Patent ID: 9726546
Date: 2017-08-08
CPC Classifications: G01D,G01J,G01K

Claim:
1. A distributed optical sensing apparatus for determining of a primary quantity as a quantity of interest along an optical sensing waveguide, which is an optical device under test, wherein the spatial distribution of the primary quantity along the waveguide is to be determined with the apparatus, the distributed optical sensing apparatus comprising: an electromagnetic radiation source adapted for coupling electromagnetic radiation into the waveguide to thereby generate in the waveguide a first response radiation and a second response radiation, the second response radiation being different from the first response radiation; a detector device adapted for providing a first measurement signal indicative of the first response radiation; the detector device being further adapted for providing a second measurement signal indicative of the second response radiation; an evaluation unit adapted for deriving a secondary quantity based on the first measurement signal and the second measurement signal; the evaluation unit being further adapted for deriving the primary quantity based on the secondary quantity and at least one of the first measurement signal and the second measurement signal; the evaluation unit being further adapted for sampling the first measurement signal so as to generate a plurality of first values based on the first measurement signal; the evaluation unit being further adapted for sampling the second measurement signal so as to generate a plurality of second values based on the second measurement signal; wherein each of the first values and the second values corresponds to a spatial region of the waveguide; the evaluation unit being further adapted for deriving a value of the primary quantity based on a value of the secondary quantity and at least one of a first value out of the plurality of first values and a second value out of the plurality of second values, wherein the value of the secondary quantity, the at least one of the first value and the second value, and the value of the primary quantity derived therefrom correspond to the same spatial region of the waveguide; and the evaluation unit being further adapted for optimizing, for said spatial region of the waveguide, the secondary quantity corresponding to said spatial region different from the primary quantity corresponding to said spatial region.