Patent ID: 11870208
Assignee: NEC CORPORATION
Field: Optics (Instruments)
Classification: CPC H  G | IPC H

Claim 7:
8. A control method for an optical fiber amplifier, comprising:
supplying pumping light from a light source to a clad in an optical fiber that is supplied with the pumping light, the optical fiber amplifying an optical signal, the optical fiber including a plurality of cores in the clad;
causing the pumping light to be combined with the optical signal;
collecting the pumping light that is supplied to the optical fiber but that is not absorbed by the optical fiber, without collecting the optical signal;
monitoring a modulation frequency component of the pumping light that has been collected and that has passed through the optical fiber;
controlling a state of the pumping light according to a monitoring result; and
modulating the pumping light at a frequency higher than a response time of the optical fiber.