Method and apparatus for preventing illegal copy or illegal installation of information of optical recording medium

Abstract

A recording and reproducing system for performing the reproduction using an optical recording medium. A physical feature of a ROM type disk is extracted and enciphered before being recorded in an optical disk. The cipher reproduced and converted into a plain text physical feature, which in turn, is compared with the physical feature information detected from the ROM disk. When both are coincident with each other, the operation of the system stops, thereby preventing the use of an illegally duplicated disk. The physical feature information, recorded on a magnetic recording layer 4 of the optical recording medium 2, is reproduced by an optical head 8 and compared with the information measured by a physical feature information detector, thereby detecting a duplicated medium.

Claims

What is claimed is:

1. An information reproducing system comprising means (17) for rotationally driving a disc-like optical recording medium (2) wherein information is recorded in the form of pits, an optical head (6) for reading out the recorded information from said optical recording medium, head-moving means (23) for making said optical head movable radially on said optical recording medium, and signal processing means for processing the information read out through said optical head, which system is characterized by including:

first physical information detecting means (743, 38, 665) for detecting, on the basis of information read out through one of said optical head and a magnetic head, first physical feature information (532) which is representative of a physical feature including at least one of a two-dimensional pit arrangement and a pit configuration on said optical recording medium and which is enciphered and recorded at manufacturing of said optical recording medium;

decryption means (534) for deciphering the first physical feature information;

means (17a, 6, 38, 703a) for measuring a physical feature of said optical recording medium to detect second physical feature information;

check means (535) for checking said second physical feature information with said first physical feature information to make a decision as to whether or not both are in a specific relation to each other; and

control means (717, 665) for, when the check means decides that said second physical feature information is not in the specific relation to said first physical feature information, stopping one of an operation of a specific program read out from said optical recording medium, the subsequent reading-out of information from said optical recording medium, and a given process of information, read out from the optical recording medium, the given process being practiced by said signal processing means, characterized in that said decryption means (534) converts a cipher into a plain text including said first physical feature information by using a disclosed key cipher system function (695b, 698b, 735h) for a decryption calculation (698b, 735s).

2. A system as defined in claim 1, characterised in that said second physical feature information detecting means detects a coordinate position of an optical recording signal on said optical recording medium by using coordinate position detecting means (335) for the detection of said second physical feature information.

3. A system as defined in claim 2, characterised in that said coordinate position detecting means obtains said second physical feature information by using angular position detecting means (17a) designed to detect an angular position of a specific recording signal on said recording medium.

4. A system as defined in claim 3, characterised in that said coordinate position detecting means has rotation detecting means (17) for detecting the rotation of a motor to detect an arrangement angle of said recording signal.

5. A system as defined in claim 4, characterised in that said rotation detecting means comprises detecting means (17a) for detecting a rotational pulse signal from said motor.

6. A system as defined in claim 5, characterised in that said rotation detecting means detects the rotation by using time division means (737) for time-dividing said rotational pulse signal from said motor to generate rotational pulses larger in number than the pulses of said rotational pulse signal.

7. A system as defined in claim 4, characterised in that said rotation detecting means detects the rotation on the basis of a rotational pulse signal from an FG (17) mounted on said motor.

8. A system as defined in claim 1, characterised in that said second physical feature information detecting means detects said second physical feature information by using tracking displacement detecting means (554) for detecting a tracking displacement.

9. A system as defined in claim 8, characterised in that said second physical feature information detecting means obtains said second physical feature information by using angular position detecting means (553) for detecting track displacements (554) of two or more specific recording signals placed on the adjacent tracks and disposed at the same angle and arrangement angles of said recording signals.

10. A system as defined in claim 8, characterised in that said tracking displacement detecting means (24a) detects a track displacement by using tracking amount detecting means (554) for detecting reflected light from an optical recording layer by a plurality of light-receiving sections (24b, 24c) divided in a tracking direction to obtain a tracking error signal.

11. An information reproducing system comprising means (17) for rotationally driving a disc-like optical recording medium (2) wherein information is recorded in the form of pits, an optical head (6) for reading out the recorded information from said optical recording medium, head-moving means (23) for making said optical head movable radially on said optical recording medium, and signal processing means for processing the information read out through said optical head, which system is characterized by including:

first physical information detecting means (743, 38, 665) for detecting, on the basis of information read out through one of said optical head and a magnetic head, first physical feature information (532) which is representative of a physical feature including at least one of a two-dimensional pit arrangement and a pit configuration on said optical recording medium and which is enciphered and recorded at manufacturing of said optical recording medium;

decryption means (534) for deciphering the first physical feature information;

means (17a, 6, 38, 703a) for measuring a physical feature of said optical recording medium to detect second physical feature information;

check means (535) for checking said second physical feature information with said first physical feature information to make a decision as to whether or not both are in a specific relation to each other; and

control means (717, 665) for, when the check means decides that said second physical feature information is not in the specific relation to said first physical feature information, stopping one of an operation of a specific program read out from said optical recording medium, the subsequent reading-out of information from said optical recording medium, and a given process of information, read out from the optical recording medium, the given process being practiced by said signal processing means, characterized in that said second physical feature information detecting means is equipped with pit depth detecting means (555) for detecting a pit depth of a specific recording signal to detect said second physical feature information.

12. A system as defined in claim 11, characterised in that said pit depth detecting means (555) detects a shallow pit area, in which pits are shallow in depth, by using a multi-level slicer (555b) having two or more slice levels.

13. A system a s defined in claim 12, characterised in that said pit depth detecting means (555) detects a second pit group (560c) recorded after a first pit group (561a) for a specific recording signal, said first pit group having pits with a common depth, and said second pit group having pits which are shallower than pits of said first pit group.

14. A system as defined in claim 13, characterised in that a frame synchronizing signal (738) is used as said specific recording signal.

15. A system as defined in claim 12, characterised in that said pit depth detecting means reproduces a learning pit group (560a) of a first pit group to detect a first offset voltage (746) with a first slice level before setting said slice level at said first offset voltage to reproduce a second pit group (560b).

16. A system as defined in claim 12, characterised in that said pit depth detecting means (555) obtains said second physical feature information by measuring a pit length of a pit group satisfying a first slice level and a pit length of a pit group satisfying a second slice level.

17. A system as defined in claim 12, characterised in that, when a slice level for a small light quantity is set as a first slice level, said multi-level slicer (555b) receives detection signals of pits satisfying only said first slice level but not satisfying a second slice level, and said pit depth detecting means (555) obtains said second physical feature information by measuring the number of said detection signals by means of a counter (555c).

18. An information reproducing system comprising means (17) for rotationally driving a disc-like optical recording medium (2) wherein information is recorded in the form of pits, an optical head (6) for reading out the recorded information from said optical recording medium, head-moving means (23) for making said optical head movable radially on said optical recording medium, and signal processing means for processing the information read out through said optical head, which system is characterized by including:

first physical information detecting means (743, 38, 665) for detecting, on the basis of information read out through one of said optical head and a magnetic head, first physical feature information (532) which is representative of a physical feature including at least one of a two-dimensional pit arrangement and a pit configuration on said optical recording medium and which is enciphered and recorded at manufacturing of said optical recording medium;

decryption means (534) for deciphering the first physical feature information;

means (17a, 6, 38, 703a) for measuring a physical feature of said optical recording medium to detect second physical feature information;

check means (535) for checking said second physical feature information with said first physical feature information to make a decision as to whether or not both are in a specific relation to each other; and

control means (717, 665) for, when the check means decides that said second physical feature information is not in the specific relation to said first physical feature information, stopping one of an operation of a specific program read out from said optical recording medium, the subsequent reading-out of information from said optical recording medium, and a given process of information, read out from the optical recording medium, the given process being practiced by said signal processing means, characterized in that said second physical feature information detecting means (635) detects said second physical feature information with error signal detecting means (633) being used as physical feature information detecting means to detect the presence or absence of an error signal (632) of a specific recording signal in a specific address.

19. A system as defined in claim 18, characterised in that, when the number (535b) of said error signals of said specific recording signal indicated in said first physical feature information does not exceed a predetermined value (535b), said check means (535) issues a stop instruction.

20. An information reproducing system comprising means (17) for rotationally driving a disc-like optical recording medium (2) wherein information is recorded in the form of pits, an optical head (6) for reading out the recorded information from said optical recording medium, head-moving means (23) for making said optical head movable radially on said optical recording medium, and signal processing means for processing the information read out through said optical head, which system is characterized by including:

first physical information detecting means (743, 38, 665) for detecting, on the basis of information read out through one of said optical head and a magnetic head, first physical feature information (532) which is representative of a physical feature including at least one of a two-dimensional pit arrangement and a pit configuration on said optical recording medium and which is enciphered and recorded at manufacturing of said optical recording medium;

decryption means (534) for deciphering the first physical feature information;

means (17a, 6, 38, 703a) for measuring a physical feature of said optical recording medium to detect second physical feature information;

check means (535) for checking said second physical feature information with said first physical feature information to make a decision as to whether or not both are in a specific relation to each other; and

control means (717, 665) for, when the check means decides that said second physical feature information is not in the specific relation to said first physical feature information, stopping one of an operation of a specific program read out from said optical recording medium, the subsequent reading-out of information from said optical recording medium, and a given process of information, read out from the optical recording medium, the given process being practiced by said signal processing means, characterized in that said second physical feature information detecting means uses a special sign detecting means (640) as physical feature information detecting means and detects said second physical feature information by detecting that a special sign (639) which is not present in a first legal sign decode table in sign decode means exists in a specific recording signal area.

21. A system as defined in claim 20, characterised in that, when said special sign (639) is not present in said specific recording signal area indicated by said first physical feature information, said check means (535) outputs a stop instruction.

22. An information reproducing system comprising means (17) for rotationally driving a disc-like optical recording medium (2) wherein information is recorded in the form of pits, an optical head (6) for reading out the recorded information from said optical recording medium, head-moving means (23) for making said optical head movable radially on said optical recording medium, and signal processing means for processing the information read out through said optical head, which system is characterized by including:

first physical information detecting means (743, 38, 665) for detecting, on the basis of information read out through one of said optical head and a magnetic head, first physical feature information (532) which is representative of a physical feature including at least one of a two-dimensional pit arrangement and a pit configuration on said optical recording medium and which is enciphered and recorded at manufacturing of said optical recording medium;

decryption means (534) for deciphering the first physical feature information;

means (17a, 6, 38, 703a) for measuring a physical feature of said optical recording medium to detect second physical feature information;

check means (535) for checking said second physical feature information with said first physical feature information to make a decision as to whether or not both are in a specific relation to each other; and

control means (717, 665) for, when the check means decides that said second physical feature information is not in the specific relation to said first physical feature information, stopping one of an operation of a specific program read out from said optical recording medium, the subsequent reading-out of information from said optical recording medium, and a given process of information, read out from the optical recording medium, the given process being practiced by said signal processing means, characterized in that said second physical feature information detecting means has pit arrangement detecting means (747) for detecting pit arrangements on two or more tracks, adjacent to each other, in a specific area indicated by said first physical feature information of said recording medium.

23. A system as defined in claim 22, characterised in that said pit arrangement detecting means (747) detects an area in which pit arrangements on the adjacent two tracks are in phase or in antiphase with each other.

24. A system as defined in claim 23, characterised in that said pit arrangement detecting means (747) obtains said second physical feature information by detecting positional information of an inphase pit area in which the recording signal pits with the longest pit length are arranged to be in phase with each other.

25. A system as defined in claim 24, characterised by further comprising inphase/antiphase signal position detecting means (748) for detecting a position of an inphase pit area by using address information and a reproduced clock signal to obtain a portion of said second physical feature information (734).

26. A system as defined in claim 24, characterised in that said decryption means converts a first cipher into a plain text with a cipher decode function stored in an OS.

27. A system as defined in claim 23, characterised by further comprising a specific inphase signal detecting section (749) for detecting a specific inphase signal (654a) corresponding to a specific pit length on the basis of a detection signal of inphase/antiphase signal position detecting means (747).

28. A system as defined in claim 27, characterised in that said specific inphase signal detecting section (749) detects an inphase signal (654a) of a frame synchronizing signal as said specific inphase signal.

29. A system as defined in claim 23, characterised by further comprising inphase/antiphase signal position detecting means (747) for detecting inphase signals (654a, 654b) corresponding to inphase pit arrangements on adjacent three or more tracks.

30. A system as defined in claim 29, characterised in that said inphase/antiphase signal position detecting means (747) detects specific inphase signals (654a, 654b) on adjacent three tracks where the longest pits are disposed in phase as inphase signals.

31. A system as defined in claim 30, characterised by further comprising a specific inphase signal detecting section (749) for detecting an inphase signal (654a) of a frame synchronizing signal as said specific inphase signal.

32. A system as defined in claim 23, characterised by further comprising off-tracking means (646) provided in a tracking means (24) for tracking between two tracks to reproduce inphase signals or antiphase signals of pits of said two tracks, and further comprising inphase/antiphase signal detecting means (747) for detecting an inphase or antiphase area in which pit arrangements on said two tracks are in phase with each other to obtain said second physical feature information.

33. A system as defined in claim 29, characterised by further comprising off-tracking control means (646) responsive to an off-tracking switching signal from control means (10) to cause a light beam to be switch from a state of travelling one track to a state of travelling between two tracks to, reproduce inphase signals or antiphase signals of said two tracks so that said inphase/antiphase signal detecting means (747) detects said inphase signals or antiphase signals.

34. A system as defined in claim 33, characterised in that said off-tracking control means (24a, 646) inverts the polarity of a tracking servo of tracking means in accordance with said off-tracking switching signal to make switching to an off-tracking state in which said light beam travels between said two tracks.

35. A system as defined in claim 22, characterised in that said pit arrangement detecting means detects an area in which pit arrangements on adjacent two tracks are in phase with each other.

36. An information reproducing system comprising means (17) for rotationally driving a disc-like optical recording medium (2) wherein information is recorded in the form of pits, an optical head (6) for reading out the recorded information from said optical recording medium, head-moving means (23) for making said optical head movable radially on said optical recording medium, and signal processing means for processing the information read out through said optical head, which system is characterized by including:

first physical information detecting means (743, 38, 665) for detecting, on the basis of information read out through one of said optical head and a magnetic head, first physical feature information (532) which is representative of a physical feature including at least one of a two-dimensional pit arrangement and a pit configuration on said optical recording medium and which is enciphered and recorded at manufacturing of said optical recording medium;

decryption means (534) for deciphering the first physical feature information;

means (17a, 6, 38, 703a) for measuring a physical feature of said optical recording medium to detect second physical feature information;

check means (535) for checking said second physical feature information with said first Physical feature information to make a decision as to whether or not both are in a specific relation to each other; and

control means (717, 665) for, when the check means decides that said second physical feature information is not in the specific relation to said first physical feature information, stopping one of an operation of a specific program read out from said optical recording medium, the subsequent reading-out of information from said optical recording medium, and a given process of information, read out from the optical recording medium, the given process being practiced by said signal processing means, characterized by further comprising reproducing means for detecting a low-reflection section (740) producing a small reflected light quantity due to the presence of pits and a high-reflection section (741) having a higher reflectance than that of said low-reflection section due to the absence of pits, second low-reflection section detecting means (586) for detecting a second low-reflection section placed in an optical recording signal area (742) and having a lower reflectance than that of said first low-reflection section to produce a second reflected light quantity, and demodulating means (621) for demodulating a second low-reflection section detection signal of said second low-reflection section detecting means into a first digital signal.

37. A system as defined in claim 36, characterised in that level slicers having two or more slice levels are used so that said first optical recording signal is sliced with a first slice level in a first level slicer (586) to obtain said first digital signal from a first optical reproduced signal and a reproduced signal is sliced with a second slice level in a second level slicer (586), said second slice level corresponding to a light quantity smaller than that for said first slice level, whereby said second low-reflection section detecting means (586) detects said second low-reflection section.

38. A system as defined in claim 37, characterised by further comprising at least one of second low-reflection section pulse width detecting means (621e) for detecting the circumferential length of said second low-reflection section on the basis of said second low-reflection section detection signal due to said second low-reflection section detecting means (586) and said first optical reproduced signal due to said reproducing means (590) and second low-reflection section interval detecting means (621b) for detecting a circumferential interval of said second low-reflection section, said demodulating means (621) demodulating said first digital signal on the basis of a detection signal of said second low-reflection section interval detecting means.

39. A system as defined in claim 38, characterised in that, on the basis of the number of reproduction clock signals counted by a counter (598c), said second low-reflection section pulse width detecting means (621e) detects a pulse duration of a detection signal of said second low-reflection section and said second low-reflection section pulse interval detecting means (621b) detects an interval of said second low-reflection section detection signal.

40. A system as defined in claim 36, characterised in that said decryption means (534) obtains said first physical feature information by obtaining a first cipher from said first digital signal and by decrypting said first cipher.

41. A system as defined in claim 40, characterised in that said decryption means (534) encrypts said first cipher and converts at least said first physical feature information and an ID number (750) into plain texts.

42. A system as defined in claim 40, characterised by further comprising an ID outputting section (750) for obtaining and outputting an ID number, which is a plain text, from said first digital signal.

43. A system as defined in claim 40, characterised in that said demodulating means (621) outputs an ID number, which is a plain text or cipher, on the basis of said first digital signal, and further outputs a first secrete key, mathematically independent of said ID number, when a communication is established with a one direction function, and characterised by further comprising a calculation section (10) for enciphering secrete information with said first secrete key and a disclosed key cipher such as an RSA function to transmit said cipher, together with said ID number, through a communication section (664) to an external computer (633).

44. An information reproducing system comprising means (17) for rotationally driving a disc-like optical recording medium (2) wherein information is recorded in the form of pits, an optical head (6) for reading out the recorded information from said optical recording medium, head-moving means (23) for making said optical head movable radially on said optical recording medium, and signal processing means for processing the information read out through said optical head, which system is characterized by including:

first physical information detecting means (743, 38, 665) for detecting, on the basis of information read out through one of said optical head and a magnetic head, first physical feature information (532) which is representative of a physical feature including at least one of a two-dimensional pit arrangement and a pit configuration on said optical recording medium and which is enciphered and recorded at manufacturing of said optical recording medium;

decryption means (534) for deciphering the first physical feature information;

means (17a, 6, 38, 703a) for measuring a physical feature of said optical recording medium to detect second physical feature information;

check means (535) for checking said second physical feature information with said first physical feature information to make a decision as to whether or not both are in a specific relation to each other; and

control means (717, 665) for, when the check means decides that said second physical feature information is not in the specific relation to said first physical feature information, stopping one of an operation of a specific program read out from said optical recording medium, the subsequent reading-out of information from said optical recording medium, and a given process of information, read out from the optical recording medium, the given process being practiced by said signal processing means, characterized in that said decryption means (534) converts a first cipher, encrypted with a disclosed key cipher system function, into a plain text including said first physical feature information.

45. A system as defined in claim 44, characterised in that said decryption means enciphers said first cipher by using an integer d.gtoreq.256 bits as a secrete key and converts said first cipher into said plain text by using an integer n.gtoreq.256 bits as a decode key and disclosed key.

46. A system as claimed in claim 45, characterised in that said decryption means uses an RSA function as said disclosed cipher system function.

47. A system as claimed in claim 46, characterised in that, when said first cipher is taken as C, said plain text is taken as M, said disclosed key is taken to be an integer n.gtoreq.256 bits and said secrete key is taken to be an integer d above 256 bits, said decryption means obtains said first physical feature information by decoding said plain M in accordance with an equation of M=Cemod n as a function of said first cipher C made by encrypting means, a disclosed integer e above 3 and said disclosed key n in accordance with an equation of C=Mdmod n.

48. A system as defined in claim 45, characterised in that said decryption means uses an elliptical function as said disclosed key cipher system function.

49. A system as defined in claim 44, characterised in that said decryption means reproduces a plain text conversion function recorded in said recording medium, and converts a reproduced cipher into a plain text with said plain text conversion function.

50. A system as defined in claim 44, characterised in that said decryption means obtains said first physical feature information by using cipher-plain text conversion means which converts a cipher reproduced from said recording medium into a plain text by using a cipher decode function stored in a memory section of a non-volatile RAM or ROM of said system.

51. A system as defined in claim 50, characterised in that a plain text conversion function group comprising a plurality of plain text conversion functions is stored in said memory section of said system, a reproduced cipher is converted into a plain text through a plurality of specific functions of said plain text conversion function group to obtain a plurality of plain text groups, and a stop instruction is issued except that all of said plain text groups are normally obtained.

52. A method of preventing an illegal copy of a disc-like optical recording medium or of preventing an illegal install of information on the disc-like optical recording medium, which comprises the steps of:

detecting on the basis of information read out from the optical recording medium first physical feature information (532) which is representative of a physical feature including at least one of a two-dimensional pit arrangement and pit configuration on said optical recording medium and which is encrypted and recorded by using a one direction function at manufacturing of said optical recording medium;

decrypting said first physical feature information;

measuring a physical feature of said optical recording medium to obtain second physical feature information;

checking said second physical feature information with said first physical feature information to make a decision as to whether or not both are in a specific relation to each other; and

when the check step decides that the second physical feature information is not in the specific relation to the first physical feature information, stopping the operation of a specific program read out from the optical recording medium, stopping at least one of the subsequent reading-out of information from the optical recording medium, and a given process of information read out from said optical recording medium, the given process being practiced by signal processing means.

53. A method of preventing an illegal copy of a disc-like optical recording medium or of preventing an illegal install of information on the disc-like optical recording medium, which comprises the steps of:

detecting first physical feature information (532) from said optical recording medium, said first physical feature information being indicative of a physical feature at least including a two-dimensional pit arrangement or a pit configuration on the optical recording medium, encrypted using a one direction function and recorded on said optical recording medium or an original record therefor so as to be distinguishable from main information to be recorded on said optical recording medium;

decrypting said first physical feature information;

measuring a physical feature of said optical recording medium to obtain a second physical feature information;

checking said second physical feature information with said first physical feature information to make a decision as to whether or not both are in a specific relation to each other; and

when the check step decides that said second physical feature information is not in the specific relation to said first physical feature information, stopping at least one of the operation of a specific program read out from said optical recording medium, the subsequent reading-out of information from the optical recording medium, and a given process of information, read out from the optical recording medium, said given process being practiced by signal processing means.

Description

BACKGROUND OF THE INVENTION

1. Industrial Application Field

The present invention relates to prevention of illegal copies of disc-like optical recording media and prevention of illegal install of information into information processing systems or the like, and more particularly to a method and system for preventing recorded music on optical disks, as well as projected images and various sorts of programs, such as game software (softs) and computer softwares, from being illegally copied and utilized without permission of the copyrighters, and further relates to an optical recording medium incapable of copy.

2. Description of the Prior Art

In recent years, optical disks are widely being employed in a variety of fields. The optical disks are generally classified into record-possible RAM disks and record-impossible ROM disks, while the manufacturing cost of the RAM disks is from five times to ten times that of the ROM disks. Accordingly, the ROM disks tend to be chiefly used in applications that supply a large number of people with a large quantity of information, for example, an electronic publication application and a medium cost-limited application that supplies music softwares and projected image softwares. On the other hand, as obvious from CD-ROM game machines and CD-ROM contained personal computers, there is a need for a RAM function being incorporated into the ROM disks, as an extension is more being made to interactive use. Home-use systems seldom require a large RAM capacity, for which reason great interest is focused on the advent of a new medium concept capable of realizing the three conditions: a small capacity RAM function, a large capacity ROM function, and a low cost. In addition, illegal duplicates of ROM disks such as CDs are recently put in the market so that the copyrighters suffer serious damage. Thus, a countermeasure has been needed for the duplicate prevention. Moreover, a soft distribution method has come into wide spread use where a plurality of encrypted (enciphered) programs are incorporated into disks and decrypted (deciphered) through passwords, and for improving the security of the password there is a need for a different ID number being recorded in each ROM.

One possible way to realize this concept is that one magnetic recording layer is equipped on the rear surface of a ROM disk, in which case the formation cost of the recording layer is less than one-tenth that of the ROM disk itself, thus realizing a partial RAM disk without greatly raising the cost of the ROM disk. Actually, as disclosed in Japanese Patent Laid-Open Nos. 56-163536, 57-6446, 57-212642, 2-179951, in terms of ROM disks such as CD-ROM not having a cartridge, there have already been proposed approaches wherein an optical recording section is provided on a front surface of a CD-ROM and a magnetic recording section is added on the rear surface thereof. In addition, Japanese Patent Laid-Open No. 60-70543 discloses an attempt to accomplish magnetic recording by means of a combination of a disk wherein, like optical disks of amorphous material, an optical recording section, made of a non-magnetic material, is placed on its surface and a magnetic recording layer is located on its rear surface and a magnetic head which is equipped in a mechanical section facing the rear surface.

On the other hand, for the duplicate prevention, only means is known which is made to manufacture a special disk through a special process, such as intentionally making a cut or openwork on the disk, so that difficulty is encountered to manufacture it without a special manufacturing apparatus.

However, the aforesaid methods are merely based on a combination of a magnetic recording section and an optical recording section, while not containing the important requirements for definite realization of the equipment at all, such as the ways of avoiding the mutual interference between the optical recording section and magnetic recording section, permitting access to magnetic tracks with a simple arrangement, sharing a circuit, protecting magnetically recorded information on media from the external environment including magnetism and abrasion without the use of a cartridge, compressing information to be recorded in a RAM area, accelerating the access, and concretely making out a physical track format.

Furthermore, in the prior art examples, disclosure is hardly made in terms of the ways of realizing a home-use partial RAM disk in a concrete form, such as the method of mass-producing media at a low cost, which is important in realization of the media, and the method of making the media conformable with the CD standards. Therefore, there remains a problem which arises with the conventional examples in that difficulty is experienced in concrete realization of media and systems capable of home use.

SUMMARY OF THE INVENTION

The present invention is for eliminating above-described problems, and it is therefore a first object of the present invention to provide a method, system and medium which can realize a ROM type partial RAM disk and system without the use of a cartridge like a CD-ROM.

A second object of this invention is to provide a duplicate-preventing disk and system capable of preventing illegal duplicate through a way such as changing the physical arrangement of addresses, but not through the special method proposed heretofore.

For achieving these purposes, according to this invention, when an optical disk enters in a manufacturing step, first physical feature information indicative of a physical feature including at least a two-dimensional pit arrangement or pit configuration is encrypted and optically or magnetically written in advance in such a manner as being distinguishable from the main information to be recorded in the optical disk, before, i.e., when being in reproduction, read out to be deciphered. At this reproduction, a physical feature of the optical disk is additionally measured to obtain second physical feature information. The second physical feature information is checked (collated) with the first physical feature information so as to make a decision as to whether or not a specific relationship is present therebetween. When the second physical feature information is not in the specific relation to the first physical feature information, the operation of a specific program read out from the optical disk is made to stop, the reading-out of the information is designed to stop afterwards, or a given process of the read information by a signal processing means is adapted to stop.

That is, according to this invention, there is provided an information reproducing system comprising means (17) for rotationally driving a disc-like optical recording medium (2) wherein information is recorded in the form of pits, an optical head (6) for reading out the recorded information from the optical recording medium, head-moving means (23) for making the optical head movable radially of the optical recording medium, and signal processing means for processing the information read out through the optical head, which system is characterised by including:

first physical information detecting means (743, 38, 665) for detecting on the basis of information read out through the optical head or a magnetic head first physical feature information (532) which is representative of a physical feature including at least a two-dimensional pit arrangement or pit configuration on the optical recording medium and which is encrypted and recorded at manufacturing of the optical recording medium;

decryption means (534) for decrypting the first physical feature information;

means (17a, 6, 38, 703a) for measuring a physical feature of the optical recording medium to obtain second physical feature information;

check means (535) for checking the second physical feature information with the first physical feature information to make a decision as to whether or not both are in a specific relation to each other; and

control means (717, 665) for, when the check means decides that the second physical feature information is not in the specific relation to the first physical feature information, stopping the operation of a specific program read out from the optical recording medium, for stopping the reading-out of information from the optical recording medium afterwards, or for stopping a given process of information, read out from the optical recording medium, the given process being practiced by the signal processing means.

Moreover, according to this invention, there is provided an information recording system which is characterised by comprising:

encryption means (537) for encrypting, using a one direction function, first physical feature information (532) indicative of a physical feature including at least a two-dimensional pit arrangement or pit configuration on a disc-like optical recording medium; and

recording means (37, 6, 23, 24, 17, 26, 10) for recording the encrypted first physical feature information on the optical recording medium or an original record therefor so that the encrypted first physical feature information is distinguishable from main information to be recorded on the optical recording medium.

In addition, according to this invention, there is provided a method of manufacturing a disc-like optical recording medium, which comprises the steps of:

recognizing first physical feature information (532) representative of a physical feature at least including a two-dimensional pit arrangement or a pit configuration on the disc-like optical recording medium;

encrypting the first physical feature information by using a one direction function; and

recording the encrypted first physical feature information on the optical recording medium or an original record therefor so that the encrypted first physical feature information is distinguishable from main information to be recorded on the optical recording medium.

Furthermore, according to this invention, there is provided a disc-like optical recording medium which is manufactured through the steps of recognizing first physical feature information (532) representative of a physical feature at least including a two-dimensional pit arrangement or a pit configuration on the disc-like optical recording medium, encrypting the first physical feature information by using a one direction function; and recording the encrypted first physical feature information on the optical recording medium or an original record therefor so that the encrypted first physical feature information is distinguishable from main information to be recorded on the optical recording medium.

Still further, there is provided a method of preventing an illegal copy of a disc-like optical recording medium or of preventing an illegal install of information on the disc-like optical recording medium, which comprises the steps of detecting on the basis of information read out from the optical recording medium first physical feature information (532) which is representative of a physical feature including at least a two-dimensional pit arrangement or pit configuration on the optical recording medium and which is encrypted and recorded by using a one direction function at manufacturing of the optical recording medium;

decrypting the first physical feature information;

measuring a physical feature of the optical recording medium to obtain second physical feature information;

checking the second physical feature information with the first physical feature information to make a decision as to whether or not both are in a specific relation to each other; and

when the check step decides that the second physical feature information is not in the specific relation to the first physical feature information, stopping the operation of a specific program read out from the optical recording medium, stopping the reading-out of information from the optical recording medium afterwards, or stopping a given process of information, read out from the optical recording medium, the given process being practiced by signal processing means.

Moreover, there is provided a method of preventing an illegal copy of a disc-like optical recording medium or of preventing an illegal install of information on the disc-like optical recording medium, which comprises the steps of:

detecting first physical feature information (532) from the optical recording medium, the first physical feature information being indicative of a physical feature at least including a two-dimensional pit arrangement or a pit configuration on the optical recording medium, encrypted using a one direction function and recorded on the optical recording medium or an original record therefor so as to be distinguishable from main information to be recorded on the optical recording medium;

decrypting the first physical feature information;

measuring a physical feature of the optical recording medium to obtain a second physical feature information;

checking the second physical feature information with the first physical feature information to make a decision as to whether or not both are in a specific relation to each other; and

when the check step decides that the second physical feature information is not in the specific relation to the first physical feature information, stopping the operation of a specific program read out from the optical recording medium, stopping the reading-out of information from the optical recording medium afterwards, or stopping a given process of information, read out from the optical recording medium, the given process being practiced by signal processing means.

CONTENTS OF THIS SPECIFICATION

This specification contains detailed descriptions of many embodiments, and a table of the brief contents thereof is herein appended as follows.

    ______________________________________
    Summary of the Invention
                            .cndot. .cndot. .cndot. P2-P7
    Brief Description of the Drawings
                            .cndot. .cndot. .cndot. P7-P14
    Description of Reference Marks
                            .cndot. .cndot. .cndot. P14-P30
    Table of Contents of the Embodiments and
                            .cndot. .cndot. .cndot. P31
    Corresponding Drawings
    First Embodiment        .cndot. .cndot. .cndot. P32
    Second Embodiment       .cndot. .cndot. .cndot. P39
    Third Embodiment        .cndot. .cndot. .cndot. P52
    Fourth Embodiment       .cndot. .cndot. .cndot. P59
    Fifth Embodiment        .cndot. .cndot. .cndot. P65
    Sixth Embodiment        .cndot. .cndot. .cndot. P67
    Seventh Embodiment      .cndot. .cndot. .cndot. P70
    Eighth Embodiment       .cndot. .cndot. .cndot. P75
    Ninth Embodiment        .cndot. .cndot. .cndot. P80
    Tenth Embodiment        .cndot. .cndot. .cndot. P81
    Eleventh Embodiment     .cndot. .cndot. .cndot. P81
    Twelfth Embodiment      .cndot. .cndot. .cndot. P82
    Thirteenth Embodiment   .cndot. .cndot. .cndot. P87
    fourteenth Embodiment   .cndot. .cndot. .cndot. P92
    ______________________________________

    ______________________________________
     1         recording and reproducing system
     2         recording medium
     2M        original record
     3         magnetic recording layer
     4         optical recording layer
     5         optical transmission layer
     6, 6M     optical head
     7         optical recording block
     8         magnetic head
     8a        main magnetic pole
     8b        magnetic sub-pole
     8c        head cap
     8e        uniform magnetic field area
     8m        magnetic field modulation magnetic head
     8s        canceling magnetic head
     9         magnetic recording block
     10M       system control section
     17, 17M   motor
     18        optical head
     19        head base
     23, 23M   head moving actuator
     23a       traverse actuator
     24a       traverse movement circuit
     24, 24M   tracking circuit
     30        memory
     34a       memory (for system)
     37        optical recording circuit
     37a       time base circuit
     37b       optical recording section
     37c       optical output section
     37d       combination section
     38        frame synchronizing signal
     38a       clock reproduction circuit
     40        coil
     40a       magnetic field modulation coil
     40b       magnetic recording coil
     40c       tap
     40d       tap
     40e       tap
     41        slider
     42        disk cassette
     43        printing ground layer
     44        printing area
     45        printing
     46        pit
     47        substrate
     48        optical reflective layer
     49        printing ink
     50        protective layer
     51        arrow
     52        optical recording signal
     54        lens
     57        light-emitting section
     60        adhesive layer
     61        magnetic recording signal
     65        optical track
     66        focal point
     67        magnetic track
     67a       recording magnetic track
     67b       reproduction magnetic track
     67s       servo magnetic track
     67f       guard band
     67g       guard band
     67x       cleaning track
     69        high .mu. magnetic layer
     70        head gap
     70a       recording head gap
     70b       reproduction head gap
     81        interference layer
     84        reflective layer
     85        modulated magnetic field
     85a       magnetic flux
     85b       magnetic flux
    150        coupling section
    201        decision step
    202        reproduction step
    203        reproduction copy step
    204        reproduction dedicated step
    205        recording copy step
    206        recording step
    207        copy step
    210        demagnetizing area
    210a       demagnetizing area
    210b       demagnetizing area
    301        shutter
    302        head hole
    303        liner hole
    304        liner
    305        liner supporting section
    305a       movable section
    305b       sub-liner supporting section
    305c       liner elevating section
    307        channel
    307a       liner driving channel
    310        liner pin
    311        liner pin guide
    312        pin driving lever
    313        recognition hole
    314        protective pin
    315        liner driving section
    316        pin shaft
    317        spring
    318        coupling portion
    319        pin shutter
    320        optical address
    321a       center
    321b       center
    321c       center
    322        optical data train
    323        address
    324        data
    325        guard band
    326        track group
    327        block
    328        track data
    328        synchronizing signal
    329        address
    330        parity
    331        data
    333        separation circuit
    334        modulation circuit
    335        disk circuit angle detecting section
    336        eccentricity correction memory
    337        signal-free area
    338        traverse control section
    339        table showing correspondence between optical
               address and magnetic address
    340        head amplifier
    341        demodulator
    342        error check section
    343        data separation section
    344        AND circuit
    345        recording data
    346        light-free address area
    347        optical address area
    348        magnetic TOC area
    349        track locus
    350        head reproduction section
    351        memory data
    352        coating material barrel
    353        coating material transfer roll
    354        intaglio drum
    355        etching section
    356        scriber
    357        soft transfer roll
    358        coating section
    360        magnetic shield
    361        resin section
    362        random magnetic field generator
    363        traverse shaft
    363b       magnetic head traverse shaft
    364        positional reference section
    365        disk lock section
    366        traverse coupling section
    367        traverse gear
    367c       magnetic head traverse gear
    368        reference table
    369        synchronizing section
    370        recording format
    371        track number section
    372        data section
    373        CRC section
    374        gap portion
    375        guide section for coupling section
    376        disk cleaning section
    377        magnetic head cleaning section
    378        noise canceller
    380        coupling section for disk cleaning section
    381        magnetic sensor
    382        optical reduction clock signal
    383        magnetic lock signal
    384        magnetic recording signal
    385        decision window time
    386        opdcal sensor
    387        optical mark
    387a       bar code
    388        light-transmitting section
    389        upper cover
    390        cassette cover
    391        magnetic plane shutter
    392        shutter coupling section
    393        cassette cover rotary shaft
    394        insertion opening
    395        tape
    396        label section
    397        buzzer
    398        magnetic recording area
    399        screen printer
    400        bar code printer
    401        high Hc section
    402        magnetic section
    402a       space section
    403        magnetic section
    404        key managing table
    405        step of flow chart
    406        key releasing decoder
    407        voice extension block
    408        personal computer
    409        hard disk
    410        install step
    411        application
    412        OS
    413        BIOS
    414        drive
    415        interface
    416        step of flow chart
    321        optical file
    422        magnetic file
    436        network BIOS
    437        LAN network
    447        step of flow chart
    447a       step of flow chart
    448        corrected data
    449        display
    450        key pad
    451        error correction step
    452        parity
    453        C1 parity
    454        C2 parity
    455        Index
    456        sub-code synchronism detecting section
    457        index detecting section
    458        divider
    459        magnetic synchronizing signal detecting section
    460        shortest/longest pulse detecting section
    461        pseudo optical synchronizing signal generating
               section
    462        pseudo magnetic synchronizing signal generating
               section
    463        optical synchronizing signal detector
    464        divider/multiplier
    465        change-over switch
    466        waveform shaping section
    467        clock reproducing section
    468        medium identifier
    469        optical address information
    470        data
    514        spring
    514a       head elevation coupling means
    514a       head elevation inhibiting means
    514c       optical head travelling area
    516        loading motor
    517        loading gear
    518        tray moving gear
    519        head elevator
    520        tray
    521        opening and closing shaft for upper cover
    522        menu image plane selection number table
    523        playback control information
    524        step of flow chart
    525        list ID offset table
    526        optical search information
    527        magnetic track search information



    528        master data
    529        mastering device
    530        data arrangement
    531        Zone
    532        physical arrangement (configuration) table (first
               physical feature information)
    533        illegal disk check circuit
    534        cipher decoder
    535        check circuit
    536        output/operation stopping means
    537        cipher encoder
    538        cipher signal
    539        physical position
    540        magnetizing device
    541        magnetizing device
    542        magnetizing device
    543        magnetizing current generator
    544        current direction switching device
    545a       coil
    546        ID number generator
    547        mixer
    548        separation key
    549        separator
    550        ID number
    551        step of flow chart
    552        physical arrangement signal
    553        angular position detecting section
    554        tracking amount detecting section
    555        pit depth detecting section
    556        measured disk physical arrangement table
    557        disk center
    558        rotational center of disk
    559        eccentric portion
    560        pit
    561        duplicate pit
    562        pulse signal
    563        duplicate preventing signal
    564        tracking modulation signal generating section
    565        copy preventing (protection) signal generating
               section
    566        optical output modulation signal generating section
    567        optical output modulating section
    568        pulse duration modulating section
    569        pulse duration adjusting section
    570        output address information section
    571        time base (axis) changing section
    572        original record
    573        photosensitive layer
    574        photosensitive section
    575        metallic original record
    576        formed disk
    577        second photosensitive section
    578        communication interface section
    579        external cipher decoder
    580        pit group
    581        reproduced waveform
    582        random extractor
    583        random number generating section
    565        image plane
    566        step (flow chart of step virtual file)
    567        window
    568        holder
    569        file
    570        CD-ROM icon
    571        CD-ROM-RAM icon
    572        HDD
    573        invisible file
    574        invisible folder
    575        display
    576        stereo-capacity display
    577        virtual capacity display
    578        password input section
    579        file name input section
    584        low-reflection section
    585        reference low-reflection section
    586        low-reflection light quantity detecting section
    587        light quantity level comparator
    588        light quantity reference value
    589        HPF
    590        waveform shaping circuit
    590a       AGC
    591        demodulating section
    592        EFM
    593        physical address output section
    594        address output section
    595        synchronizing signal output section
    596        low-reflection section address .multidot. clock number
               position signal output section
    597        n-1 address output section
    598        clock counter
    599        low-reflection section start/end position detecting
               section
    600        low-reflection section position detecting section
    601        low-reflection section angular position signal
               output section
    602        low-reflection section angular position detecting
               section
    603        n-1 address signal
    604        synchronizing signal
    605        low-reflection section start point
    606        low-reflection section end point
    607        time-delay correcting section
    608        reference delay time TD measuring section
    609        low-reflection section .multidot. address table
    610        vapor deposition preventing section
    611        protective layer
    612        ink
    613        light shielding section
    614        adhesive section
    615        first mask
    616        second mask
    617        printing section
    618        CP optical mark section
    620        bar code
    621        bar code demodulating section
    622        character pattern
    623        heating section
    624        heating head
    625        film
    626        disk physical ID
    627        stamper physical ID
    628        disk managing ID
    629        master cipher
    630        written layer
    631        error sign-address table
    632        CP error sign
    633        physical ID output section
    634        error sign list
    635        standard sign
    635        CPEFM conversion table
    637        original data
    638        decode data
    639        CP special sign
    640        CP special sign detecting section
    641        CP special sign address output section
    642        CP special sign-address table
    643        laser trimming device
    644        laser beam deflecting device
    645        off-track switching circuit
    646        track servo polarity inverting section
    647        off-track signal reproducing section
    648        optical sensor
    649        optical beam spot
    650        inphase reproduction signal
    651        negative-phase reproduction signal
    652        inphase reproduction signal
    653        inphase signal block
    654        frame sync signal
    655        foreign substance
    656        pulse duration modulation signal demodulating
               section
    657        reproduction output detecting section
    658        reproduction output reference value
    659        reproduction output lowering section
    660        offset voltage detecting section
    661        switching section
    662        2 demodulators
    663        2 personal computers
    664        network
    665        CPU
    666        step (install program)
    667        step (legal disk check routine)
    668        step (machine ID check making-out recording
               routine)
    669        step (legal cipher decoder check routine)
    670        step (routine for stepping usc of illegal copy soft)
    671        step (program executing routine)
    672        step (routine for stopping same ID number soft)
    673        step (program movement detecting step)
    674        step (machine ID check step)
    675        step (cipher decoder check routine)
    676        personal computer
    677        CD-ROM layer
    678        virtual ROM layer
    679        write-once layer
    680        recording layer
    700        original record
    701        recording layer
    703        physical feature information measuring section
    704        physical feature information transmitting section
    705        physical feature information receiving section
    706        plain text information output section
    707        first recording
    708        second recording area
    709        first recording line
    710        second recording line
    711        step (orginal record flow chart)
    712        step (reproduction flow chart)
    713        step (stopping routine)
    714        plain text information output section
    715        plain text data checking section
    716        plain text data coincidence detecting section
    717        program executing stopping section
    718        sub-cipher decoder
    719        RAM section
    720        sub-cipher decode data
    721        data output section for conversion into plain text
    722        program/reproduction operation stopping section
    723        recording signal output section
    724        CPU
    739        pit number
    740        first low-reflection section
    741        high-reflection section
    742        optical recording signal area
    743        first physical feature information detecting means
    744        second recording means
    745        reproduction means
    746        first offset voltage
    747        inphase/negative-phase signal detecting section
    748        inphase/negative-phase signal position detecting
               section
    749        frame synchronizing signal detecting section
    750        ID number output section
    751        second low-reflection section
    752        TOC area
    753        second low-reflection section interval
    ______________________________________