Optical attenuators

Attenuators are passive devices used in optical networks or laboratory tests to set the appropriate signal levels. They are used to prevent overdriving and damage to the receiver diodes.

A distinction is made between adapter-type and in-line attenuators, including fixed and variable types.

In-line type attenuators can be mostly understood as a jumper cable with a given attenuation.

The adapter type is constructed as a combination of a connector and an adapter, as it can be plugged into an adapter and connected to another connector. Both fixed and tunable attenuators can be of hybrid design.

Fixed attenuators usually cover a range of 0-25 dB in 1 dB steps. The attenuation value is obtained by using an optical fibre with an appropriate length of attenuation within the attenuator.

Variable adaptor type attenuators mostly cover the range 0,3-25 dB by varying the size of the air gap, but it should be borne in mind that their reflection attenuation is not as good due to the air gap.