A fiber optic vibration sensor is disclosed. This invention has an optical
fiber of a tubular configuration that includes a cladding layer and a
core, having a first end, a second end and a sensing region; a source of
laser for emitting laser onto the first end of the optical fiber; an
optical diode connected to the second end of the optical fiber; and an
optical wave analyzer connected to the optical diode; wherein the sensing
region includes at least a polished region formed by polishing a side of
the optical fiber and a grating disposed in the polishing region.