Tunable femtosecond near-infrared source based on a Yb:LYSO-laser-pumped optical parametric oscillator
Tian Wen-Long1, Wang Zhao-Hua2, †, , Zhu Jiang-Feng1, Wei Zhi-Yi2, ‡,
       

Measured beam quality factor (M2) of the SHG signal by the laser beam propagation analyzer. Insert: the typical CCD photograph of the transverse mode in far field.