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US5410147A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical communication system using coplanar light modulators

Assignee: Lockheed Martin Corp
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Filing: 1992-08-20
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Granted: 1995-04-25
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Expires: 2012-08-20
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Abstract

Abstract An optical communications system includes apparatus for interferometric signaling in which light signals are propagated from a first location so as to form at least one predetermined interference pattern at a second location remote from the first location and then the received light signals are demodulated at the second location. The apparatus includes a substantially coherent light source and a plurality of adjacent, substantially coplanar optical modulators in the path of the emitted light.

Inventors

  • 👤 Nabeel A. Riza
  • 👤 John E. Hershey
  • 👤 Amer A. Hassan

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 11:09
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/50; G; G02; G02F; G02F1/00; G02F1/01; G02F1/21

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 48 words
Apparatus for use in communications comprising: a substantially coherent light source; and a plurality of adjacent, substantially coplanar, optical modulators, the plane formed by said modulators being in the path of the light emitted by said source and oriented at a predetermined angle with respect to said path.
Claim 2
Dependent Claim 48 words
Apparatus for use in communications comprising: a substantially coherent light source; and a plurality of adjacent, substantially coplanar, optical modulators, the plane formed by said modulators being in the path of the light emitted by said source and oriented at a predetermined angle with respect to said path.
Claim 3
Dependent Claim 13 words
The apparatus of claim 1, wherein said predetermined angle is approximately ninety degrees.
Claim 4
Dependent Claim 28 words
The apparatus of claim 1, wherein at least one of said optical modulators alters the light incident upon it so as to provide an interferometrically encoded light signal.
Claim 5
Dependent Claim 32 words
The apparatus of claim 3, wherein said at least one modulator comprises a modulator for altering incident light selected from the group consisting essentially of a phase modulator and an amplitude modulator.
Claim 6
Dependent Claim 17 words
The apparatus of claim 3, wherein each of said modulators comprises an electronically controlled liquid crystal cell.
Claim 7
Dependent Claim 17 words
The apparatus of claim 3, wherein each of said modulators comprises a film for modulating incident light.
Claim 8
Dependent Claim 49 words
The apparatus of claim 3, and further comprising a beam diverger positioned in the path of the light emitted by said source between said source and said modulators and a beam former positioned in the path of the light emitted by said source between said diverger and said modulators.
Claim 9
Dependent Claim 39 words
The apparatus of claim 7, and further comprising an array of focusing lenses positioned in the path of the light emitted by said source between said beam former and said modulators for focusing the light passing through said lenses.
Claim 10
Dependent Claim 28 words
The apparatus of claim 8, and further comprising an array of recollimating lenses positioned adjacent said modulators for recollimating a portion of the light emerging from said modulators.
Claim 11
Dependent Claim 24 words
The apparatus of claim 7, and further comprising a lens positioned adjacent said modulators for transforming a portion of the light leaving said modulators.
Claim 12
Dependent Claim 49 words
The apparatus of claim 10, and further comprising a plurality of optical fibers adjacent said lens for transmitting a portion of the light passing through said lens, the flat ends of said fibers adjacent said lens being oriented substantially perpendicular to the direction of propagation of said light portion.
Claim 13
Independent Claim 96 words
A method for transmitting information, comprising the steps of: generating a beam of coherent light; expanding said beam of coherent light to form an expanded beam; collimating said expanded beam to form a collimated expanded beam of light; and modulating a plurality of portions of said collimated expanded beam of light by a like plurality of coplanar light modulators located within said collimated expanded beam of light and controlled by mutually independent sources of information, to thereby form a collimated beam of modulated light in which different portions of the beam are modulated by independent information.
Claim 14
Independent Claim 96 words
A method for transmitting information, comprising the steps of: generating a beam of coherent light; expanding said beam of coherent light to form an expanded beam; collimating said expanded beam to form a collimated expanded beam of light; and modulating a plurality of portions of said collimated expanded beam of light by a like plurality of coplanar light modulators located within said collimated expanded beam of light and controlled by mutually independent sources of information, to thereby form a collimated beam of modulated light in which different portions of the beam are modulated by independent information.
Claim 15
Dependent Claim 28 words
A method according to claim 12 wherein said step of modulating includes the step of focusing portions of said collimated expanded beam of light onto said light modulators.

References Cited (Backward Citations)

US3218390A Cited
US3363103A Cited
US3755676A Cited
US4691312A Cited
US4699468A Cited
US4867522A Cited
US5047845A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-04-24 1998-10-24 1999-04-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-04-24 2002-10-24 2003-04-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-04-24 2006-10-24 2007-04-25 $7700.00 Window Closed / Lapsed

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