Time-resolved quantitative multiphase interferometric imaging of a highly focused ultrasound pulse

TL;DR

This paper demonstrates that multiphase interferometric imaging can quantitatively capture high-resolution, time-resolved profiles of a focused ultrasound pulse, validated by comparison with fiber-optic hydrophone measurements.

Contribution

It introduces a multiphase acquisition approach for interferometric imaging of repetitive transient phenomena, enabling accurate quantitative measurements of high-frequency ultrasound fields.

Findings

High-resolution sound field profiles obtained

Pressure measurements agree with hydrophone data

Multiphase imaging enhances transient phenomena analysis

Abstract

Interferometric imaging is a well established method to image phase objects by mixing the image wavefront with a reference one on a CCD camera. It has also been applied to fast transient phenomena, mostly through the analysis of single interferograms. It is shown that for repetitive phenomena multiphase acquisition brings significant advantages. A 1 MHz focused sound field emitted by a hemispherical piezotransducer in water is imaged as an example. Quantitative image analysis provides high resolution sound field profiles. Pressure at focus determined by this method agrees with measurements from a fiber-optic probe hydrophone. This confirms that multiphase interferometric imaging can indeed provide quantitative measurements.