Abstract
In this report, a method of measuring intense ultrasound field using a fiber optic probe is studied. We try to utilize the modulation of optical reflectivity at the end of the optical fiber through a change in the refractive index of air due to sound pressure. The theoretical sensitivity for air is studied and a setup for the measurement is described. Comparisons with a commercial probe-type condenser microphone are performed. The absolute value of sound pressure estimated theoretically almost agreed with the results obtained using a conventional microphone and showed good linearity. The validity of the method was proved using three measurement examples.