| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent confidential information from being leaked by enabling a recording medium to be detected by a gate type metal detector, thereby surely detecting the carrying-out of the recording medium. <P>SOLUTION: The gate type metal detector for receiving with a receiving coil an alternating current electromagnetic field generated in a gate path by a transmitting coil to detect metal on the basis of a change in an induced voltage is provided at a room entrance, and a recording medium managed in the room is provided integrally with a metal body so that the gate type metal detector can detect the recording medium. The recording medium is provided by proving a short coil 2 made of metal so as to surround an outer circumferential side face of a CD 1, providing a short coil on the top and bottom faces of an outer circumferential part of the CD 1 to connect both ends of the short coils, forming a two-turn coil, and pasting circular metallic foil concentrically on the surface of the CD 1. In addition, in a recording medium with a recording disk and a case formed integrally, such as an FD, a short coil may be provided in an inner face of the case. <P>COPYRIGHT: (C)2007,JPO&INPIT |
