Biometric authentication device and method

• US 9,830,498 B2
• Filed: 12/21/2015
• Issued: 11/28/2017
• Est. Priority Date: 09/27/2012
• Status: Active Grant

• Current Assignee: TrueLight Corporation
• Original Assignee: TrueLight Corporation
• Inventors: Pan, Jin Shan, Chen, Chih Cheng, Chang Chien, Chia Ching
• Primary Examiner(s): Potts, Ryan P
• Application Number:
  US14/976,173
• Publication Number:
  US 20160104028A1
• Time in Patent Office: 708 Days
• Field of Search: None
• CPC Class Codes: G06V 40/12 Fingerprints or palmprints
• CPC Class Codes: G06V 40/1324 by using geometrical optics, e.g. using prisms G06V40/1312 takes precedence
• CPC Class Codes: G06V 40/1341 Sensing with light passing through the finger
• CPC Class Codes: G06V 40/1353 Extracting features related to minutiae or pores
• CPC Class Codes: G06V 40/1371 Matching features related to minutiae or pores
• CPC Class Codes: G06V 40/14 Vascular patterns
• CPC Class Codes: G06V 40/70 Multimodal biometrics, e.g. combining information from different biometric modalities

Abstract

A biometric authentication device uses IR-VCSELs as light sources for performing biometric authentication by providing clear images. A light guide module is introduced to minimize the size of the device. Moreover, the biometric authentication device uses a single image sensing module to gather a vein image and a fingerprint image into the same detection signal which is then analyzed and compared with the pre-stored vein feature data and fingerprint feature data.

Claims

1. A biometric authentication device, for verifying at least a biometric on a portion of a creature to be verified (PTBV), the PTBV comprising at least a portion of a first finger member and a second finger member of a finger, said biometric authentication device comprising:

a carrier base, having an upper opening for receiving at least the first finger member and the second finger member of the PTBV, which the upper opening further has a base plane and at least one lateral surface;

a position structure, located at the carrier base at a position respective to the upper opening, used to assist the PTBV to anchor at a predetermined position at the carrier base in the upper opening;

at least one light source unit, located at the at least one lateral surface of the carrier base respective to the upper opening;

in the case that the PTBV reaches the predetermined position, the at least one light source unit positioned laterally to the PTBV, and the at least one light source unit projects at least one lateral light onto the PTBV such that said lateral light penetrates both the first finger member and the second finger member of the PTBV to generate a fingerprint image and a vein image respectively corresponding to the first finger member and the second finger member of the PTBV;

a light guide module, located inside the carrier base at a position under the base plane respective to the upper opening; and

an image-sensing unit, located inside the carrier base to receive both the fingerprint image and the vein image and further to form thereby a corresponding detection signal readable to a computer;

both the fingerprint image and the vein image entering the carrier base through the base plane of the upper opening and projected onto the image-sensing unit via the light guide module;

wherein the fingerprint image is generated by having the lateral light penetrating the first finger member, while the vein image is generated by having the lateral light penetrating the second finger member;

wherein the light guide module is separated into a fingerprint-detecting area and a vein-detecting area;

the fingerprint image formed on the image-sensing unit through the fingerprint-detecting area of the light guide module, the vein image formed on the image-sensing unit through the fingerprint-detecting area of the light guide module;

wherein the first finger member contacts a top surface of the fingerprint-detecting area in order to generate the fingerprint image when the lateral light penetrates the first finger member and the second finger member is located above but does not contact another top surface of the vein-detecting area in order to generate the vein image when the lateral light penetrates the second finger member;

wherein, when the at least one lateral light penetrates the PTBV, the fingerprint image and the vein image are formed simultaneously on the image-sensing unit through the fingerprint-detecting area and the vein-detecting area of the light guide module, respectively, and then the image-sensing unit generates the detection signal readable to the computer and has messages of the fingerprint image and the vein image;

wherein the position structure is formed as a finger-anchoring structure located on the base plane and further includes a front window, a rear window and a position rib between the front window and the rear window;

while an inter-member valley between the first finger member and the second finger member falls onto the position rib, the first finger member is anchored in the front window and the second finger member is anchored in the rear window; and

the fingerprint-detecting area is respective to the front window and the vein-detecting area is respective to the rear window; and

wherein the light guide module has one single prism unit separated into the fingerprint-detecting area and the vein-detecting area;

the fingerprint-detecting area of the prism unit further includes the top surface, a bottom surface opposing to the top surface, an imaging surface connecting in-between the top surface and the bottom surface, and an anti-reflection surface opposing to the imaging surface, the top surface neighboring the front window of the position structure;

when the PTBV is anchored at the predetermined position in the upper opening, the first finger member of the finger contacting the top surface of the fingerprint-detecting area, the fingerprint image entering the fingerprint-detecting area of the prism unit via the top surface of the fingerprint-detecting area, the fingerprint image reflected at least once by the bottom surface of the fingerprint-detecting area and then leaving the prism unit through the imaging surface of the fingerprint-detecting area, an oblique angle of the imaging surface of the fingerprint-detecting area causing the leaving fingerprint image to form on the image-sensing unit, the anti-reflection surface reducing the reflection; and

the vein-detecting area of the prism unit further includes said another top surface, another bottom surface opposing to the another top surface, another imaging surface connecting in-between the another top surface and the another bottom surface, and a reflection surface opposing to the another imaging surface and forming an oblique angle with the another bottom surface;

said another top surface of the vein-detecting area neighboring the rear window of the position structure;

when the PTBV is anchored at the predetermined position in the upper opening, the second finger member of the finger being above said another top surface of the vein-detecting area without any contact in between, the vein image entering the vein-detecting area of the prism unit via said another top surface of the vein-detecting area, the vein image reflected at least once individually by the reflection surface, said another top surface and said another bottom surface of the vein-detecting area, and then leaving the prism unit through said another imaging surface of the vein-detecting area, the oblique angle of said another imaging surface of the vein-detecting area causing the leaving vein image to form on the image-sensing unit;

an imaging optical path of the vein image depending on a vertical height between said another top surface and said another bottom surface of the vein-detecting area and a reflection frequency of the vein image inside the vein-detecting area, in which the reflection frequency is determined by the oblique angle between the reflection surface and said another bottom surface of the vein-detecting area.

2. The biometric authentication device according to claim 1, wherein the at least one light source unit further includes a plurality of Infrared Vertical-cavity Surface-emitting Lasers (IR-VCSELs), and a vertical height h1 between a mean central point of the at least one light source unit at a perpendicular direction to the mean central point, and the base plane of the upper opening is no less than one half of a mean vertical thickness h2 of the PTBV.

3. The biometric authentication device according to claim 2, wherein the at least one lateral light projected by the at least one light source unit defines a virtual central projection line, a projection direction of the fingerprint image and the vein image downward into the carrier base defines a virtual vertical projection line, and an angle θ

between the virtual central projection line and the virtual vertical projection line is ranged between 30 and 150 degrees.

4. The biometric authentication device according to claim 1, wherein the light guide module further includes a mirror and a mirror base for mounting the mirror, the mirror forming the vein-detecting area.

5. The biometric authentication device according to claim 1, further including a light-shielding plate located at the position structure and a control module connecting electrically at least with the at least one light source unit and the image-sensing unit, the control module further including:

a detecting element for detecting whether or not the PTBV is in the upper opening;

a controller, connecting electrically the detecting element, for determining the at least one light source unit to project the at least one lateral light according to a detection of the detecting element; and

an image-processing unit, connecting electrically the image-sensing unit and the controller, for performing a pre-management and a feature-capturing management while receiving the detection signal from the image-sensing unit;

wherein the pre-management performs de-noise and image optimization processes upon the detection signal, and the feature-capturing management extracts fingerprint feature data from the fingerprint image and vein feature data from the vein image of the detection signal.

6. A biometric authentication method, for verifying at least a biometric on a portion of a creature to be verified (PTBV), the PTBV comprising at least a portion of a first finger member and a second finger member of a finger, said biometric authentication method comprising the steps of:

providing a biometric authentication device, the biometric authentication device comprising;

a carrier base, at least one light source unit, a light guide module, an image-sensing unit and a control module;

the carrier base receiving at least the first finger member and the second finger member of the PTBV, the at least one light source unit projecting at least one lateral light onto and also penetrating both the first finger member and the second finger member of the PTBV to generate a fingerprint image and a vein image respectively corresponding to the first finger member and the second finger member of the PTBV, the light guide module guiding the fingerprint image and the vein image toward the image-sensing unit, the image-sensing unit receiving the fingerprint image and the vein image and thereby generating a detection signal readable to a computer;

wherein generating the detection signal includes simultaneously generating messages of the fingerprint image and the vein image;

wherein the control module electrically connects at least with the at least one light source unit and the image-sensing unit;

arranging the PTBV to the biometric authentication device to generate the detection signal including the messages of the fingerprint image and the vein image;

the control module of the biometric authentication device receiving the detection signal and extracting therein fingerprint feature data from the fingerprint image and vein feature data from the vein image; and

applying an authentication unit to compare the fingerprint feature data and the vein feature data with pre-stored fingerprint feature data and vein feature data in a feature database to generate a comparison result;

wherein, the fingerprint image is generated by having the light penetrating the first finger member, while the vein image is generated by having the light penetrating the second finger member;

wherein the light guide module is separated into a fingerprint-detecting area and a vein-detecting area;

the fingerprint image formed on the image-sensing unit through the fingerprint-detecting area of the light guide module and the vein image formed on the image-sensing unit through the fingerprint-detecting area of the light guide module;

wherein the first finger member contacts a top surface of the fingerprint-detecting area to generate the fingerprint image when the light penetrates the first finger member and the second finger member is located above but does not contact another top surface of the vein-detecting area in order to generate the vein image when the light penetrates the second finger member;

wherein the carrier base has an upper opening that receives the first finger member and the second finger member of the PTBV, and the upper opening further has a base plane and at least one lateral surface;

the biometric authentication device further includes a position structure, the position structure located at the carrier base at a position respective to the upper opening assisting the PTBV to anchor at a predetermined position at the carrier base in the upper opening, the light guide module located inside the carrier base at a position under the base plane respective to the upper opening;

the at least one light source unit is located at the at least one lateral surface of the carrier base respective to the upper opening;

in the case that the PTBV reaches the predetermined position, the at least one light source unit projecting the at least one lateral light onto the PTBV such that said lateral light penetrates both the first finger member and the second finger member of the PTBV to simultaneously generate the fingerprint image and the vein image of the PTBV; and

the image-sensing unit is located inside the carrier base, the fingerprint image and the vein image of the PTBV entering the carrier base via the base plane of the upper opening, the light guide module leading the fingerprint image and the vein image to the image-sensing unit;

wherein the light guide module has one single prism unit separated into the fingerprint-detecting area and the vein-detecting area;

the position structure is formed as a finger-anchoring structure located on the base plane and further includes a front window, a rear window and a position rib between the front window and the rear window;

while an inter-member valley between the first finger member and the second finger member falls onto the position rib, the first finger member is anchored in the front window and the second finger member is anchored in the rear window; and

the fingerprint-detecting area is respective to the front window and the vein-detecting area is respective to the rear window;

the fingerprint-detecting area of the prism unit further includes the top surface, a bottom surface opposing to the top surface, an imaging surface connecting in between the top surface and the bottom surface, and an anti-reflection surface opposing to the imaging surface, the top surface neighboring the front window of the position structure;

when the PTBV is anchored at the predetermined position in the upper opening, the first finger member of the finger contacting the top surface of the fingerprint-detecting area, the fingerprint image entering the fingerprint-detecting area of the prism unit via the top surface of the fingerprint-detecting area, the fingerprint image reflected at least once by the bottom surface of the fingerprint-detecting area and then leaving the prism unit through the imaging surface of the fingerprint-detecting area, an oblique angle of the imaging surface of the fingerprint-detecting area causing the leaving fingerprint image to form on the image-sensing unit, the anti-reflection surface reducing the reflection; and

the vein-detecting area of the prism unit further includes said another top surface, another bottom surface opposing to the another top surface, another imaging surface connecting in-between the another top surface and the another bottom surface, and a reflection surface opposing to the another imaging surface and forming an oblique angle with the another bottom surface;

said another top surface of the vein-detecting area neighboring the rear window of the position structure;

when the PTBV is anchored at the predetermined position in the upper opening, the second finger member of the finger being above said another top surface of the vein-detecting area without any contact in between, the vein image entering the vein-detecting area of the prism unit via said another top surface of the vein-detecting area, the vein image reflected at least once individually by the reflection surface, said another top surface and said another bottom surface of the vein-detecting area, and then leaving the prism unit through said another imaging surface of the vein-detecting area, the oblique angle of said another imaging surface of the vein-detecting area causing the leaving vein image to form on the image-sensing unit;

an imaging optical path of the vein image depending on a vertical height between said another top surface and said another bottom surface of the vein-detecting area and a reflection frequency of the vein image inside the vein-detecting area, in which the reflection frequency is determined by the oblique angle between the reflection surface and said another bottom surface of the vein-detecting area.

7. The biometric authentication method according to claim 6, wherein the at least one light source unit further includes a plurality of Infrared Vertical-cavity Surface-emitting Lasers (IR-VCSELs), and a vertical height h1 between a mean central point of the at least one light source unit at a perpendicular direction to the mean central point, and the base plane of the upper opening is no less than one half of a mean vertical thickness h2 of the PTBV.

8. The biometric authentication method according to claim 7, wherein the at least one lateral light projected by the at least one light source unit defines a virtual central projection line, a projection direction of the fingerprint image and the vein image downward into the carrier base defines a virtual vertical projection line, and an angle θ

between the virtual central projection line and the virtual vertical projection line is ranged between 30 and 150 degrees.

9. The biometric authentication method according to claim 6, wherein the light guide module further includes a mirror and a mirror base for mounting the mirror, the mirror being formed as forming the vein-detecting area.

10. The biometric authentication method according to claim 6, wherein the biometric authentication device further includes a light-shielding plate located at the position structure.

11. The biometric authentication method according to claim 6, wherein the control module further includes:

a detecting element for detecting whether or not the PTBV is in the upper opening;

a controller, connecting electrically the detecting element, for determining the at least one light source unit to project the at least one lateral light according to a detection of the detecting element; and

an image-processing unit, connecting electrically the image-sensing unit and the controller, for performing a pre-management and a feature-capturing management while receiving the detection signal from the image-sensing unit;

wherein the pre-management performs de-noise and image optimization processes upon the detection signal, and the feature-capturing management extracts the fingerprint feature data from the fingerprint image and the vein feature data from the vein image of the detection signal.