Portable all-fiber dual-output widely tunable light source for coherent Raman imaging

Biomed Opt Express. 2019 Aug 5;10(9):4437-4449. doi: 10.1364/BOE.10.004437. eCollection 2019 Sep 1.

Abstract

We present a rapidly tunable dual-output all-fiber light source for coherent Raman imaging, based on a dispersively matched mode-locked laser pumping a parametric oscillator. Output pump and Stokes pulses with a maximal power of 170 and 400 mW, respectively, and equal durations of 7 ps could be generated. The tuning mechanism required no mechanical delay line, enabling all-electronic arbitrary wavelength switching across more than 2700 cm - 1 in less than 5 ms. The compact setup showed a reliable operation despite mechanical shocks of more than 25 m / s 2 and is, thus, well suited for operation in a mobile cart. Imaging mouse and human skin tissue with both the portable light source and a commercial laboratory-bound reference system yielded qualitatively equal results and verified the portable light source being well suited for coherent Raman microscopy.