Thorlabs offers a varied selection of single mode (SM), polarization-maintaining (PM), multimode (MM), and double-clad fiber couplers, as well as single mode 1x8 and 1x16 PLC waveguide splitters, wideband multimode circulators, RGB combiners, and WDMs. Our SM and double-clad fiber coupler offerings also include a selection of components ideal for OCT applications.