Latent fingerprint detectors and fingerprint scanners therefrom

• US 8,437,517 B2
• Filed: 03/16/2011
• Issued: 05/07/2013
• Est. Priority Date: 11/03/2010
• Status: Active Grant

• Current Assignee: Leidos Innovations Technology, Inc.
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Miesak, Edward, Gold, V. Edward Jr.
• Primary Examiner(s): Seth, Manav
• Application Number:
  US13/049,351
• Publication Number:
  US 20120105586A1
• Time in Patent Office: 783 Days
• Field of Search: None
• US Class Current: 382/124
• CPC Class Codes: G01N 21/8851 Scan or image signal processing specially adapted therefor, e.g. for scan signal adjustment, for detecting different kinds of defects, for compensating for structures, markings, edges G01N21/8806 and G01N21/93 - G01N21/95692 take precedence; optical measurement of dimensions G01B11/00; optical scanning G02B26/10; image transformation G06T3/00; computerised image enhancement G06T5/00; image processing per se for flaw detection G06T7/0002
• CPC Class Codes: G01N 21/94 Investigating contamination, e.g. dust G01N21/85 takes precedence
• CPC Class Codes: G01N 2201/06113 Coherent sources; lasers
• CPC Class Codes: G01N 2201/10 Scanning
• CPC Class Codes: G06V 40/1312 direct reading, e.g. contactless acquisition

Abstract

An automatic fingerprint system includes an optical sensor having a first light source that provides a collimated beam for interrogating a first sample surface, and a camera including a lens and a photodetector array having a camera field of view (FOV_CAMERA) large enough to image the first sample surface. The camera is critical angle positioned relative to the first light source to receive specular reflection (glare) from the first sample surface to generate image data from the glare. The first light source and camera have substantially equal and opposite numerical apertures (NAs). A computer or processor that includes reference fingerprint templates receives a digitized form of the image data, and includes data processing software for (i) comparing the image data to reference fingerprint templates to determine whether the image data includes at least one fingerprint and (ii) for generating a fingerprint image if the fingerprint is determined to be present.

Claims

1. An automatic fingerprint system, comprising:

an optical sensor, comprising;

a first light source that provides a collimated beam for interrogating sample surfaces including a first sample surface within a region of interest; and

a camera comprising a lens and a photodetector array optically coupled to said lens having a camera field of view (FOV_CAMERA), wherein said FOV_CAMERA is large enough to image at least substantially an entire area of said first sample surface, and wherein said camera is critical angle positioned relative to said first light source to receive specular reflection (glare) from said first sample surface, wherein said camera generates image data from said glare;

wherein said first light source and said camera have substantially equal and opposite numerical apertures (NAs);

a computer or processor having associated memory that includes reference fingerprint templates coupled to receive a digitized form of said image data from said camera, wherein said computer or processor includes data processing software for (i) comparing said digitized form of said image data to said reference fingerprint templates to determine whether said image data includes at least one fingerprint and (ii) for generating a fingerprint image if said fingerprint is determined to be present.

2. The system of claim 1, wherein said first light source provides a uniformly extended collimated beam across a full area of said first sample surface.

3. The system of claim 1, wherein said NA of said camera=0, and wherein said lens comprises a double telecentric lens.

4. The system of claim 1, wherein said first light source comprises a broadband light source.

5. The system of claim 4, wherein said broadband light source comprises a plurality of fluorescent tubes aligned parallel to one another.

6. The system of claim 1, wherein said collimated beam comprises a narrowband beam.

7. The system of claim 6, wherein said first light source comprises a narrowband light source or a broadband light source including a spectrometer, and wherein said narrowband beam is at one or more ultraviolet (UV) wavelengths or one or more long wave infrared (LWIR) wavelengths that each corresponds to significantly enhanced absorption of fingerprint oil as compared to an absorption of said fingerprint oil in a visible light range.

8. The system of claim 7, wherein said at least one UV wavelength is between 100 and 300 nm, and wherein said LWIR wavelength is at 3.42 μ

m, 5.71 μ

m, 6.9 μ

m, or 8.8 μ

m.

9. The system of claim 1, wherein said generating said fingerprint image comprises slope detection.

10. The system of claim 1, further comprising at least one non-critically aligned light source for generating diffuse reflection from said first sample surface.

11. The system of claim 1, further comprising a local memory associated with said computer or processor for storing said fingerprint, and a wireless transmitter for transmitting data representing said fingerprint to at least one remote site.

12. The system of claim 11, wherein said computer or said processor and said wireless transmitter is provided by a portable computing device, said portable computing device utilizing said associated memory for storing said fingerprint, said associated memory including software for encoding said fingerprint into a predetermined format.

13. An automatic fingerprint scanning system, comprising:

an optical sensor, comprising;

a first light source that provides a collimated beam for interrogating sample surfaces including a first sample surface within a region of interest; and

a camera comprising a lens and a photodetector array optically coupled to said lens having a camera field of view (FOV_CAMERA), wherein said FOV_CAMERA is large enough to image at least substantially an entire area of said first sample surface, and wherein said camera is critical angle positioned relative to said first light source to receive specular reflection (glare) from said first sample surface, wherein said camera generates image data from said glare;

wherein said first light source and said camera have substantially equal and opposite numerical apertures (NAs);

a computer or processor having associated memory that includes reference fingerprint templates coupled to receive a digitized form of said image data from said camera, wherein said computer or processor includes data processing software for (i) comparing said digitized form of said image data to said reference fingerprint templates to determine whether said image data includes at least one fingerprint and (ii) for generating a fingerprint image if said fingerprint is determined to be present, and

at least one scanner mechanically coupled to said optical sensor for scanning said optical sensor across a plurality of different surface portions within said region of interest,

wherein said critical angle positioning of said first light source to said FOV of said camera is maintained during said scanning.

14. The system of claim 13, wherein said NA of said camera=0, and wherein said lens comprises a double telecentric lens.

15. The system of claim 13, wherein said first light source comprises a broadband light source, and wherein said broadband light source comprises a plurality of fluorescent tubes aligned parallel to one another.

16. The system of claim 13, wherein said collimated beam comprises a narrowband beam, and wherein said collimated beam is at one or more ultraviolet (UV) wavelengths or one or more long wave infrared (LWIR) wavelengths that each corresponds to significantly enhanced absorption of fingerprint oil as compared to an absorption of said fingerprint oil in a visible light range.

17. The system of claim 16, wherein said at least one UV wavelength is between 100 and 300 nm, and wherein said LWIR wavelength is at 3.42 μ

m, 5.71 μ

m, 6.9 μ

m, or 8.8 μ

m.

18. The system of claim 13, wherein said generating said fingerprint image comprises slope detection.

19. The system of claim 13, further comprising at least one non-critically aligned light source for generating diffuse reflection from said first sample surface.

20. The system of claim 13, further comprising a local memory associated with said computer or processor for storing said fingerprint, and a wireless transmitter for transmitting data representing said fingerprint to at least one remote site.

21. The system of claim 20, wherein said computer or said processor and said wireless transmitter is provided by a portable computing device, said portable computing device utilizing said associated memory for storing said fingerprint, said associated memory including software for encoding said fingerprint into a predetermined format.

22. The system of claim 13, wherein said scanner comprises a robotic arm.

23. The system of claim 22, wherein said system further comprises a remote sensing device for generating a region image (3D) across said region of interest, wherein said region image is used by said robot arm for its movement to image across said region of interest.

24. The system of claim 23, wherein said remote sensing device comprises Light Detection And Ranging (LIDAR) device.