| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a hidden pattern which has a large effect of forgery prevention and is very difficult to discriminate with a viewing means and is difficult to copy and to provide a discriminating tool therefor. <P>SOLUTION: With respect to an optical diffraction structure including a pattern (hidden pattern) which is formed with a diffraction grating formed in a flat part of a substrate and is difficult to discriminate, and a pattern which can be discriminated, one of the pattern of which is difficult to discriminate and the pattern which can be discriminated is formed with a plurality of regularly arrayed dots when the other is formed with stripes being an aggregation of pairing bands. This invention includes the discriminating tool for the hidden pattern. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
