| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of controlling a tunable semiconductor laser capable of stably controlling an oscillation wavelength to a target wavelength.SOLUTION: There is provided a method of controlling a tunable semiconductor laser comprising a CSG-DBR region 22 and an SG-DFB region 24 as a first wavelength selection part and a second wavelength selection part, respectively. The method comprises a first control step forming a first return loop L1 of detecting a difference between a target oscillation wavelength and a current oscillation wavelength; and a second control step forming a second return loop L2 of calculating a differential power amount which compensates for the difference of each of a plurality of heaters 28 provided in the CSG-DBR region 22 and the SG-DFB region 24, and setting a value obtained by adding the differential power amount to an initial power amount as a target amount of power to be supplied to each of the heaters 28. |
