Dynamic information storage or retrieval – Specific detail of information handling portion of system – Mechanical modification or sensing of storage medium
Patent
1986-03-18
1989-11-14
Psitos, Aristotelis M.
Dynamic information storage or retrieval
Specific detail of information handling portion of system
Mechanical modification or sensing of storage medium
283 89, 283904, G11B 300
Patent
active
048812170
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a method of making an optically recorded information medium, and more particularly it is concerned with a method of making an optically recorded information medium which permits a mass reproduction at a reasonable cost and which is useful, for example, as an optical card.
BACKGROUND ART
In an optical card 1 as shown in FIG. 5, the format of recorded information is such that a main track 3 consists of a multitude of subtrack row 2, information being formed according to the presence or absence of dots thereon as shown in FIG. 6 in an enlarged view.
Several methods have been employed heretofore for reproducing recorded medium having the same information as the optical card 1 in large quantities by means of a mask having a pattern of the main track 3. For example, a first method utilizes a photoresist and an etching, where the recorded medium obtained therein has a construction that a photoresist 6 having a desired information pattern and a light reflecting layer 7 are formed on a substrate 5 and further a protective film 8 is provided thereon, as shown, for example, in FIG. 7. Then, a second method known heretofore is such that a pattern of a glossy silver 9 is formed on a substrate 5 by exposing and developing a silver emulsion in a desired pattern, and a protective film 8 is then formed thereon as shown, for example, in FIG. 8 (Japanese Pat. Laid-Open No. 49296/1981, for example). Further, a third method is that in which a photoresist exposed and developed in a predetermined pattern is plated to form a rugged stamper, and an optical card is reproduced by press method using the stamper.
The first method described above is disadvantageous in that the etching process is time-consuming and the controllability of a large surface card is poor. The second method described above is disadvantageous because silver used therein is expensive. In addition, both the first and second methods above require many steps as well as a wet process. The third method is superior in mass productivity to the first and second methods, but it is still disadvantageous in that information recording density is not raised enough because the contrast is obtained by a phase method where rugged dots are formed, the resulting regenerative output being therefore differential, and because the tolerance of defocus is small.
In view of the foregoing, the present invention provides a method of making optically recorded information medium which permits the reproduction in large quantities and at a reasonable cost as well.
DISCLOSURE OF THE INVENTION
A method of making an optically information medium relating to the present invention comprises the steps of:
preparing an optical information recording medium consisting of a substrate, a light reflecting layer, and a recording layer formed on the light reflecting layer for recording information according to the difference of optical density between exposed portion and non-exposed portion by selective exposure to ultraviolet rays;
exposing the recording layer to ultraviolet rays through a mask for exposure having a predetermined recording pattern;
cutting the recording medium including the portion of the recording layer which has recorded the recording pattern, to make an information stripe; and
fixing the information stripe on a supporting plate.
The recording medium described above may be a flexible and continuous tape, and when the recording layer is exposed to ultraviolet rays, the recording medium may be forwarded intermittently for repeating exposure.
The supporting plate may be a rigid, card-like plate of, for example, a plastic. A protective film may be optionally provided on the recording layer.
The recording layer may be a film prepared from the mixture of a material which shows photochromism upon irradiation with ultraviolet rays and a polymeric binder. The material showing photochromism may be spiropyran compounds, tetraheterofluvalene derivatives, anthracene, glass containing silver halides, hexacarbonyl compounds of metals such as Cr,
REFERENCES:
patent: 3687664 (1972-08-01), Broadbent
patent: 3832547 (1974-08-01), Silverman
patent: 3872445 (1975-03-01), Pease
patent: 3954469 (1976-05-01), Avanzado et al.
patent: 4034211 (1977-07-01), Horst et al.
patent: 4565779 (1986-01-01), Arakawa et al.
Psitos Aristotelis M.
Sony Corporation
Tomassini James E.
LandOfFree
Method of making optically recorded information medium by exposu does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of making optically recorded information medium by exposu, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of making optically recorded information medium by exposu will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1856488