Accurate measurement of the cutoff wavelength in a microstructured optical fiber by means of an azimuthal filtering technique
Résumé
A simple self-referenced nondestructive method is proposed for measuring the cutoff wavelength of microstructured optical fibers (MOFs). It is based on the analysis of the time-dependent optical power transmitted through a bow-tie slit rotating in the far-field pattern of the fiber under test. As a first demonstration, the cutoff wavelength of a 2 m MOF sample is found to be close to that provided by numerical predictions (∼25 nm higher). Because of the high dynamics of the measurement, the uncertainty is limited to Δ λ ±10 nm.