Method of checking authenticity of sheet with built-in electronic circuit chip

摘要

A method of checking a sheet as to forgery thereof, the sheet being provided with an electronic circuit chip from or in which information can be read out or written and having visible information. The method includes a step of encrypting the visible information of the sheet and storing the encrypted visible information in the electronic circuit chip, and a step of determining discriminatively the authenticity of the sheet by comparing the visible information of the sheet with the information stored in the electronic circuit chip.