Experimental evaluation of noise in optical fibers employed in optical sensors is presented. A single-mode fiber and two multimode fibers with different core diameters were evaluated in an optical interferometer used as a displacement sensor. The fibers were vibrated at a predetermined frequency and acceleration. HeNe and solid state lasers, LED, and white light were used as light sources. The fiber noise is shown to depend on the coherence properties of the light source used in the optical sensor. Dramatic noise reduction was demonstrated when employing low coherence light sources.
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© 1982 Laser Institute of America.
1982
Laser Institute of America
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