Picosecond programmable laser sweepingover 50 mega-wavelengths per second

摘要

We report here the successful realization of 25 millions wavelengths per second using an SOA based PL around 1565 nm at a 75 MHz repetition rate. The laser is simply composed of an SOA, a CFBG (10 ps/nm) with a 100 nm bandwidth, an optical circulator, an EOM (intensity modulator), and an output coupler (20%). Pulse duration is around 45 ps and OSNR of the pulse is around 35 dB at 1565 nm without sweeping. Tunable dispersion compensating module (TDCM) was used to compress the chirped pulse output and 10 ps pulse duration was obtained at 1548 nm. Finally 25 mega-wavelengths per second was realized with under 3 pulses per wavelength and 1024 discrete wavelengths. Linear k-space sweeping function was enabled in the swept-source OCT (SS-OCT) system through graphical user interface (GUI).