Optical isolator

Optical component allowing the transmission of light in only one direction

An optical isolator, or optical diode, is an optical component which allows the transmission of light in only one direction. It is typically used to prevent unwanted feedback into an optical oscillator, such as a laser cavity. The operation of conventional optical isolators relies on the Faraday effect (which in turn is produced by magneto-optic effect), which is used in the main component, the Faraday rotator.

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