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

• US 20040060978A1
• Filed: 09/30/2003
• Published: 04/01/2004
• Est. Priority Date: 12/07/1998
• Status: Active Grant

• Current Assignee: Hitachi, Ltd., Hitachi Research Institute (Hitachi, Ltd.)
• Original Assignee: Hitachi, Ltd., Hitachi Research Institute (Hitachi, Ltd.)
• Inventors: Okamoto, Chikashi, Usami, Mitsuo, Yagi, Hiroyuki, Tsuji, Kazutaka, Takaragi, Kazuo, Yasunobu, Chizuko, Tsunemi, Yasuhiro, Isobe, Asahiko
• Granted Patent: US 7,007,854 B2
• Time in Patent Office: Days
• US Class Current: 235/375
• CPC Class Codes: G06Q 20/042 characterized in that the payment protocol involves at least one cheque
• CPC Class Codes: G07D 7/003 using security elements using digital security elements G07D7/004
• CPC Class Codes: G07D 7/0047 using checkcodes, e.g. coded numbers derived from serial number and denomination
• CPC Class Codes: G07D 7/01 Testing electronic circuits therein
• CPC Class Codes: G07D 7/12 Visible light, infrared or ultraviolet radiation
• CPC Class Codes: G07D 7/2033 Matching unique patterns, i.e. patterns that are unique to each individual paper

Abstract

A method of checking sheets 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.

Claims

1. A method of checking sheets such as bonds, documents or the like as to forgery thereof, said sheet being provided with an electronic circuit chip from or in which information can be read out or written and having visible information, comprising the steps of:

encrypting the visible information of said sheet and storing the encrypted visible information in said electronic circuit chip, and

determining discriminatively authenticity of said sheet on the basis of the visible information of said sheet and the information stored in said electronic circuit chip.

2. A forgery checking method set forth in claim 1,

wherein said information stored is information resulting from encryption of physical or chemical information of sheet constituent elements which can discriminatively be identified externally of said sheet.

3. A forgery checking method set forth in claim 2,

wherein said information stored is information resulting from encryption of relative position information of a sheet constituent element relative to said electronic circuit chip.

4. A forgery checking method set forth in claim 3,

wherein said information stored includes digital signature information for said information.

5. A forgery checking method set forth in claim 1,

wherein said method comprises

determining previously a threshold value on the basis of elementary information stored in at least two electronic circuit chips incorporated in a single sheet,

making decision that said sheet is a forged one when difference is found in a greater number of said elementary information than said threshold value, and

making decision that said sheet is an authentic one when difference is found in a number of said elementary information which is equal to or smaller than said threshold value.

6. A forgery checking method set forth in claim 1,

wherein said method comprises

scanning said sheet in which said electronic circuit chip is mounted at a random position, and

encrypting the information obtained by said scanning or generating a digital signature and affixing said digital signature to said information or affixing said digital signature to the encrypted information for storage in said electronic circuit chip.

7. A forgery checking method set forth in claim 1,

wherein said method comprises

storing information inherent to said electronic circuit chip in said electronic circuit chip, and

storing said information to be stored in said electronic circuit chip in another storing means differing from said electronic circuit chip while establishing correspondence with the information inherent to said electronic circuit chip.

8. A sheet management system comprising:

means for receiving signals from sheets having respective electronic circuit chips incorporated therein, said electronic circuit chips including means for transmitting intermittently signals inherent to the relevant sheets, respectively, with every random transmission interruption periods and means for stopping the transmission in response to a stop command,

means for emitting a radio wave within a limited coverage while being moved along a direction in which said sheets are stacked, and

means for performing identification of the sheet upon reception of a signal from said sheet to thereby send a stop command valid only for said sheet, while waiting for a predetermined time unless the signal is received.