Here we present a Weighted Synthetic Aperture Focusing Technique (W-SAFT) as a universal framework that effectively accounts for the non-uniform distribution of both the excitation light field and spatial sensitivity field of the detector. As a result, W-SAFT maintains optical resolution performance at superficial depths while improving the acoustic resolving capacity for deeper tissues. The dynamic range of the optoacoustic data is compressed using a general fluence decay term applied to the W-SAFT operator, allowing a more uniform visualization of the entire imaged volume. Our three-dimensional algorithm makes use of the sample's surface to account for the heterogeneity produced when scanning a finite-size light beam. We tested a GPU implementation of W-SAFT with numerical simulations and showcase its performance on experimental data acquired from targets embedded in tissue mimicking phantoms. |
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