研究了一种基于光子晶体光纤参量振荡器的相干反斯托克斯拉曼散射(CARS)成像光源。该光源采用中心波长为1 030 nm的皮秒光纤激光器作为泵浦源,以无截止单模光子晶体光纤作为参量增益,通过搭建光参量振荡器,实现平均功率为10 mW的参量激光输出。在色散滤波效应的作用下,该光源输出波长可实现连续可调,调谐范围为782~793 nm,对应的波数覆盖范围为2 901~3 078 cm-1。该光源产生的两束激光脉冲可实现空间自同步、时间自重合,用于CARS成像测量时,无需空间、时间对准,有望推动CARS成像光源向全光纤化、小型化的方向发展。

A coherent anti-Stokes Raman scattering(CARS) spectral imaging light source is demonstrated based on a fiber optical parametric oscillator(FOPO).By using a picosecond fiber laser as the pump source and a piece of endless single-mode photonic crystal fiber as parametric gain,pulses with an average power of 10 mW are achieved.Thanks to the effect of dispersion filtering,the output wavelength of the light source can be continuously tuned with a tuning range of 782-793 nm,corresponding to a wave number of 2 901-3 078 cm-1.The residual pump pulses and the generated pulses are temporal self-synchronized and spatial overlapped,therefore additional synchronization and alignment are not needed for CARS applications.Based on these advantages,the presented FOPO may pave the way to real-world biomedical and clinic applications.