| 摘要 |
<p>The system uses a lithium niobate crystal type transponder. It consists of a transmitter (10) for sending electromagnetic waves towards the transponder (14) carrying the lithium niobate crystal (16). The electromagnetic waves are converted into surface sound waves which are coded by means of a set of metal bars connected or not connected to a common bar so as to represent the identification code specific to the transponder. The waves are retransmitted in the form of electromagnetic waves to the receiver (12). By using a cement base containing an irregular distribution of impurities, it is possible to give the transponder a "signature" that cannot be reconstituted, which is used in the certification and authentication of works of art. <IMAGE></p> |
