| 摘要 |
PURPOSE:To obtain frequency control extending over a wide range and FM characteristics at high speed simultaneously by biassing a distributed Bragg reflection section in the forward direction capable of injecting carriers, biassing at least one part of a phase control section in the opposite direction and controlling an effective refractive index by an electro-optic effect. CONSTITUTION:A DBR section 30 is biassed in the forward direction and an effective refractive index can be controlled by injecting carriers while a phase control section 20 is reverse-biassed, the phase of beams propagated through an active section 10 is changed effectively by the alteration of the effective refractive index by an electro- optic effect, and the oscillation frequency of the beams can be varied. The change of the effective refractive index at that time is made smaller than the case of carrier injection by approximately two figures while response characteristics up to high frequency are acquired when the voltage of the active section 10 is modulated and oscillation frequency is modulated. Accordingly, frequency extending over a wide range is controlled by controlling inrush currents in the DBR section 30, oscillation frequency is tuned previously at a desired value, and the voltage of the phase control section 20 is modulated, thus simultaneously realizing the control of frequency extending over the wide range and FM at high speed. |
