This paper presents the fundamental principles of the optical circulator, and goes on to report on development of a marketable 3-port optical circulator that achieves low loss by optimizing losses between the various ports. This means that if light enters port 1 it is emitted from port 2, but if some of the emitted light is reflected back to the circulator, it does not come out of port 1 but. The optical circulator is a fundamental device, acting as an advanced traffic controller that provides strict directional control over light signals within the network architecture. These non-reciprocal devices route light from one port to another in a unidirectional manner, ensuring efficient signal transmission and reception.
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