BIOLOGICAL DETECTION DEVICE, FINGERPRINT AUTHENTICATION DEVICE, AND BIOLOGICAL DETECTION METHOD

• US 20070215558A1
• Filed: 07/11/2006
• Published: 09/20/2007
• Est. Priority Date: 03/17/2006
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Niinuma, Koichiro, Shinzaki, Takashi
• Granted Patent: US 7,907,754 B2
• Time in Patent Office: Days
• US Class Current: 210/767
• CPC Class Codes: G06V 40/1394 using acquisition arrangements
• CPC Class Codes: G06V 40/45 Detection of the body part being alive

Abstract

A further object of the present invention is to provide a biological detection device and the like capable of performing processing promptly. An input voltage with a predetermined frequency is output from an oscillating portion. By performing switching using an analog switch, the input voltage is output to an electrode via a first resistance portion. A first comparator detects an output voltage, compares the voltage with a first reference threshold stored in a storage portion, and outputs an output. Furthermore, by performing switching using the analog switch, an input voltage is output to the electrode via a second resistance portion. A second comparator detects an output voltage, compares the voltage with a second reference threshold, and outputs an output. A determination portion determines whether a test body is a living finger or a gummy finger in accordance with a combination of the values of the outputs.

Claims

1. A biological detection device, comprising:

an oscillating portion which oscillates an input voltage having a specific frequency;

a plurality of circuit portions each of which is connected to the oscillating portion;

an electrode portion which applies the input voltage to a test body;

a circuit switching portion which switches the plurality of circuit portions so as to allow the input voltage to be output to the electrode portion via any one of the circuit portions; and

a discriminating portion which discriminates whether the test body is a living body or not, according to an output voltage with respect to the input voltage applied to the test body.

2. The biological detection device according to claim 1, wherein the electrode portion has a plurality of electrode portions the number of which is same as the number of the plurality of circuit portions, each of the electrode portions is connected to each of the circuit portions, and the discriminating portion discriminates whether the test body is the living body or not, according to the output voltage with respect to the input voltage applied to the test body via each of the circuit portions and each of the electrode portions respectively.

3. The biological detection device according to claim 2, further comprising a circuit combination changing portion which changes the connection relation between each of the circuit portions and each of the electrode portions.

4. The biological detection device according to claim 3, further comprising a synchronous control portion which synchronizes combination changing of the connection relation performed by the circuit combination changing portion, and discrimination of the output voltage performed by the discriminating portion in response to the combination changing.

5. The biological detection device according to claim 1, further comprising a storage portion which stores a reference threshold, wherein the discriminating portion determines whether the test body is the living body or not by comparing the reference threshold from the storage portion with the output voltage.

6. The biological detection device according to claim 1, wherein the discriminating portion has a counterfeit determination portion which determines whether or not the test body is a counterfeit.

7. The biological detection device according to claim 6, wherein the counterfeit determination portion or the biological determination portion determine whether the test body is the living body or not on the basis of a change in amplitude of the output voltage.

8. The biological detection device according to claim 1, wherein the discriminating portion has a counterfeit determination portion which determines whether or not the test body is a counterfeit, and a biological determination portion which determines whether the test body is the living body or not.

9. The biological detection device according to claim 8, wherein the counterfeit determination portion or the biological determination portion determine whether the test body is the living body or not on the basis of a change in amplitude of the output voltage.

10. The biological detection device according to claim 1, wherein each of the circuit portions is comprised of a resistance.

11. A fingerprint authentication device, comprising:

a fingerprint sensor which captures an image of a fingerprint of a test body;

an oscillating portion which oscillates an input voltage having a specific frequency;

a plurality of circuit portions each of which is connected to the oscillating portion;

an electrode portion which applies the input voltage to the test body;

a circuit switching portion which switches the plurality of circuit portions so as to allow the input voltage to be output to the electrode portion via any one of the circuit portions; and

a discriminating portion which discriminates whether the test body is a living body or not, according to an output voltage with respect to the input voltage applied to the test body.

12. The fingerprint authentication device according to claim 11, wherein the electrode portion and the fingerprint sensor are integrated.

13. A fingerprint authentication device, comprising:

a fingerprint sensor which captures an image of a fingerprint of a test body;

a biological detection portion;

a fingerprint sensor finger placement time storage portion which stores finger placement time for the test body placed on the fingerprint sensor;

a biological-detection finger placement time storage portion which stores a biological-detection finger placement time for the test body placed on the biological detection portion; and

a time comparing portion which judges whether or not the test body is properly placed, on the basis of the finger placement on fingerprint sensor time and the biological-detection finger placement time which are stored respectively in the fingerprint sensor finger placement time storage portion and the biological-detection finger placement time storage portion,

wherein the biological detection portion comprises;

an oscillating portion which oscillates an input voltage having a specific frequency;

a plurality of circuit portions each of which is connected to the oscillating portion;

an electrode portion which applies the input voltage to the test body;

a circuit switching portion which switches the plurality of circuit portions so as to allow the input voltage to be output to the electrode portion via any one of the circuit portions; and

a discriminating portion which discriminates whether the test body is a living body or not, according to an output voltage with respect to the input voltage applied to the test body,

and the time comparing portion judges whether the test body is placed properly, when the difference between the finger placement on fingerprint sensor time and the biological-detection finger placement time is within a range of constant values.

14. A biological detection method, comprising the steps of:

oscillating an input voltage having a specific frequency from an oscillating portion;

outputting the input voltage an electrode portion via any one of a plurality of circuit portions; and

discriminating whether a test body is a living body or not, according to an output voltage with respect to the input voltage applied to the test body.