Tension-tuned acousto-optic bandpass filter
AssigneeThe United States of America as represented by the National Security Agency
InventorDuane Anthony Satorius
Life of this patent
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Abstract
Device whereby one or more bands of optical wavelengths may be selected for further transmission. All light within the optical bandwidth of operation is first coupled from the core mode of an optical fiber to a specific cladding mode by a chirped broadband cladding mode coupler. These cladding mode lightwaves then enter a narrow-band core mode coupler whereby selected optical bands of wavelengths, tuned by the tension on the optical fiber, are re-coupled back into the core of the optical fiber. The chirped broadband cladding mode coupler is isolated from the narrow-band core mode coupler by an acoustic absorber to limit the acoustic interaction between them.
Claims14
A tension-tuned acousto-optic bandpass filter, comprising:
- a single-mode optical fiber, with a longitudinal axis, core, concentric cladding over the core, and proximal and distal ends;
- a broadband cladding mode coupler further comprising a first longitudinal length of the optical fiber closer to the proximal end of the optical fiber, wherein said first longitudinal length has a chirped diameter, and at least one first acoustic-wave generator coupled to the optical fiber within the first longitudinal length;
- a narrow-band core mode coupler further comprising a second longitudinal length of the optical fiber closer to the distal end of the optical fiber and at least one second acoustic-wave generator coupled to the optical fiber within the second longitudinal length;
- an acoustic absorber deployed and coupled to the optical fiber between said broadband cladding mode coupler and said narrow-band core mode coupler;
- and
- means for applying an adjustable tension to said second longitudinal length of the optical fiber.
A tension-tuned acousto-optic bandpass filter, comprising:
- a single-mode optical fiber, with a longitudinal axis, core, concentric cladding over the core, and proximal and distal ends;
- a broadband cladding mode coupler further comprising a first longitudinal length of the optical fiber closer to the proximal end of the optical fiber, wherein said first longitudinal length has a chirped diameter, and at least one first acoustic-wave generator coupled to the optical fiber within the first longitudinal length;
- a narrow-band core mode coupler further comprising a second longitudinal length of the optical fiber closer to the distal end of the optical fiber and at least one second acoustic-wave generator coupled to the optical fiber within the second longitudinal length;
- an acoustic absorber deployed and coupled to the optical fiber between said broadband cladding mode coupler and said narrow-band core mode coupler;
- and
- means for applying an adjustable tension to said single-mode optical fiber.
Dependencies are inferred from the claim text.