| 摘要 |
<p>PURPOSE:To establish a security system by a method wherein a pattern like insulation layer and a second insulation layer which conceals said insulation layer and is different in a dielectric constant are formed on a base material to form an area of a different electrostatic capacity two dimensionally. CONSTITUTION:A pattern like insulation layer 3 is formed on an aluminum layer side of a surface of a base material 1, and a surface protective layer 4 is further formed by applying polyethylene terephthalate so as to coat the whole base material 1. The surface protective layer 4 conceals the pattern like insulation layer 3. Then, the surface protective layer 4 side of a card 5 is corona charged with a charged part 6, and the charged card 5 is read with a surface charge measuring device. In that case, a pattern concealed under the surface protective layer 4 of polyethylene terephthalate can be read two dimensionally if scanned with a sensor, and a security system can be obtained by collating said data with a preliminarily settled data. Thereby the security system can be established.</p> |
