PM Mode Field Adapter (MFA)

Firsol polarization-maintaining (PM) mode field adapters provide low-loss fundamental-mode coupling between PM fibers with different mode field diameters, core diameters, or numerical apertures while maintaining polarization alignment. Available for 1.0, 1.5, and 2.0 μm fiber laser and amplifier systems, they support forward and backward transmission, CW optical power handling up to 100 W, and custom fiber combinations. For directional identification, we define transmission from the fiber with the smaller MFD to the fiber with the larger MFD as the forward direction, and transmission from the larger-MFD fiber to the smaller-MFD fiber as the backward direction.