A triple window coupler is a type of optical fiber coupler that can split or combine optical signals. It’s used in fiber optics research, control rooms, testing equipment, and monitoring systems. How it works Triple window couplers are fused bi-conical taper couplers (FBT couplers) They have a variable coupling ratio that can range from 0–100% They can support wavelengths of 1310, 1490, and 1550 They have low insertion loss and high polarization isolation Other types of optical fiber couplers: Y couplers, T couplers, Star couplers, Tree couplers, WDM couplers, and Ratio couplers. Optical couplers Optical couplers are passive devices that manipulate light within fiber optic networks. They can split or combine optical signals, allowing for efficient communication. Coupling ratio The coupling ratio of a fiber optic coupler determines how much of the input optical power is coupled to each output port. Fiber optic coupler features Variable coupling ratio from 0–100, Low insertion loss, High polarization isolation, Available wavelengths include 1310 nm and 1550 nm, and PM and non-PM types available. Overview: A triple window coupler (TWC) is an optical fiber component that splits or combines optical signals between input and output fibers. It has multiple operating wavelengths and is used in fiber sensors, optical testing instruments, and compact optical modules.