JPH0210568A - Optical or magneto-optical data system - Google Patents

Abstract

PURPOSE: To virtually unnecessitate approaching or separating an optical head to or from a medium by providing with a precise stabilizing means for stabilizing a flexible medium at a required position. CONSTITUTION: Stabilization and predictability are brought from a plate 66 and a coupler 64 provided in a cartridge 12. The primary stability of the medium is brought from the plate 60. On the other hand, the secondary stability of the medium is brought from the coupler 64. The surface of the plate 66 facing a disk 20 is Bernoulli's surface, whereby an air bearing is made between the disk 20 and the plate 66 to function as a bearing. By this way, during reading/writing operation, the flexible optical medium is precisely stabilized, thereby unnecessitating a dynamic convergence system.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is in the field of optical information storage systems.
[Prior art] What is currently being emphasized in the development of information storage systems is the so-called R desk, 8971 size computer,
The ability to store more information in a memory system. Winchester disk driven memory
Desktop-sized memory systems incorporating magnetically recorded hard disk media, such as those used in systems, currently have the ability to store up to 20 megabytes of magnetically recorded information. We are prepared.

A problem with such memory systems is that they necessarily require the hard disk media to be permanently mounted in the computer. Since the hard disk media cannot be easily removed, the user is limited to the portion of the hard disk that is left for information storage at the time of use. Therefore, magnetically recorded hard disk media information storage systems are not considered to be a viable solution for increasing information storage capacity.

The so-called R-F-J disk memory system has flexible disks each having a diameter of either 5.25 inches or 3.50 inches.
It is used as a storage medium that provides a storage medium that can be easily removed. However, the problem with such storage media is that the storage capacity of magnetically recorded information on a single floppy disk currently used in such systems cannot reach the storage capacity of the hard disk. There is no such thing. That is, the magnetically recorded information that a single floppy disk medium can store is only about 1 to 2 megabytes into a system for information storage that can be accessed through a 0° optical armament. Of significant interest is that such systems can store far more data than can be obtained with either magnetically recorded hard disk or floppy disk recording systems. , with a potential capacity to store information on the order of 400 to 800 megabytes. One reason why the storage capacity of optical storage systems has increased so much is because the diameter of the focused beam of light used to read or write information is typically only 1 micrometer (micron). 7 As a result, the density of information stored on the media is much greater than that of typical magnetic recording, and the format of the media for use in such optical systems is , may be in the form of a so-called floppy disk, which is an easily removable medium. Unfortunately, the relatively slow speed of information retrieval compared to magnetic storage systems and current dimensions have limited their use to so-called "desk top" computers, and Major problems such as the limited ability to write/erase and rewrite information multiple times on the media continue to hinder the development and commercial acceptance of such optical systems.

First, consider the current size limitations. The so-called RDesktop J Conbuque is equipped with a large number of modular components, among others.

Contains an information storage system. By adding an information storage system to the casing, a computer can be tailored to a certain extent to meet specific needs. Because such components can be of any size, the American National Standards Institute has adopted specific external reference dimensions for such components, which are generally based on full-hide and half-bite standards. It is said. For such modular components, the half-byte standard appears to be most desirable and there is a need to develop optical information storage systems that comply with the half-hide standard. The half-hide standards for modular components are: 1.625 inches high by 5 inches wide.
75 inches by 8.00 inches deep.The problem with current optical storage systems is that the components required by current designs and techniques easily exceed this dimensional standard when assembled. It is. Only a few of the currently available optical storage systems meet such dimensional standards with the optical head assembly being only one component of the optical storage system. I don't think so.

Next, consider that the information retrieval speed of current optical information systems is relatively fast compared to magnetic storage systems. One of the primary causes of slow access problems in current optical storage systems is the weight of the optical head assembly. As expected, the heavier the device for reading from and writing to the optical disc, the more
Orienting such devices to precise locations on a rotating disk becomes increasingly difficult and therefore slow.

Current optical storage systems include those found in video disc or compact disc (CD) players, which are the extremes of read-only systems, and those called write-once-read-many (WORM) optical storage systems. Contains things.

Currently, the ability to write to and read from optical disks multiple times is limited primarily by the media available for use in such systems. However, it should be understood that the invention is not limited to currently existing media.

In current CO systems, the optical disk rotates about a central axis. The laser beam is projected onto the surface of the optical disc by means of a lens, reflector or beam brick. The laser beam is modulated by information stored on an optical disk, and a photodetector detects the modulated light. The output signal from the photodetector is provided to a sensor for producing an information signal and tracking the signal. The optical head assembly is stored on a disk when the laser-beam source, lens, mirror, projection lens and photodetector are collectively referred to as an optical head assembly. move radially across the rotating disk to access the information.

Because the information being read or written on an optical disk is stored in narrow tracks, coarse and fine radial movement mechanisms are provided.

Until now, it has been considered impossible to combine gross and fine movements in one mechanism.
0 representative cases that were not even considered desirable,
The coarse radial motion mechanism includes either a pivot arm or a radially oriented track that moves the optical head assembly radially across multiple tracks. The directional motion mechanism generally has a radial axis,
Alternatively, it serves to move the projection lens along either axis that is generally perpendicular to the disk. When moved along a radial axis, the projection lens moves between several proximal tracks; when moved along any axis that is generally perpendicular to the disc, the projection lens During operation, the laser beam can be dynamically focused on the surface of the disk. Such fine motor mechanisms are commercially available from Olympus Corporation (T) IOMAS Series, Lake Success, New York, or PentaTux Technology, Inc., Bloomfield, Colorado (VU108-02 Series). can be found in optical head assemblies that are commercially available. An example of such an optical head assembly can also be found in U.S. Pat. No. 4.092.529 to Aihara et al. The height of such fine motor mechanisms also contributes to size limitation issues. In addition, Win L. and Otsusch's paper “WORMJ for mass storage [PC Magazine, Vol. 6, No. 1]
No. 2 (June 23, 1987), pages 135-148], the WORMOR storage system is also discussed.

Typically, fine motor mechanisms move the projection lens by using relatively large and heavy electromagnets, so
The overall weight of the optical head assembly makes movement of the assembly cumbersome and therefore relatively slow. In an attempt to solve the access time problem, efforts have been reported to shrink optical head assemblies. However, since the fine motor mechanism is still the most important component, the weight and dimensions brought about by such a mechanism remain zero. Optical Engineering Magazine, Volume 26, No. 11 (November 1987 issue),
+140-1145 pages] in an effort to determine data and tracking information signals from a single beam of light.
An optical head assembly is disclosed that describes an anamorphic prism, a combination of a convex lens and a roof prism. Such a combination would result in a reduction in the number of optical components, although the size and weight of the III motion mechanism remain.

In current optical systems, information is written to a disk by burning the information into the medium. At present, no medium has been developed that allows such burn-in to be easily erased and rewritten.

The so-called electromagnetic optical information storage system is a mixture of optical information storage system and magnetic information storage system,
The theoretical upper limit of the storage capacity of such systems appears to have the potential to address not only the desire to increase storage capacity, but also the need to erase optical information and write new information. is estimated to be as high as 300 megabytes per square inch of media. However, in reality, 5.25 inch floppy
On disk, approximately 400 to 800 megabytes of storage can be expected.

In this case, the coercive field required to flip the magnetic field is reduced to almost zero, and a single hit can be recorded using well-known magnetic recording techniques.

In the case of magnetic-optical storage, data is recorded and erased on a thin film of magnetic material having the properties described herein. As with magnetic recording, information is stored as a series of hits. In that sequence, the magnetic field of the film at a given point is either north pole up (digital 1) or north pole down (digital O
), a blank disk has all its magnetic poles pointing down to the north pole. The disadvantages of magnetic and optical media are:
The magnetic field required to flip a single magnetic field from north pole down to north pole up, that is, the holding field, varies greatly with temperature. At room temperature, the holding field required to perform the North Pole flip is so high that regular magnets are too weak. In magneto-optical systems, optical techniques are used to heat selected spots of the medium that pass close to relatively large electromagnets to temperatures of approximately 150°C. In this method, a point on the medium can be heated to lower the holding field required to write one bit of information, and the magnet can be person can be recorded exactly. As the laser beam is cut each time, the just-heated point on the medium cools and directs the north pole in the desired direction? To erase the information so recorded, it is only necessary to reverse the process, i.e., heat that point on the medium with a laser beam so that the north pole on the medium Orient the north pole of the magnet in the direction facing down.

Since contact with the medium is undesirable, relatively large electromagnets have been used. Since such magnets are relatively slow to change their pole direction according to the electrical signal provided to them, the direction of the poles on the medium can be determined by modulating the laser while the magnetic field remains relatively constant. , for example, by flashing.

Reading of information so recorded on magneto-optical disks takes place only through optical components. A low power light beam is focused onto the medium; the reflected light is read from either the top or the bottom of the medium. Due to phenomena known as the Kerr magneto-optic effect and the Faraday effect, the light reflected from or passed through the medium will have a slightly different polarity than the light converging onto the medium. The change in polarity will be either clockwise or counterclockwise, depending on the direction of the North Pole at that point. For a diagrammatic interpretation of the magneto-optical action described above, see Obert P5 Freeze's article, “Erasable Optical Disks, II [IEEE Spectrum, February 1988, pp. 41-45]. .

``T: 1. Problem that the invention seeks to solve'' The problem with such magnetic-optical information storage systems is that they do not require enough power to overwrite information without having to pass over the same point on the medium twice. be. To date, the primary methods for overwriting information on magnetic-optical systems are
It was a step-by-step method. That is, it first passes over the media to erase all information within a given track, and then makes another pass over the same point to record the desired information. During magneto-optical recording, the laser flashes at a high gradient while the medium is continuously moved over an electromagnet with a relatively constant magnetic field, so this two-step method allows the overwriting operation to be completed. This was the primary method to ensure that no unnecessary information remained on the disk.

Attempts to solve M during this time involved the use of two optical heads and an electromagnet arranged in an apparent lead/lag fashion, with the leading head and the leading head in the same pass through the medium on which the information was written. included a method to enable the user to perform erasure operations. Another attempt to solve the two-pass problem was the proposal to use parallel light beams and focus them onto adjacent tracks. Another proposal to solve this problem was to keep the laser power constant while modulating the magnetic iI. This latter proposal was based on the paper by Kopoli, Hiromichi et al., “A new type of magneto-optical head with built-in generator for polarized +1 magnetic fields!
Applied Optics, Volume 27, Volume 4 (February 15, 1988 issue)
, pp. 698-702].

A secondary optical storage system that can overwrite previously stored information in just one pass without the size and access time problems encountered with other optical storage systems. The needs still exist.

[Means for Solving ff, d] According to the second aspect of the invention, an optical read/write storage system for reading and writing data to and from flexible optical or magnetic-optical media is provided. an optical read/write head for providing focused light on the flexible medium and receiving reflected light from the flexible medium; and an optical read/write head remote from or connected to the optical head. near the flexible medium, thereby stabilizing the flexible medium in a desired position, thereby effectively eliminating the need to move the optical head towards or away from the medium in order to keep the light focused onto the medium. An optical read/write storage system is provided comprising micro-stabilizing means placed therein.

According to Kanji aspects of the invention, there is provided an optical read/write storage system for reading and writing data to a flexible optical or magnetic-optical medium, the system comprising: an optical read/write head for transmitting light and detecting light collected from the flexible medium; and associated with or connected to the optical head for stabilizing the flexible medium to a desired degree; eliminating the need to move the optical head toward or away from the medium in order to keep the light focused on the medium;
An optical read/write storage system is provided comprising micro stabilization means blinded near the flexible medium.

According to another aspect of the invention, there is provided an information read/write storage system for reading and writing data to and from a flexible optical or magnetic-optical medium, the information read/write storage system comprising: magnetic recording means having a recording head said near said medium for recording information on said medium at a point defined as being the part of said medium being recorded; providing focused light r8 to said medium and accepting reflected light from said medium for reading said information; and continuous convergent light r8 to said medium for heating said points while said magnetic recording means is recording. An optical read/write storage system is provided comprising an optical read/write means for providing a data storage system.

Embodiments of optical information storage systems according to the present invention are capable of either reading from or writing to optical media at speeds that can be compared to magnetic storage systems. can have a low weight optical head assembly, and can be easily manufactured to dimensions according to half-bite standards.

It is an object of the present invention to provide an optical or magneto-optical information storage system that eliminates the need for a dynamic focusing system by stabilizing the flexible optical media at the gate of read/write operations. This can be seen from the embodiment described above. The stabilization is provided at the primary and secondary levels, both involving the suspension of the medium on air bearings created by means of Bernoulli's principle.

[Example] The invention will now be described, by way of example only, with reference to the accompanying drawing P8.

Information storage system 10 constructed according to principles of the invention
is shown in FIG. The cartridge 12 is shown partially inserted into the disk drive housing 14 and the sliding cover 16 has begun to move laterally. Upon completion of such lateral movement, the aperture 18 (shown in FIGS. 2-4) is exposed and the flexible media disk 20 can be manipulated.

The cartridge 12 is attached to the disk 20 in the housing 14.
A central hub 22 is provided for contact by a drive spindle 24 to rotate the disk 21 when fully inserted therein. guiding the cartridge 12 during insertion;
The bottom cover 26 of the housing 14 is shown partially cut away to expose the needle 28 that guides the arm 30 during access of the disk 20. 1st
Although not shown in full detail in the figures, the distal end of arm 30 includes a head assembly 32. A linear actuator motor 34 serves to move the arm 3o within the needle 28 and move the head assembly 32 radially across the surface of the disk 2o. , several types of linear actuator motors are available, but the selected linear actuator motor is suitable for both track finding IJ and track tracking by head assembly 32 . The range of motion of arm 30, which is desirably capable of providing both motor and fine motion, is from a retracted position shown in FIG. 1 to an extended position where the distal end of arm 30 hits stop 36.

Details of the structure of cartridge 12, in particular cartridge 1
2 and the insertion and contact by the various disk drive components described above are fully described in the following patents and patent applications, which are hereby incorporated by reference: U.S. Pat. No. 4769733, No. 4740851, No. 4743989, No. 47408
No. 51, No. 4658318: r Disk drive motor mounting j - Matsu cart tray and others, April 2, 1986
Application on the 1st: 0' Is it possible to bring the disk into contact with the spindle?
1lJl - Joan et al., filed April 21, 1986: UK Patent Application No. 2190232, also incorporated by reference in the patent application Disc Cartridge J Bauk et al., application no. 947612. No. 4,658,313, issued April 1, 1986, entitled ``Magnetic Disk Cartridge J Bauk.'' The above application relates primarily to magnetically recorded information storage systems. for reading and writing data to and from a medium (the above application discloses the use of two floppy disks in a single cartridge); Otherwise, the structure used in those devices is substantially identical to the structure that can be incorporated into a storage system according to the present invention. It is estimated that a single floppy disk could be used instead of dual media.

A commercially available disk drive for magnetic recording of information that can be modified to provide an optical or magneto-optical information storage system according to the present invention.
The a/cartridge is manufactured by IOM of Roy City, Utah, USA.
Beta 2 manufactured and sold by EGA Corporation
There are 0 systems. In order to be able to convert analog signals created by optically recorded information into digital signals as well, in order to convert analog signals created by magnetically recorded information into digital signals. It will be appreciated that such techniques for converting optically produced analog signals into digital signals may require modification of the circuitry and programming utilized in the Beta 20 system. is well known.

This is shown in Figure M2. Considering an optical information storage system, a disk drive motor 40 rotates a disk 20. Such rotation is initiated by an appropriate permission signal coming from processor 42. As disk 20 rotates, processor 42 provides an enable signal to linear motor 34 to cause optical head assembly 32 to move radially across the surface of disk 20. Head assembly 32, in response to another enable signal from processor 42, illuminates a limited area on disk 20 with a beam of light in a manner described below. disk 20
The information stored thereon modulates the light reflected from the surface of disk 20. This reflected light is detected by the head assembly, converted to an electrical signal, and provides the electrical signal to processor 20. Several methods are known for performing this operation, and the invention is not limited to using any particular method; likewise, the invention not limited to using any particular method for memory;
The processor 42 loads the disk 20 and reads the linear
Motor 34, head assembly 32 and disk 2
0 and causes the head assembly 32 to write the desired information onto the surface of the disk 20.

As in the case of this preferred embodiment, the system
In the case of an optical system, the conversion of the reflected light into an electrical signal is performed by a differential detection mechanism. The light that is reflected from or transmitted through the point on a magnetic-optical disk where information is written has a slightly different polarity than the light that is focused on the medium. There is. Whether the polarity change is clockwise or counterclockwise depends on the direction of the north pole at that point. Pass the reflected light through a beam splitter, detect each split beam, and compare the detected beams. By doing so, it can be determined whether the polarity of the reflected light is modulated and whether it indicates that a digital 1 is stored on the disc. This type of detection mechanism is based on the paper by M. Manslibuhl et al., “Signal and Noise during Magnetic-Optical Reading” [Journal of Applied Physics, Vol. 53, No. 6 (19
Since it is described in another magneto-optical device described in [R, June 1982], pages 4485-4493, it will not be described in detail here.

FIG. 3-M9 shows an optical information system. As shown in FIG. 3, cartridge 12 is fully inserted and arm 30 is extended so that optical head assembly 32 is It is moving radially across the surface of disk 20. The optical head assembly 32 is shown to include a laser diode 44 with a lead 46 attached to the lead 46 for operation in any of several ways, not shown, which are well known in the art. It will be appreciated that 46 is electrically connected to the processor 42, and the laser diode 44 serves as a light source for the optical head assembly 32, as used herein. The term refers to both visible and invisible light, or more precisely, electromagnetic radiation. In particular, the term light includes wavelengths ranging from 200 to 200
Includes light in the range down to 0 manometers (nm).

As shown in the third, fourth and sixth figures, the light emitted from the laser diode 44 passes through the aperture plate 4.
Pass 8. The aperture plate 48 limits the diameter of the beam, but serves to scale the beam to the required dimensions, which in this preferred embodiment are:
The light passing through aperture plate 48, equal to the minimum beam diameter allowed in this optical system, is further focused by lens 50 and applied to polarizing beam splitter 52, where it is directed toward disk 20. or reflected in the direction of the disk 20. The light reflected by polarizing beam splitter 52 then passes through quarter wave plate 54 .

The quarter-wave plate 54 serves, as is well known, to change the plane of polarization of the light.After zero reflection, light passing through the quarter-wave plate 54 has its plane of polarization retarded by 90°. Therefore, the beam must pass through the mirror surface housed in the beam splitter 52 (
It is not reflected back to the diode 44.

The light passing through quarter wave plate 54 toward the disk then passes through lens 56, which focuses the light onto the surface of disk 20. Unlike conventional optical storage systems, lens 56 is not mounted for movement relative to arm 30; in this respect, lens 56 is stationary relative to arm 30. disk 20
The light reflected from the beam 5 is then normalized by the lens 56 and passes through the quarter-wave plate 54. As previously explained, the plane of polarization of the light has been retarded by 90°, so the light is It is carried through a splitter 52 and focused onto a detector 60 by a lens 58. Lenses 56 and 58 may be tone indexing lenses.

Although the detector 60 can be of several different types, the detector used here is a model IT338 manufactured and sold by Sony Corporation. Such a detector performs detection, i.e., serves to identify, both data and tracking information; detector 60 then generates an electrical signal that reflects but is indicative of the detected data and tracking information. The electrical signal created is the lead 62.
is sent to the processor 42 via. As a result, detector 6
The signals from o5 not only serve to provide accessed information, but also allow processor 42 to evaluate the tracking information to determine whether the optical head 32 is positioned radially on disk 20, M3.
so that appropriate signals can be provided or supplied to the linear motor 34 to cause it to follow the desired track on the disk 20. FIG. 4 shows that the lens 56 is mounted on the coupler 64, and that the coupler 64 is securely mounted on the arm 30.

Although not shown, it is understood that an opaque cover member may be provided over the optical head assembly 32 to block stray light as well as protect the optical head assembly 32 from the surrounding environment and dust. will be done.

Lens 56 can be statically mounted in arm 30 since there is no need to dynamically focus the light from diode 44. The elimination of the need for dynamic focusing is a result of the disk 20 having some stability and the ability to predict the distance between the disk 20 and the lens 56 during operation. Such stabilization and predictability are due to two sources: the plate 66 provided in the cartridge 12 in this preferred embodiment;
and coupler 64. Plate 60 provides primary stability of the medium, while coupler 64 provides secondary stability of the medium -1'! The surface of the plate 66 facing the disc 20 is a Bernoulli surface, which serves to create and maintain an air bearing between the disc 20 and the plate 66, a structural feature resulting in the creation of an air bearing by the Bernoulli surface. are well known and will not be repeated in this specification, except that in order to avoid the need to dynamically focus the light onto the disk,
The adoption of such phenomena in optical information storage systems is not well known.

Although plate 66 is depicted as part of cartridge 12 in this preferred embodiment, it is within the scope of the present invention to physically attach plate 66 to drive system 10. In such an alternative design, the cartridge 12 would be constructed to allow the plate 66 to be placed near the disk 20 after the cartridge 12 is fully inserted.

It is not well known to employ such phenomena in optical information storage systems.

Although the disk 20 is primarily stabilized by the air bearing created by the plate 66, it will be recalled that the optical head assembly 32 accesses the disk 20 through the aperture 1818, the aperture 18 is also ,
It is also in plate 66. In the part inside the opening 18,
There is no stability of disk 20, so coupler 64 is
Creating and maintaining an air bearing provides local secondary stability to the area surrounding the lens 56. The air bearing creates an air bearing that is in close contact with the coupler 64 and serves to hold the portion of the disk 20 passing under the coupler 64 in a predictable manner, as will be explained shortly. Details of the structure included in the coupler 64 for the purpose of
In order to eliminate the need to dynamically focus the light onto the disk, the surface of the coupler 64 creates an air cushion between the coupler 64 and the disk 200. and is maintaining it. In this preferred embodiment, the distance "A" between coupler 64 and disk 20 is approximately 5-100 microflons ±0. It is micron. There are many alternative coupler shapes and designs that can provide the required media stabilization, and this relationship between coupler 64 and disk 2° is virtually flat around lens 56 (not shown). This is done by providing a surface 7o and proximate surface 70 a series of increasingly steeper surfaces. It will be noted in FIG. 5 that such surfaces may not be easily distinguished and that some exaggeration of the actual shape of the surface is necessary; in this preferred embodiment, the surface Reference numeral 72 denotes an arched surface having an arc radius of approximately 500 mm, surface 74 is also an arched surface having an arc radius of approximately 270 mm, and surface 76 has a radius of approximately 4 mm with respect to surface 7α.
It is a generally flat conical shaped surface formed at a 5° angle.

It will also be noted that the particular arc radii chosen for surfaces 72 and 74 may vary depending on the nature of the medium selected (ζ), such as stiffness, toughness, presence and nature of lubrication, etc. , the arcuate radius of lens 56 (not shown) and the distance that lens 56 projects from surface 70 will also depend on the medium selected.

In this preferred embodiment, lens 56 has an arcuate radius of approximately 50 mm and a protrusion distance of approximately 0 mm from surface 70.
．． 02 mm.

It is important to note that the structure of coupler 64 could be used to stabilize either a rotating flexible disk, such as disk 64, or an optical medium in the form of tape. be. This structure may be coupled to a coupler 64 (either rotating, linearly moving through the coupler 64, or helically operated by a rotating drum, in a manner well known in the magnetic data recording art). It is only necessary to create and maintain an air bearing between the media and the media. In fact, for Bernoulli stabilization of a rotating disk, it may not be necessary to provide plate 66; indeed, in the case of tape media, such stabilization is unnecessary. Therefore, the present invention is applicable to both flexible optical discs and tapes.

Referring to FIG. 7, another embodiment of the optical head assembly shown in FIG. 6 is shown. The light passing through the lens 50 is applied to a prism 80. The prism 80 is a combination anamorphic correction/polarization beam splitter/
It's a prism. In order to reduce the size of the optical head assembly, it has been found that a certain amount of anamorphic correction to the light beam emitted from diode 44 (not shown) is necessary. The shape of prism 80 is selected such that the first optical axis is perpendicular to the last optical axis. Further, an objective lens 82 is used in place of the gradation indexing lens 52 shown in FIG. It has been found that the objective lens provides better wavefront aberration correction than the tone indexing lens 52. To reflect light on the lens, a polarizing beam splitter
A coating 84 is provided. Then this light
It has a plane of polarization slowed by a quarter-wave plate 54.

Referring to FIG. 8, a top view of another embodiment of the optical head assembly shown in FIG. 6 is shown. In a manner similar to the optical head assembly shown in FIG.
An objective lens 82 (not shown in FIG. 8) is provided to focus the light onto it. The presence of prism 84 allows lens 58 and lens 50 to be positioned in sequence, thereby further reducing the height of the optical head assembly. lens 5
Again, a polarizing beam splitter coating is provided to reflect the light to the 8th. The mirror surface 90 acts as a folding mirror and completely reflects the light from the prism 86 and sends it to the lens 82, or it completely reflects the light from the lens 82 and sends it to the prism 86.

Referring to FIG. 9, another embodiment of the optical head assembly shown in FIG. 6 is shown. There may be conditions in which it is desirable to provide a focusing effect, and for that purpose a laser diode 44 is securely mounted on the solenoid-like device 92. However, lens 5
0 and beam splitter 52 are mounted on plunger 94 by strut members 96. Device i92 is designed so that the distance M18 between lens 50 and diode 44 can be selectively changed through the application of an appropriate signal on line 98 by processor 42.

Such a signal would be provided in response to the processor 42 determining the need to focus the light from the signal provided by the detector 60. Methods for making such determinations are currently well known in the context of dynamically focused optical systems.The light emitted from the six-heam sblitter 52 is then reflected by a prism having a mirror surface 98 and The disk 20 is
reaching the surface.

10 to 13 relate to a magnetic-optical storage system according to the present invention. In the following description, components related to the magneto-optical aspects of the invention will be referred to as 100
Indicated by reference numbers above.

As shown in FIG. 10, the cartridge 112 is fully inserted and the arm 130 is
An assembly 132 extends for radial movement across the surface of disk 120. The arm 130 is divided into an upper arm half +30a and a lower arm half +30b, and it will be seen that the disk 120 passes between the two halves.The magnetic-optical head assembly 132 is a head assembly. - Arm halves 130a and 130 to support the optical and magnetic parts of the assembly.
It is shown divided between b. First, the head, which is supported by the upper half of the arm 130a,
Let's consider the optical part of the assembly.In this head assembly, the laser diode 144 has a lead 1.
Although not shown, the lead 146 is shown to be attached to the bus sensor 42 (see FIG. 2) for actuation in any of several well-known ways. It will be understood that the laser diode 144 serves as a light source, and the meaning of the term 0'' light A is the same as previously explained herein.

As shown in FIGS. 10 and 11, the light emitted from laser diode 144 passes through lens 150 and is focused. Therefore, this light passes through a polarizing beam splitter 152 and is then applied to a prism 154 where it is reflected from a mirror surface 155 and directed toward or towards the disk 120 at the lens 1.
50 can be a gradation indexing lens. The light reflected by prism 154 passes through lens 156, which focuses the light onto the surface of disk 120. Unlike conventional magneto-optical storage systems, lens 156 is not mounted in a moving manner relative to arm 130; at this point, lens 156 is stationary relative to arm +30. Light reflected from the surface of disk 120 is focused by lens 156 and prism +54. Pass through V and beam splitter 1
It is reflected by the mirror surface housed in 52. Since the light is reflected from the surface of disk 120, detection will be done by the Kerr effect. The plane of polarization of the beam reflected from the medium (referred to as the "reading beam J") can have 2fl neck directions, depending on the direction of the magnetic moment at the point of reflection on the medium.Reflections in those directions The plane of polarization of each beam is rotated by a few degrees with respect to the plane of polarization of the illumination beam. The reading beam is re-centered by objective lens 156 and reflected by prism 153 back to beam splitter 152. This preferred embodiment In the beam splitter 15
2 is a leaky polarizing beam splitter, which not only reflects the polarization component of the reading beam created by the rotational effect of the medium, but also reflects the larger polarization component of the light in the opposite side of the illumination beam. Certain amounts of components are also reflected. As a result, the portion of the read beam reflected by the beam splitter 152 is the portion where the overall intensity of the read beam incident on the beam splitter 152 is essentially constant, but with a possible polarization direction of 2flff. The difference in rotation between is exaggerated. The read beam then passes through a partial single wave plate 157 to a beam splitter 158. Beam splitter 158 is a polarizing beam splitter that splits the light into two component beams and separates each component beam.
The beams are focused onto detectors 160a and 160b by lenses 159a and 159b, respectively. lens
156, 159a and +59b It can be a gradation indexing lens. The one-wavelength plate 157 in the part is
It serves as a rotator for rotating the polarization plane of the reading beam by about 45 degrees, and is adjusted so that the intensity of the reflected light and the transmitted light at the beam splitter 158 are equal on average.

Detectors 160a and 160b can be of several different types, but the detectors used here are:
The model is IT338, manufactured and sold by Sony Corporation. Such a detector serves to detect or identify both data and tracking information, a detector! 60a and 1608 make an electrical signal that reflects or indicates the detected data and tracking information.0 The signal made is then read 162￥! is sent to the processor 42 through. As previously explained, the signals from each detector are compared in sensor 42 to determine if there is a difference between the two signals.The difference between the two signals is an indication of the dominant polarity of the magnetism. Therefore, the logical state stored at a reflective point on disk 120 is 0. For example, a positive difference indicates that a digital O is stored at that point, and a negative difference indicates that a digital O is stored at that point. Indicates that the

The signals coming from the detectors not only serve to provide the accessed information, but also allow the processor to evaluate tracking information and the magneto-optic end assembly 132 to the required information on the disk 120. Suitable signals can be provided or supplied to the linear motor 134 to move the arm 130 in a manner capable of radially displacing and following the tracks of the linear motor 134. Lens 156 is securely mounted within support disk 164, and support disk 164 is securely mounted within arm half 130a.

The magnetic head 170 is securely fixed to the lower half 130b of the arm. Magnetic head 170 and lens 156
Moving the media in the darkness allows information to be magnetically recorded on the disk 120 at points heated by light focused by the lens 156.

Since there is no need to dynamically focus the light emitted from diode 144, lens 156 and magnetic head 170 can be mounted stationary within arm 130. The need for dynamic focusing of this light is eliminated as a result of the disk 120 being provided with some stability and the distance between the disk 120 and the lens 156 being predictable during operation. It is. Such stability and predictability result from two sources: the plate 66, which is provided within the cartridge 112 in this preferred embodiment, and the magnetic plate 170. Plate 166 provides primary stability of the medium;
Magnetic head 170 provides secondary stability for the media.

The surface of the plate 166 facing the disc 120 is a Bernoulli surface, which serves to create and maintain an air bearing between the disc and the plate 166. The characteristics are well known and will not be repeated in this specification, although the employment of such phenomena in magneto-optical information storage systems to eliminate the need to dynamically focus light onto a disk is well known. isn't it.

In this preferred embodiment, plate 166 is
Although shown as an integral part of cartridge 112, plate 166 can be physically attached to drive unit 110 in alternative configurations. In this alternative design, 1, cartridge 110 is suitably modified to allow plate 166 to be placed near disk 1200. As a result, the operation of the Bernoulli surface of plate 166 in providing primary stability of disk 120 once cartridge 112 is fully inserted into drive arrangement M110 is
Essentially the same as already described.

Although not shown, a translucent cover member can be provided over the magneto-optic head assembly 132 to block stray light and to protect the magneto-optic head assembly 132 from the surrounding environment and dust. It will be understood.

The disk 120 is stabilized by the hollow 2 bearings created by the plate 166, while the magnetic-optical head assembly 132 has an aperture 181F! , through disk 1
There is also an opening 18 in plate 166, which will be recalled to be accessing 20. There is no stability of the disc 120 in the part within the opening 18.
As a result, magnetic head 170 provides local secondary stability in the area surrounding lens 156 by creating and maintaining air bearing. The air bearing is connected to the magnetic head 170 and the disk passing through it.
The magnetic head 17 is used to create an air bearing that serves to hold portions of 120 in a close and predictable relationship with the disk +20, as will be explained.
The details of the structure contained within 0 are described in U.S. Pat. No. 4,414,592 to Rossy et al. It is not well known to employ such phenomena in formal information storage systems.

If you look at Figure 12, you will see that the coupler or magnetic head 1γ0
creates and maintains an air bearing between the magnetic head 170 and the disk +20. In this preferred embodiment, the distance between the head and the disk “A
” is approximately 5-100 microns ± 0.0 microns. There are a number of alternative coupler shapes and designs that can provide the required media stability. One such design, ζ This relationship between magnetic head 170 and disk 120 provides magnetic head 170 with a substantially planar surface 171 surrounding lens 56 (not shown);
This is achieved by providing a series of increasingly steeper surfaces near the surface 171. It will be noted in FIG. 12 that such a surface lFr cannot be easily distinguished and some exaggeration of the arcuate surface is necessary; in this preferred embodiment, surface 172 is an arc-shaped surface, and the arc radius is 500 r
nrn, the surface 174 is also an arcuate surface with an arc radius of 270 mm, and the surface 176 is the surface 171
is a generally flat surface configured at an angle of 45° to the surface. Although not shown in Figure 12, the optical herad
Similar secondary stabilization means can be provided for the assembly. In particular, by creating a similar set of arcuate surfaces for coupler 164 surrounding lens 156,
The surroundings of the lens 156 can be stabilized. Therefore, it is within the scope of the present invention to provide such stability in either or both air head 170 and coupler 164.

It is important to note that the magnetic head 170 and coupler 164 structure can be used to stabilize either a rotating flexible disk, such as disk 120, or a tape-shaped magneto-optic medium. . This structure is used in magnetic data recording technology between a magnetic head or coupler and a medium that is rotating, passing linearly through a magnetic head, or being scanned spirally by a rotating drum. is a well-known structure and is only needed to create and maintain the air bearing. In general, it may not be necessary to provide plate 166 for Bernoulli stability of the rotating disk. In fact, tape media does not require such stability, so the invention can be applied to both magneto-optical disks and tape.

The surface of the disk +20 is stabilized at a relatively fixed distance from the magnetic head 170, so that the magneto-optical surface can be stabilized at a relatively fixed distance from the magnetic head 170 for initial operation of the magnetic-optical storage system.
The light can be made to continuously focus light onto the surface of the disk 120. As a result, information is stored by changing the direction of the magnetic field of the magnetic recording element of magnetic head 170. Because the magnetic field 170 is the size used to magnetically record information on so-called floppy disks, it overcomes the problem of relatively slow switching of the direction of the magnetic field seen in earlier devices. has been removed.

Referring to FIG. 13, an alternative embodiment of a magnetic-optical head assembly is shown. Instead of dividing the arm 130 into upper and lower halves, it can be used for magnetic recording.
It is desirable to place the optical head 170 and the optical head on the same side of the disk 170, since the object will be magnetically recorded in the same position. However, it will be understood that the magnetic element +80 is an electromagnet to which a magnetic field is applied in accordance with the electrical signals provided on the lead 182. The light to be focused on the surface of the disk 1200 is Arms 184a and 1 of element 80
The height of the magnetic head +70 pointing in the direction between 84b would have to be taken into account, i.e.
Since the magnetic-optical head will be slightly further away from the disk +205, this distance M must be taken into account when selecting the lens 156.

In this paper, we consider a magneto-optical information storage system during write and read operations. During a write operation, the information written on the flexible medium is organized by processor 42 for sequential storage on disk 120. From the signals received from detectors 160a and 160b, the magnetic-optical head assembly detects the disk +
If it is estimated that it is located on the desired track on 20,
Processor 42 generates a signal that activates laser diode 144. When the laser diode 44 is activated, the information to be written is transferred to the magnetic head in a well-known manner.
By varying the direction of the +70 magnetic field, it is stored on disk 120. Since the disk +20 is heated at the point where the light from the laser diode 144 is focused, a pole placed within that heated portion of the medium will take the direction of the magnetic field created by the head +70. Such reorientation of the poles on disk 120 will continue until processor 42 has written all of the information to be stored. Of course, while this write operation is taking place, disk 120 is spinning around hub 22 and linear motor 34 is spinning.
The magnetic-optical head assembly 132 also responds to signals from the processor 325 to read the disk 12.
It will be appreciated that moving arm 30 in such a way as to move radially across zero.

During a read operation, light from laser diode 144 is focused onto the surface of disk 120.

The power that is mistaken for the reading light is the disc 120 due to the light.
Although it is not necessary, it is actually desirable that the power be sufficient to minimize heating. Disc 12
The light reflected from the surface of 0 passes through the magneto-optical head in the manner previously described, resulting in a series of electrical signals which are provided to processor 42. Processor 42 compares the difference between the signals from detectors 160a and 160b and uses this result to determine whether a logic 1 or logic 0 is stored on disk 20.

Essentially, if processor 42 determines that there is a difference between the signals from detectors 160a and 160b, there is a logic 1 on the medium; if there is no difference between the two signals;
There is a logic 0 on the medium.

Although the present invention has been described and illustrated with reference to specific embodiments thereof, those skilled in the art will recognize that without departing from the principles of the invention as herein described and defined in the claims, It will be appreciated that modifications and variations may be made.6 For example, in one alternative configuration, not shown, a rotary actuator motor may be used in place of the linear actuator motor 34. Such a device would move across the surface of disk 20 in a manner similar to the movement of a conventional phonograph tonearm. As a result, in such embodiments:
Arm 30 and needle 28 do not have the shape shown in FIG. 1 and are suitably modified to allow accurate positioning and movement of head assembly 32 across the surface of disk 20. It should be.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an optical information storage system according to the present invention. FIG. 2 is a diagram of the storage system. FIG. 3 is a perspective view of the portion of the system shown in FIG. FIG. 4 is a cross-sectional view taken along line 4--4 of FIG. FIG. 5 is an enlarged view of the portion of the coupler shown in FIG. 3. 6 is a diagram of the optical components shown in FIG. 3; FIG. Figure 'M7 is a side view of an alternative embodiment of the optical component shown in Figure 6. FIG. 8 is a top view of another alternative embodiment of the optical component shown in FIG. 6. 9 is a side view of another alternative embodiment of the optical component shown in FIG. 6; FIG. FIG. 10 is a perspective view of a portion of the magneto-optical information system version of the system shown in FIG. M1. FIG. 11 is a cross-sectional view taken along line +1-I+ in FIG. 10. FIG. 12 is an enlarged view of the coupler and magnetic head portion shown in FIG. 10. FIG. 13 is a side view of an alternative embodiment of a magneto-optic system. procedure? mm drawing method) 1. Description of the case Patent Application No. 59836 of 19992, Name of the invention Optical or Magneto-Optical Data System 3, Person making the amendment Relationship to the case Patent applicant address London, United Kingdom, Varnish, W. 1
．． P3GAF, Milbank, Imperial
Chemical house (no address or other information) name
Imperial Chemical Industries, LLC Outside 1 person 4 agents Address: 1-1-15 Nishi-Shinbashi, Minato-ku, Tokyo 105 (No changes to the engraving of the drawings)

Claims (1)

[Claims] 1. An optical write/read storage system for reading and/or writing data to/from a flexible optical or magnetic/optical medium, the system comprising: an optical read/write head for providing light to a medium and for receiving light reflected from the flexible medium; and an optical read/write head for keeping the light focused on the medium. precision stabilization means associated with or connected to said optical head and placed in close proximity to said flexible medium for stabilizing said flexible medium in a desired position so as to substantially eliminate the need for proximity or separation; Configured storage system. 2. An optical write/read storage system for reading and/or writing data to a flexible optical or magnetic-optical medium, the system comprising: , an optical read/write head for detecting light collected from the flexible medium, and requiring the optical head to be moved substantially closer to or further away from the medium to continue focusing the light onto the medium. precision stabilization means associated with or connected to the optical head and placed in close proximity to the flexible medium for stabilizing the flexible medium in a desired position; 3. The storage system according to claim 1 or 2,
further comprising significant stabilizing means placed near said flexible medium to provide a significant stabilizing effect to said flexible medium during reading and writing of data; A storage system comprising an opening for providing access to the flexible media. 4. An optical write/read storage system for reading and/or writing data to a flexible optical or magnetic-optical medium, the system comprising: providing focused light to the flexible medium; and , an optical read/write head for receiving light reflected from the flexible medium; and an optical read/write head near the flexible medium for providing a significant stabilizing effect to the flexible medium during reading and writing of data. significant stabilization means located and provided with an aperture for providing access to said flexible media medium and providing a type of light suitable for reading and writing information to and from said flexible media; a polarizing beam splitter for receiving the light from the light source; and placing the beam splitter on the flexible medium such that the light coming from the light source is reflected onto the flexible medium; a movement means connected to said beam splitter, for changing the polarization of said light when said light passes therethrough;
optical phase retarder means placed near said beam splitter; and for converging said light passing through said retarder means onto said flexible medium, and for collecting reflected light from said flexible medium and directing the collected light to said flexible medium. lens means placed proximate said retarder means for providing said light to said retarder means; and lens means placed proximate said beam splitter for receiving said reflected light and creating an information signal in response thereto. a detector means connected to said beam splitter such that said optical head does not have to be moved substantially closer or further away from said medium in order to keep said light focused on said medium; and precision stabilization means placed nearby for stabilizing the flexible medium in the required position. 5. A device for reading and/or writing optically detectable data to/from a flexible carrier enclosed in a carriage, the carriage having a means for accessing the flexible carrier. and means for receiving and placing in place a carriage with the aperture, the light beam passing through the aperture of the carriage when the carriage is inserted into the receiving means. the light beam to pass through,
an optical system arranged to converge to a predetermined plane lying within the boundaries of the carriage and the deflected portion of the flexible carrier, in effect
brought into stable alignment with said predetermined plane, thereby causing the flexible carrier to rotate while the flexible carrier is rotating.
Bernoulli effect means for locally deflecting the flexible carrier into the portion of the aperture so that the light beam can remain focused onto the flexible carrier without the need for focusing; equipment. 6. The device of claim 5, wherein the Bernoulli effect means comprises a coupler having a surface arranged to mate with the aperture when the carriage is inserted into the receiving means; The surface is a device that follows the path of travel of the light beam through the coupler. 7. The device of claim 5, wherein the Bernoulli effect means comprises a coupler having a surface arranged to align with the aperture when the carriage is inserted into the receiving means; is an instrument located on the opposite side of the flexible carrier from the optical system. 8. The device according to claim 7, wherein the coupler is magnetically
An instrument consisting of magnetic means used to perform optical data reading and/or writing. 9. The apparatus of claim 5, wherein the Bernoulli effect means comprises a first coupler having a surface arranged to mate with the aperture when the carriage is inserted into the receiving means; a second coupler having a surface arranged to be aligned with the aperture when inserted into the aperture, the first coupler and the second coupler being on opposite sides of the predetermined convergence plane of the light beam. equipment that is placed. 10. Apparatus according to claims 5 to 9, in which the Bernoulli plate is associated with receiving means to effect significant stabilization of the rotating carrier, and the surface of the carrier traverses the opening. When the Bernoulli effect means provides precision stabilization of the portion of the carrier. 11. A device for reading and/or writing optically detectable data to or from a flexible carrier tape, comprising optics arranged to focus a light beam on a predetermined plane. a read/write assembly including a system; a means for transporting the tape along a path across the read/write assembly; and a deflected portion of the carrier substantially brought into stable alignment with the predetermined plane; in the vicinity of the read/write assembly so that the light beam can remain focused onto the tape without the need for focusing while the tape is moving past the read/write assembly. for locally deflecting flexible tape.
An apparatus consisting of Bernoulli effect means. 12. Apparatus according to claim 11, wherein the Bernoulli effect means is located in the area of the read/write assembly so that the plane over which the tape passes when the tape traverses the read/write assembly. A device consisting of a coupler with 13. A device according to claims 6 to 10 and claim 11, wherein the (or each) coupler has a demarcation line where the coupler surface extends away from the predetermined plane. 14. The device of claim 12, wherein the bounding surface is comprised of a number of surface portions having different slopes or radii of curvature. 15. An information reading/writing storage system for reading and/or writing data to/from a flexible magnetic/optical medium, the portion of said medium on which information is to be recorded at a certain time. a magnetic recording means placed near said medium for recording information on said medium at a point defined as; and for receiving light reflected from said medium for reading said information; , to heat the point and continue to provide focused light onto the medium while the magnetic recording means is recording;
an information read/write storage system comprising optical read/write means for providing focused light onto said medium during reading and writing.