JPH01286172A - Information recording and reproducing device and information recording medium - Google Patents

Abstract

PURPOSE:To heighten capability to keep the secrecy of data by enciphering a bit pattern recorded on the data recording part of an information recording medium by a key word and an equation. CONSTITUTION:When recording is performed, the key word KEY and the equation EQU are indicated to an MPU23, and a computed result is sent to a modulation/demodulation circuit 29, and a light source 7 is driven by the output of the circuit, and it is recorded on the data recording part of an optical card 1. A G mark 19 is provided between the tracking tracks (51 and 52) on the card 1, and the KEY and the EQU are recorded on the extension line of the mark 19 in a pre-format. Next, when reproduction is performed, the KEY and the EQU are read from an auxiliary data part 20. At this time, read data can be obtained from the data recording part. By taking the E-OR of the read data and the KEY, the data can be reproduced from the bit pattern.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to an information recording/reproducing device and an information recording medium, and particularly to an information recording medium having a data recording section and an auxiliary data section, and an information recording medium for the recording medium. The present invention relates to an information recording and reproducing device for recording and/or reproducing information.

[Prior Art] Conventionally, various types of information recording media such as disk-shaped, card-shaped, tape-shaped, etc. are known as information recording media for recording information using light, magnetism, etc., and for reading recorded information. . Among these, optical information recording media formed in the form of cards (
2. Description of the Related Art Optical cards (hereinafter referred to as optical cards) are expected to be in great demand as mediums that are small, lightweight, convenient to carry, and have a large storage capacity.

FIG. 12 is a schematic plan view of the optical card, and FIG. 13 is a partially enlarged view thereof.

In FIG. 12, 1 is an optical card, 3 is an information track,
2 is the home position. Information is recorded on the above-mentioned optical card l as an optically detectable recording pit row (information track) by scanning the optical card with a light beam that is modulated according to recorded information and focused on a minute spot. .

At this time, in order to accurately record and reproduce information without causing problems such as crossover of the information tracks 3, it is necessary to control the irradiation position of the light beam in a direction perpendicular to the scanning direction (auto tracking, hereinafter referred to as AT). It is necessary to do so. Furthermore, in order to stably irradiate a minute spot despite the bending or mechanical error of the optical card, it is necessary to perform control (autofocusing, hereinafter referred to as AF) in a direction perpendicular to the optical card.

Next, a method of recording or reproducing on an optical card will be explained using FIG. 12.

First, the light beam is at home position 2. Next, the light beam moves in the direction shown in the figure, finds the information track 3N to be recorded or reproduced, scans the information track 3N in the direction F in the figure, and Record or play back.

Here, as a means for detecting whether or not the target information track is a target information track, as shown in FIG. A method is adopted in which a number recording area (hereinafter referred to as preformat) 4 is provided, the recorded track number is read, and the contents are inspected to determine whether it is the target track or not. , 31, -) including the track number is recorded as write data,
To detect the track number, a method is adopted in which the information track is once reproduced, the track number part is extracted, and the target track number is compared with the track number.

[Problems to be Solved by the Invention] By the way, in recording media such as optical cards and optical disks, even if the recorded information is minute, it is recorded in information pits that can be observed using a magnifying means such as a microscope. hand,
Although it requires a lot of effort, by analyzing the bit pattern, the recorded information can be understood. That is, there was a drawback that the ability to maintain data confidentiality was low.

[Means for Solving the Problems] In view of the above-mentioned problems of the prior art, it is an object of the present invention to provide a recording system in which it is extremely difficult to know the recorded data, and which can improve the ability to maintain data confidentiality. The purpose of the present invention is to provide media and information recording and reproducing devices.

The information recording and reproducing apparatus of the present invention records and/or records information on an information recording medium having a data recording section and an auxiliary data section.
Or in an information recording and reproducing device that performs reproduction.

When recording information, enter keywords in the auxiliary data section,
and/or the arithmetic expression, when reproducing the data recording information, the read data which is the arithmetic result read from the data recording section and the keyword read from the auxiliary data section based on the arithmetic expression. It is characterized by performing an inverse calculation to generate the data.

Further, the information recording medium of the present invention is an information recording medium having a data recording section and an auxiliary data section, wherein the auxiliary data section has the keyword and/or the arithmetic expression, and the data recording section has the keyword and/or the arithmetic expression. It is characterized in that it has data computed by/or the above-mentioned arithmetic expression.

[Operation] According to the information recording medium and the information recording/reproducing device as described above, the bit pattern recorded in the data recording section of the information recording medium is encrypted using the keyword and the above-mentioned calculation formula, so that the information security ability is improved. is significantly improved.

[Example] Hereinafter, an information recording medium and an information recording/reproducing apparatus according to the present invention will be described in detail based on a specific example using the drawings.

An information recording/reproducing apparatus used for an optical card will be described as an embodiment of the information recording/reproducing apparatus of the present invention. In the following description, the same members will be given the same numbers.

First, the basic structure of the optical card and the structure of the optical head section will be explained.

FIG. 2 is a schematic plan view of the optical card.

In the figure, an optical card l has tracking tracks 5 (5+, 5
m, =) are arranged at equal intervals. A data recording unit 6 (61) is used to record information between each tracking track.

6,...) are provided. That is, the optical card 1 has a data recording section located between each tracking track.

FIG. 3 is an explanatory diagram of the configuration of the optical head section of the information recording/reproducing apparatus.

FIG. 4 is an explanatory diagram showing a light beam irradiated onto the optical card l.

FIG. 5 is an explanatory diagram showing the configuration of a photodetector in the optical head section.

In FIG. 3, a light beam emitted from a light source 7 such as a semiconductor laser is collimated by a collimator lens 8 and divided into three beams by a diffraction grating 10. These light beams are imaged by the objective lens 17 on the tracking tracks 5+, 5g on the optical card l and the data recording section 6, as shown in FIG.
.

Forms Sa and Ss. Here, the optical card 1 is moved in the direction of arrow R by a driving means (not shown), and is scanned by the beam spot in the direction in which the tracking track extends. Beam spots Sr, Ss, S
The reflected light of s passes through the objective lens 17 again, is reflected by the beam splitter 11, and is projected by the condenser lens system 12 onto photodetectors 13, 14, and 15, respectively. The condensing lens system 12 is an astigmatism system, and this is an example arranged so that autofocusing can be performed using a well-known astigmatism system. These photodetectors are configured in the arrangement shown in FIG.
It is divided into four parts like C and D. In FIG. 3, 9 is a prism for converting the cross-sectional distribution of the collimated light beam emitted from the semiconductor laser from an ellipse to a circular shape, and 16 is a mirror that guides the light beam to the objective lens I7.

Next, the operation of recording information on an optical card using the above-mentioned apparatus will be explained using FIG. 4. First, when recording information in the data recording section 61, the beam spot St
, Ss, and Ss are applied to the tracking track 5Is, the data recording section 6Is, and the tracking track 5, respectively. These beam spots are located on the optical card l as described above.
is scanned in the direction of arrow F. The reflected light from the beam spot Sl enters the aforementioned photodetector 13, and the reflected light from the beam spot S3 enters the photodetector 15,
The tracking signal is detected by a so-called three-beam method. That is, when the beam spots S and S are shifted relative to the tracking track 51°5, the photodetectors 13 and 1
A tracking signal is obtained by creating a difference in the intensity of light incident on the light receiving surfaces 5 and comparing the signals from these light receiving surfaces. Based on this tracking signal, beam spots St and S- are set by a tracking means (not shown) (for example, means for moving the objective lens 17 in two directions in FIG. 3).

S3 is moved together in the direction perpendicular to the scanning direction (direction D) to perform AT. The tracking track 5t,
Recording pits 18 are accurately recorded along a length of 5 m.

Next, the configuration of the optical card used in the present invention will be explained.

FIG. 6 is a schematic plan view of an example of an optical card used in the present invention.

FIG. 7 is a partially enlarged view of section A in FIG. 6.

As shown in FIGS. 6 and 7, a G mark 19 is provided between the tracking tracks 5 (51, 5s). This G mark 19 is a mark for identifying a reference track, and is preformatted and placed at a predetermined location on the optical card 1.

As shown in FIG. 7, on the extension line of the G mark 19, the keyword KEY and the arithmetic expression EQU are recorded in a preformat format, or an auxiliary data section 20 that can be recorded with a light spot is arranged. FIG. 7 shows a case where the data has already been recorded in pre-format).

In addition, in the present invention, the keyword KEY and the arithmetic expression E
QU may record only one of them.

The configuration of the information recording/reproducing apparatus of the present invention will be explained below.

FIG. 1 is a schematic diagram of an example of the configuration of an information recording/reproducing apparatus according to the present invention.

In the figure, an information recording/reproducing device t (hereinafter referred to as a drive) 21 is connected to an upper control device (hereinafter referred to as a CPU) 22, and performs data communication, control, etc. between the drive 21 and the CPU 22. MPU23 in drive 21
is ROM.

It has a built-in RAM and mainly controls the card feed dryer 24 and head feed motor 25, and the AT/AP control circuit 26.
receive the signals from the photodetectors 13, 14.15 and actuate the AP actuators 27. AT actuator 28 is driven. Further, the modulation/demodulation circuit 29 executes recording by changing the emission intensity of the light source 7 during recording, and the modulation/demodulation circuit 29 executes recording by changing the emission intensity of the light source 7 during recording, and the photodetector 1 during reproduction.
The data is demodulated based on the signal No. 4.

Note that the modulation/demodulation circuit 29 is as shown in FIG.

It consists of an 8-10 modulation/demodulation circuit 30 for the data recording section and an MFM modulation/demodulation circuit 31 for the auxiliary data section. The MPU 23 shown in FIG.
A switching signal is sent to the switch 32 to select the modulation/demodulation circuit 30 or 31. Also, a recording signal is supplied from the MPU 23 to both the modulation and demodulation circuits 30 and 31 through the signal fiber 33a, and the recording signal is supplied to the 8-1O modulation and demodulation circuit 30 or
The recording signal is modulated by the modulation/demodulation circuit 31 and drives the light source 7 through the switch 32. Similarly, the signal from the sensor 14 is supplied to the one-car modulation/demodulation circuit 30.degree. 31, and the demodulated signal is selected by the switch 34 and sent to the MPU 23 through the signal line 33c.

Next, recording and reproducing operations by the information recording and reproducing apparatus of the present invention will be explained with reference to the flowcharts of FIGS. 9 and 10, respectively.

FIG. 9 is a flowchart during recording, and FIG. 10 is a flowchart during reproduction.

During recording, step 500-11 is performed as shown in FIG.
“From the upper control device (CPtl) 22, the keyword KE
Y and the arithmetic expression EQU are instructed to the MPU 23. MPU2
3 selects the MFM modulation/demodulation circuit 31 by the signal line 33b in step 500-2, and inputs KEY and EC in the auxiliary data section.
Record U.

Next, in step 500-3, an operation is performed according to the arithmetic expression EQU using the data sent from the CPU 22 and the keyword KEY.For example, the keyword KEY is 8 bits and "
10110101”, the data unit is 8 pits and “11
010011'', and the calculation formula is EO-R (exclusive OR) for each pit in 8 bits in parallel, then the calculation result is ``011oot 10'' (see FIG. 11).

This calculation result is sent to the modulation/demodulation circuit 29 through the signal line 33a.
is sent to the 8-10 modulation/demodulation circuit 30 via the signal line 33b.
By selecting the output of the switch 32, the light source 7 is driven and the data is recorded in the data recording section of the optical card l. In step 500-4, it is checked whether the data has ended, and step 500-3 is repeated until there is no more data to record.

In the above example, in order to know the data "11010011" from the bit pattern recorded on the optical card 1, at least l) the auxiliary data section must contain the keyword KEY and the calculation formula EQ.
U is recorded.

2) The auxiliary data section is recorded using MFM modulation.

3) The keyword is 8 bits and is 10110101°.

4) The arithmetic expression is E-OR for each bit.

5) The data recording section is recorded using 8-IO modulation.

It is no exaggeration to say that it is impossible to know all of these things by observing and analyzing bit patterns with a microscope, etc., but it is possible to protect data and maintain strong data confidentiality. An information recording/reproducing device having this ability can be obtained.

Next, the operation during reproduction in this embodiment will be explained.

FIG. 1O is an example of a flowchart of operations during reproduction.

During playback, in step 600-1, KE is sent from the auxiliary data section.
Y, read EQU. At this time, the MF
The output of the M modulation/demodulation circuit 31 is selected by the switch 34. The switch 34 is switched to select the 8-10 modulation/demodulation circuit 30 to obtain read data from the data recording section. In the previous example, “01100110” is obtained as the output of the 8-1O modulation/demodulation circuit 30. Now KEY is 101
10101”, unknown data (DATA) and KE
The E-OR of each bit of Y is the read data (
READ).

DATAeKEY=READ,', DATA=READeK
From E Y, the read data “01100110” is E
By taking E-OR of ma'"10110101",
8 or more processes that can reproduce the data "11010011" are performed in Boo-2. At 600-3, the end of the data is checked, and the process at 600-2 is repeated until there is no more data to read.

[Other Examples] In the above example, the keyword KEY and the calculation formula EQU were recorded in the auxiliary data section on the track with the G mark, but they may not be included in the area for managing data (generally called a directory), for example. In this case, by changing the KEY and EQU for each file, it is possible to further improve the ability to maintain data confidentiality.

It goes without saying that the arithmetic expressions and keywords can also be easily made more complex and sophisticated than those of the embodiments described above, depending on the type of information to be handled.

[Effects of the Invention] As explained above, in the information recording medium of the present invention, it is impossible to know the recorded data by observing and analyzing the bit pattern recorded on the recording medium. It is no exaggeration to say that this has the effect of improving the ability to maintain data confidentiality.

Further, in the information recording/reproducing apparatus of the present invention, it is possible to create and/or process an information recording medium having the above functions.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an example of the configuration of an information recording/reproducing apparatus according to the present invention. FIG. 2 is a schematic plan view of the optical card. FIG. 3 is an explanatory diagram of the configuration of the optical head section of the information recording/reproducing apparatus. FIG. 4 is an explanatory diagram showing a light beam irradiated onto an optical card. FIG. 5 is an explanatory diagram showing the configuration of a photodetector. FIG. 6 is a schematic plan view of an example of an optical card used in the present invention. FIG. 7 is a partially enlarged view of section A in FIG. 6. FIG. 8 is an explanatory diagram of the modulation/demodulation circuit 29 of FIG. 1. FIG. 9 is a flowchart during recording. FIG. 10 is a flowchart during reproduction. FIG. 11 is a diagram illustrating an example of data, keywords, arithmetic expressions, and arithmetic results. FIG. 12 is a schematic plan view of the optical card. FIG. 13 is a partially enlarged view of the optical card shown in FIG. 12. l-optical card 7...light source 13, l4. l 5--Photodetector 21--
Drive 22-CP Ll 23 - Axis MPU 24 - Card feed motor 25 - Head feed motor 26 - AT/AP control circuit 27 - AF actuator 28 - AT actuator 29 - Modulation/demodulation circuit K EY -・・Keyword E Q U −・Arithmetic expression % expression % Fig. 10 Fig. 11 110100+1 Data O port 00110 Zu position WJ8L---
-----Data 8ttv doorl; Islandottne

Claims (5)

[Claims] (1) In an information recording and reproducing apparatus that records and/or reproduces information on an information recording medium having a data recording section and an auxiliary data section, when recording information, a keyword and/or the above-mentioned calculation are added to the auxiliary data section. the calculation result of the calculation formula on the data and the keyword is recorded in the data recording section, respectively, and when the information is reproduced, the read data that is the calculation result read from the data recording section and the auxiliary An information recording and reproducing apparatus characterized in that the keyword read from the data portion is inversely calculated based on the arithmetic expression to reproduce the data. (2) The information recording and reproducing apparatus according to claim 1, wherein data, keywords, and/or arithmetic expressions are recorded using different modulation methods in the data recording section and the auxiliary data section. (3) The information recording and reproducing apparatus according to claim 1, characterized in that keywords and/or arithmetic expressions are different for each data file to be recorded. (4) An information recording medium having a data recording section and an auxiliary data section, wherein the auxiliary data section has the keyword and/or the arithmetic expression, and the data recording section has the keyword and/or the arithmetic expression. An information recording medium characterized in that it has data that has been updated. (5) The information recording medium according to claim 4, wherein the keyword and/or the arithmetic expression are formed in a preformat format in the auxiliary data section.