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Duo-frame normalization technique

Assignee: United States Department of the Army
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Filing: 1994-05-17
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Granted: 1995-07-18
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Expires: 2014-05-17
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Abstract

Abstract A duo-frame normalization technique and system for use in range gate imag to determine a range coded image by use of two image frames. A transmitter emits a modulated energy pulse which is not gated when received by a single gated imaging camera to obtain an integrated first image frame and gated by the same camera when received as an integrated second image frame. The second integrated frame is divided by the first integrated frame to yield a range coded pixel intensity image. Three gated imagining cameras can also be used that share common imaging optics via filters and beam splitters so as to compensate for phenomenological issues that can vary the signals from one frame to another and lead to degraded range images.

Inventors

  • 👤 John E. Nettleton
  • 👤 Dallas N. Barr

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 02:59
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/18; H04N7/181; G; G01; G01S; G01S17/00; G01S17/88; G01S17/89

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 161 words
A duo-frame normalization technique for use in range gate imaging to compensate for phenomenological effects, including the steps of: generating an energy pulse; transmitting over a range interval the energy pulse to a target; simultaneously receiving, a) ambient light present over an open gated range as an integrated ambient image; b) a reflected energy pulse from said target over the open-gated range as an integrated first gate image; c) the reflected energy pulse from said target over a shortened gate range as an integrated second gate image; normalizing the integrated ambient image; subtracting the integrated normalized ambient image from both the integrated first gate image and the integrated second gate image, to yield a first and second frame integration; dividing the second frame integration by the first frame integration whereby a range-coded image is obtained in a time that is relatively short as compared to dynamic scene effects so as to substantially remove all dynamic scene effects from the range-coded image.
Claim 2
Dependent Claim 161 words
A duo-frame normalization technique for use in range gate imaging to compensate for phenomenological effects, including the steps of: generating an energy pulse; transmitting over a range interval the energy pulse to a target; simultaneously receiving, a) ambient light present over an open gated range as an integrated ambient image; b) a reflected energy pulse from said target over the open-gated range as an integrated first gate image; c) the reflected energy pulse from said target over a shortened gate range as an integrated second gate image; normalizing the integrated ambient image; subtracting the integrated normalized ambient image from both the integrated first gate image and the integrated second gate image, to yield a first and second frame integration; dividing the second frame integration by the first frame integration whereby a range-coded image is obtained in a time that is relatively short as compared to dynamic scene effects so as to substantially remove all dynamic scene effects from the range-coded image.

References Cited (Backward Citations)

US4839569A Cited
US4915498A Cited
US5013917A Cited
US5056914A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-07-17 1999-01-16 1999-07-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-07-17 2003-01-16 2003-07-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-07-17 2007-01-16 2007-07-18 $7700.00 Window Closed / Lapsed

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