Personal identification method and personal identification device

Abstract

The invention offers a technique for personal identification which reduces the amount of computation required to match fingerprints, thereby shortening the processing time, while simultaneously improving the precision of the match. A press-type fingerprint sampler 1reads a 1 cm 2 area in the central portion of a fingerprint which has been pressed flat, and supplies fingerprint information representing a two-dimensional image of the fingerprint to a fingerprint match processing device 2. At the fingerprint match processing device 2, a minutiae extracting portion 21 b extracts eight types of minutiae (starting points, end points, bifurcation points, juncture points, dots, short lines, islands and scars) from the fingerprint information and writes these into the memory portion 22 to register the fingerprint. When matching the fingerprints, the fingerprints are similarly sampled by the press-type fingerprint sampler 1 to extract the minutiae, which are then supplied to a match computing portion 21 c. Additionally, a control computation processing portion 21 a reads the minutiae of the registered fingerprint and supplies them to a match computing portion 21 c. As a result, the match computing portion 21 c compares the minutiae of the sampled fingerprint and the minutiae of the registered fingerprint to determine whether or not they are the same.

What is claimed is:  
     
         1 . A personal identification method comprising steps of: 
 predetermining a standard range of a dermatoglyph containing a number of minutiae necessary to uniquely identify an individual; and    identifying the individual based on the dermatoglyph of said standard range.    
     
     
         2 . A personal identification method comprising steps of: 
 sequentially sampling dermatoglyphs from a plurality of locations on the body of an individual; and    identifying a subject as being the same as said individual if said subject presents the same dermatoglyphs from the same plurality of locations in the same order as they were sampled.    
     
     
         3 . A personal identification method comprising: 
 a first step of sampling a dermatoglyph over a predetermined standard range containing a number of minutiae necessary to uniquely identify an individual, and extracting and recording the minutiae from the sampled dermatoglyph;    a second step of sampling a dermatoglyph of an unidentified subject over said predetermined range and extracting the minutiae from the sampled dermatoglyph;    a third step of comparing the minutiae recorded in said first step and the minutiae extracted in said second step, and determining whether or not the dermatoglyph sampled in said first step and the dermatoglyph sampled in said second step are the same; and    identifying said unidentified subject as being the individual whose dermatoglyph was sampled in said first step if the dermatoglyph sampled in said first step and the dermatoglyph sampled in said second step are found to be the same.    
     
     
         4 . A personal identification method comprising: 
 a first step of sequentially sampling dermatoglyphs over a predetermined standard range containing a number of minutiae necessary to uniquely identify an individual from a plurality of locations on the individual, and extracting and recording the minutiae from the sampled dermatoglyphs;    repeating a second step of sampling a dermatoglyph over said predetermined range on an unidentified subject, and extracting minutiae from the sampled dermatoglyph, and a third step of comparing the minutiae recorded in said first step and the minutiae extracted in said second step, and determining whether or not the dermatoglyph sampled in said first step and the dermatoglyph sampled in said second step are the same, with respect to dermatoglyphs sequentially presented by said unidentified subject, with the minutiae of the dermatoglyphs sampled in said first step being used as the object of comparison in said third step in the same order as the order in which they are presented; and    identifying said unidentified subject as being the individual whose dermatoglyphs were sampled in said first step if the dermatoglyphs sequentially sampled in said first step and the dermatoglyphs sequentially sampled in said second step are all found to be the same.    
     
     
         5 . A personal identification device comprising: 
 sampling means for sampling a dermatoglyph over a predetermined standard range containing a number of minutiae necessary to uniquely identify an individual;    extracting means for extracting minutiae from the dermatoglyphs sampled by said sampling means;    memory means for recording minutiae information extracted by said extracting means for a registrant whose dermatoglyph has been previously sampled and registered by said sampling means; and    determining means for determining whether or not the dermatoglyph of said registrant is the same as the dermatoglyph of an unidentified subject by comparing minutiae information extracted by said extracting means from the dermatoglyph of the unidentified subject sampled by said sampling means and the minutiae information recorded by said memory means;    wherein said unidentified subject is identified as being the same individual as said registrant when the dermatoglyph of said registrant and the dermatoglyph of said unidentified subject are found to be the same by said determining means.    
     
     
         6 . A personal identification device comprising: 
 sampling means for sampling a dermatoglyph over a predetermined standard range containing a number of minutiae necessary to uniquely identify an individual;    extracting means for extracting minutiae from the dermatoglyphs sampled by said sampling means;    memory means for recording minutiae information of dermatoglyphs of a plurality of locations extracted by said extracting means from a registrant who has sequentially sampled and registered dermatoglyphs of said plurality of locations by said sampling means; and    determining means for comparing the minutiae information extracted by said extracting means from the dermatoglyphs of an unidentified subject sampled by said sampling means and minutiae information stored in said memory means, and determining whether or not the dermatoglyphs of said registrant are the same as the dermatoglyphs of said unidentified subject, wherein the minutiae information extracted from the dermatoglyphs sequentially presented by said unidentified subject are compared with minutiae information of the dermatoglyphs of said registrant sampled by said sampling means read out from said memory means in the same order as the dermatoglyphs are presented;    wherein said unidentified subject is identified as being the same individual as said registrant when the dermatoglyphs sequentially presented by said registrant and the dermatoglyphs sequentially presented by said unidentified subject are found to be the same by said determining means.    
     
     
         7 . A personal identification device in accordance with either  claim 5  or  6 , wherein said extracting means extracts starting points, end points, bifurcation points, juncture points, dots, short lines, islands and scars as minutiae.  
     
     
         8 . A personal identification device in accordance with either  claim 5  or  6 , wherein said standard range is a 1 cm 2  area in the central portion of a dermatoglyph.  
     
     
         9 . A personal identification device in accordance with either  claim 5  or  6 , wherein said sampling means comprises: 
 image taking means for acquiring an image of a dermatoglyph; and  
 fixing means for fixing the position of said standard range of the dermatoglyph in an image acquiring area of said image acquiring means.  
 
     
     
         10 . A personal identification device in accordance with  claim 9 , wherein said fixing means comprises a transparent member onto one side of which the dermatoglyph is pressed so as to be visible to said image taking means from the opposite side.  
     
     
         11 . A personal identification device in accordance with  claim 9 , wherein said fixing means comprises an ex-dermatoglyphic member for pulling the skin outside said standard range of the dermatoglyph, thereby exposing the flatly extended dermatoglyph more clearly to said image taking means.