| 摘要 |
PROBLEM TO BE SOLVED: To shorten the oscillation wavelength of an optical semiconductor device, by connecting a first resistor with a current inputting electrode for driving its laser diode, and by connecting a second resistor between a current inputting electrode for driving its modulator and a grounding electrode of its modulator, and further, by connecting one end of a third resistor to the grounding electrode and the other end to the ground. SOLUTION: Making a driving current flow from a DC power supply V0 to a laser- side surface electrode 9 of an LD 14 with a modulator 100 via a first resistor 31, a laser beam is generated in the active layer of an LD 200 to output the laser beam from the end surface of the LD 14 via the vicinity of the active layer of the modulator 100. When applying such a modulating signal (V) of a negative voltage from a strip line 18 for feeding a power to the modulator 100 to a modulator-side front electrode 8 as to bias reversely the p-n junction in the modulator 100, the active layer of the modulator 100 absorbs the light emission from the active layer of the LD 200. But, the active layer does not absorb the light emission to transmit it when reducing the applied modulating signal V to zero volt. Since the related varying rate of the oscillating wavelength of the LD 200 to a modulating injection current is -0.1Å/mA, the wavelength of the laser beam can be shortened when absorbing the foregoing light emission. |
