ABSTRACT
Photoacoustic tomography, which is a newborn non-invasive medical imaging method combined the high contrast of pure optical imaging and high imaging depth of ultrasound imaging (Wang, Pang, Ku, Xie, Stoica, Wang, 2003), works based on the initial temperature rise caused by bio-tissues absorption of short duration-time (nanosecond magnitude) pulse laser energy. The temperature rise will cause thermal expansion in bio-tissues and thus elastic waves penetrating through bio-tissues, which is known as photoacoustic signals. By detecting these signals around the imaging target and proceeding them with appropriate reconstruction arithmetic, images of laser energy absorption inside bio-tissues can then be obtained (Yang, Xing, Gu, Tan, Zeng, 2005).
