US5864296A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fingerprint detector using ridge resistance sensor
Assignee: Northrop Grumman Systems Corp
•
Filing: 1997-05-19
•
Granted: 1999-01-26
•
Expires: 2017-05-19
Abstract
Abstract A technique for detecting and verifying a fingerprint includes a skin resistance sensing array for translating the skin resistance of a fingertip into an electrical signal. The fingertip is moved relative to the skin resistance sensing array in a first linear direction for producing a reference trajectory signal which is stored into a memory. The fingertip is again moved relative to the skin resistance sensing array in a second linear direction for producing a sample trajectory signal. The second linear direction of movement is offset from the first linear direction of movement by a predetermined angle. A processor is provided for performing a set of functions on the reference trajectory signal and the sample trajectory signal. The sample trajectory signal is correlated with the reference trajectory signal for producing a verification signal related to the probability that the fingertip generated both the sample trajectory signal and the reference trajectory signal.
Inventors
- 👤 Eric L. Upton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:13
CPC Classifications
G; G06; G06V; G06V40/00; G06V40/10; G06V40/12; G06V40/13; G06V40/1306; G06V40/1335; G07; G07C; G07C9/00; G07C9/20; G07C9/22; G07C9/25; G07C9/257; G07C9/26
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
150 words
A method for detecting and verifying a fingerprint comprising the steps of: providing a skin resistance sensing array, the skin resistance sensing array translating skin resistance of a fingertip into an electrical signal; moving the fingertip relative to the skin resistance sensing array in a first linear direction for producing a reference trajectory signal; storing the reference trajectory signal in a memory; moving the fingertip relative to the skin resistance sensing array in a second linear direction for producing a sample trajectory signal, the second linear direction being offset from the first linear direction by a predetermined angle; providing a processor for performing a set of functions on the reference trajectory signal and the sample trajectory signal; correlating the sample trajectory signal with the reference trajectory signal; and producing a verification signal related to the probability that the fingertip generated both the sample trajectory signal and the reference trajectory signal.
Claim 2
Independent Claim
150 words
A method for detecting and verifying a fingerprint comprising the steps of: providing a skin resistance sensing array, the skin resistance sensing array translating skin resistance of a fingertip into an electrical signal; moving the fingertip relative to the skin resistance sensing array in a first linear direction for producing a reference trajectory signal; storing the reference trajectory signal in a memory; moving the fingertip relative to the skin resistance sensing array in a second linear direction for producing a sample trajectory signal, the second linear direction being offset from the first linear direction by a predetermined angle; providing a processor for performing a set of functions on the reference trajectory signal and the sample trajectory signal; correlating the sample trajectory signal with the reference trajectory signal; and producing a verification signal related to the probability that the fingertip generated both the sample trajectory signal and the reference trajectory signal.
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein the predetermined angle of offset between the first linear direction and the second linear direction is an acute angle.
Claim 4
Dependent Claim
24 words
The method of claim 1 wherein the predetermined angle of offset between the first linear direction and the second linear direction is 90 degrees.
Claim 5
Dependent Claim
17 words
The method of claim 1 wherein the skin resistance sensing array includes a plurality of sensing elements.
Claim 6
Dependent Claim
28 words
The method of claim 1 wherein the skin resistance sensing array includes twelve sensing elements for producing the skin resistance trajectory signals for processing by a verification algorithm.
Claim 7
Dependent Claim
20 words
The method of claim 5 wherein the skin resistance sensing array includes two sensing elements for generating a velocity function.
Claim 8
Dependent Claim
30 words
The method of claim 1 wherein the set of functions includes generating an intersection matrix of common data points relating to the reference trajectory signal and the sample trajectory signal.
Claim 9
Dependent Claim
28 words
The method of claim 7 wherein the step of correlating the signals includes correlating the common data points of the sample trajectory signal with the reference trajectory signal.
Claim 10
Dependent Claim
18 words
The method of claim 8 wherein the step of correlating the signals includes performing a matched filter algorithm.
Claim 11
Independent Claim
176 words
A method for detecting and verifying a fingerprint comprising the steps of: providing a fingerprint verification terminal; providing a skin resistance sensing array coupled to the fingerprint verification terminal, the skin resistance sensing array translating skin resistance of a fingertip into an electrical signal; moving the fingertip relative to the skin resistance sensing array in a first linear direction for producing a reference trajectory signal; encoding the reference trajectory signal onto a data carrier card; moving the fingertip relative to the skin resistance sensing array in a second linear direction for producing a sample trajectory signal, the second linear direction being offset from the first linear direction by a predetermined angle; reading the reference trajectory signal from the data carrier card into a memory; providing a processor for performing a set of functions on the reference trajectory signal and the sample trajectory signal; correlating the sample trajectory signal with the reference trajectory signal; and producing a verification signal related to the probability that the fingertip generated both the sample trajectory signal and the reference trajectory signal.
Claim 12
Independent Claim
176 words
A method for detecting and verifying a fingerprint comprising the steps of: providing a fingerprint verification terminal; providing a skin resistance sensing array coupled to the fingerprint verification terminal, the skin resistance sensing array translating skin resistance of a fingertip into an electrical signal; moving the fingertip relative to the skin resistance sensing array in a first linear direction for producing a reference trajectory signal; encoding the reference trajectory signal onto a data carrier card; moving the fingertip relative to the skin resistance sensing array in a second linear direction for producing a sample trajectory signal, the second linear direction being offset from the first linear direction by a predetermined angle; reading the reference trajectory signal from the data carrier card into a memory; providing a processor for performing a set of functions on the reference trajectory signal and the sample trajectory signal; correlating the sample trajectory signal with the reference trajectory signal; and producing a verification signal related to the probability that the fingertip generated both the sample trajectory signal and the reference trajectory signal.
Claim 13
Dependent Claim
25 words
The method of claim 10 wherein the predetermined angle of offset between the first linear direction and the second linear direction is an acute angle.
Claim 14
Dependent Claim
24 words
The method of claim 10 wherein the predetermined angle of offset between the first linear direction and the second linear direction is 90 degrees.
Claim 15
Dependent Claim
17 words
The method of claim 10 wherein the skin resistance sensing array includes a plurality of sensing elements.
Claim 16
Dependent Claim
28 words
The method of claim 10 wherein the skin resistance sensing array includes twelve sensing elements for producing the skin resistance trajectory signals for use by a verification algorithm.
Claim 17
Dependent Claim
20 words
The method of claim 14 wherein the skin resistance sensing array includes two sensing elements for generating a velocity function.
Claim 18
Independent Claim
181 words
A method for detecting and verifying a fingerprint comprising the steps of: providing a skin resistance sensing array, the skin resistance sensing array translating skin resistance of a fingertip into an electrical signal, and further including a plurality of sensing elements, at least two of the sensing elements being used for generating a velocity function; moving the fingertip relative to the skin resistance sensing array in a first linear direction for producing a reference trajectory signal; storing the reference trajectory signal in a memory; moving the fingertip relative to the skin resistance sensing array in a second linear direction for producing a sample trajectory signal, the second linear direction being offset from the first linear direction by a predetermined angle; providing a processor for generating an intersection matrix of common data points relating to the reference trajectory signal and the sample trajectory signal; correlating the common data points of the sample trajectory signal with the reference trajectory signal; and producing a verification signal related to the probability that the fingertip generated both the sample trajectory signal and the reference trajectory signal.
Claim 19
Independent Claim
181 words
A method for detecting and verifying a fingerprint comprising the steps of: providing a skin resistance sensing array, the skin resistance sensing array translating skin resistance of a fingertip into an electrical signal, and further including a plurality of sensing elements, at least two of the sensing elements being used for generating a velocity function; moving the fingertip relative to the skin resistance sensing array in a first linear direction for producing a reference trajectory signal; storing the reference trajectory signal in a memory; moving the fingertip relative to the skin resistance sensing array in a second linear direction for producing a sample trajectory signal, the second linear direction being offset from the first linear direction by a predetermined angle; providing a processor for generating an intersection matrix of common data points relating to the reference trajectory signal and the sample trajectory signal; correlating the common data points of the sample trajectory signal with the reference trajectory signal; and producing a verification signal related to the probability that the fingertip generated both the sample trajectory signal and the reference trajectory signal.
Claim 20
Dependent Claim
25 words
The method of claim 16 wherein the predetermined angle of offset between the first linear direction and the second linear direction is an acute angle.
Claim 21
Dependent Claim
24 words
The method of claim 16 wherein the predetermined angle of offset between the first linear direction and the second linear direction is 90 degrees.
Claim 22
Dependent Claim
28 words
The method of claim 16 wherein the skin resistance sensing array includes twelve sensing elements for producing the skin resistance trajectory signals for processing by a verification algorithm.
Claim 23
Dependent Claim
18 words
The method of claim 16 wherein the step of correlating the signals includes performing a matched filter algorithm.
References Cited (Backward Citations)
US3781855A
Cited
US3639905A
Cited
US4582985A
Cited
US4429413A
Cited
US4784484A
Cited
US5088817A
Cited
US4983036A
Cited
US5258922A
Cited
US5195145A
Cited
US5325442A
Cited
US5267324A
Cited
US5079949A
Cited
US5400662A
Cited
US5373181A
Cited
US5559504A
Cited
US5745046A
Cited
US5546471A
Cited
US5757278A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-01-25 | 2002-07-27 | 2003-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-01-25 | 2006-07-27 | 2007-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-01-25 | 2010-07-27 | 2011-01-26 | $7700.00 | Window Closed / Lapsed |