Enhanced resolution optoacoustic microscopy using a picosecond high repetition rate Q-switched microchip laser
29 November 2022
New journal paper published in Journal of Biomedical Optics!
Gianni Nteroli, Giulia Messa, Manoj K. Dasa, Antti Penttinen, Antti Härkönen, Mircea Guina, Adrian Podoleanu, Stella Koutsikou, and Adrian Bradu
“Enhanced resolution optoacoustic microscopy using a picosecond high repetition rate Q-switched microchip laser,” Journal of Biomedical Optics 27(11), 110501 (2022).
Conventional optoacoustic microscopy (OAM) instruments have at their core a nanosecond pulse duration laser. If lasers with a shorter pulse duration are used, broader, higher frequency ultrasound waves are expected to be generated and as a result, the axial resolution of the instrument is improved. Here, we exploit the advantage offered by a picosecond duration pulse laser to enhance the axial resolution of an OAM instrument. In comparison to an instrument equipped with a 2-ns pulse duration laser, an improvement in the axial resolution of 50% is experimentally demonstrated by using excitation pulses of only 85 ps. To illustrate the capability of the instrument to generate high-quality optoacoustic images, en-face, in-vivo images of the brain of Xenopus laevis tadpole are presented with a lateral resolution of 3.8 μm throughout the entire axial imaging range.