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US4385831A Expired / Lapsed US ⏱️ 0.0 years remaining

Device for investigation of a finger relief

Assignee: Siemens Corp
•
Filing: 1980-09-22
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Granted: 1983-05-31
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Expires: 2000-09-22
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Abstract

Abstract The fingerprint sensor device derives an electric output signal in accordance with the topographic relief of a finger under investigation. The sensor incorporates a radiation source, a fingerbed, a first radiation transmitting device, a scanning device, a second radiation transmitting device, and a measuring device responsive to the radiation. The fingerbed has an opening for passing a beam of radiation (light or ultrasound, for instance) from the source therethrough. The scanning device scans this beam of radiation across the finger. Thus, the finger relief is directly scanned by a beam of small impingement spot. The back scattered radiation is directed to the measuring device. Here, the intensity distribution is determined.

Inventors

  • 👤 Hartwig Ruell

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 03:16
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/117; A61B5/1171; A61B5/1172; G; G06; G06V; G06V40/00; G06V40/10; G06V40/12; G06V40/13; G06V40/1312

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 212 words
A device for investigating the pattern of a finger, comprising in combination: (a) a source for emitting a beam of radiation; (b) a fingerbed for supporting said finger, said fingerbed defining an opening which leaves free an area of the skin of said finger for investigation, when said finger rests in said fingerbed; (c) means for passing said beam of radiation to said area under investigation, said beam thereby forming a spot of impingement on said area which has an extension that is smaller than the distance between two adjacent ridges on said skin under investigation; (d) means for raster scanning said impingement spot in two dimensions over said area under investigation, said finger skin area thereby scattering back a beam of radiation which is modulated in accordance with said pattern on said area, said scanning means comprising a reflection hologram which is tiltable about an axis; (e) measuring means responsive to said radiation; (f) lens means for collecting and transmitting said back-scattered beam of radiation to said measuring means, said measuring means thereby measuring the distribution of the back-scattered radiation in accordance with the ridge-valley pattern of said area under investigation; and (g) output means associated with said measuring means for producing an output signal representing the intensity of back-scattered radiation.
Claim 2
Independent Claim 212 words
A device for investigating the pattern of a finger, comprising in combination: (a) a source for emitting a beam of radiation; (b) a fingerbed for supporting said finger, said fingerbed defining an opening which leaves free an area of the skin of said finger for investigation, when said finger rests in said fingerbed; (c) means for passing said beam of radiation to said area under investigation, said beam thereby forming a spot of impingement on said area which has an extension that is smaller than the distance between two adjacent ridges on said skin under investigation; (d) means for raster scanning said impingement spot in two dimensions over said area under investigation, said finger skin area thereby scattering back a beam of radiation which is modulated in accordance with said pattern on said area, said scanning means comprising a reflection hologram which is tiltable about an axis; (e) measuring means responsive to said radiation; (f) lens means for collecting and transmitting said back-scattered beam of radiation to said measuring means, said measuring means thereby measuring the distribution of the back-scattered radiation in accordance with the ridge-valley pattern of said area under investigation; and (g) output means associated with said measuring means for producing an output signal representing the intensity of back-scattered radiation.
Claim 3
Dependent Claim 19 words
The device according to claim 1, wherein said radiation source is adapted to emit a beam of electromagnetic waves.
Claim 4
Dependent Claim 17 words
The device according to claim 2, wherein said radiation source is adapted to emit a light beam.
Claim 5
Dependent Claim 13 words
The device according to claim 3, wherein said light source is a laser.
Claim 6
Dependent Claim 30 words
The device according to claim 3, wherein said means for passing said beam of radiation to said finger contains a first lens for focussing said beam on said finger area.
Claim 7
Dependent Claim 32 words
The device according to claim 3, wherein said means for transmitting said reflected beam of radiation contains a second lens for casting an image of said finger area onto said measuring means.
Claim 8
Dependent Claim 28 words
The device according to claim 3, wherein said measuring means comprises a photodetector having a light sensitive area for measuring the distribution of light impinging on said area.

References Cited (Backward Citations)

US3201961A Cited
US3516059A Cited
CA950587A Cited
US3961838A Cited
US4053228A Cited
US4120585A Cited
US4227805A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-05-30 1986-11-29 1987-05-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-05-30 1990-11-29 1991-05-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-05-30 1994-11-29 1995-05-31 $7700.00 Window Closed / Lapsed

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