Fig. 1. Experimental setup of spectrally flat MIR-SC source. EYDFA, erbium–ytterbium-doped fiber amplifier; SMF, single-mode fiber; LD, laser diode; SM-TDF, single-mode thulium-doped fiber; MFA, mode field adapter; GCF, germania-core fiber; DM, dichroic mirror; HDZF, holmium-doped ZBLAN fiber; CMS, cladding-mode stripper; SC, supercontinuum.

Fig. 2. Spectra comparison for different positions.

Fig. 3. (a) Evolution of SC spectra against launched pump power at 40 kHz; (b) SC spectra comparison under different PRRs at pump power of 5.91 W.

Fig. 4. SC average output power as a function of the launched pump power under different pulse repetition rates with pulse duration of 1.6 ns.

Fig. 5. Power ratio beyond 3 μm under PRR of 40, 50, and 100 kHz.

Table 1. Specifications for the Used Fibers