Methods of modulation of light wave propagated in optical fiber using ultrasonic wave

AbstractGlass optical waveguides are a promising medium for mixed laser-ultrasonic applications. Initial analysis of the possibilities of compensating for the flaws associated with laser and ultrasonic technologies, e.g. in the process of cutting biological tissues, showed that such a mixed technology could be more effective. The measurements of ultrasonic wave transmission ware performed for three representative types of optical fibers: a multimode step-index fiber, a single mode step-index fiber and multimode gradient-index fiber. The material the optical fiber is made of enables simultaneous transmission of light and ultrasonic wave. This study presents amplitude characteristics of the measured output voltages of the capacitive sensor for the types of optical fibers in question. The work also presents methods of modulation of light wave propagated in optical fiber by means of ultrasonic wave, which is performed with the use of radial vibrations of piezoelectric disk and longitudinal vibrations generated by a sandwich ultrasonic transducer with a wave velocity transformer. Experiments were performed using a Mach-Zehnder interferometer