A novel photoacoustic tomography based on a time-resolved technique and an acoustic lens imaging system

A novel photoacoustic (PA) tomographic method, which is based on a time-resolved technique and an acoustic lens imaging system, is presented in this paper. A YAG laser operating at 532 nm with a 7 ns pulse width and 10 mJ optical pulse is employed as the excitation source to irradiate the tissue. PA signals generated from the tissue are imaged onto a multi-element linear array transducer with an acoustic lens. A 64 electronic switch is efficiently used for changing the parallel PA signals into a series. The proposed method directly provides PA images without any complex reconstruction algorithms. With the time-resolved technique, tomographic imaging can be achieved successfully. The results show that the images agree well with the original samples.