Fiber-optic ring interferometer with a multimode waveguide

The nature of propagation of electromagnetic oscillations in a multimode waveguide is considered and it is shown in principle that such a waveguide can be used in a fiber-optic ring interferometer in combination with an optical radiation source characterized by a short coherence length. A description is given of the apparatus and the results of an experimental investigation of such an interferometer are reported. Ways of improving further the sensitivity of this interferometer are discussed.