity of the current applied to the voice coil 109, the objective lens 72 can be oscillated by an appropriate and appropriate amount with respect to the optical axis, and the optical head 14 can be tracking-controlled. The second cylinder 76 has the same configuration as that of the second cylinder 76 except that the recording / erasing objective lens 75 is provided on the outer cylinder. The operation of the signal processing device and the actuator will be described in detail below.

In the magneto-optical disk device of the above embodiment, the cylinder of the optical head 14 is switched to the second cylinder 76 for recording / erasing, and the output of the laser light source 95 incorporated in the optical head 14 is recorded. Switch to level, objective lens 7
By irradiating a pulsed recording laser beam which is signal-modulated by the signal from the information source 15 from 5 while applying a recording magnetic field from the magnetic head 13 to the irradiated portion,
Information is photothermally recorded on the land portion between the two guide grooves 31. In the above description, the information recording by the so-called light intensity modulation method has been described. However, while irradiating the recording laser beam having a constant intensity from the objective lens 75, the pulse shape modulated by the signal of the information source from the magnetic head 13 is used. It is also possible to perform information recording by a so-called magnetic field intensity modulation method of applying the recording magnetic field.

For erasing information, the magnetic head 13 is irradiated with the erasing laser beam having a constant intensity from the objective lens 75 while the cylinder of the optical head 14 is being switched to the second cylinder for recording / erasing 76. Can be performed by applying an erasing magnetic field.

Information is reproduced by switching the cylinder of the optical head 14 to the first cylinder 74 for reproduction and switching the output of the laser light source 95 built in the optical head 14 to the reproduction level. . Then, as shown in FIGS. 1 and 16, the laser beam 95a emitted from the laser light source is divided into a plurality of lines by the diffraction grating 96, and the 0th-order diffracted light 86 is transferred by the objective lens 72 to the magnetic signal transfer of the signal transfer element 73. The film 83 is focused and the magnetic signal transfer film 83 is irradiated with a light spot 86b. Since the magnetic signal transfer film 83 and the magnetic film 34 of the magneto-optical disk 11 are disposed in close proximity to each other, the signal 8 magneto-optically recorded on the magnetic film 34 of the magneto-optical disk 11 is formed on the magnetic signal transfer film 83.
6a is magnetically transferred. Therefore, by irradiating the magnetic signal transfer film 83 with linearly polarized light and detecting the change in the Kerr rotation angle of the reflected light with the analyzer 99 and the photodetector 100, the information signal transferred to the magnetic signal transfer film 83 is detected. Can be played. In this case, since the signal transfer element 73 is provided with the first and second enhancement films 82 and 84 and the light reflection film 85, neither the enhancement film nor the light reflection film is provided as the magneto-optical disk 11. Even if you use things
A large reproduction CN value can be obtained. Therefore, the layer structure of the magneto-optical disk 11 can be simplified, and the magneto-optical disk 1
1 can be reduced in manufacturing cost (see FIGS. 1 to 3).

At the time of information reproduction, tracking control and focus control of the optical head 14 are performed at the same time as the reproduction operation. In the tracking control of the optical head 14 at the time of reproducing information, as shown in FIGS. 1 and 2, the first-order diffracted light 87 is made adjacent to the magneto-optical disk 11 from the transparent portions 73a formed on both sides of the magnetic signal transfer film 83. Two light spots 87a, 87 are focused on the two guide grooves 31 respectively.
get b. Then, the tracking error signal b (see FIG. 4) is detected from the reflected light signal by the tracking error signal detection circuit 17, and the tracking servo signal generation circuit 19 generates the tracking servo signal d (see FIG. 4). This is performed by driving the optical head 14 by the actuator 21 in the direction in which the tracking error signal b becomes zero according to the signal d. In the focus control, the focus error signal c is detected from the reflected light signal by the focus error signal detection circuit 18, and the focus servo signal e is detected by the focus servo signal generation circuit 20.
(See FIG. 4) is generated, and the optical head 14 is driven by an actuator (see FIG. 17) in the direction in which the focus error signal c becomes zero according to the signal e.

Another example of the recording / reproducing system suitable for the magneto-optical disk device will be described below with reference to FIGS.

18 to 20 show modified examples of the shape of the signal transfer element 73, and FIGS. 21 to 23 show the reproducing objective lens 7.
It is a modification of the shape of 2. In the example of FIGS. 18A and 18B, the signal transfer element 73 is provided in a circular shape at the center of the cylindrical body 74. Then, the reproduction laser spot 86a is focused on the signal transfer element 73, and the servo control laser beam is emitted from the periphery thereof, and the servo control laser spots 87a, 87 are formed on the guide groove 31 of the magneto-optical disk 11.
It is configured to focus b. In the optical head 14 having the signal transfer element 73 of this example, as shown in FIG. 21, the objective lens 72 includes the signal transfer element 7 in the central portion.
The circular portion 72a facing 3 is short in focal length and the peripheral portion 72b is long in focal length.
It is also possible to design the circular portion 72a so that the focal depth thereof is small and the peripheral portion 72b thereof has a large focal depth. In the example of FIGS. 19A and 19B, the signal transfer element 73 is provided in a semicircular shape that covers a substantially half surface of the cylindrical body 74. Then, the reproduction laser spot 86a is focused on the signal transfer element 73, the servo control laser beam is emitted from the remaining transparent portion of the half surface, and the servo control laser spot 8 is formed on the guide groove 31 of the magneto-optical disk 11.
It is configured to focus 7a. In the optical head 14 having the signal transfer element 73 of this example, as shown in FIG. 22, in the objective lens 72, the semicircular portion 72a facing the signal transfer element 72 on the substantially half surface has a short focal length and the remaining half surface. The semi-circular portion 72b is designed to have a long focal length. It is also possible to design so that the semicircular portion 72a has a small depth of focus and the remaining semicircular portion 72b has a large depth of focus. 20 (a),
In the example of (b), the signal transfer element 73 is provided in a circular shape at a position offset from the center of the cylindrical body 74 in the track direction. Then, the reproduction laser spot 86a is focused on the signal transfer element 73, and the servo control laser beam is emitted from the surrounding crescent-shaped transparent portion to perform servo control on the guide groove 31 of the magneto-optical disk 11. It is configured to focus the laser spot 87a. In the optical head 14 having the signal transfer element 73 of this example, FIG.
As shown in FIG. 7, in the objective lens 72, the focal length of the circular portion 72a facing the signal transfer element 73, which is deviated in the track direction from the center of the cylindrical body 74, is short, and the surrounding crescent portion 72b is long. Is designed to be. It is also possible to design the circular portion 72a to have a small depth of focus and the crescent portion 72b to have a large depth of focus.

24 to 26 show modifications of the film structure of the signal transfer element 73. The signal transfer element 73 of FIG. 24 includes a heat insulating layer 88 made of SiO ₂ or the like on a transparent substrate 81,
The first enhancement film 82, the magnetic signal transfer film 83, the second
An enhancement film 84 and a light reflection film 85 are sequentially laminated. This film structure is particularly suitable for the signal transfer element 73 using a resin substrate as the transparent substrate 81. The signal transfer element 73 shown in FIG. 25 has an enhancement film 82 on a transparent substrate 81.
The magnetic signal transfer film 83 and the light reflection film 85 are sequentially laminated. The signal transfer element 73 of FIG. 26 is a transparent substrate 81.
A magnetic signal transfer film 83, an enhancement film 82, and a light reflection film 85 are sequentially laminated on top of this.

27 to 30 show modifications of the function switching structure of the optical head 14. In the above-described embodiment, the first cylindrical body 7 including the reproducing objective lens 72 and the signal transfer element 73.
4 and the second cylindrical body 76 having the recording / erasing objective lens 75 are exchanged, the function of the optical head 14 is switched to recording / erasing or reproduction.
In the optical head 14, the function of the optical head 14 is switched for reproduction by attaching the signal transfer element 73 to the laser beam emission port of the cylindrical body 74a having the shared objective lens 72a (state of FIG. 27). By removing the signal transfer element 73 from the laser beam emitting port of the cylindrical body 74a, the function of the optical head 14 is switched to recording / erasing. 27 and 28, reference numeral 1
Reference numeral 10 denotes a drive unit for supporting and driving the signal transfer element 73.

In the optical head 14 shown in FIGS. 29 and 30,
A head mount 112 is mounted on the guide rails 62a and 62b and the linear motor 111 provided in the radial direction of the magneto-optical disk 11, and a recording laser beam and a tracking laser beam are emitted onto the head mount 112. The first optical head 14a is attached.
Reference numeral 113 is a feed screw for moving the first optical head 14a in the radial direction of the magneto-optical disk 11.
The head mounting base 112 is integrally provided with an arm 114 having a U-shaped side surface.
The second optical head 14b for reproduction only having an objective lens and a signal transfer element incorporated therein and a magnetic head 13 as an external magnetic field for signal recording are provided at the tip of the magneto-optical disk 1.
1 are arranged and fixed in the radial direction.

At the time of reproducing information, as shown in FIGS. 29 and 30, the first and second optical heads 14a and 14b are arranged to face each other, and the tracking servo signal detected by the first optical head 14a is used. Based on these first and second
While the tracking control is performed on the optical heads 14a and 14b, the information signal recorded on the magneto-optical disk 11 is optically reproduced by the second optical head 14b. At the time of recording information, the feed screw 113 is driven to move the first optical head 14a to a position facing the magnetic head 13, and based on a tracking servo signal detected by the first optical head 14a, Tracking control is performed on both heads 14a and 13. Then, a recording laser beam is irradiated from the first optical head 14a to heat the magnetic film 34 of the magneto-optical disk 11 to a predetermined temperature, and a recording magnetic field is applied from the magnetic head 13 to the temperature rising portion. To record the information.

<Second Embodiment> Next, a second embodiment of the present invention will be described with reference to FIGS. 31 and 32. The information recording / reproducing system of this example is characterized in that it has a configuration suitable for a magnetic disk device using a magnetic disk having a magnetic layer for magnetically recording information at room temperature on a substrate as an information recording medium.

The information recording / reproducing system of this example, as shown in FIG. 31, includes a magnetic disk 11a and a magnetic disk 1a.
A spindle motor 12 that rotationally drives 1a, and a magnetic head 13 that is disposed opposite to each other with a magnetic disk 11a interposed therebetween.
And an optical head 14.

As shown in FIG. 32, the magnetic disk 11a has a guide groove 31 of the optical head 14 and information recording on one surface thereof.
A substrate 121 on which a pre-pit row 32 representing a pre-formatted signal necessary for reproduction and erasing is pre-formatted in the form of fine unevenness, a magnetic layer 122 provided on a pre-format pattern forming surface of the substrate 121, and a magnetic layer Body layer 1
22 and a slippery layer 123 provided on the surface. As the magnetic disk 11a, a so-called hard disk in which the substrate 121 is made of a hard material can be used, or a so-called flexible disk (floppy disk) in which the substrate 121 is made of a flexible material can be used. The magnetic layer 122 is made of, for example, iron oxide, chromium oxide, cobalt oxide, or iron,
Single components of transition metals such as cobalt, nickel, chromium and platinum, or alloys containing at least one component of these transition metals as a main component, oxygen or nitrogen containing substances such as these transition metals, ferrite, aluminum-nickel-cobalt alloy, bismuth Alloy, gadolinium, dysprosium,
A sputter-formed film or a vacuum-deposited formed film of an alloy of a rare earth element such as hafnium, terbium, neodymium, or germanium and a transition metal such as iron, cobalt, nickel, chromium, or platinum, or a magnetic substance selected from the above magnetic substance group. A mixed film of the powder and the binder is used.

As shown in FIG. 31, the magnetic head 13 and the optical head 14 are integrally connected by a frame 124, and are configured to move in the same direction on the radius of the magnetic disk 11a by the same amount. Has been done. The optical head 14 is
Two guide rails 62a and 62b set parallel to each other
It is slidably attached to the magnetic disk 11a and is rotated in the radial direction of the magnetic disk 11a by rotating a feed screw 63 connected to a head feed motor (not shown). As the magnetic head 13, it is possible to use a known one that has been conventionally used in a hard disk device, a floppy disk device, or the like. Further, as the optical head 14, as shown in FIG. 32, a cylindrical body 125 is provided on the side facing the magnetic disk 11a, and a signal transfer element 73 similar to that described in the first embodiment is provided therein.
Then, it is possible to use the one in which the reproducing laser beam is focused on the signal transfer element 73, and the objective lens 72 for focusing the tracking laser beam on the magnetic disk 11a is housed.

In the magnetic disk apparatus of this embodiment, the optical head 14 irradiates the magnetic disk 11a with a tracking laser beam to control the tracking of the optical head 14 and the magnetic head 13, while the magnetic head 13 is driven to perform magnetic control. An information signal is magnetically recorded or erased on the disk 11a at room temperature. Similarly, while the optical head 14 irradiates the magnetic disk 11a with a tracking laser beam to perform tracking control of the optical head 14 and the magnetic head 13, a reproducing laser beam is emitted from a laser light source (not shown) to the magnetic field of the signal transfer element 73. Focus on the signal transfer film 83,
The information signal of the magnetic disk 11a transferred to the magnetic signal transfer film 83 is optically read to reproduce the information signal.

Although the guide groove 31 and the prepit row 32 are pre-formatted on the magnetic disk 11a in the above-described embodiment, a head guiding signal and a pre-formatted signal are recorded on the magnetic disk 11a instead of such a configuration. It is also possible to record magnetically on the magnetic layer 122. In this case, the tracking of the optical head 14 and the magnetic head 13 and the reading of the preformat signal are performed by the magnetic head 13.

<Third Embodiment> Next, a third embodiment of the present invention will be described with reference to FIGS. The information recording / reproducing system of this example is characterized in that the signal transfer element is provided separately from the optical head.

33 to 35 are views showing a first example thereof, and as shown in FIGS. 33 and 34, the disk transfer table 1 provided around the spindle motor 12 so as to be able to move up and down.
A signal transfer element 73 is provided on the upper surface of 31, and an optical head 14 is provided on the lower surface of the signal transfer element 73. As shown in FIG. 35, the signal transfer element 73 is formed narrower than the transparent substrate 81 along one side of the rectangular transparent substrate 81. The signal transfer element 73 is the same as that shown in FIGS.
4, the film structure as shown in FIGS. 25 and 26 can be appropriately selected and used, and it is provided in the radial direction of the magneto-optical disk 11 over a range wider than the width W of the information recording area. As shown in FIG. 34, the reproducing head laser beam 132 is passed through the signal transfer element 73 to the optical head 14.
The first cylindrical body 74 that focuses on the magnetic signal transfer film 83 and the second cylindrical body 76 that focuses the recording / tracking laser beam 133 onto the film surface of the magneto-optical disk 11 are provided. The optical head 14 has guide rails 6 arranged in the radial direction of the magneto-optical disk 11 with the first cylinder 74 and the second cylinder 76 arranged in the track direction.
2a and 62b are slidably attached, and are driven along the longitudinal direction of the signal transfer element by driving the feed screw 63. Incidentally, the magneto-optical disk 11
Alternatively, a magnetic disk may be used.

36 and 37 are views showing the second example, in which the magneto-optical disk 11 is the disk cartridge 1.
The disk cartridge 141 is rotatably housed therein, and a signal transfer element 73 is attached in the longitudinal direction of a shutter 142 that constitutes the disk cartridge 141. As shown in FIG. 37, the disk cartridge 141 is provided with a turntable 52, an optical head 14, and a head window 143 for inserting the magnetic head 13 therein. A shutter 142 is attached to the inner surface of the disk cartridge 141 so as to be opened and closed. ing. On the inner surface side of the shutter 142, as shown in FIG. 36, the signal transfer element 73 (FIG. 1, FIG. 24, FIG.
5, see FIG. 26), and the surfaces of the shutter 142 and the signal transfer element 73 are covered with a transparent protective film 144. As the optical head 14, the same one as that provided in the magneto-optical disk device of the first example is used.

In the disk cartridge 141, when the magneto-optical disk 11 is mounted on a turntable (not shown), the shutter 142 is opened by a shutter opening / closing mechanism (not shown).
Is partially opened, and the signal transfer element 73 and the opening 145 are arranged in a portion facing the head window 143. Then, the first cylindrical body 7 of the optical head 14
4 is set to face the signal transfer element 73, and the second tubular body 76 is set to face the opening 145. Further, the magnetic head 13 is inserted into the disc cartridge 141 from the other head window 143a provided on the opposite side through the magneto-optical disc 11, and the second cylindrical body 76 is provided.
And is set to face. This makes it possible to record, reproduce, and erase information. Also in this example, a magnetic disk can be used instead of the magneto-optical disk 11. Further, instead of the configuration including the recording / erasing magnetic head 13, a recording magnet 302 for giving a recording magnetic field to the magneto-optical disk or the magnetic disk and a magneto-optical disk or the magnetic disk are provided in the disk cartridge 141. Erasing magnet 30 for applying an erasing magnetic field
It is also possible to adopt a configuration in which 1 and 1 are provided.

38 and 39 are views showing the third example, in which the signal transfer element 73 is set in a fixed portion in the disk drive device 151, and the disk drive device 15
1 mounted on the disk transfer member 153
The recording magnet and the erasing magnet 154 are set to 1.

A signal transfer element 73 is fixed to a portion adjacent to the spindle motor 12 in the disk drive device 151, and an optical head 14 having the same structure as that shown in FIG. 34 is provided below the signal transfer element 73. The signal transfer element 73 has a film structure as shown in FIG. 1, FIG. 24, FIG. 25, and FIG. 26 described above, and is arranged in the radial direction of the magneto-optical disk mounted on the spindle motor 12. Optical head 14
Is a signal transfer element 73 according to the rotation of the feed screw 63.
Are transferred in the arrangement direction. In addition, the disk drive device 15
A disk transfer member 153 that reciprocates between the medium insertion port 152 and the setting portion of the spindle motor 12 is provided in the inside of the apparatus 1. On the other hand, by loading the disk cartridge 141, the shutter 142 of the head window 143 is opened, and the head window 143 is opened.
A recording magnet and an erasing magnet 154 are inserted together with the mount 131, and the recording magnet and the erasing magnet 154 are set in the radial direction of the magneto-optical disk.

Immediately after the disc cartridge is inserted, as shown in FIG. 38, the disc transfer member 153 is arranged to face the medium insertion port 152. When the disc cartridge 141 is completely inserted into the disc transfer member 153, the disc transfer member 153 is lowered and the disc 11 housed in the disc cartridge 141 is attached to the spindle motor 12 as shown in FIG. It is mounted on the turntable 52. At this time,
The shutter 142 has already been opened, and the signal transfer element 73 is inserted into the disk cartridge 141 through the head window 143, whereby recording, reproduction and erasing of information becomes possible.

In this embodiment, as shown in FIG. 40, a recording or erasing laser beam emitted from a general recording / reproducing optical head 14 is focused on a magneto-optical recording medium. Information can be recorded or erased, and the reproduction laser spot 86b can be formed on the signal transfer element 7.
By focusing on 3, the recorded information can be reproduced.

In addition, in the present embodiment, the signal transfer element 73 can be configured as follows. That is, as shown in FIG. 41, the reproduction laser spot 86b is focused along the edge portion 73a of the signal transfer element 73,
By monitoring the intensity of the reflected light, it is possible to prevent the reproduction laser spot 86b from falling off the signal transfer element 73. As shown in FIGS. 42 and 43, the signal transfer element 73 is provided with a guide groove 155 for the reproducing laser spot 86b, and the intensity of the reflected light from the signal transferring element 73 is monitored to detect the reproducing laser spot 86b. It is also possible to prevent derailment from the signal transfer element 73. The guide groove 155 may be one as shown in FIG. Further, as shown in FIG. 45, the signal transfer element 73 can be formed to have a narrow width, and the two tracking laser spots 87a and 87b can be focused on the disk surface of the magneto-optical disk from both sides thereof.
Also, as shown in FIG. 46, the narrow signal transfer element 73 is provided with two guide grooves 155, and two tracking laser spots 87a and 87b are focused on the disk surface of the magneto-optical disk from both sides thereof. You can also Further, as shown in FIG. 47, one narrow guide groove 155 is provided in the narrow signal transfer element 73, and two tracking laser spots 87a and 87b are focused on the disk surface of the magneto-optical disk from both sides thereof. You can also do it.

In the embodiment, the first cylinder 74 for irradiating the optical head 14 with the reproducing laser spot 86b and the tracking laser spot 87 are used.
The second cylindrical body 76 for irradiating a and 87b is provided. However, as shown in FIG. 48, by devising the objective lens, the reproduction laser spot 86b and the tracking laser from one objective lens 72 can be obtained. Spots 87a, 87
It is also possible to irradiate b.

Further, in each of the above-mentioned embodiments, the disk drive device has been described as an example, but it can be applied to a drive device for a card-shaped recording medium and a drive device for a tape-shaped recording medium.

Further, in each of the above embodiments, FIG.
As described above, the optical head provided with one semiconductor laser is used, but the gist of the present invention is not limited to this, and an optical head provided with a plurality of semiconductor lasers can also be used. An example thereof is shown in FIG. As shown in this figure, in the optical head 14 of this example, a first semiconductor laser 201 that emits a reproducing laser beam 201a and a reproducing laser beam 201a are divided into two laser beams, and a magneto-optical disk is formed. A beam splitting element 202 for irradiating two laser spots 87a and 87b on adjacent guide grooves 31 of 11 and a laser beam 20 for recording or erasing.
And a second semiconductor laser 203 for emitting 3a. The first semiconductor laser 201 oscillates when the disk drive device is switched to the reproducing mode, and the second semiconductor laser 203 is oscillated when the disk drive device is switched to the recording mode or the erasing mode. Oscillate. Reference numeral 204 in the figure denotes an actuator for tracking control and focus control. The other parts are formed in the same manner as in FIG. 16, so the corresponding parts are designated by the same reference numerals and the description thereof is omitted.

[0058]

As described above, according to the present invention,
Since the reflection film and the enhancement film necessary for improving the reproduction sensitivity are formed on the signal transfer element side of the optical head, these reflection film and the enhancement film are not required on the magneto-optical disk side,
The film structure of the magneto-optical disk can be simplified. Further, since the magneto-optical disk is only required to have characteristics such as good recording sensitivity and capable of holding a large recording magnetic field, it is possible to widen the selection range of the magnetic material as the information recording film.
Therefore, from the above, it is possible to improve the mass productivity of the magneto-optical disk and reduce the manufacturing cost. Further, since the servo control laser beam is emitted from the optical head together with the reproduction laser beam, and the optical head is servo-controlled by using the reflected light signal from the information recording medium, the head guide such as the guide groove is formed. Information can be recorded, reproduced, and erased on a high-density recording information recording medium pre-formatted by the means.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an information reproducing portion of a system according to a first embodiment.

FIG. 2 is a sectional view of an information reproducing portion of the system according to the first embodiment.

FIG. 3 is a perspective view of the system according to the first embodiment.

FIG. 4 is an overall configuration diagram of a system according to a first embodiment.

FIG. 5 is a plan view of an optical head.

FIG. 6 is a cross-sectional view of a main part of a magneto-optical disk.

FIG. 7 is a plan view of a main part of a magneto-optical disk.

FIG. 8 is a main part plan view showing another example of the magneto-optical disk.

FIG. 9 is a main part plan view showing still another example of the magneto-optical disk.

FIG. 10 is a cross-sectional view of essential parts showing another example of the magneto-optical disk.

FIG. 11 is a cross-sectional view of an essential part showing still another example of the magneto-optical disk.

FIG. 12 is a cross-sectional view of an essential part showing still another example of the magneto-optical disk.

FIG. 13 is a cross-sectional view of an essential part showing still another example of the magneto-optical disk.

FIG. 14 is an explanatory diagram showing an arrangement example of signal transfer elements.

FIG. 15 is a plan view showing a configuration example of an objective lens.

FIG. 16 is an explanatory diagram of a signal processing device.

FIG. 17 is an explanatory diagram of a servo control required actuator provided in the optical head.

FIG. 18 is an explanatory diagram showing another arrangement example of the signal transfer elements.

FIG. 19 is an explanatory diagram showing still another arrangement example of the signal transfer elements.

FIG. 20 is an explanatory diagram showing still another arrangement example of the signal transfer elements.

FIG. 21 is a plan view showing another configuration example of the objective lens.

FIG. 22 is a plan view showing still another configuration example of the objective lens.

FIG. 23 is a plan view showing still another configuration example of the objective lens.

FIG. 24 is a cross-sectional view showing another example of the film structure of the signal transfer element.

FIG. 25 is a cross-sectional view showing still another example of the film structure of the signal transfer element.

FIG. 26 is a cross-sectional view showing still another example of the film structure of the signal transfer element.

FIG. 27 is a plan view showing another example of the optical head.

28 is a side view of the optical head of FIG. 27. FIG.

FIG. 29 is a perspective view showing still another example of the optical head.

30 is a side view of the optical head of FIG. 29. FIG.

FIG. 31 is a perspective view of a system according to a second embodiment.

FIG. 32 is an explanatory diagram of an information reproducing portion of the system according to the second example.

FIG. 33 is a side view of essential parts of a system according to a third embodiment.

FIG. 34 is an enlarged side view of a main part of the system according to the third example.

FIG. 35 is a plan view of the system according to the third embodiment.

FIG. 36 is a main-portion cross-sectional view showing another example of the system in the third example.

FIG. 37 is a perspective view of the system of FIG. 36.

FIG. 38 is a side sectional view showing still another example of the system according to the third example.

FIG. 39 is a side sectional view of the system of FIG. 38 in an operating state.

FIG. 40 is a plan view of relevant parts of a system according to a third embodiment.

FIG. 41 is a plan view of a principal portion showing another example of the system according to the third embodiment.

FIG. 42 is a main-portion plan view showing still another example of the system according to the third example;

43 is a cross-sectional view taken along the line AA of FIG. 42.

FIG. 44 is a main-portion plan view showing still another example of the system according to the third example;

FIG. 45 is a main-portion plan view showing still another example of the system according to the third example.

FIG. 46 is a main-portion plan view showing still another example of the system according to the third embodiment.

FIG. 47 is a main-portion plan view showing still another example of the system according to the third example;

FIG. 48 is a main-portion cross-sectional view showing still another example of the system according to the third example.

FIG. 49 is a cross-sectional view of a head device according to a conventional example.

FIG. 50 is an explanatory diagram showing another example of the optical head according to the present invention.

[Explanation of symbols]

11 magneto-optical disk 11a magnetic disk 13 Magnetic head 14 Optical head 31 guide groove 34 Magneto-optical recording film 72 Playback objective lens 73 Signal transfer element 75 Recording objective lens 83 Magnetic signal transfer film

Claims (26)

(57) [Claims] 1. An information recording medium having a magnetic material film, and an information recording medium arranged opposite to the magnetic material film and recorded on the magnetic material film.
A signal transfer element for magnetically transferring information and the signal transfer
An enhancement film and a reflection film provided on the device, and the signal
Irradiating a laser beam for reproduction to the transfer element, magnetic Kerr effect
Alternatively, by utilizing the Faraday effect,
The transferred information signal is read out optically and the information
The recording medium is irradiated with the laser beam for servo control,
Light that generates servo signals for locking and focusing
An information recording / reproducing system including a learning head . 2. The information recording / reproducing system according to claim 1.
At the laser beam emitting port of the optical head,
A signal transfer device including the enhancement film and the reflection film
Information recording and reproducing system, characterized in that a. 3. The information recording / reproducing system according to claim 1.
In the system, the enhancement film and the reflection film are provided.
The signal transfer element is used to record the information outside the optical head.
An information recording / reproducing system characterized by being arranged in a portion facing a medium . 4. The information recording / reproducing system according to claim 1.
Oite the beam, the information recording medium, photothermal information on the substrate - the information recording and reproducing system, wherein the magneto-optical recording film for magnetic recording is a magneto-optical recording medium provided. 5. The information recording / reproducing system according to claim 1.
Oite the beam, the information recording medium, the information recording and reproducing system, characterized in that a magnetic film for magnetically recording information on a substrate at room temperature is a magnetic recording medium provided. 6. Recording / reproducing of information according to claim 4 or 5.
Oite the system, on the surface of the substrate, the signal for tracking control are formed in the form of a guide groove or guide pits and preformat signals required for recording and reproducing information is formed in the form of pre-pits An information recording / reproducing system characterized by being present. 7. Recording / reproducing of information according to claim 4 or 5.
Oite the system, the information on the magnetic film of the recording medium, preformat signals required for recording and reproduction of signals and information for tracking control, recording and reproducing system of information characterized in that it is magnetically recorded. 8. The recording / reproducing of the information according to claim 4 or 5.
Oite the system, the substrate, recording and reproducing system of information characterized in that it is formed with a hard material. 9. Recording / reproduction of information according to claim 4 or 5.
Oite the system, the substrate, recording and reproducing system of information characterized in that it is formed with a flexible material. 10. A recording / reproducing system for the information according to claim 1.
Oite in Temu, the information recording medium, the information recording and reproducing system, characterized in that the disc-shaped, a card-like or tape-like. 11. A recording / reproducing system for information according to claim 4.
Oite in Temu, as the magneto-optical recording film, the saturation magnetization and the coercive force at 60 ° C. or less, sufficiently higher than the saturation magnetization and the coercive force at less 60 ° C. of the magnetic signal transfer film constituting the signal transfer element, An information recording / reproducing system characterized by using a magnetic film having a Curie temperature within a temperature range of 20 ° C to 300 ° C. 12. A recording / reproducing system for the information according to claim 1.
Oite in Temu, the optical head, and one laser light source, a beam splitter for splitting the laser beam emitted from the laser light source into a plurality Article, a signal transfer element, the signal of the laser beam of the plural rows An objective lens that focuses on the transfer element and the information recording surface of the information recording medium, a circuit that detects a reflected light signal from the signal transfer element, a circuit that generates a servo signal from the reflected light signal, and the servo signal And an actuator for driving the optical head in a direction in which the servo error becomes zero according to the above. 13. A recording / reproducing system for the information according to claim 1.
Oite in Temu, the said signal transfer elements are arranged on a part of the laser beam outlet of the optical head, from a part the signal transfer device is not arranged so as to emit a laser beam for tracking control signal detection An information recording / reproducing system characterized by the above. 14. The information recording / reproducing system according to claim 13.
Oite the stem, the signal transfer element, the laser beam is disposed in a central portion of the exit port, and emits a laser beam for servo signal detection of two rows from the transparent part of the periphery of the signal transfer element, one laser any hand of the guide grooves or guide pits for Article 2 adjacent to each beam, the information recording and reproducing system, characterized in that respectively focus the other laser beam to the other guide groove or guide pit . 15. The information recording / reproducing system according to claim 13.
Oite the stem, the signal transfer element, is disposed at a position biased to the upstream side or downstream side of the track direction from the center portion of the laser beam outlet, the arranging portion outside the transparent portion of the signal transfer device 1 A recording / reproducing system for information, characterized in that a laser beam for detecting a servo signal of a strip is emitted and the laser beam is focused on any one of the guide groove or the guide pit. 16. A recording / reproducing system for the information according to claim 1.
Oite in Temu, the irradiation of the reproduction laser beam, recording and reproducing system of said irradiation of the servo control laser beam, characterized in that the so performed simultaneously information. 17. A recording / reproducing system for the information according to claim 1.
Oite in Temu, as the objective lens, the focal length of the portion where the reproducing laser beam is transmitted is shortened, characterized in that the focal length of the portion where the servo control laser beam passes through is used a longer composite lens Information recording / playback system. 18. A recording / reproducing system for information according to claim 1.
Oite in Temu, as the objective lens, the focal depth of the portion reproducing laser beam passes through is small, characterized by using a compound lens focal depth is large portion in which the servo control laser beam passes through Information recording / playback system. 19. A recording / reproducing system for information according to claim 1.
Use Oite in Temu, as the objective lens, the focal length or focal depth of the portion where the reproducing laser beam passes through, the focal length or focal depth is different composite lens portion in which the servo-control laser beam passes through An information recording / reproducing system characterized in that 20. A recording / reproducing system for information according to claim 3.
Oite in Temu, the signal transfer element, over a wider range than the head moving range of at least the information recording medium, the information recording and reproducing system, characterized in that it is secured in a direction perpendicular to the track direction. 21. A recording / reproducing system for information according to claim 1.
Oite in Temu, the signal transfer element, recording and reproducing system of information, characterized in that it is fixed in a cartridge case for accommodating the information recording medium. 22. A recording / reproducing system for the information according to claim 1.
Oite in Temu, the signal transfer element, recording and reproducing system of information, characterized in that fixed to the member housed in the drive device for mounting the information recording medium. 23. A recording / reproducing system for the information according to claim 22.
Oite the stem, when mounting the information recording medium in the drive device, and wherein the member and the signal transfer element fixed thereto is disposed near the magnetic film of the information recording medium Information recording / playback system. 24. A recording / reproducing system for the information according to claim 1.
Oite in Temu, the part of the signal transfer device, the information recording and reproducing system, characterized in that the formation of the guide groove for preventing derailing of the laser beam for the information signal detection. 25. A recording / reproducing system for information according to claim 1.
System, as an information recording medium, an enhanced film and
Characterized by using a magneto-optical recording medium without a reflective film
Recording and reproducing system for information. 26. A recording / reproducing system for the information according to claim 1.
System, an enhanced film is used as the information recording medium.
Information characterized by using a magneto-optical recording medium that does not have
Recording and playback system.