Method and a system for verifying authenticity safe against forgery

• US 4,218,674 A
• Filed: 04/20/1978
• Issued: 08/19/1980
• Est. Priority Date: 09/09/1975
• Status: Expired due to Term

• Current Assignee: DASY Inter SA
• Original Assignee: DASY Inter SA
• Inventors: Brosow, Jorgen, Furugard, Erik
• Primary Examiner(s): Yusko, Donald J.
• Application Number:
  US05/898,149
• Time in Patent Office: 852 Days
• Field of Search: 340/149 A, 235/493, 235/487, 235/380
• US Class Current: 340/5.86
• CPC Class Codes: B42D 2033/16 Magnetic or magnetisable material
• CPC Class Codes: B42D 2035/02 Nature of the markings
• CPC Class Codes: B42D 2035/12 Shape of the markings
• CPC Class Codes: B42D 2035/16 Bars or lines
• CPC Class Codes: B42D 2035/20 Optical effects
• CPC Class Codes: B42D 2035/34 Markings visible under particular conditions or containing coded information
• CPC Class Codes: B42D 25/00 Information-bearing cards or sheet-like structures characterised by identification or security features; Manufacture thereof printing processes to produce identification or security features B41M3/14
• CPC Class Codes: B42D 25/369 Magnetised or magnetisable materials
• CPC Class Codes: G06K 19/10 at least one kind of marking being used for authentication, e.g. of credit or identity cards verification of coded identity or credit cards in mechanisms actuated by them G07F7/12
• CPC Class Codes: G06K 7/0163 by means of additional timing marks on the record-carrier
• CPC Class Codes: G06V 20/80 Recognising image objects characterised by unique random patterns
• CPC Class Codes: G07D 7/004 using digital security elements, e.g. information coded on a magnetic thread or strip
• CPC Class Codes: G07D 7/0047 using checkcodes, e.g. coded numbers derived from serial number and denomination
• CPC Class Codes: G07D 7/04 Testing magnetic properties of the materials thereof, e.g. by detection of magnetic imprint G07D7/01 takes precedence
• CPC Class Codes: G07D 7/20 Testing patterns thereon G07D7/004, G07D7/005 take precedence
• CPC Class Codes: G07F 7/086 by passive credit-cards adapted therefor, e.g. constructive particularities to avoid counterfeiting, e.g. by inclusion of a physical or chemical security-layer for security documents G07D7/00; for the reading of record-carriers in general G06K7/00; for the design of coded credit-cards G06K19/10

Abstract

This invention relates to a method and system for verifying authenticity safe against forgery of an object releasing a function said object being of base material having random imperfections in or on the same, comprising measuring random imperfections in or on the base material of said object in a predetermined measuring track over the surface of said object of base material having random imperfections in or on the same by means of a detector for detecting said random imperfections, said random imperfections optionally being supplied to said base material, converting said measured random imperfections into pulses, supplying said pulses together with timing pulses to an AND gate, whereby only simultaneously arriving pulses are passed, supplying said passed pulses to a shift register shifting with said timing pulses to obtain a binary code, comparing said binary code with a previously stored binary code of the same object, whereby the function is released if said binary codes are identical; as well as a system for carrying out the method.

Claims

1. A system for verifying the authenticity safe against forgery of a document by comparison of binary output signals therefrom with binary output signals previously stored, said system comprising:

(1) a document having randomly dispersed fibers of a magnetic or magnetizable material embedded within at least part of the base material of said document in order to give said documents an imperfection pattern individual thereto, said fibers having magnetic properties different from said base material,

(2) means for detecting said fibers in a predetermined measuring track over the surface of said document,

(3) means to convert said detected random fibers into an asymetric analogous pulse train,

(4) discriminator means for separating such pulses from said pulse train which have amplitudes exceeding a predetermined threshold value from pulses having smaller amplitudes than said level,

(5) a converter for converting said first-mentioned pulses to a series of detected pulses,

(6) means for producing a measuring start and stop signal defining the active scanning time period,

(7) a timing means supplying timing pulses, said timing means being indicia on the surface of said document, and

(8) means to coordinate said series of detected pulses and said timing pulses to produce a series of binary output signals, whereby a comparison will develop the indentity of said document.

2. The system of claim 1, wherein said means for producing a measuring start and stop signal is a monostable flip-flop arranged to activate a first input of an AND gate, said converter is arranged to supply said series of detected pulses to a second input of said AND gate, said timing means is an oscillator arranged to supply timing pulses having a fixed repetition frequency to a third input of said AND gate, and wherein said gate is arranged to supply said coordinated pulses to a shift register upon coincidence of its three inputs.

3. The system of claim 1, comprising a monostable flip-flop arranged to supply said measuring start and stop signal to a first input of a first AND gate, means arranged to supply said timing pulses to a second input of said first AND gate, said first AND gate being arranged upon coincidence of its two inputs, to supply shift pulses to a shift register and timing pulses to a first input of a second AND gate, means for supplying said series of detected pulses to a second input of said second AND gate, and wherein said second AND gate is arranged, upon coincidence of its two inputs, to supply said series of coordinated pulses to said shift register.

4. A method of verifying the authenticity of documents having a base material provided with randomly dispersed fibers of a magnetic or magnetizable material embedded within at least part of said material in order to give each document an imperfection pattern individual thereto and said imperfections having magnetic properties different from said base material, said method comprising the steps of:

(a) scanning at least one predetermined measuring track over the surface of said document with a scanner capable of measuring said magnetic properties to produce an asymmetric analogous pulse train representative of the number, distribution and magnetic properties of the fibers present in said track,

(b) separating such pulses from said pulse train which have amplitudes exceeding a predetermined threshold value from pulses having smaller amplitudes than said value,

(c) converting said first-mentioned pulses to a series of detected pulses having equal amplitudes but unequal pulse lengths proportional to the energy contents of each corresponding first-mentioned pulse,

(d) producing a measuring signal defining the scanning time period,

(e) producing a timing pulse train having a fixed pulse repetition frequency, said timing pulse train being supplied by indicia on the surface of said document,

(f) coordinating said timing pulse train with said series of detected pulses during said scanning time period to produce a series of binary output signals comprising one pulse for each time coincidence of a timing pulse with at least part of a detected pulse, and

(g) comparing said binary output signals with a binary output signal previously registered by means of steps (a) to (f) for the actual document to be verified and stored in a central computer.

5. The method of claim 4, wherein the number of measurable fibers of a magnetic or magnetizable material in said track are at least twenty.

6. The method of claim 4 wherein, for the registration of said previously registered binary output signal, said document is scanned repeatedly along at least one track and wherein from scanning to scanning mutually opposite binary output signals are obtained in at least one of the code positions, the step of registering for such at least one code position an individual indication to disregard values obtained for this position during future comparisons of said previously registered output signal with said binary output signal obtained from said document being subject to scanning.