Device, fingerprint input device and machine-readable medium

Abstract

A device is not able to detect the forgery of a finger with high accuracy by the comparison of a reflected light image and a transmitted light image that are obtained from the same finger. A determination device is provided with an input means for receiving the reflected light image obtained by photographing a fingerprint of a finger with light reflected from the surface of the finger and the transmitted light image obtained by photographing the fingerprint of the finger with light transmitted through the finger, and a determination means for comparing the reflected light image and the transmitted light image, and outputting a real-forgery determination result of the fingerprint of the finger.

The invention claimed is: 
     
       1. A determination device comprising:
 an input circuit, which receives:   a reflected light image obtained by photographing a fingerprint of a finger by light reflected by a surface of the finger, and   a transmitted light image obtained by photographing the fingerprint of the finger by light transmitted through the finger; and   a determination circuit, which compares a minutia extracted from the reflected light image and a minutia extracted from the transmitted light image and outputs a real-forgery determination result of the fingerprint of the finger.   
     
     
       2. The determination device according to  claim 1 , wherein the determination unit extracts a first fingerprint pattern from the reflected light image and extracts a second fingerprint pattern from a first transmitted light image photographed using infrared light, and when the first fingerprint pattern and the second fingerprint pattern are similar, determines the fingerprint of the finger as a real one, and when the first fingerprint pattern and the second fingerprint pattern are not similar, determines the fingerprint of the finger as a forgery. 
     
     
       3. The determination device according to  claim 1 , wherein the determination unit extracts a minutia from each of the reflected light image and a second transmitted light image photographed using visible light, and determines the fingerprint of the finger as a real one when a difference in colors of the minutiae satisfies a predetermined condition, and determines the fingerprint of the finger as a forgery when the difference does not satisfy the predetermined condition. 
     
     
       4. A fingerprint input device comprising:
 the determination device according to  claim 3  and;   an imaging device which
 includes an optically transparent plate for placing the finger in a manner touching the plate, a first transmitted light source, placed around the plate, for radiating infrared light to the finger, a first image sensor, placed on an other side of the plate from the finger, apart from and facing the plate, a reflected light source, placed on the other side of the plate, apart from the plate in an outwardly oblique direction from a place where the finger is placed on the plate, for emitting visible light, 
 turns on one of the first transmitted light source and the reflected light source alternately and 
 outputs the first transmitted light image and the reflected light image formed on the first image sensor. 
   
     
     
       5. A fingerprint input device comprising:
 the determination device according to  claim 3  and;   an imaging device which includes an optically transparent plate for placing the finger in a manner touching the plate, a first transmitted light source, placed around the plate, for radiating infrared light to the finger, a first image sensor, placed on an other side of the plate from the finger, apart from and facing the plate, a reflected light source, placed on the other side of the plate, apart from the plate in an outwardly oblique direction from a place where the finger is placed on the plate, for emitting visible light, a second image sensor placed on the other side of the plate, apart from the plate, in a position symmetric to the reflected light source about a line passing the first image sensor and orthogonal to the plate,   turns on one of the first transmitted light source and the reflected light source alternately and   outputs the first transmitted light image formed on the first image sensor and the reflected light image formed on the second image sensor.   
     
     
       6. The fingerprint input device according to  claim 5 , wherein the first image sensor is a color image sensor and
 the imaging device further includes a second transmitted light source, placed around the plate, for radiating visible light to the finger and turns on one of the first transmitted light source, the second transmitted light source and the reflected light source alternately, and outputs the first transmitted light image, the second transmitted light image and the reflected light image formed on the first image sensor.   
     
     
       7. A fingerprint input device comprising:
 an image device which:
 includes an optically transparent plate for placing the finger in a manner touching the plate, a second transmitted light source, placed around the plate, for radiating visible light to the finger, a first image sensor, placed on an other side of the plate from the finger, apart from and facing the plate, a reflected light source, placed on the other side of the plate, apart from the plate in an outwardly oblique direction from a place where the finger is placed on the plate, for emitting visible light; 
 turns on one of the second transmitted light source and the reflected light source alternately and 
 outputs a second transmitted light image and the reflected light image formed on the first image sensor; and 
   the determination device according to  claim 1  which extracts a minutia from each of the reflected light image and the second transmitted light image, and, when a difference in colors of the minutiae satisfies a predetermined condition, determines the fingerprint of the finger as a real one, and when the difference does not satisfy the predetermined condition, determines the fingerprint of the finger as a forgery.   
     
     
       8. A determination device comprising:
 a means for receiving a reflected light image obtained by photographing a fingerprint of a finger by light reflected by a surface of the finger and a transmitted light image obtained by photographing the fingerprint of the finger by light transmitted through the finger; and   a means for comparing a minutia extracted from the reflected light image and a minutia extracted from the transmitted light image and outputting a real-forgery determination result of the fingerprint of the finger.   
     
     
       9. A non-transient machine-readable medium which records a determination program causing a computer to carry out processing of receiving a reflected light image obtained by photographing a fingerprint of a finger by light reflected by a surface of the finger and a transmitted light image obtained by photographing the fingerprint of the finger by light transmitted through the finger, and outputting a real-forgery determination result of the fingerprint of the finger by comparing a minutia extracted from the reflected light image and a minutia extracted from the transmitted light image. 
     
     
       10. The non-transient machine-readable medium according to  claim 9  which records the determination program causing the computer to carry out processing of extracting a first fingerprint pattern from the reflected light image and a second fingerprint pattern from a first transmitted light image photographed using infrared light, and determining the fingerprint of the finger as a real one when the both are similar, and determining the fingerprint of the finger as a forgery when the both are not similar. 
     
     
       11. The non-transient machine-readable medium according to  claim 9  which records the determination program causing the computer to carry out processing of extracting a minutia from each of the reflected light image and a second transmitted light image photographed using visible light, and determining the fingerprint of the finger as a real one when a difference in colors of the minutiae satisfies a predetermined condition, and determining the fingerprint of the finger as a forgery when the difference does not satisfy the predetermined condition. 
     
     
       12. A determination method comprising: receiving a reflected light image obtained by photographing a fingerprint of a finger by light reflected by a surface of the finger and a transmitted light image obtained by photographing the fingerprint of the finger by light transmitted through the finger; comparing a minutia extracted from the reflected light image and a minutia extracted from the transmitted light image; and outputting a real-forgery determination result of the fingerprint of the finger. 
     
     
       13. The determination method according to  claim 12 , comprising the steps of: extracting a first fingerprint pattern from the reflected light image and a second fingerprint pattern from a first transmitted light image photographed using infrared light; and determining the fingerprint of the finger as a real one when the both are similar, and determining the fingerprint of the finger as a forgery when the both are not similar. 
     
     
       14. The determination method according to  claim 12 , comprising; extracting a minutia from each of the reflected light image and a second transmitted light image photographed using visible light; and determining the fingerprint of the finger as a real one when a difference in colors of the minutiae satisfies a predetermined condition, and determining the fingerprint of the finger as a forgery when the difference does not satisfy the predetermined condition. 
     
     
       15. A device comprising:
 an optically transparent plate comprising a top surface contactable by a finger;   a plurality of first transmitted light sources configured to radiate infrared light that passes through-the finger at a same side of the finger at which the finger contacts the optically transparent plate without the infrared light first passing through the optically transparent plate before reaching the finger, wherein the plurality of first transmitted light sources include one or more left light sources and one or more right light sources, the one or more left light sources positioned to a left side of the optically transparent plate and radiate the infrared light towards a left side of the finger, the one or more right light sources positioned to a right side of the optically transparent plate and radiate the infrared light towards a right side of the finger, and the optically transparent plate positioned in-between the one or more left light sources and the one or more right light sources;   a reflected light source configured to radiate white light that passes through the optically transparent plate and then radiates the finger at the same side of the finger at which the finger contacts the optically transparent plate;   a second transmitted light source configured to radiate white light that passes through a tip of the finger at the same side of the finger at which the finger contacts the optically transparent plate without the white light passing through the optically transparent plate before reaching the finger;   at least one memory configured to store instructions; and   at least one processor configured to execute the instructions to:
 acquire a reflected light image based on the white light from the reflected light source; 
 acquire a first transmitted light image based on the infrared light from the at least two first transmitted light sources; 
 acquire a second transmitted light image based on the white light from the second transmitted light source; 
 compare the first transmitted light image and the reflected light image, yielding a first comparison result; 
 compare the second transmitted light image and the reflected light image, yielding a second comparison result; and 
 output a real-forgery determination result of a fingerprint of the finger using the first and second comparison results.  
   
     
     
       16. The device according to  claim 15 , wherein the at least one processor is further configured to execute the instructions to extract a first fingerprint pattern from the reflected light image and extract a second fingerprint pattern from the first transmitted light image, and when the first fingerprint pattern and the second fingerprint pattern are similar, determines the fingerprint of the finger as a real fingerprint, and when the first fingerprint pattern and the second fingerprint pattern are not similar, determine the fingerprint of the finger as a forgery.  
     
     
       17. The device according to  claim 15 , wherein the at least one processor is further configured to execute the instructions to count a number of minutia features in a particular region of the reflected light image to obtain a first minutia feature count and count a number of minutia features in the particular region of the first transmitted light image to obtain a second minutia feature count, and determine the fingerprint of the finger as a real fingerprint when the first minutia feature count is not less than the second minutia feature count, and determine the fingerprint of the finger as a forgery when the first minutia feature count is smaller than the second minutia feature count.  
     
     
       18. The device according to  claim 15 , wherein the at least one processor is further configured to execute the instructions to extract a specific point from each of the reflected light image and the second transmitted light image, and determine the fingerprint of the finger as a real fingerprint when a difference in colors of the specific point satisfies a predetermined condition, and determine the fingerprint of the finger as a forgery when the difference does not satisfy the predetermined condition.