Two-Dimensional Photoacoustic Imaging of Blood Vessel Networks within Biological Tissues

Photoacoustic tomography （PAT） is a powerful imaging merits and most compelling features of light and sound, technique for medical diagnosis because it combines the We describe a PAT experimental system constructed in our laboratory which consists of a Q-switched Nd：YAG pulse laser operating at 532nm with a 8-ns pulse width to generate the photoacoustic signals from a biological sample. Two-dimensional photoacoustic imaging of blood vessel networks lcm below the tissue surface is achieved, We also successfully demonstrate that the system is capable of imaging the blood vessels over the ex vivo rat brain with skull and skin intact.     

时域光声谱技术及其在生物组织检测中的应用

当强度调制的光束照射于吸收物质,周期性热流使周围的介质热胀冷缩而激发声波,这种将光能转化为声能的现象称为光声效应。基于光声效应的时域光声谱技术将光学和声学有机地结合,为生物组织的无损检测技术提供了新的检测手段。该技术能够实现类似光学技术的高对比度和近似于声学技术的高精度和穿透深度,在生物医学检测中具有广阔的应用前景。文章介绍时域光声谱技术的原理及其在生物组织成分检测和层析成像检测中的应用。     

透射光偏振度与散射次数关系的研究

偏振态与散射次数的关系对于提取深入组织内部的后向散射光有很重要的价值.本文分析了透射光的偏振度与光在介质中的散射次数的关系，给出了偏振光完全失去偏振态所需的散射次数，并用直接散射的实验方法进行了验证，得出当散射次数为14次时偏振光将失去其偏振特性的结论.