本文提出了一种提高微波热声断层成像层析能力的方法和装置.基于热声成像原理和声聚焦理论,搭建了由超短脉冲微波源、384阵元环形探测器、声聚焦透镜、384-64通道采集切换系统、精密扫描位移平台构成的微波热声三维成像系统,并实现了模拟样品的断层成像.实验结果表明该系统能够实现亚毫米级分辨率的热声成像,通过声聚焦方法成倍地提高了其层析分辨率.这对推动微波热声CT技术走向临床具有重要的意义.
In this paper, a method and a device to improve the tomographic resolution of thermoacoustic computed tomography (CT) was introduced. Based on the principle of thermoacoustie imaging and the theory of acoustic focusing, thermoacoustic CT system was constructed, which consists of a pulsed microwave source, a 384 elements ring-detector, acoustic focusing lens, aseanning platform, and adata acquisition system with 384-64 channels switching system, Ther- moacoustic imaging of a phantom sample was achieved. The results show that this system can not only obtain the tomo- graphy imaging with sub-millimeter resolution, but also efficiently improve the tomographic resolution by acoustic focu- sing, which are significant to further push the microwave-induced thermocoustic CT system to forward clinical applica- tion.