OPTICAL TRANSMITTER AND CONTROL METHOD OF TUNABLE OPTICAL FILTER

Japanese Patent JP2022139531

A

To improve characteristics of an optical signal outputted from an optical transmitter provided with a tunable optical filter.SOLUTION: An optical transmitter 1 includes an optical modulator 13, a tunable optical filter 16, and photo detectors PD1, PD2, a width calculator 28a, a temperature sensor 17, an adjustment unit 28b, and a correction unit 28c. The tunable optical filter 16 is disposed on an output side of the optical modulator 13 and transmits light of a frequency corresponding to a control voltage. An optical loss which occurs in the tunable optical filter 16 is detected on the basis of monitored values of the photo detectors PD1, PD2. The width calculator 28a calculates a width of a range of the control voltage where the detected optical loss becomes smaller than a predetermined threshold value. The temperature sensor 17 detects a temperature around the tunable optical filter 16. The adjustment unit 28b adjusts the control voltage on the basis of the temperature detected by the temperature sensor 17. The correction unit 28c shifts the control voltage by only a specified amount within a range between larger than zero and smaller than or equal to a half of the width calculated by the width calculator 28a when the optical loss becomes larger than or equal to the threshold value.SELECTED DRAWING: Figure 1

TOMIOKA ITAI
YASUDA SHUICHI

JP2021039962A

September 26, 2022

March 12, 2021

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FUJITSU OPTICAL COMPONENTS LTD

H04B10/40; H04B10/079

Hiroyoshi Aoki
Masayuki Amada
Yoshiyuki Osuge

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