The PSC Single Mode Couplers (Splitters) are based on BTF technology. PSC SM couplers offer very low insertion loss, low polarization dependence and excellent enviromental stability. Accurate coupling ratio from 50/50 to 1/99 are available with very tight uniformity in a wide wavelength range. The SM fiber couplers/splitters find extensive application to perform power splitting and mornitoring fuctions for many types of communication systems, general purpose in SM fiber pigtailed systems, or FBG sensor interrogation systems.