Tunable optical filter or reflector

摘要

A tunable optical fiber filter or reflector is composed of a single-mode optical fiber having UV-induced fiber gratings in its core region. A planar surface is formed by a mechanical polishing technique such that the planar surface is contiguous to the core region of the optical fiber. The planar surface is covered with a material having a refractive index close to the refractive index of the optical fiber. As the refractive index of the material is changed, the tuning of the reflection or transmission spectra of the optical fiber filter or reflector is attained. The tunable optical fiber filter or reflector is used in optical communication systems, sensoring systems, or as external cavities of lasers.