J. Canning et Alg. Carter, MODAL INTERFEROMETER FOR IN-SITU MEASUREMENTS OF INDUCED CORE INDEX CHANGE IN OPTICAL FIBERS, Optics letters, 22(8), 1997, pp. 561-563
A simple interferometer based on modal interference is described. With
out compromising interferometer stability it is possible to measure in
dex changes of less than 1 x 10(-6). (C) 1997 Optical Society of Ameri
ca.