Fiber optic circulators rely on non‑reciprocal optical principles, typically using a combination of polarisation optics, Faraday rotators, and beam splitters. These components manipulate the polarisation state of light so that it follows a fixed directional path regardless of the. An optical circulator is a three- or four-port optical device designed such that light entering any port exits from the next. Unlike optical isolators that block reflected light, a circulator routes optical signals in a specific order — typically Port 1 → Port 2 and Port 2 →. Circulators are integrated into Optical Amplifiers, such as Erbium-Doped Fiber Amplifiers (EDFAs), where they manage the high-power pump light required for signal boosting. For example: This. Fiber optic circulators act as signal routers, transmitting light from an input fiber to an output fiber, but directing light that returns along that output fiber to a third port.
