Department of Electronic and Electrical Engineering;
the Southern University of Science and Technology;
Shenzhen 518055;
China;
Department of Electronic Engineering;
The Chinese University of Hong Kong;
Hong Kong 999077;
China;
Shenzhen Research Institute of The Chinese University of Hong Kong in Shenzhen;
Shenzhen 518172;
China;
photoacoustic tomography; dual transducers; image enhancement; signal responding range;