Photolithography on optical fiber and micro-fabrication of fiber-optic devices controlling evanescent field

New photolithographic fabrications of micro fiber-optic devices for telecommunication are reported. A variable attenuator and a tunable filter have been designed based on an evanescent field interaction. The devices have been fabricated by applying surface and bulk micromachining to the optical fiber fixed on the Si substrate. Since the optical fiber is side-polished, the light wave interacts through evanescent field with micro Si structures fabricated on the optical fiber. The initial optical properties in light attenuation and wavelength dependent transmittance have been measured. The proposed fabrication technique will enable a new type of fiber optic devices in telecommunication.