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Nonlinear optical protection against frequency agile lasers

Assignee: United States Department of the Navy
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Filing: 1988-08-04
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Granted: 1990-03-20
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Expires: 2008-08-04
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Abstract

Abstract An eye protection or equipment filter device for protection from laser eny is disclosed. The device may be in the form of a telescope, binoculars, goggles, or constructed as part of equipment such as image intensifiers or range designators. Optical elements focus the waist of the beam within a nonlinear frequency-doubling crystal or nonlinear optical element or fiber. The nonlinear elements produce a harmonic outside the visible spectrum in the case of crystals, or absorb the laser energy in the case of nonlinear fibers. Embodiments include protectors for the human eye as well as filters for sensitive machinery such as TV cameras, FLIR systems or other imaging equipment.

Inventors

  • 👤 Vaughn P. McDowell

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 14:16
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/35; G02F1/37; A; A61; A61F; A61F9/00; A61F9/02; A61F9/022; A61F9/023; B; B23; B23K; B23K26/00; B23K26/70; B23K26/702; B23K26/706; G02B; G02B6/00; G02B6/24; G02B6/255; G02B6/2552; G02B6/42; G02B6/4296

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 93 words
An optical hardening device for eye protection against frequency agile lasers comprising: a first and second means for focusing incoming optical energy; a first and second bandpass filter in spaced relationship with said means for focusing incoming optical energy, whereby unwanted optical wavelengths are filtered; a first and second passive, coherent-energy attenuating element comprised of an array of second harmonic nonlinear optic fibers spaced at the focal points of the incoming energy focused by said means for focusing whereby all first elements are in spaced parallel relationship to all second elements, forming binoculars.
Claim 2
Dependent Claim 93 words
An optical hardening device for eye protection against frequency agile lasers comprising: a first and second means for focusing incoming optical energy; a first and second bandpass filter in spaced relationship with said means for focusing incoming optical energy, whereby unwanted optical wavelengths are filtered; a first and second passive, coherent-energy attenuating element comprised of an array of second harmonic nonlinear optic fibers spaced at the focal points of the incoming energy focused by said means for focusing whereby all first elements are in spaced parallel relationship to all second elements, forming binoculars.
Claim 3
Dependent Claim 67 words
An optical hardening device for protection against frequency agile lasers comprising: an array of second harmonic, nonlinear, optical fibers having the properties of generating and absorbing a second harmonic from an input, and a means for focusing incoming optical energy into an image for inputting to said array, and a bandpass filter in spaced relationship between said array and said means for focusing to filter unwanted frequencies.
Claim 4
Dependent Claim 67 words
An optical hardening device for protection against frequency agile lasers comprising: an array of second harmonic, nonlinear, optical fibers having the properties of generating and absorbing a second harmonic from an input, and a means for focusing incoming optical energy into an image for inputting to said array, and a bandpass filter in spaced relationship between said array and said means for focusing to filter unwanted frequencies.
Claim 5
Dependent Claim 16 words
An optical hardening device according to claim 2 wherein said nonlinear optical fibers are organic polymers.
Claim 6
Dependent Claim 36 words
An optical hardening device for protection against frequency agile lasers according to claim 2 wherein said bandpass filter filters ultraviolet and infrared radiation from the array thus limiting the output of said array to visible spectrum.
Claim 7
Dependent Claim 18 words
An optical hardening device according to claim 2 wherein said array of fibers are formed of liquid crystal.

References Cited (Backward Citations)

US3620597A Cited
US4176919A Cited
US4515429A Cited
US4776677A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-03-19 1993-09-18 1994-03-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-03-19 1997-09-18 1998-03-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-03-19 2001-09-18 2002-03-20 $7700.00 Window Closed / Lapsed

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