Patent ID: 9252558
Filing Date: 2016-02-02
CPC Classification: H01S,H04B

Claim Text:
1. An optical amplifier comprising: an optical amplification medium; a pump light generator configured to generate pump light with a power corresponding to a set control value and supply the generated pump light to the optical amplification medium; a first controller including a level control circuit configured to generate the control value such that an output power of the optical amplification medium approaches a target power, and a limiter configured to limit a range of the control value; a latch circuit configured to set a specific control value to the pump light generator during a period in which the first controller is in a stop state; a limiter controller configured to control the limiter, when the first controller is restarted, so that the limiter limits the control value such that an upper limit value of the control value is set to be smaller than a value used before the first controller was stopped, and control the limiter, when the first controller is restarted, so that the limiter limits the control value such that a lower limit value of the control value is set to be higher than a value used before the first controller was stopped.