| 摘要 |
Provided is a wavelength-variable laser including an SOA which controls not a shape of a gain spectrum itself in the SOA but a shape of a gain spectrum obtained in the entire SOA to enable inhibition of output fluctuations. The wavelength-variable laser including an SOA includes: a wavelength selection mechanism for selectively reflecting a wavelength; an SOA for amplifying light, the SOA being configured to reflect light that enters a first end facet by a second end facet opposite to the first facet and to cause light amplified in an active layer to exit from the first facet; and a reflecting member provided outside the SOA, the reflecting member forming a resonator in a pair with the second facet, in which the second facet has a multilayer film to control of a shape of gain spectrum obtained in the entire SOA, the multilayer film having a reflectance depending on wavelength. |
