Photoacoustic Tomography using a Michelson Interferometer with Quadrature Phase Detection

TL;DR

This paper introduces a Michelson interferometer-based pressure sensor with quadrature phase detection for photoacoustic tomography, enabling rapid full surface detection suitable for clinical use.

Contribution

It demonstrates a novel interferometer sensor with quadrature phase detection that allows quick, full-surface measurements without retuning, advancing photoacoustic imaging technology.

Findings

Achieved sub-millimeter resolution in phantom imaging

Validated detector sensitivity with theoretical and experimental data

Enabled rapid full surface detection for clinical applications

Abstract

We present a pressure sensor based on a Michelson interferometer, for use in photoacoustic tomography. Quadrature phase detection is employed allowing measurement at any point on the mirror surface without having to retune the interferometer, as is typically required by Fabry-Perot type detectors. This opens the door to rapid full surface detection, which is necessary for clinical applications. Theory relating acoustic pressure to detected acoustic particle displacements is used to calculate the detector sensitivity, which is validated with measurement. Proof-of-concept tomographic images of blood vessel phantoms have been taken with sub-millimeter resolution at depths of several millimeters.