JPH04254974A - Optical recording card with built-in rotary type recording medium - Google Patents

Abstract

PURPOSE:To prevent dust from generating inside a card-shaped case by constructing the card-shaped case so that the recording face of the rotary type recording medium housed in the card-shaped case can not come into contact with the irradiation part of optical energy by means of a retention part. CONSTITUTION:A thin optical disk 1 is built in a case 3 made by opaque plastic or metal. A retention part 6 is provided in the case 3 and come into contact with the outer circumference part of the disk 1 so that the surface of the disk 1 can be prevented from directly contacting an opaque part 5 of the case. Thus, the dust can be prevented from generating inside the case which can be otherwise caused by the contact, and the reliability of the optical recording card can be improved.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compact, large-capacity, personal-use optical recording medium in optical recording technology for recording high-density information using a laser.

0002

[Prior Art] Optical recording media represented by optical discs are
Recording, reproducing, and erasing information is performed by focusing a laser or other light beam to the diffraction limit. This allows very high-density information storage.

[0003] Such large-capacity memories have been developed mainly for use as auxiliary memories for large-sized computers. On the one hand, laptop computers, and even more downsizing palmtops.
2. Description of the Related Art Small, lightweight, and easily portable computers, as exemplified by computers, are becoming increasingly popular in daily life. Such small-sized computers are required to handle not only code data, which conventional computers mainly handle, but also multimedia such as images and document data. Furthermore, the quality and quantity of data handled from keyboard input to screen input has become more diverse and larger in size, contrary to the miniaturization of computer bodies. Floppy disks are currently used as a typical removable medium memory used in such small computers, but their storage capacity is small, so it is important to replace floppy disks in preparation for the future diversification of information as mentioned above. There is a need for new interchangeable memories with high density and sufficient capacity.

For example, with regard to miniaturization, an optical card with excellent portability has been proposed. Optical cards are more portable than optical disks, and are useful as small, thin, and relatively large-capacity memories. The problem was that the data transfer speed was very slow. A device that solved these problems with optical cards was published in 1983.
There is a publication No.-79581. The present invention relates to a card having a rotary recording medium sheet, such as an optical disk, provided inside the card and having a thickness comparable to that of a conventional cash card. Because this card records on a rotating recording medium, it has the advantage of significantly faster data transfer speeds than conventional optical cards, and at the same time has the portability and ease of handling of optical cards. It is.

On the other hand, conventional optical discs are housed in a cartridge case, and a shutter provided in a part of the case is opened and closed in a disc drive to irradiate the disc with a laser beam. The optical disc is housed in a cartridge case in order to prevent dust from adhering to the surface of the optical disc in the living environment and to facilitate loading and filling the disc into a drive. However, the robust cartridge is thick;
The drawback was that it was heavier overall. To make the cartridge case thinner, for example, Japanese Patent Application Laid-Open No. 60-79581
As stated in the publication, it is necessary to further reduce the thickness of the optical disk itself from the current thickness of 1.2 mm. However, as the thickness of the substrate and the case that houses it becomes thinner, the influence of scattering from dust adhering to the disk surface on the laser beam collection increases, resulting in a decrease in recording power, read errors during signal reproduction, etc. Deterioration during recording and reproduction is more likely to occur. In addition, insufficient mechanical strength causes various adverse effects such as decreased retention. Dust attached to the disk surface that causes deterioration in recording and reproduction includes dust that enters the case from the outside and dust that is generated inside the case. The intrusion of dust from the outside can be solved by completely enclosing the optical disc inside the case, as disclosed in, for example, Japanese Patent Laid-Open No. 60-79581. However, the above invention could not solve the problem of dust generated inside the case. Furthermore, JP-A-60
In Publication No. 79581, a case for storing an optical disk is made thin to the same thickness as a credit card. Since the recording medium is rotated inside such a thin case, contact or collision between the inside of the case and the built-in rotary recording medium is unavoidable. In particular, contact between the laser irradiation part provided on the case from the outside and the surface of the recording medium must be avoided because there is a risk of damaging the laser irradiation part and the recording medium surface. In Japanese Patent Application Laid-open No. 60-79581, damage caused by such contact or collision could not be solved. Furthermore, since the case is thin, it is necessary to consider damage to the recording medium due to distortion of the case during holding.

[0006]

[Problems to be Solved by the Invention] The problem to be solved by the present invention is to solve the problem of dust generated inside the card in a card-shaped memory containing a rotary recording medium described in Japanese Patent Application Laid-Open No. 60-79581. The purpose of the present invention is to prevent damage caused by contact and collision between the recording medium and the card-like case during driving, and to reduce the mechanical strength of the case. It is to provide a card.

[0007]

[Means for Solving the Problems] FIG. 1 shows a sectional view of an optical recording card incorporating a rotary recording medium according to the present invention. In this example, it is an optical recording card that has an optical disk 1 that is thinner than the thickness of the case inside a case 3 made of opaque plastic or metal. A transparent portion 5 is provided that has good translucency to light of different wavelengths. The built-in optical disc 1 has a fixed hub 2 for connection to an external drive system. The case is also provided with an identifier 4 for identifying the front and back sides. FIG. 1 also shows the cross-sectional structure of the card. As shown in the cross-sectional view, there is a space inside the case to accommodate the optical disc. As shown in FIG. 2, since the outer circumference of the optical disc 1 and the holding part 6 of the case are in contact with each other, the surface of the optical disc does not directly contact the transparent part of the case. The shape of the holding portion 6 shown in FIG. 2 has the advantage that the area of contact with the surface of the optical disk can be reduced in order to support and hold the outer peripheral corners of the optical disk 1. The present invention solves this problem by providing a holding section 6 to keep the stored optical disk 1 floating above the case transparent portion 5. In FIG. 3, holding parts 6 with different shapes are shown.
An example was shown. In this example, the contact area between the holder 6 and the optical disk 1 is larger than in the case of FIG. 2, but there is an advantage that the processing of the holder can be simplified. Figure 4 includes Figures 2 and 3.
In contrast to the case where the holding part 6 and the optical disc 1 were in contact with each other by natural grounding due to gravity, a magnet 7 is used in the holding part, and a metal plate 8 installed on the outer periphery of the optical disc 1 is pulled from above and below by magnetic force. This allows the optical disc 1 to be placed in the space inside the case.
It has a structure that keeps it afloat. This structure has the advantage of being resistant to collisions between the case and the optical disc due to vibrations applied during transportation.

[0008]

[Operation] The operation of the present invention shown in FIGS. 1 to 4 will be explained. The present invention utilizes the structure shown in FIG.
An unresolved problem is solved with a card-like memory in which a rotary recording medium is enclosed, which is described in Japanese Patent No. 0-79581. FIG. 5 shows changes in the relative position between the optical disc 1 and the transparent portion 5, which is the laser incidence part, when the optical recording card according to the present invention is not installed and when it is installed in the drive. Even when the optical disk is not mounted, the surface of the optical disk is always maintained at a distance from the transparent portion 5, and damage such as scratches and cracks due to contact between the optical disk and the transparent portion can be completely prevented. Furthermore, it is possible to suppress the generation of very small dust particles that are generated when the plastic case or optical disc substrate is scraped by contact, but which have an optical effect. Figure 5 also shows the state in which it is attached to the drive. In the mounted state, the optical disc 1 is pushed up from the holding part 6 by the spindle motor 13 and the hub chuck 9. With this positional relationship, the optical disc rotates at high speed inside the case. Japanese Patent Publication No. 1986-795
Although the card-shaped memory containing the rotary recording medium described in Publication No. 81 has the same basic operating conditions, the optical disk may be subject to surface runout during rotation due to the chucking condition of the hub chuck or the amount of initial warping of the substrate. There is a high possibility that the optical disc will come into contact with the transparent portion 5 of the case and be damaged, and no active measures have been taken to avoid this. In the present invention, even if a large surface runout occurs, the holding part 6 can completely avoid contact damage to the transparent portion 5 of the optical disc 1. Furthermore, in general, the outer circumference of an optical disk that rotates at high speed in a closed or narrow space has a higher linear velocity than the inner circumference, so the air pressure tends to be lower at the outer circumference than at the inner circumference. Because of this pressure difference,
Surface runout in the circumferential direction of the optical disc is likely to be excited. especially,
This effect is likely to occur when the optical disk itself is thin and flexible, such as the card-shaped memory enclosing a rotary recording medium described in Japanese Patent Application Laid-Open No. 60-79581. In the present invention, since the space at the outer circumference is narrowed by the holding portion 6, it is possible to alleviate the difference in pressure between the inner circumference and the outer circumference. Therefore, the holding part 6 completely prevents damage caused by contact between the built-in optical disc and the transparent part of the case, whether in the uninstalled or installed state, and also contributes to stable rotation of the optical disc in a narrow space during high-speed rotation. There is.

FIGS. 6, 7 and 8 show the storage state of the optical disc according to the holding state of the present invention. A feature of the present invention is that the optical disk is housed without contacting the transparent portion of the case in both the normal holding state shown in FIG. 6 and the tilted holding state shown in FIGS. 7 and 8.

FIG. 9 shows an invention in which a center holding portion 14 is also provided in the transparent portion corresponding to the inner peripheral portion of the optical disc. The present invention is characterized in that the optical disc is held at two locations: the inner circumference and the outer circumference. It was confirmed that the above-mentioned effect was effectively expressed in the present invention as well, and similar effects were brought about.

[0011]

[Example 1] Fig. 1 shows an example of the present invention. Case 3 was made by laminating two sheets of ABS resin with a thickness of 1.0 mm and cutting out the transparent part. The built-in optical disc 1 has a recording track of 1.8 μm.
2 inch (approx. 50 mm) track grooves with a pitch of 6 μm
mm) diameter polycarbonate substrate (thickness: 0.5 mm)
ZnS-SiO2 dielectric film of 70 nm, In3SbT
e2 recording film of 30 nm, ZnS-SiO2 dielectric film of 70 nm, gold reflective film of 200 nm, and SiO2 film of 30 nm.
0 nm layers are sequentially stacked by RF sputtering. This optical disc 1 was overwritable when the irradiation laser power was 10 mW during recording and 6 mW during erasing. The transparent part 5 of the case (about 51 mm in diameter) is made of acrylic resin and has a thickness of 0.3 mm, and is then fitted into the case and then bonded to the case 3 by ultrasonic bonding. At the center of this acrylic disc is a center hole into which a hub chuck 9 for connection with a spindle motor 13 is inserted. The holding part 6 and the identifier 4 were integrally molded into the shape shown in the figure when manufacturing the case by the injection method. In this implementation, the optical disc was irradiated with a laser through the transparent part 5, and the disc rotation speed was 3600 rpm, and the frequency was 2 MHz.
It was confirmed that overwriting of a 3 MHz sine wave signal was performed, and it was demonstrated that it functions normally as a recording medium. As one of the environmental tests during use of this example, a medium damage test was conducted by a card drop test. In the drop test shown in FIG. 10, the error occurrence rate during data reproduction was investigated when vertical drops were repeated from 3 meters above the concrete surface. As a target experiment, the same test was conducted on an optical recording card that does not have the holding part 6, which is different from the product of the present invention. In a drop test of 1 million times, no errors were observed in this example, but in the comparison product without the holding part 6, damage occurred to the transparent part after 10,000 drops, and errors occurred during data playback. started to occur. This example proves that the holding part 6 is sufficiently effective against drop impact.

(Embodiment 2) FIG. 3 shows an embodiment in which the shape of the holding portion 6 is different from that shown in FIG. In this example, a rectangular holding portion was manufactured. This embodiment is characterized in that the optical disc 1 is held by a contact surface. The stored optical disc 1 is a CD. In the drop test of Example 1, it was found that the holding part according to this example had sufficient effects.

(Embodiment 3) FIG. 4 shows a different embodiment of the holding mechanism from FIGS. 2 and 3. In this embodiment, a pair of upper and lower magnets 7 magnetically attract a metal plate (ferritic stainless steel: 0.05 mm thick) provided on the outer periphery of the optical disk 1 from above and below, thereby causing the optical disk 1 to levitate in space. The surface of the optical disc 1 is prevented from coming into contact with the transparent portion 5. 0.1mm for the magnet
A thick NdFeB strong magnet was used. The optical disc of this example uses a write-once optical disc (hereinafter referred to as WROM) in which a naphthalocyanine-based organic dye is coated on a polycarbonate substrate.The holding mechanism of this example also has the same effect as Examples 1 and 2. I found out that I can get it.

(Embodiment 4) FIG. 5 shows the optical recording card of the present invention installed in a disk drive. The memory card 10 of the present invention is magnetically fixed to a spindle motor 13 via a hub chuck 9. The hub 2 is made of stainless steel and is embedded in the core hole of the optical disc 1. In the present invention, by embedding the hub 2,
contact with the transparent portion 5 is prevented. When the memory card 10 is installed, a laser 12 is irradiated onto the optical disk 1 from the optical head 11 through the transparent portion 5, and signals are reproduced, recorded and reproduced, or recorded and reproduced and erased, etc., depending on the type of the built-in optical disk. be able to.

(Embodiment 5) FIG. 9 shows one embodiment of the present invention. In this embodiment, a center holding part 13 and a holding part 6 on the outer periphery are used.
It is characterized by the following. These two holding parts are integrally molded from the same acrylic resin as the transparent part 5 by an injection method. The transparent portion 5 and the case made of aluminum were bonded using an adhesive. The built-in optical disk is a magneto-optical disk with a thickness of 0.5
100 nm of aluminum nitride on a 100 mm glass substrate;
TbFeCo alloy 30nm, aluminum nitride 100n
200 nm thick Si-Ti alloy reflective film and 200 nm thick SiO2 protective film were sequentially laminated by RF sputtering method. In this example as well, good retention was achieved both in the state of not being attached to the drive and in the state of being attached. Further, in the drop test of Example 1, it was found that the holding part according to this example was also sufficiently effective.

[0016]

Effects of the Invention According to the present invention, in an optical recording card incorporating a rotary recording medium, by providing a holding portion in the space for storing an optical disk or the like inside the card, the optical disk surface and the card's laser beam can be transmitted through the card. By always avoiding contact with optical or transparent parts, dust generation inside the card due to contact, collisions during rotation, and circumferential surface runout caused by pressure differences between the inner and outer circumferences during high-speed rotation can be avoided. Since it is possible to effectively prevent or alleviate such problems, it has the effect of greatly improving the reliability of the optical recording card.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of one embodiment of the present invention.

FIG. 2 is a cross-sectional view of one embodiment of the holding portion of the present invention.

FIG. 3 is a sectional view of a second embodiment of the holding part of the invention.

FIG. 4 is a sectional view of a third embodiment of the holding part of the invention.

FIG. 5 is an explanatory diagram of the drive of the present invention when it is not installed and when it is installed.

FIG. 6 is a cross-sectional view in a held state.

FIG. 7 is a cross-sectional view in a held state.

FIG. 8 is a cross-sectional view in a held state.

FIG. 9 is an explanatory diagram of the drive of the present invention when it is not attached to the drive and when it is attached to the drive.

FIG. 10 is an explanatory diagram of changes in the number of falls and error occurrence rate.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1... Optical disk, 2... Fixed hub, 3... Plastic (or metal) case, 4... Identifier, 5... Transparent part, 6... Holding part, 7... Magnet, 8... Metal plate, 9... Hub chuck, 1
0...Memory card, 11...Optical head, 12...Laser,
13... Spindle motor, 14... Center holding part.

Claims (7)

[Claims] 1. A rotary recording medium on which signals are recorded, erased, or reproduced by irradiation with light energy is stored in a space provided inside a card-like case made of a metal or plastic with retention properties, and the card-like case A holding portion for the rotary recording medium is provided in the space so that the surface of the rotary recording medium does not come into contact with the light energy irradiation portion provided in the card-like case. An optical recording card with a built-in rotary recording medium. 2. A rotary recording medium on which signals are recorded, erased, or reproduced by irradiation with light energy is stored in a space provided inside a card-like case made of a metal or plastic that has a retaining property, and the card-like case The surface of the rotary recording medium corresponds to the outer periphery of the rotary recording medium in the space so that the surface of the rotary recording medium does not come into contact with the light energy irradiation portion provided in the card-like case. An optical recording card incorporating a rotary recording medium, characterized in that at least one pair of holding parts is provided at one position. 3. A rotary recording medium on which signals are recorded, erased, or reproduced by irradiation with light energy is stored in a space provided inside a card-like case made of a metal or plastic with retention properties, and the card-like case The surface of the rotary recording medium corresponds to the outer periphery of the rotary recording medium in the space so that the surface of the rotary recording medium does not come into contact with the light energy irradiation portion provided in the card-like case. An optical recording card incorporating a rotary recording medium, characterized in that a pair of magnets are provided above and below the position of the rotary recording medium, and a pair of magnetizable metal plates are provided above and below the outer peripheral portion of the rotary recording medium housed therein. . 4. A rotary recording medium on which signals are recorded, erased, or reproduced by irradiation with light energy is stored in a space provided inside a card-like case made of a metal or plastic with retention properties, and the card-like case The surface of the rotary recording medium corresponds to the outer periphery of the rotary recording medium in the space so that the surface of the rotary recording medium does not come into contact with the light energy irradiation portion provided in the card-like case. An optical recording card incorporating a rotary recording medium, characterized in that at least a pair of holding parts are provided at positions corresponding to the position and the inner peripheral part. 5. The rotary recording medium according to claim 1, 2, 3, or 4, wherein the rotary recording medium is a rotary optical recording disk that reproduces, records and reproduces signals, or reproduces and erases signals by irradiating laser energy. Optical recording card with built-in. 6. The card-like case according to claim 1, 2, 3 or 4 is made of a highly translucent plastic resin or an opaque material having a highly translucent window on at least one side and at one location. Constructed from metal or plastic resin,
An optical recording card with a built-in rotary recording medium provided with a center hole for connecting an external drive device and the rotary recording medium. 7. The rotary recording medium according to claim 1, 2, 3, or 4, is an optical recording card incorporating a rotary recording medium provided with a hub disk for connection to an external drive device.