A nondestructive method is proposed for evaluating power coupling coefficients at directional couplers contained in an optical integrated circuit. This technique, which is based on optical heterodyne interferometry, makes it possible to obtain individual coupler element information without removing the element from the optical circuit. General N-channel waveguide coupling characteristics are analyzed, and they are experimentally evaluated for two-and four-channel waveguides that have been practically designed as frequency multi/demultiplexers operating in the 1.55-μm-wavelength region.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics