Information recording media, optical disc and playback system
    1.
    发明公开
    Information recording media, optical disc and playback system 失效
    Informationsaufzeichnungsträger,optische Platten und Wiedergabesystem。

    公开(公告)号:EP0643391A1

    公开(公告)日:1995-03-15

    申请号:EP94113942.0

    申请日:1994-09-06

    申请人: HITACHI, LTD.

    摘要: A CD-ROM (4 in Fig. 1) is provided with an area for forming a character/graphic pattern (14). The character/graphic pattern (14) is formed in such a way that data, which generate on the CD-ROM (4) two sorts of pit patterns having average reflectances different from each other to a perceptible extent, are respectively recorded inside and outside the character/graphic pattern (14). Unless an illegal copy disc is produced by duplicating the legal original disc of the CD-ROM (4) at a very high precision, the character/graphic pattern of the copy disc is invisibly deformed by the discrepancy between the arrangements of the pit patterns of the copy disc and the original disc (4).

    摘要翻译: CD-ROM(图1中的4)设置有用于形成字符/图形(14)的区域。 字符/图形(14)形成为使得在CD-ROM(4)上生成具有彼此不同的平均反射度的两种凹坑图案的数据到可察觉的程度,分别被记录在内部和外部 字符/图形(14)。 除非通过以非常高的精度复制CD-ROM(4)的合法原始光盘来产生非法复制光盘,否则复制光盘的字符/图形将由于凹坑图案的布置之间的差异而不可见地变形 复印光盘和原始光盘(4)。