| 摘要 |
PURPOSE:To avoid intermission of communication due to a fault such as deteriorated optical semiconductor by operating plural optical semiconductors in parallel, synthesizing the optical output and modulating the result. CONSTITUTION:An optical communication light source includes laser diodes 2, 3 connected to a laser driver circuit 1, the optical transmitter is provided with a waveguide type multiplexer 4 synthesizing the optical output of the laser diodes 2, 3, a waveguide type optical modulator 5 is formed on the same LiNbO3 board 6 as the waveguide multiplexer 4 and the optical output of the waveguide type multiplexer 4 is modulated by using the output of a driver circuit 7. Two laser diodes are operated in parallel and even if an optical output of one laser diode is decreased due to deteriorated or stopped, the output of the optical transmitter is decreased by 3dB only and no hit of the transmission signal is caused. |
