| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a photodiffraction sheet which can enhance a forgery-proof effect and has good designability. <P>SOLUTION: The photodiffraction sheet 800A comprises a photodiffraction structure forming layer 20A with a hologram or a diffraction grating pattern (checkers, a circle or radially arranged triangles), formed over the entire surface and a square pattern reflective layer 20B formed on the back. In addition, the effect (checkers, etc.) of the photodiffraction structure forming layer 20A is made to develop only in the range of the pattern reflective layer 20B (a square). Further, in the range of the outside of the pattern reflective layer 20B (a square), the effect (checkers) of the photodiffraction structure forming layer 20A is made not to develop. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
