A photoacoustic tomography imaging system using a low-coherence interferometer with rapid detection of phase modulation was designed, fabricated, and tested for biologic imaging. A noncontact probing technique was applied to improve the practicability of the system. The technique is experimentally verified by the image of a simulated tissue sample and the blood vessels within a mouse ear flap (pinna) in vivo. The system’s axial and lateral resolutions are evaluated at 45 and ~15 μm, respectively. The system’s imaging depth is 1mm in a special phantom. The results show that the system has the feasibility to be used as a photoacoustic tomography imaging method, and it may provide a kind of possibility of noncontact real-time PAT.
A simultaneous photoacoustic (PA) tomography imaging technique in multilayer samples was developed. Instead of using the PA image reconstruction methods on the basis of complex algorithms, obtaining a two-dimensional PA image in real time is available by using an acoustic lens that has the ability of parallel imaging. The imaging system can acquire the complete PA signals of high signal-to-noise ratio from all the object planes by utilizing the advantages of the acoustic lens with long focal depth and a fast data acquisition system with a high sampling rate. With the time-resolved technique, the PA signals from different object planes can be distinguished and then the high optical contrast multilayer PA images can be reconstructed simultaneously without any algorithms. The experimental results show that the reconstructed sections agree well with the original samples.