Optical transmitter and control method of tunable optical filter

Abstract

An optical transmitter includes an optical modulator, a tunable optical filter, a temperature sensor, and a processor. The tunable optical filter is provided on an output side of the optical modulator and transmits light of a frequency corresponding to a control voltage. The temperature sensor detects a temperature around the tunable optical filter. The processor detects an optical loss occurring in the tunable optical filter, calculates a width of a range of the control voltage in which the detected optical loss is smaller than a specified threshold, adjusts the control voltage based on the temperature detected by the temperature sensor, and shifts the control voltage by a specified amount that is larger than zero and smaller than or equal to a half of the calculated width of the range when the optical loss is larger than or equal to the threshold.

Dependencies are inferred from the claim text.