Accession Number:

ADD015617

Title:

Fiber Optic Interferometer Configuration with Pump-Induced Phase Carrier.

Descriptive Note:

Patent Application, Filed 1 May 92,

Corporate Author:

DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s):

Report Date:

1992-05-01

Pagination or Media Count:

21.0

Abstract:

An interferometric fiber optic sensor and method are provided for controlling the optical phase of a fiber interferometer by an optically induced change in the refractive index for one arm of the fiber interferometer and providing a passive all-optical phase shift interrogation in response to this dependency on the optically induced change in the refractive index. The interferometric fiber optic sensor includes a laser source for generating light at a first predetermined wavelength, a fiber interferometer coupled to the laser source and having first and second fiber arms with a predetermined optical path difference between the fiber arms, a predetermined one of the first and second fiber arms being doped with an element for introducing an optically adjustable absorption spectrum, and a pump laser coupled to the predetermined fiber arm for generating light at a second predetermined wavelength so that an effective index for a guided mode in the predetermined fiber arm and a phase delay of the light passing through the fiber interferometer are changed. As a result, the interferometric fiber optic sensor and method allows the phase interrogation of the fiber interferometer by using a passive all-optical approach based on a pump induced refractive index change in the doped fiber arm so that balanced all fiber interferometer elements are used as sensors for eliminating laser induced phase noise.

Subject Categories:

  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE