为了研究不同扫描半径对光声成像的影响, 采用了有限扫描角度和滤波反投影算法, 得出了吸收体间的距离与探测器旋转扫描半径的比值越大, 则成像亮度差异明显, 反之则能较好的反映吸收体的光吸收分布, 但成像对比度又将下降。采用光声信号衰减补偿的方法, 并对前者重建图像取域值, 得到了较好的图像质量。该研究结果对光声成像旋转扫描半径的合理选择和成像效果评估具有较好的参考价值。

In order to study the influence of differential scanning radius on photoacoustic imaging, numerical experiments of limited-view scanning and filter back -projection algorithm are carried out. The results of simulations show that the lightness of images isdifferent when the ratio of absorbers’distance and scanning radius is increased. However it is contrary for decrease, but the contrastof images will be declined. The method of photoacoustic signal attenuation compensation was adopted; the good quality of imaging wasobtained when a thresholding was adapted to the former reconstructed imaging. The results of the study are helpful for the choice ofscanning radius and the evaluation of reconstructed images.