Measurement of propagation characteristics of an optical waveguide by disturbing its evanescent field with a NSOM probe

초록

Near-field Scanning Optical Microscope (NSOM) can measure the optical signal of an optical waveguide and its topography, simultaneously. In general, the propagation characteristics of waveguide devices have been measured by detecting directly the evanescent field with an optical fiber probe. But, it is not easy to get the optical signal with high S/R since the transmission efficiency of the fiber probe is very low due to its small aperture. In this study, we measured change in the output intensity of an optical waveguide device by disturbing the evanescent field between the core and the cladding of a waveguide optical with the fiber probe, and thus could estimate its propagation characteristics.