FINGERPRINT ANALYSIS DEVICE

• US 3,699,519 A
• Filed: 04/30/1971
• Issued: 10/17/1972
• Est. Priority Date: 04/30/1971
• Status: Expired due to Term

• Current Assignee: De la Rue Printrak Incorporated
• Original Assignee: Thomas De La Rue and Company Limited
• Inventors: Campbell, Mark E.
• Primary Examiner(s): Robinson, Thomas A.
• Application Number:
  US05/139,109
• Time in Patent Office: 536 Days
• Field of Search: 340/146.3E 235/61.11E
• US Class Current: 382/125
• CPC Class Codes: G06V 10/10 Image acquisition document image scanning and transmission H04N1/00; control of digital cameras H04N23/60
• CPC Class Codes: G06V 10/20 Image preprocessing
• CPC Class Codes: G06V 10/28 Quantising the image, e.g. histogram thresholding for discrimination between background and foreground patterns
• CPC Class Codes: G06V 10/40 Extraction of image or video features
• CPC Class Codes: G06V 30/144 using a slot moved over the image; using discrete sensing elements at predetermined points; using automatic curve following means
• CPC Class Codes: G06V 40/1324 by using geometrical optics, e.g. using prisms G06V40/1312 takes precedence
• CPC Class Codes: G07C 9/37 using biometric data, e.g. fingerprints, iris scans or voice recognition

Abstract

A fingerprint is observed, a small portion at a time, using a flying spot scanner, whose spot travels along a predetermined path at each position to provide an electrical analog signal indicative of the nature of the fingerprint at each position. The analog signal is converted into digital form and temporarily stored in a memory having a plurality of storage elements. The signal stored in the memory is constantly circulated through each of the storage elements to provide for detection of minutiae (i.e. ridge endings, bifurcations, etc.) regardless of their angular orientation. Detecting the occurrence of specified minutia is achieved by sensing the states of selected ones of the storage elements. A method is provided to utilize a finger from which the fingerprint is directly analyzed. Other means are provided to enable the fingerprint pattern to be observed directly and to make a copy of the fingerprint photographically and a combination of optical-electronic and electrostatic methods.

Claims

1. Apparatus for determining the characteristics of a fingerprint pattern, comprising in combination:

first means with said fingerprint pattern imposable thereon, said fingerprint pattern constituting the ridges and valleys of a real finger, and means embodied in the first means for sensing the presence of the real finger so as to preclude substitution of simulated fingerprint overlay on the real finger;

a cathode ray spot scanner;

second means in optical relationship with respect to the first means for directing a light beam from the spot scanner on said first means and for scanning said first means and said pattern;

third means optically coupled to said second means for edgeilluminating said first means thereby causing illumination of said ridges and interference with diffused reflection of light therefrom thereby accentuating the ridges of the print from the finger by virtue of the edge illumination, and in the absence of said finger disabling any substantial amount of light originating from the third means causing said diffused reflection;

fourth means for receiving light in accordance with modulation of the light beam by said pattern;

means for sequentially positioning the beam of said cathode ray spot scanner at coordinate locations along rectilinear axes including means for sequentially scanning the pattern at each of the coordinate locations with a plurality of successive polar scans having polar radii of different magnitudes for scanning a plurality of portions of each of the coordinate locations;

means for generating digital signals at successive points of each of said plurality of successive polar scans, said digital signals indicating the contrast at each point of the polar scan pattern at each of the coordinate locations; and

means for registering the digital signals, generated by each of said plurality of polar scans, for transfer thereof externally to said apparatus.

2. The invention as stated in claim 1, including:

means for comparing the stored digital signals from each corresponding point of the polar scans for detecting predetermined relationships between the digital signals including means for indicating the detection of said predetermined relationship.

3. The invention as stated in claim 1, including:

counter means for passing sequentially through a plurality of counts in synchronization with the comparison of said digital signals; and

means responsive to the detection of a predetermined relationship between the positions of said polar scans and the count of said counter means for indicating the angular orientation of detected pattern relative to a predetermined axis.

4. The invention as stated in claim 1, wherein:

sAid plurality of polar scans comprise three concentric polar scans and said means for storing comprises three shift registers including means for shifting the contents of the registers into the storing means for comparison.

5. The invention as stated in claim 4, including:

means responsive to the count of said counter means for sequentially connecting the registers to the means for generating whereby digital signals for each polar scan can be stored, and means simultaneously responsive to said count for controlling the radius of said polar scan including means for decreasing the radius of the scan after each scan until three polar scans have been completed; and

means responsive to the count in said counter means for moving said scanner to a subsequent coordinate point after the polar scans have been completed.

6. The invention as stated in 1, including:

fifth means electrically coupled to the cathode ray spot scanner for providing video control of the received fingerprint pattern; and

sixth means connected to the fifth means for displaying the received fingerprint pattern.

7. Apparatus for determining the characteristics of a fingerprint pattern, comprising in combination:

first means with said fingerprint pattern imposable thereon, said fingerprint pattern constituting the ridges and valleys of a real finger;

a cathode ray spot scanner;

second means in optical relationship with respect to the first means for directing a light beam from the spot scanner on said first means and for scanning said first means and said pattern;

third means optically coupled to said second means for edge-illuminating said first means thereby causing illumination of said ridges and interference with diffused reflection of light therefrom thereby accentuating the ridges of the print from the finger by virtue of the edge illumination, and in the absence of said finger disabling any substantial amount of light originating from the third means causing said diffused reflection;

fourth means for receiving light in accordance with modulation of the light beam by said pattern;

fifth means electrically coupled to the cathode ray spot scanner for providing video control of the received fingerprint pattern;

seventh means connected to the fifth means, said seventh means including video display means and a photographic plate for optically providing a photograph of said fingerprint pattern;

means for sequentially positioning the beam of said cathode ray spot scanner at coordinate locations along rectilinear axes including means for sequentially scanning the pattern at each of the coordinate locations with a plurality of successive polar scans having polar radii of different magnitudes for scanning a plurality of portions of each of the coordinate locations;

means for generating digital signals at successive points of each of said plurality of successive polar scans, said digital signals indicating the contrast at each point of the polar scan pattern at each of the coordinate locations; and

means for registering the digital signals, generated by each of said plurality of polar scans, for transfer thereof externally to said apparatus.

8. Apparatus for determining the characteristics of a fingerprint pattern, comprising in combination:

first means with said fingerprint pattern imposable thereon, said fingerprint pattern constituting the ridges and valleys of a real finger;

a cathode ray spot scanner;

second means in optical relationship with respect to the first means for directing a light beam from the spot scanner on said first means and for scanning said first means and said pattern;

third means optically coupled to said second means for edge-illuminating said first means thereby causing illumination of said ridges and interference with diffused reflection of light therefrom thereby accentuating the ridges of the print from the finger by virtue of the edge illumination, and in the absence of said finger disabling any Substantial amount of light originating from the third means causing said diffused reflection;

fourth means for receiving light in accordance with modulation of the light beam by said pattern;

fifth means electrically coupled to the cathode ray spot scanner for providing video control of the received fingerprint pattern;

eighth means connected to the fifth means, said eighth means including video display means having a cathode ray line-scan tube and a wired faceplate coupled to a fingerprint card for deposition of electrostatic charges upon said fingerprint card;

an electrostatic printer in receiving relationship to the fingerprint card having an electrostatic charge on said card for electrostatically producing the image of the fingerprint on said fingerprint card;

means for sequentially positioning the beam of said cathode ray spot scanner at coordinate locations along rectilinear axes including means for sequentially scanning the pattern at each of the coordinate locations with a plurality of successive polar scans having polar radii of different magnitudes for scanning a plurality of portions of each of the coordinate locations;

means for generating digital signals at successive points of each of said plurality of successive polar scans, said digital signals indicating the contrast at each point of the polar scan pattern at each of the coordinate locations; and

means for registering the digital signals, generated by each of said plurality of polar scans, for transfer thereof externally to said apparatus.

9. The invention as stated in claim 1, including:

means for providing recognition of the characteristics of said fingerprint pattern irrespective of the angular orientation of the fingerprint pattern.

10. The invention as stated in claim 1, including:

means connected to the means for sensing for providing an alarm whenever said substitution is sensed.