Abstract
Fast functional photoacoustic microscopy requires multi-wavelength pulsed laser sources with high pulse repetition rates, short wavelength switching time, and sufficient pulse energies. Here, we report the development of a stimulated-Raman-scattering-based multi-wavelength pulsed laser source for fast functional photoacoustic imaging. The new laser source is pumped with a 532 nm 1 MHz pulsed laser. The 532 nm laser beam is split into two: one pumps a 5 m optical fiber to excite a 558 nm wavelength via stimulated Raman scattering; the other goes through a 50 m optical fiber to delay the 532 nm pulse by 220 ns. The two beams are combined and coupled into an optical fiber for photoacoustic excitation. As a result, the new laser source can generate 2 million pulses per second, switch wavelengths in 220 ns, and provide hundreds of nanojoules pulse energy for each wavelength. Using this laser source, we demonstrate optical-resolution photoacoustic imaging of microvascular structures and oxygen saturation in the mouse ear. The ultrashort wavelength switching time enables oxygen saturation imaging of flowing red blood cells, which is valuable for high-resolution functional imaging.
© 2017 Optical Society of America
Full Article | PDF ArticleMore Like This
Kevan L. Bell, Parsin Haji Reza, and Roger J. Zemp
Opt. Lett. 44(14) 3466-3469 (2019)
Yifeng Zhou, Fenghe Zhong, and Song Hu
Opt. Lett. 46(11) 2690-2693 (2021)
Dongfang Li, Yue Yao, Tianxiang Zuo, Jiaye Xu, Chao Tao, Xiaoqin Qian, and Xiaojun Liu
Opt. Lett. 48(21) 5711-5714 (2023)