Patent ID: 6525308
Filing Date: 2003-02-25
Classification: G01J

Abstract:
A wavelength detector configuration for detecting the Bragg wavelength of a plurality of Bragg gratings in at least one FBG sensor, in which light reflected by said Bragg gratings is conducted by one fiber coupler into a distributor fiber coupler being arranged for distributing said reflected light to a plurality of pairs of detector channels, each pair of detector channels corresponding to one of said Bragg gratings and each channel containing a detector whereby an evaluator device with a processing and computing circuit is provided for determining quotients of the detector signals of each channel pair and for determining said Bragg wavelengths for each channel pair from said quotients wherein said detectors of each pair of detector channels exhibit narrow band spectral sensitivities that overlap with one another and whose central wavelengths of maximum sensitivity span a wavelength range containing the Bragg wavelength of the corresponding Bragg grating.