Copy protectable optical media device and methodology therefor

• US 5,815,484 A
• Filed: 12/24/1996
• Issued: 09/29/1998
• Est. Priority Date: 12/28/1995
• Status: Expired due to Term

• Current Assignee: HIDE & SEEK Technologies Incorporated, Janathan Kolber
• Original Assignee: HIDE & SEEK Technologies Incorporated
• Inventors: Smith, Jerry R., Lackritz, Hilary S., McLaughlin, Mark, Merry, J. Bradford
• Primary Examiner(s): Edun, Muhammad N.
• Application Number:
  US08/780,098
• Time in Patent Office: 644 Days
• Field of Search: 369/275.2, 369/275.1, 369/275.5, 369/84, 369/100, 369/13, 369/47, 369/58, 369/59
• US Class Current: 369/275.1
• CPC Class Codes: G11B 19/12 by sensing distinguishing features of or on records, e.g. diameter end mark
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: G11B 7/0037 with discs
• CPC Class Codes: G11B 7/252 of layers other than recording layers
• CPC Class Codes: G11B 7/2534 polycarbonates [PC]
• CPC Class Codes: G11B 7/254 of protective topcoat layers

Abstract

Data storage media for use with optical scanning machines are adapted to limit access to information stored thereon. Optical disks are used in an optical readout system of a computer to limit continual access to stored data by the optical readout system. A method is provided for limiting access to data stored in an optical media environment.

Claims

1. A method of limiting access to data stored on an optical medium, comprising the steps of:

(a) rotating an optical disk in a disk drive at a selected rotational speed, said optical disk including an area coincident with a substrate and a metallic layer encoded with information stored thereon as a plurality of readable data structures and said area also coincident with a reactive compound superimposed over at least said data structures of said area, said reactive compound intended to be operative in an ambient environment containing oxygen for reacting with the oxygen to change an optical transmission from said area in response to irradiation for an accumulated duration of time by light having a beam wavelength within a selected range; and

(b) directing an interrogating beam of light having a beam wavelength that is within the selected range toward at least a portion of said area and through said reactive compound for the accumulated duration of time.

2. The method of limiting access to data according to claim 1 wherein said interrogating beam is directed toward said area for a continuous interval of time that is sufficient to cause said change in optical transmission.

3. The method of limiting access to data according to claim 1 wherein said interrogating beam is directed toward said area for a plurality of discrete intervals of time, wherein each of said discrete intervals are spaced apart in time from one another, and wherein no single one of said intervals is sufficient to cause said change in optical transmission, but an accumulation of a length of time of said intervals is sufficient to cause said change.

4. The method of limiting access to data according to claim 1 wherein said beam wavelength is approximately 780 nanometers (nm).

5. The method limiting access to data according to claim 1 wherein said beam wavelength is approximately 650 nanometers (nm).

6. The method of limiting access to data according to claim 1 wherein said step of directing said interrogating beam toward said area is accomplished by selectively advancing said interrogating beam radially across an outermost surface of said optical disk until said interrogating beam interacts with said reactive compound for a plurality of discrete intervals of time sufficient to cause said change optical transmission.

7. A method of limiting access to data according to claim 1 wherein said beam intensity is approximately 1 milliwatt (mW) of power.

8. A method of limiting access to data according to claim 7 wherein said beam wavelength is approximately 780 nanometers (nm).

9. A method as claimed in claim 1, wherein said step of directing purposefully oxidizes said reactive compound.

10. A method as claimed in claim 1, wherein said reactive compound changes between an optically transparent state effective for reading the data structures stored coincidentally with said portion of said area, and an optically opaque state that inhibits reading the data structures stored coincidentally with said portion of said area.

11. An optical disk adapted for use in an optical readout system that includes a light source operative to produce an interrogating beam of light for reading data structures, comprising:

(a) a metallic layer encoded with information stored thereon as a plurality of data structures that are readable by an interrogating beam of light;

(b) a substrate disposed in a confronting relationship with said metallic layer;

(c) a film of a reactive compound superimposed over at least some of said data structures, said reactive compound selected to be of a type which is operative to change, in response to a predetermined stimulus applied to the reactive compound, between;

(i) an optically transparent state wherein a sufficient amount of said interrogating beam of light penetrating said reactive film compound reflects from the data structures encoded on said metallic layer so that said data structures can be read; and

(ii) an optically opaque state wherein there is an insufficient amount of said interrogating beam of light penetrating said reactive film compound for reading the data structures via reflections of said interrogating beam of light.

12. An optical disk according to claim 11 wherein said reactive compound is interposed between said metallic layer and said substrate.

13. An optical disk according to claim 12 wherein said metallic layer is contoured to include a sequence of pits and lands which define said plurality of data structures, said reactive compound superimposed over at least some of said pits and lands.

14. An optical disk according to claim 11 wherein said reactive compound is supported on an outer surface of said substrate and has a thickness in a range of approximately 0.14 to 0.6 microns.

15. An optical disk according to claim 11 wherein said predetermined stimulus is selected from a group consisting of visible light, infrared light, an ambient environment containing light and oxygen, and air.

16. An optical disk according to claim 15 wherein said predetermined stimulus is light and wherein said reactive compound includes a photoreactive material that changes its chemical composition when at least exposed to air.

17. An optical disk according to claim 16 wherein said reactive compound is selected from a spiropyran class of photochromic compounds.

18. An optical disk according to claim 17 wherein said reactive compound is 6-nitro-1'"'"'3'"'"'3'"'"'-trimethylspiro 2H-1-benzothiopyran-2,2'"'"'-indoline!.

19. An optical disk according to claim 18 wherein said reactive compound is operative to change to an optically darkened state in response to an interrogating beam wavelength of approximately 780 nanometers (nm) and thereafter return to an optically clear state in response to irradiation by a beam of light having a wavelength of approximately 337 nanometers (nm).

20. An optical disk according to claim 15 wherein said predetermined stimulus is an ambient environment containing light and oxygen and wherein said reactive compound has the chemical formula:

##STR7##

21. An optical disk according to claim 15 wherein said predetermined stimulus is an ambient environment containing light and oxygen and wherein said reactive compound has the chemical formula:

##STR8##

22. An optical disk according to claim 15 wherein said predetermined stimulus is air and wherein said reactive compound is operative after an accumulated duration of time to oxidize and change said state of the reactive compound.

23. An optical disk according to claim 22 wherein said reactive compound absorbs light having a wavelength within a predetermined range effective for facilitating a change between the transparent and opaque states of said reactive compound.

24. An optical disk according to claim 23 wherein said wavelength is approximately 780 nanometers (nm).

25. An optical disk according to claim 23 wherein said wavelength is approximately 650 nanometers (nm).

26. An optical disk according to claim 22 wherein said reactive compound is a chemically reduced form of a dye.

27. An optical disk according to claim 26 wherein said reactive compound is selected from a group of dyes consisting of methylene blue, brilliant cresyl blue, basic blue 3 and toluidine blue 0.

28. In an optical disk for use in an optical readout system wherein said optical disk includes a metallic layer encoded with information stored thereon as a plurality of data structures and a substrate, and wherein said optical readout system includes:

a disk drive operative to rotate the optical disk at a selected rotational speed, a light source operative to produce an interrogating beam of light at a selected beam wavelength and at a selected beam intensity and to direct said interrogating beam of light at the data structures, and a detector operative to collect a returned component of said interrogating beam and to produce an output signal in response thereto, an improvement comprising a film of a reactive compound superimposed over at least some of said data structures, said reactive compound operative to produce a change in its physical characteristics between;

(i) an optically transparent state wherein a sufficient amount of said interrogating beam of light penetrating said reactive compound reflects from at least some of the data structures encoded on said metallic layer so that said at least some of the data structures can be read; and

(ii) an optically opaque state wherein there is an insufficient amount of said interrogating beam of light penetrating said reactive compound for reading said at least some of the data structures via reflections of said interrogating beam of light;

wherein said change is in response to a predetermined environmental stimulus for affecting a readability of said at least some data structures by the interrogating beam of light.

29. The improvement of claim 28 wherein said reactive compound is responsive to irradiation by the interrogating beam for an accumulated duration of time to intentionally change a chemical characteristic of said reactive compound when said reactive compound changes between said states.

30. An article of manufacture adapted to be encoded with data and further adapted so that duplication of the data by an optical scanning machine may be prevented, comprising:

(a) a substrate fabricated from a selected material and having a substrate surface which contains the data; and

(b) a reactive compound coating at least a portion of said substrate surface, said reactive compound operative to change from an optically transparent state to an optically opaque state in response to irradiation for an accumulated duration of time by infrared light having desired characteristics, thereby to prevent light from the optical scanning machine from penetrating said reactive compound and to render the data undetectable by the optical scanning machine.

31. A method of limiting access to data stored on an optical disk having:

(a) a substrate, (b) a metallic layer encoded with information capable of being read by detecting optical reflections from said metallic layer; and

(c) a reactive layer through which the radiation passes prior to being reflected for reading the information, comprising;

exposing said reactive layer to a predetermined environmental stimulus for changing an optical characteristic of said reactive layer between the following states of (i) and (ii);

(i) an optically transparent state, wherein effective reading of the information is capable of being performed by detecting optical reflections of the radiation; and

(ii) an optically opaque state, wherein for at least a predetermined portion of said information, said optical reflections of said portion are sufficiently reduced so as to preclude reading of said information;

activating an optical disk reader for reading said information from said optical disk by detecting reflections of the radiation directed at said metallic layer;

reading said information when said reactive layer is in a transparent state;

failing to read said information when said reactive layer is in said opaque state.

32. A method as claimed in claim 31, wherein said optical disk reader is a read-only device.

33. A method as claimed in claim 31, wherein said step of exposing is performed during a reading of said information from said optical disk.

34. An optical disk adapted for use in an optical readout system that includes a light source operative to produce an interrogating beam of light for reading data structures, comprising:

(a) a metallic layer encoded with information stored thereon as a plurality of data structures that are readable by an interrogating beam of light;

(b) a substrate disposed in a confronting relationship with said metallic layer;

(c) a film of a reactive compound superimposed over at least some of said data structures, said reactive compound selected to be of a type which is operative to change physical characteristics in response to a selected stimulus thereby to affect readability of the data structures by said interrogating beam of light;

wherein said stimulus is light and wherein said reactive compound is a photoreactive material selected from a spiropyran class of photochromic compounds.

35. An optical disk according to claim 34, wherein said reactive compound is 6-nitro-1'"'"'3'"'"'3'"'"'-trimethylspiro.

36. An optical disk according to claim 35, wherein said reactive compound is operative to change to an optically darkened state in response to an interrogating beam wavelength of approximately 780 nanometers (nM) and thereafter return to an optically clear state in response to irradiation by a beam of light having a wavelength of approximately 337 nanometers (nM).

37. An optical disk adapted for use in an optical readout system that includes a light source operative to produce an interrogating beam of light for reading data structures, comprising:

(a) a metallic layer encoded with information stored thereon as a plurality of data structures that are readable by an interrogating beam of light;

(b) a substrate disposed in a confronting relationship with said metallic layer;

(c) a film of a reactive compound superimposed over at least some of said data structures, said reactive compound selected to be of a type which is operative to change physical characteristics in response to a selected stimulus thereby to affect readability of the data structures by said interrogating beam of light;

wherein said stimulus is an ambient environment containing light and oxygen and wherein said reactive compound has the chemical formula;

##STR9##

38. An optical disk adapted for use in an optical readout system that includes a light source operative to produce an interrogating beam of light for reading data structures, comprising:

(a) a metallic layer encoded with information stored thereon as a plurality of data structures that are readable by an interrogating beam of light;

(b) a substrate disposed in a confronting relationship with said metallic layer;

(c) a film of a reactive compound superimposed over at least some of said data structures, said reactive compound selected to be of a type which is operative to change physical characteristics in response to a selected stimulus thereby to affect readability of the data structures by said interrogating beam of light;

wherein said stimulus is an ambient environment containing light and oxygen and wherein said reactive compound has the chemical formula;

##STR10##