US 12,328,145 B2
Optical transmitter and control method of tunable optical filter
Takeyasu Tomioka, Sapporo (JP); and Shuichi Yasuda, Sapporo (JP)
Assigned to FUJITSU OPTICAL COMPONENTS LIMITED, Kawasaki (JP)
Filed by Fujitsu Optical Components Limited, Kawasaki (JP)
Filed on Jan. 20, 2022, as Appl. No. 17/580,234.
Claims priority of application No. 2021-039962 (JP), filed on Mar. 12, 2021.
Prior Publication US 2022/0294534 A1, Sep. 15, 2022
Int. Cl. H04B 10/54 (2013.01); H04B 10/572 (2013.01); H04B 10/69 (2013.01)
CPC H04B 10/54 (2013.01) [H04B 10/572 (2013.01); H04B 10/6911 (2013.01); H04B 10/697 (2013.01)] 6 Claims
OG exemplary drawing
 
1. An optical transmitter comprising:
an optical modulator;
a tunable optical filter provided on an output side of the optical modulator and configured to transmit light of a frequency corresponding to a control voltage;
a temperature sensor configured to detect a temperature around the tunable optical filter; and
a processor configured to
detect an optical loss occurring in the tunable optical filter,
calculate a width of a range of the control voltage in which the detected optical loss is smaller than a specified threshold,
adjust the control voltage based on the temperature detected by the temperature sensor, and
shift 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.