Patent ID: 6459486
Filing Date: 2002-10-01
Classification: G01H

Abstract:
A Sagnac interferometer based sensor system including:first light source means for producing a first light beam having: a coherence length; a first beamsplitter positioned to receive the first light beam and split it into second and third light beams; a second beamsplitter positioned to receive the second and third light beams and split the second light beam into fourth and fifth light beams and the third light beams into sixth and seventh beams; a first optical pathway extending between said first and second beamsplitters on which the second light beam travels; a second optical pathway of different length from said first optical pathway extending between said first and second beamsplitters on which the third light beam travels, the different length of said first and second optical pathways exceeding said coherence length; a third optical pathway extending from said second beamsplitter, on which the fourth and sixth light beams are impressed, said third optical pathway being exposed to at least one effect to be sensed; beam reversal means positioned to direct the fourth and sixth light beams that been effected by the at least one effect back through said the at least one effect to said second beamsplitter; detector means operatively connected to said first beamsplitter to receive an interference light beam from said first beamsplitter and to detect the at least one effect therefrom; and said first light source means produce a first light beam having a plurality of colors and wherein said beam reversal means include: a plurality of color reflecting elements spaced along said third optical pathway, and wherein said detector means include: a plurality of output detectors; and a wavelength division multiplexing element for splitting the plurality of colors onto said plurality of output detectors.