Accurate modal characterization of passive components based on selective excitation of optical fibers

Modal performances of multimode optical passive components are measured by use of a selective excitation techique. Pure LPm1 modes up to LP15 1 mode are generated in a Ti: sapphire laser cavity and launched in the input fiber of the component under test. Azimuthal dependency of the LP11 mode excitation coefficient is used in an accurate centering technique of monomode and multimode splices or connectors.