US3716301A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fingerprint identification apparatus
Assignee: Unisys Corp
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Filing: 1971-03-17
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Granted: 1973-02-13
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Expires: 1991-03-17
Abstract
Abstract A coherent optical processor fingerprint identification apparatus in which identification is established by correlating an optical beam pattern representative of the finger to be identified with a prerecorded Fourier transform spatial filter of the fingerprint. Reliability of identification is improved by incorporating a mask in the processor so that the detector receives information primarily indicative of the correlation between certain features of the fingerprint and the spatial filter to the exclusion of other less significant features. Further improvement is achieved by means of dual detector affirmation-negation type signal processing techniques and, in the particular case of holographic filters various multiplexing techniques are also utilized for signal enhancement.
Inventors
- 👤 H Caulfield
- 👤 D Perkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:42
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/42; G02B27/46; G06; G06V; G06V40/00; G06V40/10; G06V40/12
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
168 words
A coherent optical processor fingerprint identification apparatus comprising input means for supporting a finger or fingerprint recording thereof which is to be identified, light source means for directing a coherent light beam onto said input means whereupon incidence of said beam on said finger or fingerprint recording causes a fingerprint data beam to be produced, Fourier transform spatial filter means including positive and negative transparency sections having a fingerprint representative pattern characterized by at least one information band disposed about a central region, focusing means disposed intermediate said input means and said filter means for converging the fingerprint data beam on to said filter means, and detector means positioned to receive light energy of the fingerprint data beam transmitted through said information band, said detector means including a first detector disposed to receive fingerprint data beam energy transmitted through the information band of the positive transparency section and a second detector disposed to receive fingerprint data beam energy transmitted through the information band of the negative transparency section.
Claim 2
Dependent Claim
168 words
A coherent optical processor fingerprint identification apparatus comprising input means for supporting a finger or fingerprint recording thereof which is to be identified, light source means for directing a coherent light beam onto said input means whereupon incidence of said beam on said finger or fingerprint recording causes a fingerprint data beam to be produced, Fourier transform spatial filter means including positive and negative transparency sections having a fingerprint representative pattern characterized by at least one information band disposed about a central region, focusing means disposed intermediate said input means and said filter means for converging the fingerprint data beam on to said filter means, and detector means positioned to receive light energy of the fingerprint data beam transmitted through said information band, said detector means including a first detector disposed to receive fingerprint data beam energy transmitted through the information band of the positive transparency section and a second detector disposed to receive fingerprint data beam energy transmitted through the information band of the negative transparency section.
Claim 3
Dependent Claim
168 words
A coherent optical processor fingerprint identification apparatus comprising input means for supporting a finger or fingerprint recording thereof which is to be identified, light source means for directing a coherent light beam onto said input means whereupon incidence of said beam on said finger or fingerprint recording causes a fingerprint data beam to be produced, Fourier transform spatial filter means including positive and negative transparency sections having a fingerprint representative pattern characterized by at least one information band disposed about a central region, focusing means disposed intermediate said input means and said filter means for converging the fingerprint data beam on to said filter means, and detector means positioned to receive light energy of the fingerprint data beam transmitted through said information band, said detector means including a first detector disposed to receive fingerprint data beam energy transmitted through the information band of the positive transparency section and a second detector disposed to receive fingerprint data beam energy transmitted through the information band of the negative transparency section.
Claim 4
Dependent Claim
168 words
A coherent optical processor fingerprint identification apparatus comprising input means for supporting a finger or fingerprint recording thereof which is to be identified, light source means for directing a coherent light beam onto said input means whereupon incidence of said beam on said finger or fingerprint recording causes a fingerprint data beam to be produced, Fourier transform spatial filter means including positive and negative transparency sections having a fingerprint representative pattern characterized by at least one information band disposed about a central region, focusing means disposed intermediate said input means and said filter means for converging the fingerprint data beam on to said filter means, and detector means positioned to receive light energy of the fingerprint data beam transmitted through said information band, said detector means including a first detector disposed to receive fingerprint data beam energy transmitted through the information band of the positive transparency section and a second detector disposed to receive fingerprint data beam energy transmitted through the information band of the negative transparency section.
Claim 5
Dependent Claim
43 words
The apparatus of claim 1 including means for obtaining a signal proportional to the difference between the output signals of said first and second detectors and indicating identification of an input finger or fingerprint recording when said difference signal exceeds a predetermined level.
Claim 6
Dependent Claim
43 words
The apparatus of claim 1 including means for determining the occurrence of said first and second detector output signals being respectively greater and lesser than corresponding discrete threshold levels to signify identification of a finger or fingerprint recording applied to said input means.
Claim 7
Dependent Claim
50 words
The apparatus of claim 1 wherein the spatial filter means is so constructed and arranged that the positive and negative transparency sections form a composite transparency having arcuate positive and negative transparency segments disposed about the central region which is axially aligned with the optical axis of the processor apparatus.
Claim 8
Dependent Claim
43 words
The apparatus of claim 4 including means for obtaining a signal proportional to the difference between the output signals of said first and second detectors and indicating identification of an input finger or fingerprint recording when said difference signal exceeds a predetermined level.
Claim 9
Dependent Claim
43 words
The apparatus of claim 4 including means for determining the occurrence of said first and second detector output signals being respectively greater and lesser than corresponding discrete threshold levels to signify identification of a finger or fingerprint recording applied to said input means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-13 | 1976-08-14 | 1977-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-13 | 1980-08-14 | 1981-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-13 | 1984-08-14 | 1985-02-13 | $7700.00 | Window Closed / Lapsed |