JPS60193144A - Optical memory disk - Google Patents

Abstract

PURPOSE:To mass-produce optical memory disks without forming a thin film on hard disks, one by one, like usual by using an optical memory medium using a flexible substrate and a hard base disk 7 in combination. CONSTITUTION:The optical memory disk 1 is formed by adhering hard base disks 3A and 3B to the optical memory medium 2 obtained by laminating a recording thin film 2B on a flexible substrate 2A, and the hard base disk 3A adhered to the recording thin film 2B has light transmissivity. The substrate 2A uses any flexible material which has, specially, >=70 deg.C glass dislocation temperature. When a groove is formed in the optical memory medium, the thickness of the flexible substrate is <=20mum and the disk is sandwiched from above and below by a vacuum sealing method preferably to improve the flexibility of the optical memory medium. Information is recorded by irradiation with laser light 4 and read by irradiating the recording thin film 2B with a read light beam 5.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a source disk, and particularly to a source memory disk using an optical memory medium whose optical properties change due to the thermal energy of a laser beam.

(Conventional technology) Information is written by changing optical properties such as refractive index or reflectance using thermal energy of laser light, etc.
2. Description of the Related Art Recording media, ie, original memory media, from which information is read using optical effects are known.

Such a source memory medium has so far been Te.

Thin films made of substances such as Te compounds, thermoplastic resins, cyclic oxides, and chalcogenides are coated with glass, polymethyl methacrylate (PMMA), and the like.

Polycarbonate) (PCJ) has been formed by laminating it on a non-flexible hard substrate such as PCJ.The original disk formed in this way is excellent as a high-density recording medium capable of high-speed access. It is considered a thing.

However, when manufacturing such original memory disks, the substrate such as glass, which has been formed into the final shape, is cleaned and processed by batch vapor deposition, reactive high frequency ion blating, or spin code. Thin films must be formed one by one, making mass production impossible. %, productivity is poor when a base treatment layer or a protective layer is provided in a thin layer to create a multilayer structure, or when grooves are formed in a thin layer to facilitate tracking control or addressing. , the production cost is very high.

(Objective of the invention) In view of the problems of the above-mentioned prior art, the invention has good productivity,
Providing original memory disks with low production costs? This is the purpose.

(Structure and Main Effects of the Invention) The original memory disk according to the invention is based on a flexible kW substrate (all the recording thin films whose optical characteristics change due to the thermal energy of laser light are laminated on one side to form the entire optical memory medium). shi, ko,) 7 steps 1) Medium 4 degrees ka, uh. Sheet. Yu. 1
The holding disk (among these, at least the one that is in close contact with the recording thin film has complete light transmittance) is formed in close contact with the recording thin film.

In terms of non-invention, "flexible substrate" refers to all flexible materials such as plastics such as polyethylene terephthalate and polyimide. What does this mean, and among these materials, especially those with a glass transition temperature of 70°C or higher? When used, the surface properties are excellent and it is preferable.

In the invention, the recording thin film is Te or a Te compound.

It can be made of materials conventionally used as the original memory medium, such as thermoplastic resins, cyclic oxides, and chalcogenides. The optical memory medium must have optical properties that change sensitively depending on the thermal energy of the laser beam.

Therefore, it is necessary to form a recording thin film with a uniform and uniform surface. For this purpose, the recording thin film must be formed by vacuum evaporation on a flexible substrate held under sufficient tension at a temperature below near room temperature. .

Sputtering method 1 A method of forming a film using a reactive high frequency ion blasting method or the like is suitable.

In this way, an optical memory disk according to the invention can be obtained by sandwiching the original memory medium between the hard support disks from both sides. In the present invention, the term "rigid support disk" means a material having sufficient hardness to support an optical memory medium, molded to correspond to the disk-like shape of the final product, and made of glass or flexible material. This includes non-containing plastics (eg, PMMA, etc.).

Furthermore, in the present invention, a "grooved disk" refers to a hard support disk in which grooves corresponding to recording and reproduction grooves to be formed in the original memory medium are formed on the surface that contacts the medium. Among these hard-supported disks, those that are exposed to the recording thin film of the original memory medium must be made of transparent gold.

In the present invention, "light transmittance" refers to the ability to transmit laser light that has enough thermal energy to change the optical properties of the recording thin film during recording, and to reveal differences in the optical properties of the recording thin film during playback. This refers to the property of completely transmitting sufficient reading light. The laser light and reading light used here are similar to those used for conventional original memory disks.

When using a grooved support disk to form grooves on the original memory medium, the total thickness of the flexible substrate should be 20 μm or less in order to increase the flexibility and noise of the original memory medium, and the grooves should be formed from both the front and back using the vacuum pressure bath method. Although it is preferable to sandwich the disk, in other cases, as long as the original memory medium is supported to an extent that does not interfere with the use of the disk, any method may be used to bring the supporting disk into full contact.

By forming a recording thin film on both sides of a flexible substrate and sandwiching it between two optically transparent hard support disks,
It is also possible to manufacture entire double-sided discs that allow recording and playback on both sides.

(Effect of the invention) The original memory disk of the invention uses a combination of an original memory medium with a flexible substrate and a hard support disk, so there is no need to form a thin film on each hard disk as in the past. , it is possible to mass produce it.

Also, is the original memory medium used in non-inventions flexible? M, it can be easily molded according to the required shape of the disk. Therefore, the inventive optical memory disk can be of various shapes without compromising productivity. The grooved disk is vacuum-pressed onto a thin substrate, the original memory medium, and the grooved support disk. This makes it possible to manufacture it extremely easily.

(Embodiments) Hereinafter, embodiments of the invention will be described with reference to drawings and examples.

FIG. 1 is a side cross-sectional view of an original memory disk according to one embodiment of the invention.

The original memory disk 1 shown in this drawing is made up of an original memory medium 2 consisting of two flexible substrates laminated with a recording thin film 2Bi, which is in close contact with hard support disks 3A and 3B1.
The hard support disk 3A on which the recording thin film 2BK is secretly viewed is made of a light-transmitting goldstone.

When recording information on such an original memory disk, the laser beam 4 is irradiated, and the optical properties of the recording thin film 2B are changed according to the total information by the thermal energy thereof. The information recorded in this way is read by the reading light beam 5'i recording thin film 2B.
Optical properties obtained at that time (e.g. reflectance)
It is played by reading the changing sound.

FIG. 2 is a side sectional view showing another embodiment of the invention.

A grooved optical memory disk 11 shown in this drawing is a source memory medium 12 consisting of a flexible substrate 12A laminated with a recording thin film 1-zB2°, and a grooved hard support disk 13A (a light-transmissive layer and 13B are shown under vacuum pressure). Information can be recorded and reproduced on this disk by irradiation with a laser beam 14 and a reading light beam 15 in the same way as the disk shown in FIG.

FIG. 3 is a side sectional view showing another embodiment of the invention.

The optical memory disk 21 shown in this drawing has a flexible substrate 22
Recording thin films 22B and 22C'i are formed on the front and back sides of A.
The optically transparent hard support disks 23A and 23Bi are in close contact with the original memory medium 22 formed as a layer.

Since this disc uses an original memory medium with recording thin films on both sides, laser beams 24A and 24B and reading light beam 25A are used.

By irradiating with 25B, information '
can be recorded and played back. Alternatively, if the support disks 23A and 23B' are grooved disks, a disk with grooves on both sides can be obtained.

Hereinafter, the non-invention will be explained in detail.

Example 1 In a vacuum evaporation apparatus, seven substrates of polyethylene terephthalate film with a width of 100 mm and a thickness of 80 μm were placed in a quartz crucible containing a mixture of TeO2 and tungsten powder (ringing agent) as an evaporation layer source. It was electrically heated to about 800°C using a tungsten coil heater. The degree of vacuum in the apparatus was maintained at approximately 5 Torr.

4QcIrL/mi along the substrate film cooling can
When conveyed at a speed of n, the film thickness is 1000"i with good surface properties.
A continuous thin film of was formed on the substrate. The composition of this thin film was TeO□,□. The substrate on which this thin film was formed, that is, the original memory medium, was punched out into a circular shape, and two circular PMMs were formed.
Is the original memory disk sandwiched between A hard support disks? Obtained.

This original memory disk is Pyrex ■ or PM
A recording thin film was directly formed on a hard supporting disk such as MA and sealed with a protective substrate.It could be used as a reflectance change recording medium in the same way as a conventional original memory disk.

Example 2 Thickness of polyethylene terephthalate film t20μm
A circular original memory medium barrel containing a thin film of TeO□, 1, and two grooved circular PMs were prepared in the same manner as in Example 1, except that
An optical memory disk with grooves was obtained by vacuum-pressing both the front and back sides of the MA engraving disk. The groove shape of the support disk is well transferred to the recording thin film, allowing for tracking during recording and playback. It was easy to do. Further, other characteristics were the same as those of the disk of Example 1.

Other recording thin film materials such as GeOx, PbOx.

The original memory disk used in the original memory medium 2 obtained by forming a film of cyclic oxides such as 5bOx and MoOx or other chalcogenides on a flexible substrate by Tanimune's method was also used in Example 1 and the Example 1. As in Example 2, each material could be used equivalently to a conventional optical memory disk in which the film was directly deposited on a hard support disk.

[Brief explanation of the drawing]

1 to 3 are side sectional views showing different embodiments of the invention. 1.11,21... Original memory disk 2.12.22
...Original memory medium 2A', 12A, 22A...Flexible base plate 2B, 12B
, 22B, 22C... Recording thin film 3A, 3B, 23A,
23B...Hard support disk 13A, 13B...Grooved hard support disk 4.14.24A, 24B...
Laser source 5.15, 25A, 25B...Reading light beam iJ1Figure iI 2 Figure 3

Claims (1)

[Claims] υ An original memory medium consisting of a flexible substrate, a recording thin film laminated on one side of this substrate and whose optical characteristics change depending on the thermal energy of the laser source, and this It consists of two hard support disks that cover the entire front and back surfaces of the original memory medium. 2) The original memory disk according to claim 1, characterized in that the glass transition temperature of the substrate is 70° C. or higher. 3) The thickness of the substrate 20 μm or less, and the hard support disk is a grooved disk and is crimped onto the original memory medium. Original memory disk.