Last updated on 01/27/2023
An automatic light control (ALC) mode is a feature that can be used in an optical fiber amplifier to automatically adjust the gain of the amplifier to maintain a constant output power level. The ALC mode uses a feedback loop to monitor the output power level and adjust the pump power or attenuation of the fiber amplifier as needed to keep the output power level constant.
ALC mode is useful because it can help to ensure that the output power level is consistent even when the input power changes.
Additionally, ALC mode can help keep the output power consistent against variations in temperature or other environmental factors that can affect the performance of an optical fiber amplifier. ALC works to adjust the output power consistent to compensate for such variations. ALC is especially useful when an optical fiber amplifier needs to be operated at a constant output power level during day and at night.
In ACC mode, such compensation is not conducted, and the output power may change with temperature, even when the input power does not change.
In the long term, ALC mode can help keep the output power consistent against natural degradation (i.e. aging) of components inside.