초록 ▼

A disc or like article (10, 115, 119) rotatable by drive means, such as a compact disc for use with a computer, includes indication means (12, 110, 120) which, when the disc is rotated at or above a predetermined angular velocity, provide an indication that rotation has occurred, which indication ca

A disc or like article (10, 115, 119) rotatable by drive means, such as a compact disc for use with a computer, includes indication means (12, 110, 120) which, when the disc is rotated at or above a predetermined angular velocity, provide an indication that rotation has occurred, which indication can be important if the disc contains confidential information. The indication device can be a tube formed with two enclosures separated by a breakable membrane (15, 16, 112, 122), a colored liquid/gel (17, 111 121) being in one enclosure and passing into the second enclosure, by breaking the membrane, when the disc is spun, thereby providing a visual indication thereafter of the spinning having occurred The invention also relates to such an indication means, per se, for after-fitting to a disc recorded on by spinning, and to a method of producing a disc with said indication means.

대표청구항 ▼

The invention claimed is: 1. A readable disc, in use rotatable by drive means, having indication means or indication producing means that provide an indication that rotation has occurred when the disc in use is first rotated at or above a predetermined angular velocity characterized in that the ind

The invention claimed is: 1. A readable disc, in use rotatable by drive means, having indication means or indication producing means that provide an indication that rotation has occurred when the disc in use is first rotated at or above a predetermined angular velocity characterized in that the indication means or the indication producing means provide said indication that rotation has occurred without affecting reading of the disc during said first or any subsequent rotation of the disc. 2. A disc as claimed in claim 1, comprising a first enclosure, indication means or indication producing means in said first enclosure, and a second enclosure, said indication means or indication producing means being retained in the first enclosure until the disc is rotated, in use, at or above said predetermined angular velocity, whereupon there is passage of at least some of the indication means or indication producing means into the second enclosure and a resultant indication that rotation of the disc has occurred. 3. A disc as claimed in claim 2, wherein the resultant indication is visual. 4. A disc as claimed in claim 3, wherein said resultant indication can be viewed exteriorly of the disc, in use. 5. A disc as claimed in claim 2, wherein the first enclosure is separated from the second enclosure by breakable membrane means. 6. A disc as claimed in claim 2, wherein the indication means or indication producing means is a fluid. 7. A disc as claimed in claim 6, wherein the indication means or the indication producing means is a liquid. 8. A disc as claimed in claim 7, wherein the liquid is coloured. 9. A disc as claimed in claim 7, wherein said liquid in said first enclosure is clear, and said second enclosure contains further clear liquid, said liquids in said first and second enclosure respectively mixing upon said rotation of the disc, in use, at or above said predetermined angular velocity to provide a coloured visual indication of rotation having occurred. 10. A disc as claimed in claim 7, wherein the liquid is held in said first enclosure by surface tension at an outlet opening therefrom. 11. A disc as claimed in claim 1, wherein said indication means or said indication producing means is in the form of a tube having at least part thereof transparent. 12. A disc as claimed in claim 11, wherein the tube is circular in plan. 13. A disc as claimed in claim 12, wherein the circular tube is wholly transparent. 14. A disc as claimed in claim 11, wherein the tube comprises a circular hub from which at least one radial arm extends. 15. A disc as claimed in claim 14, wherein the hub and the at least one radial arm respectively constitute first and second enclosures, the first enclosure containing indication means or indication producing means. 16. A disc as claimed in claim 11, wherein the tube is straight. 17. A disc as claimed in claim 16, wherein the tube is flat. 18. A disc as claimed in claim 16, wherein the tube is wholly transparent. 19. A disc as claimed in claim 16, wherein the indication means or indication producing means is a gel. 20. A disc as claimed in claim 19, wherein the gel is held in said tube or a first enclosure of said tube by a membrane formed by the surface tension of the gel's viscosity. 21. A disc as claimed in claim 19, wherein the gel is arranged so that, in use, upon rotation of said disc it transfers bodily into said tube or a second enclosure of said tube. 22. A disc as claimed in claim 1, wherein the indication means or indication producing means is held in a first enclosure which is separated from a second enclosure, into which at least part of the indication means or indication producing means moves, in use, upon said rotation, by barrier means. 23. A disc as claimed in claim 22, wherein the baffler means are breakable films/sheets. 24. A disc as claimed in claim 1, wherein, in use, upon said rotation, the indication producing means produces a frictionally generated electrical charge which is utilized to provide said indication. 25. A disc as claimed in claim 24, wherein said indication is a conductant display. 26. A disc as claimed in claim 1, wherein, in use, upon said rotation, the indication producing means produces frictionally generated heat which is utilized to provide said indication. 27. A disc as claimed in claim 1, in which said indication that rotation has occurred is audible. 28. A disc as claimed in claim 1, in which said indication that rotation has occurred is tactile. 29. A disc as claimed in claim 1, in which said indication means or indication producing means is in the form of thin plastics material sheeting. 30. A disc as claimed in claim 1, including/incorporating photochromic material. 31. A disc as claimed in claim 30, wherein the indication means or indication producing means contains photochromic material. 32. A disc as claimed in claim 31, wherein the photochromic material is mixed with a gel. 33. A disc as claimed in claim 31, wherein the photochromic material changes its state, in use, when exposed to ultraviolet light. 34. A disc as claimed in claim 1, including a thin plate/disc on a screw-type pivot, which, in use, upon rotation of the disc, travels along the pivot to jam in a position which provides said indication. 35. A disc as claimed in claim 34, wherein said plate/disc is suspended in a suspension medium. 36. A disc as claimed in claim 34, wherein in said jammed position, in use, said plate/disc has smeared indication means to a surface of a case of the indication means or indication producing means. 37. A disc as claimed in claim 1, comprising a liquid crystal display which is activated, in use, by rotation of said disc. 38. A disc as claimed in claim 37, wherein the activation is by heat or electricity generated by the rotation of said disc, in use. 39. A disc as claimed in claim 37, wherein the activation is by laser light from a reader of the disc. 40. A disc as claimed in claim 12, wherein the tube is secured in a central circular opening through the disc. 41. A disc as claimed in claim 40, wherein the indication means or indication producing means is embedded in the body of the disc. 42. A disc as claimed in claim 41, wherein the indication means or indication producing means is embedded around a central hole of the disc. 43. A disc as claimed in claim 1, wherein the indication means or indication producing means is sandwiched between two layers of the disc. 44. A disc as claimed in claim 1, having at its periphery indication producing means which, when the disc is rotated, in use, produce a frictionally generated electrical charge which is utilized to provide said indication. 45. A disc as claimed in claim 44, wherein a counterbalance is provided to said indication device disc, to balance the disc upon rotation, in use. 46. A disc as claimed in claim 1, having a frame secured to one side thereof and carrying a pair of said indication means or indication producing means. 47. A disc as claimed in claim 46, wherein the frame is adhesively secured to the disc and the indication means or indication producing means are adhesively secured to the frame. 48. A disc as claimed in claim 46, wherein the frame has a central circular portion received in a central hole of the disc and at least two arms extending radially from said central portion, said arms respectively carrying said indication means in the form of tubes. 49. A disc claimed in claim 48, wherein the frame is formed of a thin plastics material sheet. 50. A disc as claimed in claim 1, wherein the indication means or indication producing means is disposed continuously around the outer periphery of the disc. 51. A disc as claimed in claim 1, which has photochromic material on a surface thereof. 52. A disc as claimed in claim 51, wherein the photochromic material is applied to the disc surface under a protective lacquer coating. 53. A disc as claimed in claim 52, wherein a change of state of the photochromic material, in use, renders wording and/or a logo visible. 54. A disc as claimed in claim 1, in the form of a CD for use with a computer having both a reading and writing ability.