JPH0322236A - Small-sized magneto-optical disk device - Google Patents

Abstract

PURPOSE:To make a magneto-optical disk device small in size and light in weight and to reduce energy consumption by using a magneto-optical disk cartridge housing a magneto-optical disk, whose recording width is less than 6mm, and contriving arrangement for the fixed part and movable part of an optical recording and reproducing device. CONSTITUTION:In a magneto-optical cartridge 1, the magneto-optical disk, whose recording width is less than 6mm, is housed. On one surface of a base 31, a load inject device 11, electromagnet 12 and electromagnet set device 13 are provided. A fixed unit 15-1 of an optical recording and reproducing device 15 is fixed to the other lower surface of the base 31 in a deep position in the inserting direction of the cartridge 1. A movable part unit 15-2 of the reproduc ing device 15 is fixed to the lower surface of the base 31 in a position corre sponding to the fixed part 15-1. A tracking servo actuator 30, which is provided in this movable part 15-2, executes both feed operation and tracking servo operation to execute search over a recording surface.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a small-sized magneto-optical disk device that performs recording/reproduction using, for example, a 2.5-inch magneto-optical disk cartridge.

(Prior Art) In recent years, magneto-optical disk devices have been used for recording computer data, document files, and the like.

The magneto-optical disk cartridge used in this device is
A magneto-optical disk for recording/reproducing that can be freely erased and rewritten is housed in a resin case for ease of handling and for making it detachable from a recording/reproducing device. These magneto-optical disks come in various sizes, from large 12-inch disks to small 5.25-inch disks and 3.5-inch disks. The type is attracting attention.

FIG. 8 is a block diagram showing an example of a conventional 3.5-inch magneto-optical disk, FIG. 8A is a plan view, and FIG. 8B is a partially enlarged sectional view.

As shown in the figure, the conventional 3.5-inch magneto-optical disk 42 is a disk made of transparent resin such as polycarbonate, and has a disk on one surface of a substrate 42a for recording and reproducing information using the magneto-optic effect. A magneto-optical film (MO film) 42b made of , Fe, Co, Tb, Gd, etc. is formed, and a protective film 42c made of ultraviolet curing resin or the like is further formed thereon, and a metal for driving the disk 42 is formed in the center. Plate hub 44
As described above, this disk 42 is housed in a resin case (not shown) and becomes a 3.5-inch magneto-optical disk cartridge.

The outer diameter of this disk 42 is φ86 mm, and the outer diameter of the recording area 43 where information is recorded/reproduced on this magneto-optical film 42b is φ80 m+s, and the inner diameter is φ48 mm. The recording width, which is the radial width of the area 43, is 16 mm. In this recording area 43, 10.887 recording tracks with a pitch of 1.5 μm are formed spirally or concentrically. Each recording track is alternately formed with a data area where information is recorded/reproduced and a management area where management/information is recorded in advance.

This conventional 3.5-inch magneto-optical disk 42 has a ninth
It is incorporated and used in a conventional 3.5-inch magneto-optical disk device 50 shown in the figure.

FIG. 9 is an explanatory diagram of recording and reproducing operations of an example of a conventional 3.5-inch magneto-optical disk device.

As shown in the figure, the conventional 3.5-inch magneto-optical disk device 50 includes, in addition to the 3.5-inch magneto-optical disk 42, a base 51, an electromagnet 52, an optical recording/reproducing device 55,
It is composed of a feed device 61 and the like.

The aforementioned 3.5-inch magneto-optical disk 42 is driven by a spindle motor (not shown) fixed to the base 51.
This electromagnet 52, which is rotated at a C A V of 3.80 Orpm and is placed on the protective film 42c side with a gap in between, applies a perpendicular bias magnetic field to the magneto-optical film 42b.

Further, information is recorded and reproduced from the substrate 42a side onto the magneto-optical film 42b using the laser beam 27 from the optical recording and reproducing device 55.

This optical recording/reproducing device 55 includes a laser diode 16,
Collimating lens 17, beam splitter 20, prism 21-1, objective lens 22, polarizing beam splitter 2
3, condenser lenses 24-1, 24-2, photodiodes 26-1, 26-2, etc.

The laser light emitted from the laser diode 16 is collimated by the collimating lens 17 and then shaped into a predetermined beam cross-sectional shape by a beam shaping prism (not shown), and then passes through the beam splitter 20. The light then enters the prism 21-1. The laser beam 27 reflected by this prism 21-1 is
The objective lens 22 produces a light spot 28 with a minute diameter.
The light is irradiated onto the surface of the magneto-optical film 42b on the recording track of the recording area 43 of the disk 42.

The light spot 28 irradiated onto the surface of the magneto-optical film 42b has a light intensity suitable for recording when the device 50 is operating in the recording mode, and has a light intensity suitable for recording when the device 50 is operating in the reproducing mode. In this state, the laser diode 16 is controlled by an output control device (not shown) so that it has a light intensity suitable for reproduction.

In this recording mode, the magneto-optical Il on the recording track is
The perpendicular magnetization direction of %42b is reversed only where the light spot 28 hits by the bias magnetic field generated by the electromagnet 52, thereby recording this digital signal.

In the case of the reproduction mode, the direction of rotation of the polarization plane of the laser beam reflected on the surface of the magneto-optical film 42b differs depending on the perpendicular magnetization direction of the magneto-optical film 42b due to the magneto-optic effect. The light is reflected by the beam splitter 20 via the objective lens 22 and the prism 21-1, and is incident on the polarizing beam splitter 23 via a half-wave plate (not shown). The laser beam transmitted through the polarizing beam splitter 23 is condensed by the condensing lens 24-1 and sent to the photodiode 26-1.
The laser beam is converted into an electric signal and output as a detection signal, and the laser beam reflected by the polarization beam splitter 23 is focused by the condenser lens 24-2 and converted into an electric signal by the photodiode 26-2. and output as a detection signal.

At this time, the magnitudes of the two detection signals change in opposite directions due to the movement of the polarization beam splitter 23, depending on the rotation direction of the polarization plane. Regeneration takes place.

Of the optical recording/reproducing device 55, the laser diode 16, the collimating lens 17, the beam splitter 20,
Polarizing beam splitter 23, condensing lens 24-1.24
-2, a fixed unit 55-1 consisting of photodiodes 26-1, 26-2, etc. is fixed to the base 51, and a movable unit 55-2 consisting of the prism 21-1, objective lens 22, etc. is the feed device 61
It is fixed to the movable part 6lb. This feed device 6
The movable part 61b of 1 moves the disk 4 by a linear motor 61a of this device 61 fixed to this base 51.
The recording track is searched by moving the optical spot 28 in the radial direction of 2 and moving the optical spot 28 to a range from the outer diameter to the inner diameter of the recording area 43 of this disk 42, a so-called feeding operation. It is something. Note that this base 51 is configured to be held by the main chassis of the device 50 (not shown) via a vibration isolating mechanism (not shown). Also, a so-called focus servo that automatically tracks the focus of the optical spot 28 on the surface of the magneto-optical film 42b with respect to surface wobbling of the disk 42, etc. is based on the detection signal output, This is done by controlling the vertical position of 22 using a focus servo actuator 59.

Also, the so-called tracking servo, which automatically makes the optical spot 28 follow the recording track with respect to the eccentricity of the disk 42, adjusts the direction of the objective lens 22 based on the detection signal output from the management area. This is done by controlling the radial position of the disk 42 by a tracking servo actuator 60. The movement range of this optical spot 28 in the radial direction of this disk 42 by this tracking servo is normally about ±1 degree, so the positioning of this optical spot 28 in the radial direction of this disk 42 requires precise positioning. This tracking servo and rough positioning are responsible for the feed operation.

(Problems to be Solved by the Invention) In the conventional 3.5-inch magneto-optical disk device 50 having the above structure, a portable personal computer capable of operating on battery power, which is a typical example of personal use, is used. When incorporated into a magneto-optical disk device 50, there was a problem in that the outer dimensions of the magneto-optical disk device 50 were large. or,
The problem was that it was too heavy for portable use. Furthermore, there is a problem that power consumption is large when operating on a battery.

The present invention has been made with attention to the above points, and is a small, lightweight, low power consumption, for example, 2.5-inch magneto-optical disk that takes advantage of the characteristics of magneto-optical disks and solves the above problems. The object of the present invention is to provide a compact magneto-optical disk device that uses a cartridge to perform recording/reproduction.

(Means for Solving the Problems) The small magneto-optical disk device of the present invention has a recording area with a width of 6.
An electromagnet having a load/eject device for loading and unloading a small magneto-optical disk cartridge containing a magneto-optical disk of 1 mm or less in size to a predetermined recording/reproducing position, and a bias magnetic field generator for applying a bias magnetic field to a recording area of the magneto-optical disk. an electromagnet setting device that attaches and detaches the electromagnet to a predetermined recording/reproducing position; a rotation drive device that rotationally drives the magneto-optical disk at a predetermined rotational speed; a light emitting element that emits at least a laser beam; a light-receiving element that obtains a detection signal from the reflected light of the disc cartridge, and a fixing unit disposed at a retracted position of the disk cartridge, and disposed on the optical axis of the light beam from the fixing unit;
It has a movable unit including a tracking servo actuator that moves in the radial direction of the disk and performs both a feed operation to perform a search across the recording area and a tracking servo operation, and the movable unit includes a tracking servo actuator that performs both a feed operation and a tracking servo operation to perform a search over the recording area of the disk. an optical recording/playback device that performs recording/playback;
a base on which the load/eject device, the electromagnet, and the electromagnet setting device are mounted on one surface, and a base on which the rotary drive device, the fixed unit and the movable unit of the optical recording/reproducing device are fixed on the other surface; The optical axis direction of the light flux between the unit and the movable unit is configured to be perpendicular to the direction of the optical axis toward the light receiving element and parallel to the other surface of the base, and The distance between the optical axis of the light beam and the other surface of the base to which the movable unit is fixed is approximately 1/2 or less of the outer diameter of the light emitting element.

(Embodiments) Before describing embodiments of the present invention, the basic principle, outline, etc. of the present invention will be explained.

Basic principle The basic method for recording information is magneto-optical recording and reproducing.A disk-shaped recording medium has a spiral sample servo format track formed by mastering, and a servo system follows this track and controls it. It records/plays/erases digital information while Magneto-optical recording is repeatedly recorded and reproduced many times using the high-speed access suitability of the disk medium.

In order to improve high-speed access, which is directly related to the performance of high-speed access optical discs, efforts have been made to reduce the weight of optical pickups, increase the output of the near motors that drive them, and improve control systems.

In order to reduce the weight of the moving parts, the optical system that was integrated in the conventional big-up is separated and made into a fixed part, and the only moving parts are the driving elements necessary for information reading, focusing, and tracking. The separation optical system method is beginning to be adopted.

The present invention is based on the idea of creating a system that prioritizes miniaturization, has a capacity comparable to that of other peripheral devices, and takes advantage of the inherent characteristics of optical disks, and uses separate actuators for the conventional feed system and tracking system. By dividing the work, we can achieve high speed for large strokes, high speed for small ranges,
The system that covered followability was unified, and tracking and access drive were made to use the same actuator, and control operations were performed serially and in a time-sharing manner. Therefore, one actuator is the basic concept of the present invention, and the range that can be covered by one actuator is the information recording range. With this configuration, the weight is only the element that drives the reading lens in the focusing and tracking directions, and the moving weight including the lens, leaf spring, intermediate members, etc. is several grams, thereby ensuring high-speed access with low power consumption. It is possible to construct a compact, large-capacity, non-contact, highly reliable, and highly stable information storage device.

Servo method: In order to enable ROM/RAM compatibility, which is the most important feature of optical discs, a servo method with wide tolerance between the media and the drive is required, and a sample servo method was adopted.

The sample servo method has many features, but the main ones are as follows.

■ The tracking signal is not affected by the recording signal.

■ It is equivalent to the 3-spot method, which has a proven track record for CDs, and eliminates the drawbacks of the push-pull method with respect to beam offset and disk skew.

■ Focus signal detection is on a mirror surface and is not affected by address signals or groove crossing signals.

■ By using the differential method for signal detection, there is a wide tolerance for C/H deterioration.

■ Servo bits move synchronously and act as a limiter against error propagation.

Due to these basic characteristics, we adopted these technical elements as the basic method of this system.

As mentioned above, magneto-optical disks for notebook computers and laptop computers have an appropriate capacity that takes into account their mobility, and are designed to be battery-operated with the aim of downsizing and power saving. 40M
It was set as B. This is a storage capacity comparable to that of an HDD, which is larger than a large ffiFD, and is sufficient when removability is taken into account.

In addition, as the storage area becomes smaller, the range that must be covered by the read/write pickup and the bias magnetic field electromagnet becomes 6.
The size is as small as mm, making it easy to downsize.

Conventionally, the drive mechanism for access was a two-stage control, but by expanding the movable range of the actuator, a one-stage control configuration is now possible, which, combined with the simplification of the mechanism and the reduction of the movable range, increases speed and saves power. It is possible to 2
In the case of stage control, two types of drive systems and control systems are required, and lens position detection, inertial capture, etc. are unnecessary. This configuration provides a mechanism similar to that of an HDD.

Magneto-optical Recording/Reproducing Principle Magneto-optical recording information is stored as the orientation direction of magnetization of a perpendicularly magnetized film with high coercive force. Forming an alignment direction of NSs corresponding to information in such a minute area is a recording operation, and reading out this alignment direction is a reproduction operation.

The external magnetic field required to orient the magnetization of a thin film of recording material used in magneto-optical recording varies with temperature. Even with a weak magnetic field that would not allow recording at room temperature, when the temperature of the recording medium is raised, He becomes smaller and recording becomes possible. When the semiconductor laser beam is narrowed down to a small diameter light spot (1 μm diameter) by an optical system and irradiated onto the recording film,
The temperature of the recording film in the area of the spot diameter rises above the Curie point of 150-200 degrees. At the same time, if an external magnetic field opposite to the initialization is applied, the magnetization will be directed in that direction. When the laser beam irradiation stops, the temperature of the film decreases while the direction of magnetization remains the same, and as a result,
Information is written in a minute area comparable to the laser spot. This is the process of light intensity modulation type recording.

For reproduction, an interaction between light and magnetism called the magnetic Kerr effect is used, which detects changes in the direction of magnetization formed in a minute area by irradiating a spot. When a magnetized magnetic film is irradiated with light, the polarization state of the reflected light rotates depending on the direction of magnetization. If the plane of polarization is rotated by θk degrees for upward magnetization with respect to the recording medium surface, it is rotated by −θkK for downward magnetization. Therefore, the vibration planes of the light differ by 20k degrees between the two polarization planes. The rotation of the plane of polarization is about 0.3 degrees with ordinary magneto-optical materials. This difference is converted into an intensity change by an optical element, photoelectrically converted by a light receiving element, and detected as an electrical signal. The polarization state detection element is an analyzer, and has the property of transmitting polarized light in a certain direction, but reflecting polarized light perpendicular to this direction. The amount of light transmitted through the analyzer is the square of (s1nθ), where θ is the angle difference between the polarization axis (plane) of the incident light and the detection surface (ldl) of the analyzer, and due to this action, the rotation of the polarization plane causes a change in intensity. is converted to

Basic operation of recording, reproducing and erasing of a magneto-optical disk device The recording operation sequence of a magneto-optical disk drive is related to the performance of the driver.

Unlike HDD media, optical disk media have many defects, so in addition to adding an error correction code, it is necessary to verify the recorded data immediately after recording.

The operation of the drive under such an environment will be explained. It is assumed that the drive uses a permanent magnet rotated by a motor or the like as an erase and write bias magnetic field.

Normally, the bias magnetic field is unnecessary, so it stands by at a predetermined position.

The basic recording steps are ■ Magnet reversal (initialization magnetic field setting) ■ Erase operation ■ Magnet reversal (recording magnetic field setting) ■ Recording operation ■ Verification. Furthermore, when performing replacement processing due to a media defect, a replacement processing operation is added. Assuming that the operation sequence is advanced in units of one track, the above steps are advanced for each rotation of the disk.

The power level of the semiconductor laser is set to 1 mW during reproducing operation, 10 mW during erasing operation, and 8II'd during recording operation.

The operation sequence is not limited to this, and there are various variations depending on the design concept of the controller, such as the buffer memory capacity of the drive.

System Configuration of Magneto-Optical Disk Drive The system configuration of the magneto-optical disk drive is as shown in FIG. 5, which will be described later.

There is a host computer, drives, and media, and there is a standardized interface between each of them. SCS is used as the host interface between the host and the drive.
There is an I, PC/AT interface bus, and data is sent and received in a hardware and logically defined format. The drive has built-in controllers for these interfaces and accepts logical formats from the host.
Convert to Sotowo physical format.

The connection between drives and media is standardized by disk standards and cartridges. Data is recorded on the disk.
RAM type for playback, ROM type for playback only, P, ROM (Part
There are three types: (real ROM) type. Currently, the media used is one that cannot be overwritten, but
If this point is improved in the future, the media will be 3FJ, which is non-overwritable, overwritable, and playback only.
There are types.

Such disks are used in cartridges that facilitate installation into drives and protect them from scratches and dust.

Assume that an OS is started on a host and runs an application program on a disk used in the present invention. A disc is inserted into the drive. OS
According to the data management system and commands, information request commands and logical addresses (information write commands, data, and logical addresses) are sent to the driver through the device driver and host interface. The controller interprets the command, converts the logical address into a physical address corresponding to the disk, and issues the deck with a seek to the read (write) track and a read command (write command and data with an error correction code added). The deck moves the optical system to read the data on the disk and sends it to the controller (when writing, the data is modulated and written).

The controller error corrects the read data and sends it to the host through the host interface.

Through such operations, the program operates, and recording and reproduction on the disc is performed.

When using the above-mentioned magneto-optical disk cartridge for personal use, ■ When the user records information in the unrecorded data area of the disk and plays it back, ■ When the user records information in the unrecorded data area of the disk and plays it back, When a user plays back a disc that has been recorded, various applications can be considered, such as (1) a case where the user records desired information on a disc on which some information has been recorded in this data area and then plays it back.

The outer dimensions of a small magneto-optical disk device that performs recording/reproduction using this magneto-optical disk cartridge for personal use are the outer diameter dimensions of a standard 3.5-inch hard disk device built into the conventional personal computer. (Width dimension 4 inches, depth dimension 5.8 inches,
If the height dimension is 1/2 of 1 inch), two such magneto-optical disk devices can be installed in parallel in the space of this 3.5-inch hard disk device, improving usability. When these two units are installed in parallel, it is also possible to combine this hard disk device with the small magneto-optical disk device of the present invention, and in this case, each of the advantages of the high-speed transfer performance of this hard disk device and the removability of this small magneto-optical disk device can be achieved. It becomes a form of helping each other. For example, the width dimension of this magneto-optical disk device is
The depth dimension of this 3.5 inch hard disk device is 17
2, which is 2.9 inches, and the depth dimension is 4, which is the width dimension.
inches, and the height may be the same size of 1 inch. In order to set the width of this small magneto-optical disk device to the above value, the width of the disk cartridge used must be approximately 2.5 inches.

The compact magneto-optical disk device of the present invention uses a magneto-optical disk cartridge in which a magneto-optical disk having a recording width of 60 mm or less is housed in a case of approximately 2.5 inches square, thereby reducing the outer diameter of the device. The above values (width dimension: 2.9 inches, depth dimension: 4 inches, height dimension: 1 inch) are used to achieve small size, light weight, and low power consumption.

FIG. 2 is a configuration diagram showing an example of a 2.5-inch magneto-optical disk cartridge used in the apparatus of the present invention.
) is a plan view of a 2.5-inch magneto-optical disk, the same figure (B)
1 is a partially enlarged cross-sectional view of FIG. 3A, and FIG. 1C is a perspective view of a 2.5-inch magneto-optical disk cartridge. As shown in the figure, the 2.5-inch magneto-optical disk 2 differs from the conventional 3.5-inch magneto-optical disk 42 in terms of outer diameter, recording width, etc., and therefore has similar parts. The explanation will be omitted.

The 2.5-inch magneto-optical disk cartridge 1 includes, in addition to the disk 2, a case 5, a shutter 6, and the like.

This 2.5-inch magneto-optical disk 2 is formed by laminating a substrate 2a, a magneto-optical film (MO film) 2b1 and a protective film 2C, as in the conventional example, and has a hub 4 fixed at the center. The outer diameter of this disk 2 is φ61mm,
The outer diameter of the recording area 3 of this magneto-optical film 2b is φ57
mm, and the inner diameter is φ45 mm, so the recording width is 6 mvg. In this recording area 3, 4,000 recording tracks of 1.5 μ-pitch are formed in a spiral or concentric pattern, and the nominal recording capacity is 40 megabytes. This nominal recording capacity ffi of 40 megabytes corresponds to a recording capacity of 20 to 40 megabytes suitable for personal use.

When considering peripheral devices for personal use, it is necessary to consider matching with the computer's OS. Currently, MS-DOS is widely used as an OS for personal computers, and its software assets are enormous. MS-
In DOS, data management of peripheral devices is done in units of clusters, and the data management capacity is determined by the F/F that manages the cluster.
Depends on the AT bit size. However, the size differs depending on the version, 4085 in 12 bits in Ver 2.0 and 16 in Ver 3.0.
65525 clusters can be managed with bits. V
When managing data size of 20-40MB with e r 2.0, the cluster size will be 8k and 16k bytes, and even data of 1k byte size will be managed as this size, so there may be a lot of waste. . Ve
r 3.0, it is possible to manage data up to 65 MB with a size of 1 kbyte.

In the case of large-capacity optical discs, data is managed as multiple virtual drives, and there are multiple management data sections, which is also inefficient. Therefore, the data size that is best handled as one drive is 60 MB or less.

From this point of view, it is necessary to decide on the format with a drive equivalent to 40 MB in mind. The possibility of a format that takes into account compatibility with the 3.5-inch format will be considered. 3.5 inch format has an inner diameter of 24 mm
This is a format based on R as the recording density, and its parameters are: number of sectors 22, minimum recording wavelength λ-0.
With a track pitch of 1.5μ and a track pitch of 1.5μ, the recording area width that satisfies the total required data of 43MB is 5.82μ. 5
8 am, outermost diameter 29.5 am, disk outer diameter 63
It becomes lIIφ (2.48 inches) and cannot fit into a 2.5 inch cartridge size. The outer diameter of a disc suitable for 2.5 inch size is 61mmφ, and the outermost recording diameter is 28mm.
．． 5mmR, innermost recording diameter 23+uR, recording wavelength 0.8
μ is less than 1, and the signal quality is no longer satisfied. Therefore, it is difficult to create a format that is compatible with the 3.5-inch format.

This time, I decided on the format described below.

That is, the recording capacity suitable for this personal use is 20 to 4
If the nominal recording capacity is set to 40 megabytes, the total required capacity including the management data area, defect replacement area, etc. will be 43 megabytes. Furthermore, if the user data capacity per sector is 512 bytes as in the conventional example, and the number of sectors per recording track is an optimal value of 21, which is around 22 in the conventional example, the number of recording tracks can be obtained from the following formula. .

Number of recording tracks - 43 megabytes/512 bytes x 21: 4,000 lines... (1) Also, the pitch of this recording track is strictly 1.5μ as in the conventional example, and this track pitch and this number of recording tracks Since the product of the above is the recording width, this recording width can be obtained from the following equation.

Recording width - 4,000Xl. 5 μm -6mm...(
2) Also, the number of sectors is 21, the number of segments per sector is 67, and one segment is a total of 11 bytes, including 2 bytes for the servo area and 9 bytes for the data area, and when 4/11 modulation is applied as in the conventional example. , the recording area inner diameter φ45l
Since the minimum recording wavelength in III1 is equal to the minimum recording pit length representing one bit in the innermost recording track, it can be determined from the following equation.

Minimum recording wavelength - π x 45 questions/21 x 67 x 11 x 11 = 0.82 μm
(3) In the case of this minimum recording wavelength of 0.82μ, the C/N ratio at the recording area inner diameter of φ45 mm can be 45 dB or more even if the birefringence of the substrate IC is considered.

Further, in the case of a recording/reproducing apparatus, the above-mentioned tracking servo uses a servo bit formed in advance in the servo area provided at the beginning of each segment of each recording track of the disk 1 to determine the position in the radial direction of the disk 1. A so-called sample servo method is adopted in which the data area following this servo area is free-run after correction is made, and the number of servo samples, which is the number of servo areas per recording track, is calculated from the following formula. It will be done.

Number of servo samples - 21 x 67 - 1,407... (4
) This number of servo samples, 1.407, is 1,372 for the 5.25-inch type and 1,672 for the 3.5-inch type, and is an intermediate value, so it is a value that poses no problem in practice. be.

The format described above is shown in FIG.

One track consists of 21 sectors, and one sector consists of 67 blocks. The first block is an embossed signal, 1~
The 66th block is a rewriting area.

One block consists of 2 servo bytes and 9 data bytes. The first two blocks of the sector are headers, which include a sector mark, sector number, track number, laser power adjustment area, and rectangle.

The disk 2 has a width dimension of 64 mm and a depth dimension of 68 mm.
It is housed in the case 5 made of resin and having a height of 5IllI. In this case 5, a window portion 5a is formed at the center of the surface of the disc 2 on which the recording area 3 is formed, from a position corresponding to the recording area 3 to a position corresponding to the hub 4. Furthermore, a window (not shown) is formed at a position of the window 5a corresponding to the recording area 3 on the opposite side to the surface on which the window 5a is formed. Both windows are closed by the shutter 6 when the magneto-optical disk cartridge 1 is not in use, and when the disk cartridge 1 is in use, the shutter 4 is moved horizontally as shown by the arrow in the figure. It has a structure that can be opened by sliding it.

In this case 5, recording/reproduction control information necessary when recording/reproducing information in the recording area 3, for example, the magneto-optical film 2b is an overwrite film or a non-overwrite film, and the recording track is a single recording track. A recording/reproduction control information recording section 5b is formed in which information such as density or double density is recorded as the presence or absence of a through hole at a predetermined position in one corner of the case 5.

The 2.5-inch magneto-optical disk cartridge 1 having the above configuration is incorporated and used in a 2.5-inch magneto-optical disk device 10 according to an embodiment of the present invention shown in FIG.

FIG. 1 is a schematic configuration diagram showing an example of a 2.5-inch magneto-optical disk device, which is an embodiment of the small-sized magneto-optical disk device of the present invention, and FIG. 1A is a top sectional perspective view; (B)
is a side sectional view.

2.5-inch magneto-optical disk device 1 according to an embodiment of the present invention
0 includes, in addition to the 2.5-inch magneto-optical disk cartridge 1, a load/eject device 11, an electromagnet 12,
Electromagnet vertical device 13, rotation drive device 14, optical recording/reproducing device 15, base 31, electric circuit board 32, chassis 3
It is made up of 3rd grade.

When this disk cartridge 1 is inserted by a user's hand from a cartridge insertion opening 33b provided in the front panel 33a of this chassis 33, this disk cartridge 1 is in an initial position where the open end is in contact with this cartridge insertion opening 33b. The cartridge case 11a of this load/eject device fall is housed in a cartridge case 11a that is slightly larger than the case 5. As the disk cartridge 1 is inserted, the shutter 6 is laterally slid by a shutter opening/closing device (not shown) due to its suppressing force, thereby opening both windows.

When this disk cartridge 1 is manually inserted to the innermost part of the cartridge case lla, the pressing force of this disk cartridge 1 resists the pressing force of spring llb which presses this cartridge case lla downward. When the locking mechanism (not shown) that holds the case lla at this initial position is released, the cartridge case 11a1 and thus the disc cartridge 1 are lowered, and a positioning device (not shown) provided on the upper surface of the base 31 lowers the cartridge case 11a1 and the disc cartridge 1. , the case 5 is positioned at a predetermined recording/reproducing position.

The hub 4 of the disk cartridge 1 connects the spindle motor of the rotary drive device 14 fixed to the lower surface of the base 31 through a window provided in the cartridge case lla and the window 5a of the case 5. The magneto-optical disk is chucked by the attraction force of a chucking magnet (not shown) built into the drive hub 14c to the drive hub 14c fixed to the drive shaft 14b protruding upward through the hole in the base 31 of 14a. 2 is held in a position where it does not contact the inner wall of the case 5. The hub 4, and thus the magneto-optical disk 2, are driven to rotate at a CAV of 3,600 rpm by the rotational torque of the spindle motor 14a.

The electromagnet 12 supplies magnetic flux to the bias magnetic field generating section 12a located on the disk 2 and to the bias magnetic field generating section 12a located at a position deeper than the cartridge case lla in the input direction of the above-mentioned magneto-optical disk cartridge 1. The coil 12b1 is composed of a yoke 12c connecting the two.

When the cartridge case lla is in the initial position, the bias magnetic field generating section 12a is in a standby position on the cartridge case lla.

As the cartridge case lla is lowered as described above, the bias magnetic field generating section 12a is lowered by the lowering distance of the cartridge case lla or more due to the action of the electromagnetic up-and-down device 13 that utilizes the vertical movement of the cartridge case lla. As a result, through the window provided in this cartridge case lla and the window of the case 5, the cartridge is set at a predetermined recording/reproducing position with a clearance from the top surface of the magneto-optical disk 2 of about 0.6 mm.

Further, the fixed unit 15- of the optical recording/reproducing device 15
1 is fixed to the lower surface of the base 31 at a position deeper than the cartridge case lla in the direction in which the magneto-optical disk cartridge 1 is inserted. The movable unit 15-2 of the optical recording/reproducing device 15 is fixed to the lower surface of the base 31 at a position below the cartridge case 11a and corresponding to the fixed unit 15-1. The objective lens 22 held in the center of the movable part 30b in the center of the tracking servo actuator 30 of this movable part unit 15-2 passes through the window part of this cartridge case lla and the window part 5a of the case 5. It faces the recording area 3 of the magneto-optical disk 2.

Further, the recording/reproducing control information recording section 5b of this case 5 is read by an optical reading device (not shown), and the recording/reproducing system is adjusted based on the recording/reproducing control information.

Then, the optical recording/reproducing device 15 starts reading from the radial center of the recording area 3, which is the mechanically stable position of the tracking servo actuator 30, and based on the read position information, performs the following operations as described below. , information is recorded/reproduced at a desired position in this recording area 3.

Various control circuits, drive circuits, related to recording/playback,
Electric circuits such as a data signal processing circuit and an interface circuit are housed in the electric circuit board 32 disposed at the bottom of the chassis 33.

Here, the configuration and operation of the drive including the electric circuit will be explained.

The drive has a host interface as an interface to be connected to a computer, such as PC/AT,
An interface called SCSI is known.

The host interface is connected to the drive's controller.

The main components of the drive are the signal system (LD drive system,
equivalent, modulation/demodulation system), formatter, servo system, controller system, spindle system, and bias magnet system.

The signal system modulates digital data appropriate to the characteristics of the disc, records it on the disc, and demodulates the signal reproduced from the disc through an equivalent system.

The formatter system receives commands from the controller, transmits them to the microcomputer, transmits address data from the disk, and controls operations related to signals.

The servo system includes a focus servo system and a tracking servo system, which control the spot by following surface runout and eccentricity. Also, a seek operation is performed to a target track by an access command.

The controller system includes a host interface, ECC,
Consists of a buffer manager.

The host interface communicates with the host through the host bus.

The FCC adds an error correction code to recorded data, compares written data and reproduced data during verification, and determines whether alternative processing is necessary.

The buffer manager accesses the buffer RAM,
Transfer and control data at high speed between ECC and host interface.

The bias magnet system shapes the magnetic field during recording and erasing.

When the cartridge is inserted into the drive, the shutter oven opens the shutter of the cartridge and sets it in a predetermined position. The cartridge sensor and ID hole sensor detect the mounting state and type of the disc and inform the mechanical controller.

The control of the mechanical controller starts from this point, and the basic operations of the drive include ■motor start, ■standby, ■read, ■write, ■erase, and ■seek. Among these operations, ■ to ■ are operated by the mechanical controller. ■
~■ are commands from the host that are interpreted by the controller and output, which is then controlled by the mechanical controller.

■ Motor start Based on the sensor status of completion of loading, the mechanical controller issues a command to the spindle servo circuit to start the motor.

When the motor starts rotating and reaches constant speed, the rotation lock status is sent to the microcontroller.

■With the standby motor rotating normally, the focus servo is activated and the reading lens is controlled to follow the surface blur. Next, the tracking servo is activated and the spot is controlled by following the deflection of the track. After that, the control track information written on the disc is read and the initial settings of the drive are performed.

■Read A read command is sent from the host. The controller issues a seek command to the mechanical controller. The mechanical controller activates the servo circuit to access the sector of the target track. Notifying the controller of the end of the seek, the controller activates the formatter and instructs data transfer. The formatter transfers the data to the controller, which performs error correction and transfers the requested data to the host.

■Write operation Before the write operation, the erase operation (■) is required.

Light from host. Commands are sent. A seek command is issued from the controller to the mechanical controller. Mechacon sets the magnet to recording mode. Start the servo circuit and perform seek operation. The mechanical controller performs LD power control several sectors before the target sector. Notifies the controller that the write operation is complete. The controller notifies the formatter that write preparation is complete and transfers the data. The formatter performs write operations to disk. Notify the controller of the completion of the operation.

■Erase operation There is a write command from the host. A seek command is issued from the controller to the mechanical controller. The mechanical controller sets the magnet to erase mode. Activate the servo to access the target track sector.

The mechanical controller performs LD power control several sectors before the target sector. Notify the controller that the erase operation is complete. The controller notifies the formatter of the completion of the erase operation.

The formatter activates the LD drive circuit to complete the erase operation. Notify the controller of the end of the operation.

■Seek In seek, the drive CPU instructs the servo system to perform a seek operation upon receiving a command and target track address from the controller. A servo system seek control unit drives the actuator in the tracking direction, controls speed and position based on access code data and wapple bit data, and confirms the target track based on the address to complete the seek operation.

The above operations proceed according to commands from the host.

Also, after this recording/playback is completed, the front panel 33
The cartridge case lla is pushed upward against the pressing force of the spring llb by the user's pressing force on the eject button 11c of the loading/ejecting device 11 provided at a, and when it reaches the initial position. The disk cartridge 1 is held in this position by the locking mechanism, and the end of the disk cartridge 1 is pushed out from the cartridge retainer 33b by a cartridge pushing mechanism (not shown).

At this time, in conjunction with the operation of the cartridge case lla, the bias magnetic field generating section 12a is returned to the standby position by the action of the electromagnetic up/down device 13 described above. When the user removes the disc cartridge 1, the shutter 6 is closed by the shutter opening/closing device, and the disc cartridge 1 is removed.
is taken out.

Note that the base 31 is held by the chassis 33 via an anti-vibration mechanism (not shown).

FIG. 3 is an explanatory diagram of the recording and reproducing operation of the apparatus of FIG. 1.

As shown in the figure, the recording and reproducing operation of the 2.5-inch magneto-optical disk device according to the embodiment of the present invention is similar to that of 3. of the conventional example described above.
In the case of a 5-inch magneto-optical disk device, the above 2
．． Since this embodiment differs in that a 5-inch magneto-optical disk cartridge 1 is used and the feed device 61 is omitted, the same parts as in the conventional example are given the same reference numerals and their explanations will be omitted.

As mentioned above, the 2.5-inch magneto-optical disk 2 has C.
It is rotated at A M 3 , 600 rpm, and a bias magnetic field is applied by the electromagnet 12 to the magneto-optical film 2b. Moreover, this magneto-optical film 2
The laser beam 27 from the optical recording/reproducing device 15 is used to record and reproduce information on the optical recording/reproducing device 15. Although the feed device 61 for moving the movable unit 15-2 of this optical recording and reproducing device 15 is removed, the recording and reproducing operation by this device 15 is the same as that of the conventional example described above. The explanation will be omitted.

The configuration of the optical recording/reproducing device 15 in FIG. 3 is outlined for the purpose of explaining its recording/reproducing operation.
The actual configuration is shown in Figure 4.

FIG. 4 is a block diagram of the optical recording/reproducing device in the apparatus shown in FIG. 1, with FIG. 4(A) being a side sectional view and FIG. 4(B) being a top sectional view.

As shown in the figure, the fixed unit 15-1 of the optical recording/reproducing device 15 includes a laser diode 16, a collimating lens 17, a beam shaping prism 18, a wavelength plate 1
9-1, beam splitter 20, 1/2 wavelength plate 19-2
, prism 21-2, polarizing beam splitter 23, condensing lens 24-1, cylindrical lens 25-1, photodiode 26-1, condensing lens 24-2, prism 21-3,
It consists of a cylindrical lens 25-2, a photodiode 26-2, etc., and these optical components are connected to the base 31.
It is housed in a resin body 29 fixed to the lower surface of the body. Among these optical components, the laser diode 16 usually has the largest outer diameter, so these optical components are aligned on the optical axis from the laser diode 16, and this The height of the lower surface to which the housing 29 is fixed is higher than the height of the lower surface to which the movable unit 15-2 is fixed.

The laser light emitted from this laser diode 16 is
the collimating lens 17, the beam shaping prism 18,
The beam splitter 2 passes through the 1/2 wavelength plate 19-1.
0 and heads toward the movable unit 15-2.

Further, the reflected light from the movable unit 15-2 passes through the beam splitter 20, is reflected by the prism 21-2 via the 1/2 wavelength slope 1-2, and is reflected by the polarizing beam splitter 23. is incident on the The reflected light transmitted through this polarized beam splitter 23 is reflected by the condensing lens 2.
4-1, the reflected light passes through the cylindrical lens 25-1, enters the photodiode 26-1, and is reflected by the polarizing beam splitter 23, passes through the condensing lens 24-2, and enters the prism 21-1. 3, the light passes through the cylindrical lens 25-2 and enters the photodiode 26-2.

Further, the movable unit 15-2 includes a prism 21-1.
, objective lens 22, focus servo actuator 2
1, a tracking servo actuator 30, etc.

Fixed part 3 of this tracking servo actuator 30
0a is fixed to the lower surface of the base 31, and the movable part 30b held by a spring at the center of the fixed part 30a has the fixed part unit 15 at its center.
This prism 21-1 corresponds to the laser beam from -1.
is fixed. Further, above the movable portion 30b of the tracking servo actuator 30, a fixed portion 29a of the two focus servo actuators is fixed, and the movable portion 29b held by a spring at the center of the fixed portion 29a has a The objective lens 22 is fixed at the center of the prism 21-1 in correspondence with the prism 21-1. This objective lens 22 protrudes upward through the hole in the base 31, and faces the recording area 3 of the magneto-optical disk 2 during the above-mentioned recording/reproduction.

Further, the fixed part unit 1 is attached to the fixed part 30a and the movable part 30b of the tracking servo actuator 30.
A blind portion 30c is formed for the light flux between the prism 5-1 and the prism 21-1 so as not to obstruct the light flux.

Moreover, the moving direction of this movable part 30b substantially coincides with the optical axis direction of this light beam, and regardless of the movement of this movable part 30b, the movement direction of this prism 21-1 is on the optical axis in the upward direction perpendicular to the forward axis. The centers of the objective lenses 22 are arranged to substantially coincide with each other.

In the optical recording and reproducing apparatus 15 having the above configuration, as described above, since the recording width of the magneto-optical disk 2 is as narrow as 6 mm, the optical spot 28 is It becomes possible to search the recording tracks in the recording area 3. That is, the prism 21-1 is caused by electromagnetic force caused by magnets and coils (not shown) disposed in the fixed part 30a and the movable part 30b of the tracking servo actuator 30, respectively.
By moving the objective lens 22 in the radial direction of the disk 2 and controlling the position in the radial direction, this feeding operation is performed together with the above-mentioned tracking servo operation. In this case, even if the magnet and coil for this tracking servo operation of this tracking servo actuator 30 are also used for this feeding operation to expand its movement range, due to mechanical and optical limitations, this disk 2 Since the limit value of the movement range in the radial direction is ±3 degrees, this movement range corresponds to the recording width of this disk 2.

Further, in the above-mentioned arrangement of the optical recording/reproducing device 15 in the device 10, the above-mentioned differential The direction of the optical axis toward the two photodiodes 26-1 and 26-2 for signal detection is changed, and the direction of the optical axis toward the two photodiodes 26-1 and 26-2 is changed.
6-2, this fixed part unit }15 including the laser diode 16 within the span in the optical axis direction between both units.
Since the arrangement of each of the optical components constituting the device 1 is approximately included, the depth dimension beyond the cartridge case lla in the insertion direction of the disk cartridge 1 described above is small, and the depth dimension of this device 10 is set to the target value. (4 inches). Also, this fixed part unit 1
The width dimension between this laser diode 16 and photodiode 26-1 of 5-1 is the same as that of this disk cartridge 1.
Therefore, the width of the device 10 can be set to the target value (2.9 inches). Further, the distance between the optical axis of the light beam between the fixed unit 15-1 and the movable unit 15-2 and the lower surface of the base 31 to which the movable unit 15-2 is fixed is the distance between the laser diode 16 The height of the device 10 can be set to the target value (1 inch).

In the 2.5-inch magneto-optical disk device 10 of one embodiment of the present invention having the above configuration, the disk cartridge 1
Since the device 10 is small, the device 10 can be made smaller and lighter.

Further, the disk cartridge 1 itself is small and lightweight, making it convenient to handle, and suitable for personal use, such as fitting into a normal-sized envelope.

Furthermore, since the outer diameter of the magneto-optical disk 2 is small, the spindle motor 14a of the rotational drive device 14 can be small.
Light weight and low power consumption.

Furthermore, since the linear velocity of the recording track of this disk 2 is slow, the power consumption of the laser diode 16 can be reduced.

Furthermore, since the recording width of the disk 2 is narrow, the electromagnet 12 can be made smaller, lighter, and consume less power.

Furthermore, due to the narrow recording width, the feed device 6
1 is removed, the device 10 can be made smaller, lighter, and consume less power.

Furthermore, since the disk cartridge 1 is small, the operation of the load/eject device 11, electromagnetic up/down device 13, etc. is performed manually, resulting in smaller size, lighter weight, and lower power consumption than electric ones. can be measured.

Furthermore, the above-described structure of the optical recording/reproducing device 15 allows the device 10 to be miniaturized as described above.

In addition, in the fixed unit 15l of this device 15, the two photodiodes 26-1 and 26-2 face the same direction, so the photodiode 26-
1 and 26-2.

In the device 10 according to the embodiment of the present invention, an example has been described in which the insertion direction of the disk cartridge 1 is the depth direction of the device 10, but the insertion direction can be changed to the width direction of the device 10. Of course.

Further, although the electromagnet setting device for attaching and detaching the electromagnet 12 to and from the predetermined recording/reproducing position has been described as an example of the electromagnet up/down device 13 that performs vertical movement, it can also be configured to perform rotational movement.

Moreover, although the load/eject device 11 has been described with reference to an example in which the disk cartridge 1 is lowered, it can also be configured such that the base 31 is raised.

(Effects of the Invention) The compact magneto-optical disk device of the present invention having the above configuration can be made smaller, lighter, and consume less power, so it is easier to use when incorporated into a portable personal computer, etc. , suitable for personal use.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an example of a 2.5-inch magneto-optical disk device, which is an embodiment of the small-sized magneto-optical disk device of the present invention, and FIG. 2 is a 2.5-inch magneto-optical disk device used in the device shown in FIG. FIG. 3 is a diagram illustrating the recording and reproducing operation of the device shown in FIG. 1, FIG. 4 is a diagram showing the configuration of the optical recording and reproducing device in the device shown in FIG. A conceptual diagram of the small-sized magneto-optical disk device of the present invention, FIG.
7 is a block diagram of the device shown in FIG. 1, FIG. 8 is a configuration diagram showing an example of a conventional 3.5-inch magneto-optical disk, and FIG. 9 is a block diagram of the conventional 3.5-inch magneto-optical disk.
．． FIG. 2 is an explanatory diagram of recording and reproducing operations of an example of a 5-inch magneto-optical disk device. 1...2.5 inch magneto-optical disk cartridge, 2
...2.5 inch magneto-optical disk, 3...recording area, 4...hub, 5...case, 6...shutter,
10...2.5 inch magneto-optical disk device, 11...
- Load/eject device, 11a... Cartridge case, 12... Electromagnet, 12a... Bias magnetic field generation section, 12b... Coil, 13... Electromagnet up/down device (electromagnet setting device), 1
4... Rotation drive device, 14a... Spindle motor, 14c... Drive hub, 15... Optical recording/reproducing device, 15-1... Fixed part unit, 15-2... Movable part unit , 16...Laser diode, 22...Objective lens, 26-1.26-2...Photodiode, 28...
・Light spot, 2... Focus servo actuator, 30...
- Tracking servo actuator, 31...Base, 32...Electric circuit board, 33...Chassis.

Claims (1)

[Claims] A load/eject device for loading and unloading a small magneto-optical disk cartridge containing a magneto-optical disk with a recording area width of 6 mm or less at a predetermined recording/reproducing position, and a bias magnetic field for applying a bias magnetic field to the recording area of the magneto-optical disk. an electromagnet having a generator, an electromagnet setting device for attaching and detaching the electromagnet to a predetermined recording/reproducing position, and a rotational drive device for rotationally driving the magneto-optical disk at a predetermined rotational speed;
A fixing unit, which includes at least a light emitting element that emits a laser beam and a light receiving element that obtains a detection signal from the light reflected from the magneto-optical disk, is disposed at a retracted position of the disk cartridge; It has a movable unit including a tracking servo actuator which is disposed on the optical axis of the light beam and moves in the radial direction of the disk to perform both a feed operation for searching over the recording area and a tracking servo operation. An optical recording and reproducing device that records/reproduces information in a recording area of a disk, the load/eject device, the electromagnet, and the electromagnet setting device are mounted on one side, and the rotary drive device and the fixed part of the optical recording and reproducing device are mounted on one side. a base having a unit and a movable unit fixed to the other surface thereof, and the light receiving element is directed to the light receiving element in a direction perpendicular to the optical axis direction of the light beam between the fixed unit and the movable unit and parallel to the other surface of the base. The direction of the optical axis is changed, and the distance between the optical axis of the light beam between the two units and the other surface of the base to which the movable unit is fixed is determined by the approximate outer diameter of the light emitting element. A compact magneto-optical disk device characterized in that the size is reduced to 1/2 or less.