The classical coherence formalism and guided-mode field representation is used to discuss the operation of few-mode fiber waveguide excited by a low-coherence, cross-spectrally pure, spatially coherent source in Michelson interferometer configuration as a sensor, even if a suppressed interference pattern at its exit face exists. In the case of a low- coherence excitation of few-mode fiber waveguide the principle of coherence modulation can be used, that is, the optical path difference between guided modes that exceeds the source coherence length can be compensated in Michelson interferometer configuration. The analysis of temporal coherence in a particular case of two-mode, weakly-guiding, step-index fiber waveguide takes also into consideration the effect of second-order modal dispersion; the potential applications to low- coherence source based interferometric sensors are discussed.

Date Published: 30 November 1994
PDF: 10 pages
Proc. SPIE 2341, Interferometry '94: Interferometric Fiber Sensing, (30 November 1994); doi: 10.1117/12.195542

Published in SPIE Proceedings Vol. 2341:
Interferometry '94: Interferometric Fiber Sensing
Eric Udd; Ralph P. Tatam, Editor(s)