Experimental study of transmission of ultrasonic wave in optical fibers

Optical waveguides are commonly used to transmit
electromagnetic radiation. The possibility of acoustic wave propagation in
optical waveguides creates new prospects for simultaneous transmission of laser
beam and ultrasonic wave. The measurements of the transmission of ultrasound in
optical waveguides were performed for three representative types of optical
fiber: a multimode step refractive index, a single-mode step refractive index
and a multimode graded refractive index. Amplitude characteristics of signal
propagated in optical waveguides of the three types of optical waveguides are
given in this paper. The frequencies, for which amplitude maxima were obtained,
overlapped resonant frequencies of a thick vibrating piezoelectric disk, which
was the source of the ultrasonic waves.