Coordinate Calibration Strategies for Photoacoustic Computed Tomography Without Prior Knowledge of Point Source Coordinates

In photoacoustic computed tomography, images are reconstructed through mathematical models. In this process, accurate coordinate positioning of the transducer is one of the key factors determining the imaging quality. However, due to processing errors, geometric calibration of the transducer becomes an indispensable step. To solve this problem, we utilized a geometric calibration scheme based on coordinate system translation, explained the specific reasons why point source coordinates are not needed as prior information, overcame the difficulties in accurately obtaining point source coordinates and coordinate system mismatch, and compared the accuracy of the two schemes (requiring point source coordinate priors vs. not requiring point source coordinate priors) in detail through K-Wave simulation of transducer arrays. Additionally, we demonstrate the versatility of our approach by simulating various transducer array shapes, showing its broad applicability. The image quality was significantly improved when the calibrated coordinates were used to reconstruct the image.