Measurement of high-intensity focused ultrasound fields using miniaturized all-silica fiber-optic Fabry-Perot hydrophones

High-intensity focused ultrasounds (HIFUs), as a novel non-invasive surgery technology, have been used effectively for cancer therapy. In order to ensure the HIFU treatment safety, the acoustic pressure distributions and the size of the focal regions of HIFU fields need to be measured accurately. In this paper, the lateral sensitive and tip-sensitive all-silica fiberoptic Fabry–Perot ultrasonic hydrophone systems and the corresponding experimental setups are established to measure HIFU fields, respectively. The acoustic pressure distributions of the HIFU field along the X-axis, Y-axis, and Z-axis are compared in the degassed water by the lateral sensitive and tip-sensitive fiber-optic Fabry-Perot ultrasonic hydrophones. Experimental results show that the tip-sensitive configuration can measure the acoustic pressure distribution in the focal region with high accuracy than the lateral-sensitive configuration.