JPH10143929A - Production of optical recording medium master disk, method for recording information on optical recording medium and apparatus for producti0n of optical recording medium as well as its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce an optical recording medium which allows recording of many pieces of information and makes forgery difficult. SOLUTION: The master disk of the optical recording medium (prepaid card) 26 having a recording area 28 is manufactured by executing numerical computation by a numerical arithmetic unit 14 in order to express images as holograms, driving an electron beam exposure device 18 by using the resulted data, precisely plotting the interference fringes of the holograms on a primary recording medium 20 by using an electron beam 34 and subjecting this primary recording medium 20 to an etching treatment. The method for production of the optical recording medium master disk, the method for recording the information on the optical recording medium, the apparatus for production of the optical recording medium and the processing for production are thereby provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing an optical recording medium master, a method for recording information on an optical recording medium, an apparatus and a method for manufacturing an optical recording medium, and more particularly to a prepaid card, a credit card, a cash card, and the like. In an optical recording medium.

[0002]

2. Description of the Related Art Current prepaid cards, credit cards, cash cards, and the like have a magnetic recording portion called a magnetic stripe as recording means, and have a balance and an ID (identification) number for confirming the identity of the person if necessary. The record is recorded, and the record such as the balance is changed with the use of the card in the prepaid card. Such a card as a recording medium is convenient to carry and does not involve cumbersome cash transfer, and contributes to a so-called cashless society. On the other hand, in such a card, since the recording medium is a magnetic recording layer,
The recorded contents can be easily read, and therefore, forgery is easy. For this reason, telephone cards and prepaid cards of pachinko parlors are often forged in large quantities, which is a social problem.

[0003]

In order to cope with such forgery, complicated magnetic recording systems and IC cards have been proposed in place of conventional simple magnetic recording systems, but there is a problem that the cost is high. It has not yet become widespread. Further, those using a diffraction grating or a hologram as optical recording are disclosed in JP-A-3-71383 and JP-A-5-71383.
73738 and JP-B-7-97388. These are for judging whether or not the reflection intensity of light on the hologram is a predetermined value (or not less than a predetermined value), and for detecting the reflected light as a plurality of different optical paths by a diffraction grating or a hologram. Yes, it helps to identify whether the card is legitimate (genuine) or counterfeit, but to record other complex information, such as the value of prepaid cards, PINs and card numbers on cash cards, etc. If it is not suitable, and if it is attempted to record using the technique of the above-mentioned publication, not only the manufacture of the card but also a device for reading the information (reader) becomes considerably complicated and extremely expensive, so that it is considered difficult to realize.

Accordingly, the present invention is capable of recording a large amount of information and, in producing an optical recording medium which is difficult to forge, provides a method of manufacturing such an optical recording medium master, a method of recording information on an optical recording medium, and optical recording. It is an object of the present invention to provide a medium manufacturing apparatus and a manufacturing method.

[0005]

According to the present invention, an image is represented as a hologram, an electron beam exposure apparatus is driven using the data, and the interference fringes of the hologram are precisely recorded on the recording medium by the electron beam. , And the recording medium is subjected to an etching process to produce a master optical recording medium.

That is, according to the present invention, a step of reading an image to be recorded and digitizing the image, and arithmetically processing the data obtained by the digitizing to generate data indicating the shape of a wavefront representing interference fringes in the hologram. Step, giving data indicating the shape of the wavefront to an electron beam exposure apparatus,
A method for manufacturing a master optical recording medium, comprising: a step of exposing a medium to be exposed by scanning an electron beam using data indicating the shape of the wavefront; and a step of performing etching using the medium to be exposed. You.

Further, according to the present invention, a step of reading an image to be recorded and digitizing the data, and arithmetically processing the data obtained by the digitizing to generate data indicating a wavefront shape representing interference fringes in the hologram. And providing the data indicating the shape of the wavefront to an electron beam exposure apparatus, scanning the electron beam using the data indicating the shape of the wavefront to expose the medium to be exposed, and using the medium to be exposed Manufacturing a master of an optical recording medium by performing etching, manufacturing a stamper using the master, copying a plurality of optical recording medium bodies using the stamper, and the copied optical recording medium Providing a protective layer on the recording surface of the main body.

Further, according to the present invention, a step of reading an image to be recorded and digitizing the image, and arithmetically processing the data obtained by the digitizing to generate data indicating a wavefront shape representing interference fringes in the hologram. And providing the data indicating the shape of the wavefront to an electron beam exposure apparatus, scanning the electron beam using the data indicating the shape of the wavefront to expose the medium to be exposed, and using the medium to be exposed Manufacturing an optical recording medium master by performing etching, manufacturing a stamper using the master, and duplicating a plurality of optical recording medium bodies using the stamper; A method for recording information is provided.

Further, according to the present invention, a step of imaging data to be recorded, a step of reading an image obtained in the imaging step and digitizing the image, and an arithmetic processing of the data obtained by the numerical conversion Generating data indicating the shape of the wavefront representing the interference fringes in the hologram and providing the data indicating the shape of the wavefront to an electron beam exposure apparatus, and scanning the electron beam using the data indicating the shape of the wavefront. Exposing the medium to be exposed, etching the medium to be exposed, manufacturing a master of the optical recording medium, manufacturing a stamper using the master, and using the stamper to perform a plurality of processes. Duplicating the optical recording medium main body, the method for recording information on the optical recording medium.

Further, according to the present invention, means for reading an image to be recorded and digitizing the data, and arithmetically processing the data obtained by the digitizing to generate data indicating the shape of a wavefront representing interference fringes in the hologram. Means, giving data indicating the shape of the wavefront to an electron beam exposure apparatus, means for scanning the electron beam using the data indicating the shape of the wavefront to expose the medium to be exposed, using the medium to be exposed Means for etching to produce a master of an optical recording medium, means for producing a stamper using the master, means for duplicating a plurality of optical recording medium bodies using the stamper, and the duplicated optical recording medium Means for providing a protective layer on the recording surface of the main body.

[0011]

Embodiments of the present invention will be described below with reference to the drawings, together with preferred embodiments. FIG. 1 is a block diagram schematically showing a preferred embodiment of a method for manufacturing a master optical recording medium, a method for recording information on an optical recording medium, an apparatus for manufacturing an optical recording medium, and a manufacturing method according to the present invention. The embodiment will be described on the assumption that what is finally to be produced is a prepaid card 26 as a card-type optical recording medium. A plurality of recording areas 28 are provided and arranged on the prepaid card 26. Now, assuming that character information is to be recorded in each of the recording areas 28, a signal of character information is supplied to the input terminal IN1 and input to the image signal conversion circuit 10. The image signal conversion circuit 10 converts the character represented by the code information of the input digital signal into an image signal of a two-dimensional image dot pattern (input data in FIG. 2).

This image signal is supplied to a numerical operation device 14 via a switch 12 or a multiplexer. The numerical operation device 14 obtains a numerical value for obtaining an interference fringe pattern of a hologram (holographic interferogram) without irradiating interference light from an image signal of a dot pattern of a two-dimensional image using a predetermined algorithm. FIG. 2 schematically shows this state. Preferably, a computer capable of high-speed operation is used as the numerical operation device. Deriving a hologram interference pattern corresponding to the two-dimensional image data, that is, a wavefront shape by calculation is known as a so-called CGH (Computer Generated Hologram).

The numerical operation device 14 is configured to output coordinate data corresponding to the resolution of an electron beam exposure device 18 which is a drawing device described later. Before actually performing drawing, coordinate data obtained by numerical operation is fed back and compared with input data, and recalculation is performed a plurality of times to reduce an error between the two.

An output signal of the numerical operation device 14 is converted into a signal of a predetermined format by an encoder 16 and is input to an electron beam exposure device 18. The electron beam exposure apparatus 18 is originally used to draw a circuit arrangement pattern when an IC or LSI is manufactured. Here, the interference fringe pattern (output data) shown in FIG. 20 is used to draw on. In addition, this 1
The secondary recording medium 20 is referred to as a primary recording medium 20 because it is distinguished from the optical recording medium 26 as a final product. As the primary recording medium 20, as shown in FIG. 3B, a medium obtained by applying a photoresist 32 as a photosensitive resin as a medium to be exposed on a substrate 30 such as glass is used. The primary recording medium 20 is attached to a stepper 22 (stage controller),
The stepper 22 can be moved in two directions XY on a plane perpendicular to the electron beam 34 by a signal from the electron beam exposure device 18. It should be noted that drawing with an electron beam makes it possible to draw an extremely delicate and precise pattern as compared with drawing with a laser beam used in the production of a conventional optical recording medium. It can be said that it is suitable.

The primary recording medium 20 is processed as a photomask master, a plurality of secondary recording media are produced from the primary recording medium by light exposure from the photomask master, and an optical disk is formed by using the secondary recording medium as the master. It is also possible to manufacture an optical recording medium 26 as a final product through a manufacturing process. FIG. 6 is a diagram showing a manufacturing process using such a photomask master in the order of A to J. According to the method shown in FIG. 6, since the number of exposure steps is increased as compared with the method shown in FIG. 3, the accuracy is slightly lowered, but the method is suitable for copying a large number of secondary masters.

Now, assuming that data consisting of 300 English characters (including numbers) is to be recorded on the prepaid card, character string data serially input from the input terminal IN1 is sequentially transmitted to the image signal conversion circuit 10. The digital signal is converted into an image signal, subjected to numerical calculation processing by a predetermined algorithm in a numerical calculation device 14, converted into data in a predetermined format by an encoder 16, supplied to an electron beam exposure device 18, and deflected by an electron beam. Then, drawing is performed on the primary recording medium 20. At this time, the electron beam exposure device 18
Controls the stepper 22 so that 300 recording areas 28
In the rows, the primary recording medium 20 is moved in the XY direction on a plane perpendicular to the electron beam 34 so that 100 recording areas are arranged in each row.

FIG. 4 is an enlarged view of the completed prepaid card 26, in which three rows of recording areas 28 are arranged. Each recording area 28 is 250 μm square (A = 250 μm), and the interval between adjacent recording areas 28 is also 250 μm (B = C = 250 μm).
In one recording area 28, a hologram interference fringe pattern corresponding to one character is recorded. For example, as shown in FIG. 5, a plurality of recording areas 44a, 44b,
It is also possible to record an interference fringe pattern of the same hologram corresponding to one character in 44c and 44d. In the example shown in FIGS. 1 and 4, the recording area 2
For example, if one side of a card-shaped optical recording medium having the size of a business card is effectively used, the size of one recording area 28 is set to 250 μm square as described above, and 10
More than 00 can be provided.

When the recording on the primary recording medium 20 is completed,
The primary recording medium 20 is removed from the stepper 22, and a prepaid card 26 as a final product can be obtained through a known optical recording medium (optical disk) manufacturing process 24. FIG. 3 is a view showing the irradiation of the primary recording medium 20 with the electron beam 34 by the electron beam exposure device 18 and the subsequent optical disc manufacturing process including an etching process and the like.
The process proceeds in the order of g. In FIG. 3, reference numeral 36 denotes a photoresist 3
2 is a metal plating layer generated on the uneven surface formed in 2,
The substrate 30 is removed from the state shown in e, and attached to the press member 38 as a stamper 36A as shown in f. Reference numeral 40 denotes a PC resin constituting the optical recording medium main body 40A, which is injected from the press base 42 in a molten state, and g
As shown in the figure, the stamping member 36A is formed by a pressing process in which the pressing member 38 relatively approaches the pressing base 42.
The unevenness according to the unevenness is formed. Thereafter, a protective layer (not shown) is provided on the uneven surface of the optical recording medium main body 40A.
It should be noted that the stamper 36A may not be manufactured directly from the step e of FIG. 3 but may be manufactured first by manufacturing a master disk and then by manufacturing a plurality of stampers 36A. It is necessary to manufacture the stamper 36A.

The optical recording medium manufactured according to the present invention is read by a predetermined reader, and its recorded information is read.
At this time, when the prepaid card 26 is sent in a predetermined direction, and a laser beam or the like as a reference beam, which is a coherent light beam, is irradiated on the recording area 28, the original 2
A two-dimensional image is projected. That is, when the character "A" shown in FIG. 2 is recorded, this dot pattern is projected at a predetermined position, and is captured by an image pickup means such as a CCD image pickup device and decoded to obtain the original character. Information can be reproduced.

In the above description, the case where a character signal is inputted to the input terminal IN1 of FIG.
May be given an image signal. In this case, the image signal is supplied to the numerical operation device 14 via the switch 12, and the numerical operation is executed in the same manner as described above, so that the data of the interference pattern of the hologram is obtained. By irradiating the prepaid card 26 with a laser beam or the like, the original image can be reproduced.

[0021]

As described above, according to the present invention, an optical recording medium is manufactured by recording character or image information as a pattern of interference fringes of a hologram by an electron beam.
Compared to drawing with a laser beam used in the manufacture of conventional optical recording media, it is possible to draw extremely delicate and precise patterns, and it is extremely costly to duplicate and manufacture counterfeit products. This makes it difficult to actually produce the replica. Also, since characters and images can be recorded in a small area, an extremely large amount of information can be recorded when recording information on a card-shaped optical recording medium of about business card size. In addition, by comparing the reproduced signal with a predetermined signal based on the combination of characters to be recorded and the specificity of a specific image, a legitimate card and a counterfeit product can be easily identified.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically showing a preferred embodiment of a method for manufacturing a master optical recording medium, a method for recording information on an optical recording medium, an apparatus for manufacturing an optical recording medium, and a manufacturing method according to the present invention.

FIG. 2 is a diagram showing a procedure for obtaining an interference fringe pattern of a hologram from a two-dimensional image.

FIG. 3 is a cross-sectional view showing a manufacturing process of the optical recording medium according to the present invention.

FIG. 4 is a partially enlarged top view of an optical recording medium manufactured according to the present invention.

FIG. 5 is a diagram showing another configuration of the recording area of the optical recording medium manufactured according to the present invention.

FIG. 6 is a sectional view showing another manufacturing step of the optical recording medium according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Image signal conversion circuit (means for digitizing) 12 Switch 14 Numerical calculation device (means for generating data) 16 Encoder 18 Electron beam exposure device (means for exposing) 20 Primary recording medium 22 Stepper 24 Optical recording medium (optical disc) Manufacturing process (means for manufacturing a master, means for manufacturing a stamper, means for copying, means for providing a protective layer) 26 Optical recording medium 28, 44a, 44b, 44c, 44d Recording area 30 Substrate 32 Photoresist (medium to be exposed) 34 Electron beam 36 Metal plating layer 36A Stamper 38 Press member 40 PC resin 40A Optical recording medium main body 42 Press base IN1, IN2 Input terminal

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Kanji Kanuma 3-12-12 Moriyacho, Kanagawa-ku, Yokohama, Kanagawa Prefecture Inside (72) Inventor Kazunori Namiki 3-12 Moriyacho, Kanagawa-ku, Yokohama, Kanagawa Address Inside Victor Company of Japan, Ltd.

Claims (5)

[Claims] 1. a step of reading an image to be recorded and digitizing the image; calculating the data obtained by the digitizing to generate data indicating a shape of a wavefront representing an interference fringe in the hologram; Giving the data indicating the shape of the electron beam exposure apparatus, scanning the electron beam using the data indicating the shape of the wavefront to expose the medium to be exposed, and etching using the medium to be exposed A method for producing a master optical recording medium, comprising: 2. A step of reading an image to be recorded and digitizing the image; a step of performing arithmetic processing on the data obtained by the digitizing to generate data indicating a shape of a wavefront representing an interference fringe in the hologram; Applying the data indicating the shape of the wavefront to the electron beam exposure apparatus, scanning the electron beam using the data indicating the shape of the wavefront to expose the medium to be exposed, and performing optical etching by using the medium to be exposed to perform etching. Manufacturing a master of the medium; manufacturing a stamper using the master; copying a plurality of optical recording medium bodies using the stamper; and recording the recording surface of the copied optical recording medium main body. Providing a protective layer on the optical recording medium. 3. A step of reading an image to be recorded and digitizing the image, a step of arithmetically processing the data obtained by the digitization, and generating data indicating a shape of a wavefront representing an interference fringe in the hologram; Applying the data indicating the shape of the wavefront to the electron beam exposure apparatus, scanning the electron beam using the data indicating the shape of the wavefront to expose the medium to be exposed, and performing optical etching by using the medium to be exposed to perform etching. A method of recording information on an optical recording medium, comprising: manufacturing a master disk of a medium; manufacturing a stamper using the master disk; and copying a plurality of optical recording medium bodies using the stamper. 4. A step of imaging data to be recorded, a step of reading an image obtained in the imaging step, and a step of digitizing the data, and a step of performing arithmetic processing on the data obtained by the digitization to cause interference in a hologram. Generating data indicating the shape of the wavefront representing the fringes, providing the data indicating the shape of the wavefront to an electron beam exposure apparatus, and scanning the medium to be exposed by scanning an electron beam using the data indicating the shape of the wavefront. Exposing, etching using the medium to be exposed, manufacturing a master of an optical recording medium, manufacturing a stamper using the master, and using a plurality of optical recording medium main bodies using the stamper. Replicating the information on an optical recording medium. 5. Means for reading an image to be recorded and digitizing the data, means for performing arithmetic processing on the data obtained by the digitization, and generating data indicating the shape of a wavefront representing interference fringes in the hologram; Means for exposing the medium to be exposed by scanning an electron beam using the data indicating the shape of the wavefront to the electron beam exposure apparatus, and performing optical etching by using the medium to be exposed. Means for manufacturing a master of a medium; means for manufacturing a stamper using the master; means for copying a plurality of optical recording medium bodies using the stamper; and a recording surface of the copied optical recording medium body. Means for providing a protective layer on the optical recording medium.