JP2006079762A - Optical disc and optical disc cartridge - Google Patents

Abstract

An optical disc cartridge having a large recording capacity and excellent durability and a flexible optical disc suitable for the optical disc cartridge are provided.
A convex portion 6 is formed on one surface of a center hub 5 attached to an optical disc 1 and a concave portion 7 in which the convex portion 6 can be fitted is formed on the other surface of the center hub 5. The convex portions 6 of one optical disc 1 stacked adjacent to each other are fitted with the concave portions 7 of the other optical disc 1, and a plurality of optical discs 1 are stacked concentrically. The convex portion 6 of the center hub 5 provided in the lowermost optical disc 1 is fitted into the concave portion 13 a of the disc support 13 formed on the inner surface of the cartridge case 12.
[Selection] Figure 1

Description

  The present invention relates to an optical disc and an optical disc cartridge, and more particularly to a configuration of a center hub in an optical disc provided with a flexible disc substrate and a center hub and a plurality of optical discs of this type concentrically. .

  In recent years, there have been proposed an optical disc provided with a flexible disc substrate and an optical disc cartridge in which a plurality of optical discs of this type are stored in one cartridge case in a state of being stacked in the plane direction (for example, (See Patent Document 1).

As described above, an optical disc cartridge in which a plurality of optical discs having a flexible disc substrate are accommodated in one cartridge case has a recording capacity per unit volume of an optical disc having a conventional hard disc substrate. Since the number of optical disk cartridges can be increased significantly compared to an optical disk cartridge that accommodates only one sheet, it is possible to increase the capacity of the terabyte class in a random access type information recording medium.
JP 2004-134019 A

  By the way, since the optical disk cartridge described in Patent Document 1 has a plurality of optical disks brought into contact with each other on the disk surface and stacked in the surface direction, while repeatedly carrying out the optical disk from the cartridge case and loading the optical disk into the cartridge case, In addition, the disc surface is easily damaged, and the optical discs stacked on each other during storage tend to stick to each other, and it is difficult to carry out the optical disc from the cartridge case.

  If each optical disk stored in the cartridge case is placed on the tray one by one or stored in the envelope one by one, such inconvenience can be avoided, but on the other hand, it can be stored in the cartridge case. Since the number of optical discs is greatly reduced, it cannot be applied to an optical disc cartridge having a large recording capacity.

  As another means, a center hub having a total thickness larger than that of the disk substrate is provided at the center of the optical disk so that the center hubs are brought into contact with each other, as used in certain types of optical disks and magnetic disks. Although it is possible to suppress a decrease in the number of optical disks that can be stored in the cartridge case and to avoid the inconvenience described above, if the center hubs are brought into contact with each other, radial slip is likely to occur between the optical disks. When stored in the cartridge case, the outer periphery of the optical disk easily collides with the inner wall of the cartridge case, resulting in a new inconvenience that the disk substrate is deformed.

  The present invention has been made to solve such deficiencies in the prior art, and an object of the present invention is to provide an optical disc cartridge having a large recording capacity and excellent durability, and a flexibility suitable for the optical disc cartridge. Is to provide an optical disc.

  In order to solve the above problems, the present invention relates to an optical disc, which has a flexible disc substrate and a center hub having a total thickness larger than that of the disc substrate provided at the center of the disc substrate, A convex portion is formed on one surface of the center hub, and a concave portion for fitting the convex portion is formed on the other surface of the center hub.

  In order to solve the above-described problems, the present invention relates to an optical disc cartridge, in which a plurality of optical discs each having a flexible disc substrate are stored in a single cartridge case in a stacked state in the surface direction. In the optical disc cartridge, as the optical disc, a center hub having a total thickness larger than that of the disc substrate is provided at the center of the flexible disc substrate, and a convex portion is formed on one surface of the center hub. A disk support having a concave portion for fitting the convex portion at a predetermined position on the inner surface as the cartridge case while using a concave portion for fitting the convex portion on the other surface. The projection of the center hub provided on one optical disk stacked adjacent to each other is used for the other. A plurality of optical disks stacked concentrically with the center hubs in contact with each other by being fitted in a recess of a center hub provided on the disk is stored in the cartridge, and formed on the center hub of the lowermost optical disk. The convex portion is fitted into the concave portion of the disk support.

  As described above, when a convex portion is formed on one side of the center hub provided in the optical disc and a concave portion for fitting the convex portion is formed on the other side, when a plurality of optical discs are stacked, they are adjacent to each other. Thus, the convex portion of the center hub provided in one of the optical discs stacked is fitted into the concave portion of the center hub provided in the other optical disc, so that slippage between the optical discs is prevented. In addition, when a plurality of optical discs are stacked concentrically with the center hubs in contact with each other, contact between the disc surfaces can be avoided, so that the disc surface is prevented from being damaged or stuck. Further, a disk support body having a recess for fitting the protrusion formed on the center hub on the inner surface of the cartridge case is formed, and the protrusion formed on the center hub of the lowermost stacked optical disk is supported by the disk. When fitted in the concave portion of the body, sliding between the cartridge case and the optical disk can be prevented, so that collision between the inner surface of the cartridge case and the optical disk is prevented.

  The optical disc of the present invention includes a center hub, and a convex portion is formed on one side of the center hub and a concave portion for fitting the convex portion is formed on the other side. Therefore, when stacking a plurality of optical discs By fitting the convex portion of the center hub provided on one optical disc into the concave portion of the center hub provided on the other optical disc, it is possible to prevent radial slippage between the optical discs. In addition, since the center hubs are brought into contact with each other and a plurality of optical discs are stacked concentrically, direct contact between the disc surfaces can be avoided, so that the disc surface can be prevented from being damaged or fixed.

  Since the optical disk cartridge of the present invention stores a plurality of optical disks stacked concentrically via a center hub, the plurality of optical disks stored in the cartridge case are placed on a tray one by one, The number of optical disks that can be stored in the cartridge case can be increased and the recording capacity can be increased compared with the case where the sheets are stored in the envelope one by one. In addition, an optical disk having a convex portion formed on one side of the center hub and a concave portion for fitting the convex portion on the other side is used, and the convex portion formed on the center hub is fitted on the inner surface. Since the cartridge case in which the disc support having the concave portion is formed is used, the convex portion of the center hub provided in one of the optical discs is fitted into the concave portion of the center hub provided in the other optical disc. And the convex part formed on the center hub of the bottommost optical disk stacked is fitted into the concave part of the disk support to prevent slipping between each optical disk and slipping between the cartridge case and the optical disk. It is possible to prevent deformation and damage of the disk substrate due to the collision between the inner surface of the cartridge case and the optical disk. That. In addition, since a plurality of optical disks can be stacked concentrically by bringing the center hubs into contact with each other, direct contact with the disk surface can be prevented, and damage or sticking of the disk surface can be prevented.

  First, an embodiment of an optical disc according to the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view of an optical disc according to an embodiment, FIG. 2 is a top view of a center hub attached to the optical disc according to the embodiment, and FIG. 3 is a bottom view of the center hub attached to the optical disc according to the embodiment. 4 is a cross-sectional view of a main part showing a stacked state of a plurality of optical discs, and FIG. 5 is an explanatory view showing another example of a convex part and a concave part formed on the center hub.

  As shown in FIG. 1, the optical disc 1 of this example includes a flexible disc substrate 2 having a center hole 2 a, recording films 3 and 4 formed on both front and back surfaces of the disc substrate 2, and the center of the disc substrate 2. It is comprised from the metal center hub 5 attached in the hole 2a.

  The disk substrate 2 is formed by forming a required preformat pattern (not shown) on both the front and back surfaces of a sheet-like body formed in a required shape and size. As the sheet-like body, a plastic sheet such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC) or polyimide, a metal sheet, a low-melting glass plate, or the like can be used.

  The recording films 3 and 4 are formed using any recording material that matches the target optical disc, such as a magneto-optical recording material or a phase change recording material. In FIG. 1, the recording films 3 and 4 are shown as one layer. However, the recording films 3 and 4 may be formed of a laminate of a plurality of films, and the laminate may include a protective layer and a lubricating layer.

  As shown in FIG. 1, the center hub 5 has a total thickness larger than that of the disk substrate 2 and is formed in a coin shape having a center hole 5a for inserting a spindle at the center portion. The front and back surfaces are arranged so as to protrude from the front surface side and the back surface side of the disk substrate 2. The disk substrate 2 and the center hub 5 are integrated by bonding or the like.

  As shown in FIGS. 1 to 3, the center hub 5 of the present example has a conical convex portion 6 in the entire lower portion, and a conical concave portion 7 for fitting the convex portion 6 is formed on the upper portion. Has been. The taper surface 6a formed on the outer periphery of the convex portion 6 and the taper surface 7a formed on the outer periphery of the concave portion 7 have a taper of an appropriate size capable of stably holding a plurality of the optical disks 1 superimposed on each other. It is formed.

  In the optical disc 1 of this example, since the conical convex portion 6 and the concave portion 7 having a shape corresponding to the conical convex portion 6 are formed on the center hub 5, the convex portion 6 is fitted into the concave portion 7 so that a plurality of optical discs 1 are mounted. When stacked in the surface direction, the optical disks 1 are stacked concentrically via the center hub 5 as shown in FIG. Therefore, direct contact of the disk surface is prevented, damage and adhesion of the disk surface are prevented, and slippage is unlikely to occur between the two optical disks 1 stacked adjacent to each other. Can be stably held in a stacked state.

  In addition, the shape of the convex part 6 and the recessed part 7 formed in the center hub 5 is not limited to what was illustrated in FIG. 1 thru | or FIG. 3, It can form arbitrarily. For example, as shown in FIG. 5 (a), a ring-shaped ridge is formed concentrically with the center hole 5a on one side of the center hub 5 as a convex portion 6, and this is formed as a concave portion 7 on the other side of the center hub 5. It is also possible to form a ring-shaped concave groove that can be fitted with the center hole 5a concentrically. In addition, as shown in FIG. 5B, a cross-shaped protrusion is formed around the center hole 5a as a convex portion 6 on one side of the center hub 5, and as a concave portion 7 on the other side of the center hub 5. It is also possible to form a cross-shaped concave groove that can be fitted around the center hole 5a. Further, as shown in FIG. 5 (c), a wide ridge having side portions parallel to each other as a convex portion 6 is formed on one surface of the center hub 5 in the diameter direction passing through the center hole 5a, and the center hub. It is also possible to form a wide concave groove that can be fitted as a concave portion 7 on the other surface of 5 in the diameter direction passing through the center hole 5a.

  In the above embodiment, the center hub 5 is made of metal. However, the gist of the present invention is not limited to this, and the center hub 5 can be formed of a resin material. In the case where the center hub 5 is formed of a resin material, the disk substrate 2 and the center hub 5 can be integrally formed by using an appropriate means such as two-color molding, or the same kind or different kinds of resin materials. The disc substrate 2 and the center hub 5 formed separately can be integrated afterwards.

  Next, an embodiment of an optical disk cartridge according to the present invention will be described with reference to FIGS. 6 is a cross-sectional view of an optical disc cartridge according to the embodiment, FIG. 7 is a perspective view of the optical disc cartridge according to the embodiment, and FIG. 8 is a drive device that mounts the optical disc taken out from the optical disc cartridge and records and reproduces information. FIG.

  As shown in FIGS. 6 and 7, the optical disc cartridge 11 of this example is configured by storing a plurality of optical discs 1 stacked in the surface direction in a box-shaped cartridge case 12. A disk insertion opening 12a is opened on one side of the cartridge case 12, and the optical disk 1 is unloaded from the cartridge case 12 and the optical disk 1 is loaded into the cartridge case 12 through the disk insertion opening 12a. The disk insertion opening 12a may be provided with a dustproof shutter or an opening / closing door. On the upper surface of the bottom plate of the cartridge case 12, a disk support 13 having a conical recess 13a for fitting a conical protrusion 6 formed in the lower portion of the center hub 5 is formed. A plurality of optical disks 1 superposed in the surface direction via the center hub 5 are fitted into the recess 13a by fitting the convex part 6 of the center hub 5 provided in the lowermost optical disk 1 into the cartridge case 12. Is kept stable.

  As described above, the optical disc cartridge 11 of the present example includes the center hub 5 having the convex portion 6 and the concave portion 7 that can be fitted to each of the plurality of optical discs 1 housed in the cartridge case 12, and the cartridge case. Since the disc support 13 having the conical concave portion 13a for fitting the convex portion 6 of the center hub 5 provided in the lowermost optical disc 1 is formed on the upper surface of the bottom plate 12, the surface through the center hub 5 is formed. The plurality of optical discs 1 stacked in the direction can be stably held, and even when the cartridge case 12 is vibrated when being carried or the cartridge case is accidentally dropped from a high place, the disc substrate 1 and the cartridge Collision with the case 12 can be prevented, and damage to the optical disk can be prevented.

  As shown in FIG. 6, the optical disk 1 is unloaded from the optical disk cartridge 11 after the disk separating means 14 is inserted between the optical disk 1A to be unloaded and the upper optical disk 1B stacked on the optical disk 1A. Then, this is raised to release the fitting between the concave portion 7 of the optical disc 1A and the convex portion 6 of the optical disc 1B. Simultaneously with this operation or after this operation, the disc transport means 15 is inserted between the optical disc 1A to be carried out and the lower optical disc 1C on which the optical disc 1A is stacked, and this is raised to project the convexity of the optical disc 1A. The fitting between the portion 6 and the concave portion 7 of the optical disc 1C is released. Thereafter, the disk transport means 15 is moved in the horizontal direction, and the desired optical disk 1A is unloaded from the disk insertion port 12a. Loading of the optical disk 1 into the optical disk cartridge 11 is performed in the reverse procedure.

  As shown in FIG. 8, the optical disc 1 carried out from the optical disc cartridge 11 is mounted on a drive device 21 where information is recorded, reproduced, erased, and the like. The optical disk 1 is mounted in the drive device 21 by inserting the spindle 23 of the rotary motor 22 into the center hole 5a provided in the center hub 5, and information recording, reproduction, erasure, etc. are performed on the optical disk 1. This is done by positioning the head devices 24, 25 on the films 3, 4 respectively.

  Hereinafter, more specific examples of the optical disc 1 according to the present invention will be described.

  A PET sheet having a thickness of 100 μm cut into a 95 mm square was sandwiched by a processing jig, and the outer periphery and the inner periphery were cut out to produce a disk-shaped PET sheet having an outer diameter of 95 mm and an inner diameter of 15 mm.

  At the same time, the first stamper of the land / groove recording system having spiral lands and grooves having a land width of 0.18 μm, a groove width of 0.27 μm, and a groove depth of 40 nm, and the land width, groove width and A second stamper having the same groove depth as that of the first stamper and having the land and groove spirals opposite to each other was manufactured.

  After the disk-shaped PET sheet and the first and second stampers are arranged concentrically, the disk-shaped PET sheet is sandwiched between the first and second stampers, and the required pressure and heat are applied to the disk-shaped PET sheet. Then, the lands and grooves formed on the first and second stampers were transferred to the front and back surfaces of the disk-like PET sheet. Thereby, a flexible disk substrate was obtained.

  After covering the area of 2 mm on the outer periphery of the disk substrate with two mask members from both the front and back sides, this was carried into a sputtering apparatus to form a magnetic domain expansion reproduction type recording film. The film configuration and the film formation order are as follows. That is, the SiN dielectric film for improving the adhesion between the disk substrate and the recording layer is 10 nm, the recording magnetic field assist layer enabling recording of information with a small recording magnetic field is 50 nm, the SiN dielectric film is 1 nm, and the tungsten layer is 0.5 nm, TbFeCo recording layer 50 nm, GdFeCo layer 0.5 nm, TbGdFe trigger layer 10 nm, GdFeCo second reproducing layer 5 nm, GdFeCo reproducing layer 20 nm, and AlSiN layer for optical enhancement 60 nm in this order. Filmed.

  The disk substrate after film formation is taken out from the sputtering apparatus, and the disk substrate is removed from the mask member. Then, UV resin is applied to the entire front and back surfaces of the disk substrate after film formation to a thickness of 15 μm as a protective film. Solidified with a lamp. Further, diamond-like carbon as a solid lubricant was coated on the UV protective film after solidification with a film thickness of 1 nm. Thereby, a flexible optical disk was obtained.

  Finally, a metal center hub was attached to the inner diameter part of the optical disc, and a finished optical disc with a center hub was obtained.

It is sectional drawing of the optical disk which concerns on the example of embodiment. It is a top view of the center hub mounted on the optical disc according to the embodiment. It is a bottom view of the center hub mounted on the optical disc according to the embodiment. It is principal part sectional drawing which shows the lamination | stacking state of several optical disks. It is explanatory drawing which shows the other example of the convex part and recessed part which are formed in a center hub. 1 is a cross-sectional view of an optical disc cartridge according to an embodiment. 1 is a perspective view of an optical disc cartridge according to an embodiment. FIG. 2 is a configuration diagram of a drive device that records and reproduces information by mounting an optical disk taken out from an optical disk cartridge.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical disk 2 Disc substrate 3, 4 Recording film 5 Center hub 6 Convex part 7 Concave part 11 Optical disk cartridge 12 Cartridge case 13 Disc support body 13a Concave part

Claims (2)

  A flexible disc substrate and a center hub having a total thickness larger than that of the disc substrate provided at the center of the disc substrate, and a convex portion is formed on one side of the center hub, and the center hub An optical disc, wherein a concave portion for fitting the convex portion is formed on the other surface of the optical disc.   In an optical disc cartridge in which a plurality of optical discs each having a flexible disc substrate are stored in a single cartridge case in a state of being stacked in a plane direction, the optical disc is placed at the center of the flexible disc substrate. A center hub having a larger total thickness than the disk substrate is provided, a convex portion is formed on one side of the center hub, and a concave portion for fitting the convex portion is formed on the other side of the center hub. In addition, the cartridge case is provided with one of the optical discs stacked adjacent to each other using a cartridge support having a concave portion for fitting the convex portion at a predetermined position on the inner surface. The center hub is fitted by fitting the convex portion of the center hub into the concave portion of the center hub provided in the other optical disc. A plurality of optical disks stacked concentrically with contact with each other are housed in the cartridge, and a protrusion formed on the center hub of the lowermost optical disk is fitted into the recess of the disk support. Optical disc cartridge.

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