发明名称 |
ARTICOLO AUTENTICATO,IN FOGLIO,DOTATO DI UN DISPOSITIVO DI AUTENTICAZIONE,A RIFLESSIONE-DIFFRAZIONE |
摘要 |
An improved authenticating device comprises a substrate bonded to the sheet material, the substrate having a reflective diffractive structure formed as a relief pattern on a viewable surface thereof, and a transparent material covering the structure. Specified grating parameters of the diffractive structure, obtainable at low cost, result in peculiar, but easily discernable, optical color properties that cannot be copied by color copying machines. |
申请公布号 |
IT1200367(B) |
申请公布日期 |
1989.01.18 |
申请号 |
IT19820019720 |
申请日期 |
1982.02.18 |
申请人 |
RCA CORP. |
发明人 |
WEBSTER WILLIAM MERLE JR.;RUSSELL JOHN PATRICK |
分类号 |
G07D7/00;B42D15/10;B44F1/06;B44F1/12;G02B5/18;G06K7/00;G06K7/12;G06K19/06;G06K19/10;G06K19/16;G07D7/12 |
主分类号 |
G07D7/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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