| 摘要 |
PURPOSE:To make wavelength tuning possible, by controlling the injection current of a phase controlling part by applying a control electrode, and changing the reflection index corresponding to the carrier density in a resonators. CONSTITUTION:In the main body 6 of this semiconductor laser, phase control is performed by changing the stripe width of a resonator 1. In a phase controlling part, current injection is enabled independently from other parts by means of a control electrode 2. The reflection index of the phase controlling part changes according to the density of injected carrier, and the available range of phase shift is about 0-pi. Thereby, the oscillation wavelength can be controlled within the stop bandwidth determined by a coupling constant (kappa) of DFB type laser, so that the variable range of oscillation wavelength is widened and wavelength tuning of wide band is enabled. |
