Does the EDFA still have power output when there is no input signal? Can it be used as a broadband light source?

Question: Does the EDFA still have power output when there is no input signal? Can it be used as a broadband light source?

Answer: Some modelsEDFA products (PA type, BA type with power below 27dBm, and LA type) have no input power starting threshold, that is, no matter how low the input signal power is, or even the input optical power is zero, the EDFA can be started, and it can be operated according to the pump driving current or output power set by the user. At this time, the output light is spontaneous emission of the EDFA itself, which is a normal phenomenon. Some customers use this output light to replace ASE broadband light source, which is a non-standard use. Long-term use may damage the EDFA itself, so it is not recommended to use it in this way. Users are recommended to standardize the use of EDFA according to the rated input power on the EDFA product test list.