Granted Patent B2

US 8,153,956 · App. 13/170,235 · Granted Apr 10, 2012

Abstract

Claims (13)

1. An interrogator for a plurality of sensor fiber optic gratings comprising:

a broadband optical source;

at least one beam splitter directing output of the optical source to the sensor fiber optic gratings;

at least one linear filter for converting changes in peak reflection wavelength to changes in intensity;

at least one optical receiver;

at least one amplifier associated with each optical receiver; and

means for compensating for masking of one sensor fiber optic grating by another.

2. The interrogator of claim 1 wherein the means for compensating implements a method comprising the steps of:

calibrating an error function using a pair of known fiber optic gratings arranged such that one masks the other;

measuring a center wavelength of the unmasked fiber optic grating;

determining an uncompensated wavelength of the unmasked fiber optic grating; and

correcting the uncompensated wavelength with a correction factor determined from the error function using the measured center wavelength of the unmasked fiber optic grating.

3. The interrogator of claim 1 wherein the broadband optical source is one of a Light Emitting Diode (LED), a Superluminescent Light Emitting Diode (SLED), an Amplified Spontaneous Emission (ASE) source, and a Semiconductor Optical Amplifier (SOA).

Assignments (9)