| 摘要 |
<P>PROBLEM TO BE SOLVED: To reproduce additional information incrementally recorded on a reproduction-only optical disk medium without requiring a special reading function. <P>SOLUTION: At a stage in which disk substrates are manufactured in a large quantity using a stamper, a zone in which pits/lands are not formed is previously formed as an additional information recording area within a recording track formed by a recording data string of pits/lands. A metal alloy reflective film is applied on an information recording surface including such an additional information recording zone 10. After that, a part of the region of the metal alloy reflective film in the additional information recording zone 10 is removed or reduced to form a perforated mark 6, thereby recording additional information. This additional information is recorded onto a part of the region of the recording track in an information recording area (in which information is recorded by a recording data string of pits/lands and which includes a content area and a management area such as a lead-in area). The perforated mark 6 is formed as a mark from which a logical value similar to a pit can be obtained when being reproduced. <P>COPYRIGHT: (C)2008,JPO&INPIT |
