超短脉冲微波高效激发的高分辨率热声成像  

Unltrshort Pulsed Microwave Induced High-efficiency and High-resolution Thermoacoustic Imaging

作　　者：娄存广[1] 计钟[1] 丁文正[1] 

机构地区：[1]华南师范大学生物光子学研究院激光生命科学研究所,暨激光生命科学教育部重点实验室,广东广州510631

出　　处：《激光生物学报》2013年第1期48-52,共5页Acta Laser Biology Sinica

基　　金：科技部国家重点基础研究973计划项目(2011CB910402;2010CB732602);教育部"长江学者与创新团队计划"创新团队项目(IRT0829);国家自然科学基金项目(81127004;11104087)资助

摘　　要：微波热声成像综合了微波成像和超声成像的优点,具有很好的穿透深度及较高的图像分辨率。热声成像的激发源通常为基于脉冲调制的亚微秒级脉冲微波,激发能量密度约为几mJ/cm2,激发出的热声信号主频通常为2 MHz,成像分辨率约为500μm。随着热声成像向着临床应用方向发展,能否有效的减小辐射剂量并提高成像分辨率,是热声成像系统设计成败的一个关键因素。为了有效改善微波热声成像中热损伤及分辨率,设计开发了超短脉冲微波热声成像系统,实验结果表明该系统提高了热声转化效率约两个数量级,成像分辨率达到105μm,为热声成像的临床应用铺平了道路。Pulsed microwave induced thermoaeoustic imaging takes advantage of the depth penetration of microwave en ergy and the resolution of acoustic waves. The microwave source generally employed in thennoacoustic imaging has a pulse width of submicrosecond, with the energy density of several mJ/cm2. The excited thermoacoustic wave has a main frequency of 2 MHz, and a resolution of 500 μm can be obtained. With the development of thermoacoustic imaging to ward clinical application, it is very important to effectively reduce the radiation dose and improve the imaging resolution, which is a key factor for the successful application of thermoacoustic imaging system. In this paper, we designed a ultra short microwave induced thermoacoustic imaging system, the experimental results show that this system can improve the generation efficiency of thermoacoustic waves with two orders of magnitude, and the resolution can approximately reach up to about 100 μm.

关 键 词：热声成像 脉冲微波 转化效率 分辨率 

分 类 号：TN241[电子电信—物理电子学]