Fig. 1. Scanning filter responsivity test system

Fig. 2. Experimental results. (a) Reference response bandwidth; (b) relative response curve when driving frequency from 800 Hz to 100 kHz

Fig. 3. Experimental system configuration of proposed FDML frequency-swept erbium-doped fiber laser

Fig. 4. Experimental results. (a) Output spectrum of FDML frequency-swept laser; (b) output spectrum of FDML frequency-swept laser at different peak-to-peak driving voltages of FFP-TF2

Fig. 5. Optical spectra of forward scan and backward scan of the FDML frequency-swept fiber laser

Fig. 6. Experimental results. (a) Laser backward scan optical spectra when frequency offset is +0 Hz and +6 Hz, respectively; relative intensity for forward and backward scans using (b) LDF and (c) SMF as delay fibers, respectively

Fig. 7. Experimental results. (a) Instantaneous normalized spectra of the FDML frequency-swept fiber laser using LDF and SMF as delay fibers, respectively; (b) laser spectrum at fixed laser wavelength of 1550 nm using LDF as delay fiber

Fig. 8. Experimental results. For forward scanning of the FDML fiber laser, measured instantaneous laser linewidths under driving frequency offset of (a) -3 Hz, (b) +0 Hz, and (c) +3 Hz, respectively; for backward scanning, measured instantaneous laser linewidths under driving frequency offset of (d) -3 Hz, (e) +0 Hz, and (f) +3 Hz, respectively (inset: measured for the frequency-swept laser output correspondingly using the maximum hold mode of the OSA)