Phase shift plus interpolation based photoacoustic imaging in layered media

Abstract

Photoacoustic imaging, an imaging method combining optical and ultrasound technologies, possesses advantages like high resolution, deep penetration, and non-invasiveness, thus finding wide application in the biomedical field. To achieve photoacoustic imaging of deep tissue, acoustic-resolution photoacoustic microscopy typically uses reconstruction algorithms to correct raw signals. However, currently used reconstruction algorithms commonly have requirements for the measured medium, resulting in poor imaging quality when the medium is irregularly layered. In this paper, the phase shift interpolation method is used to achieve photoacoustic imaging in irregularly layered media. This method extrapolates the wave field based on reference velocities selected from the actual sound velocity distribution, and then interpolates the reference wave field to obtain the actual wave field. Simulation and experimental results demonstrate that phase shift interpolation can achieve high-quality imaging in irregularly layered media.