Fig. 1. Experimental setup. (a) Er-doped fiber oscillator; (b) amplification and narrowband filtering at 1580 nm; (c) supercontinuum generation and spatial filtering; (d) sum-frequency generation; (e) digital storage oscilloscope and spectrum analyzer

Fig. 2. Spectra .(a) Spectra in three cases; (b) spectrum before HNLF; (c) measured and simulated spectra after HNLF; (d) wavelength tuning range and power of seed light

Fig. 3. Spectrum region selection and stability analysis. (a) Spectrum at 1030 nm is flat; (b) spectrum at 1030 nm is steep; (c) electrical pulse trace of 1030 nm optical signal at flat position of supercontinuum recorded by oscilloscope; (d) electrical pulse trace of 1030 nm optical signal at steep position of supercontinuum recorded by oscilloscope; (e) electrical pulse amplitude distribution of 1030 nm optical signal at flat position of supercontinuum; (f) electrical pulse amplitude distribution of 1

Fig. 4. Stability measurement. (a) Measured power of seed light with central wavelength of 1580 nm within 30 min; (b) measured power of seed light with central wavelength of 1030 nm at flat position of supercontinuum within 30 min; (c) measured power of seed light with central wavelength of 1030 nm at steep position of supercontinuum within 30 min; (d) relationship between theoretical intensity noise and optical power; (e) measured relative intensity noise value of pulses; (f) cross-correlation trace of