Fig. 1. Experimental setup. (a) Er oscillator; (b) Er-doped fiber amplifier 1; (c) divided pulse amplifier; (d) second harmonic generation; (e) Er-doped fiber amplifier 2; (f) Yb oscillator; (g) Yb-doped fiber amplifier and master oscillator power amplifier; (h) microscope

Fig. 2. Spectra and pulse widths. (a) Output spectra of EDFL; (b) autocorrelation traces of pump light; (c) output spectra of YDFL; (d) autocorrelation traces of Stokes light

Fig. 3. Experimental results. (a) Frequency-doubling light spectrum and autocorrelation traces; (b) beam profile and M² measurement result of frequency-doubling light; (c) variation of the repetition rate of the slave laser with the mismatch of cavity length; (d) CARS image of subcutaneous adipose tissue in mouse ears at 3156 cm^-1