do you know what an optical isolator is

An optical isolator is a passive optical device that allows only one-way light to pass through, and its working principle is based on the non-reciprocity of Faraday rotation. The light reflected back by the fiber can be well isolated by the optical isolator.

Optical isolators mainly use the Faraday effect of magneto-optical crystals. The characteristics of optical isolators are: low forward insertion loss, high reverse isolation, and high return loss. An optical isolator is a passive device that allows light to pass in one direction and prevents it from passing in the opposite direction. Its function is to limit the direction of light so that light can only be transmitted in one direction. Good isolation, improve light wave transmission efficiency.

It is also a dual-port optical device with non-reciprocal properties. It has little attenuation to the optical signal transmitted in the forward direction and great attenuation to the optical signal transmitted in the opposite direction, forming a one-way path of light. An optical isolator is connected between the laser and the transmission fiber, which can effectively suppress the reflected light generated from the distal end face of the fiber, the interface of the fiber connector, etc. from returning to the laser, so as to ensure the stability of the laser working state and reduce the system caused by reflected light. noise. This is even more important for high-speed optical fiber communication coherent optical fiber communication systems.