| 摘要 |
PROBLEM TO BE SOLVED: To provide a wavelength variable type semiconductor laser element easily controlling current and increasing a speed in switching wavelength.SOLUTION: The semiconductor laser element 1A is equipped with: a DFB region 10 having a wavelength-reflection rate characteristic cyclically changing with a first wavelength interval and generating light due to current injection; and a DBR region 20 provided on a semiconductor substrate 3 side by side with the DFB region 10 and having a wavelength-reflection rate characteristic cyclically changing with a second wavelength interval different from the first wavelength interval. In the DFB region 10, a gain waveguide 11 generating light by current injection, and a refractive index variable waveguide 12 having a refractive index changing owing to current injection and having a diffraction grating 121a formed thereon, are alternately provided, and current is injected to the waveguides independently. The DBR region 20 has: a refractive index changing layer 201 having a refractive index changing due to current injection; and an SSG structure 202a. |
