Portable optical-resolution photoacoustic microscopy with a pulsed laser diode excitation

Optical-resolution photoacoustic microscopy (OR-PAM) has been significantly improved in terms of spatial resolution, detection sensitivity, imaging speed, and penetration depth. However, the popular producibility of OR-PAM system is still limited by the size and cost of solid-state laser excitation. Here, we developed a portable laser-diode-based OR-PAM (LD-OR-PAM) system using a pulsed semiconductor laser source, which was operated at 905 +/- 615 nm with a pulse energy as low as 4.9 mu J. The measured lateral resolution has been improved to similar to 1.5 mu m from hundreds of microns. The compact and inexpensive natures of LD-OR-PAM would promote the potential clinical applications such as in dermatology. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4791566]