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Optical disk, optical disk recording and reproducing apparatus and copy preventive method for optical disks

  • US 4,879,704 A
  • Filed: 07/16/1987
  • Issued: 11/07/1989
  • Est. Priority Date: 07/21/1986
  • Status: Expired due to Term
First Claim
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1. An optical disk recording and reproducing apparatus for recording and reproducing data from an optical disk divided into a plurality of sectors each thereof being preliminarily formatted with an address with m and n each representing a given positive integer, said apparatus comprising:

  • means for only reproducing data from said optical disk sectors respectively designated by addresses B0 to Bn ; and

    means for recording and reproducing data from said optical disk sectors respectively designated by addresses A0 to Am,said sectors designated by said addresses B0 to Bn serving as record-protected sectors and being adapted for the reproduction of data only irrespective of said optical disk comprising a read only-type optical disk, a DRAW-type optical disk or an erasable optical disk,whereby data having at least part thereof recorded on said record protected sectors designated by said addresses B0 to Bn is protected from being recorded on the same address sectors of another recordable optical disk.

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