Thorlabs offers an extensive selection of laser systems and individual laser diodes for telecom and datacom applications. Our tunable options include benchtop sources with tuning ranges in the C-band (1528 nm - 1566 nm) or L-band (1570 nm - 1609 nm), and rack-mounted sources with tuning ranges in the O-band (1250 nm - 1350 nm) or C+L band (1520 nm - 1630 nm). Single- and multi-channel fixed-wavelength sources include options at 850 nm, 1310 nm, and 1550 nm. We also offer a variety of single-frequency laser diodes, including Distributed Feedback (DFB) Lasers, External Cavity Lasers (ECL), and Ultra-Low-Noise (ULN) Lasers, which use a hybrid design that incorporates a single angled-facet gain chip coupled to an exceptionally long fiber Bragg grating.