| 摘要 |
PROBLEM TO BE SOLVED: To provide a wavelength variable laser with an SOA capable of suppressing variation in the optical output of laser, by not controlling the shape of a gain spectrum of SOA itself but controlling the shape of a gain spectrum obtained in the whole SOA.SOLUTION: The wavelength variable laser with an SOA includes: a wavelength selection mechanism which selects and reflects a wavelength; an SOA, i.e., a semiconductor optical amplifier for amplifying the light, configured to reflect the incident light from a first end face on a second end face on the reverse side of the first end face, and to emit light amplified by an active layer from the first end face side; and a reflection member provided on the outside of the SOA and paired with the second end face reflecting the incident light so as to form a resonator. On the second end face in the SOA on the light reflecting side, a multilayer film having a wavelength-dependent reflectance is formed and configured so that the shape of a gain spectrum obtained in the whole SOA can be controlled. |
