PHASE-CONTROLLED LIGHT FSK MODULATOR

摘要

It is an object of the present invention to provide an optical modulator capable of controlling the phase of a USB signal and the phase of an LSB signal of an optical FSK modulated signal. A modulation signal is applied to a main Mach-Zehnder electrode (or an electrode C) (11) of a main Mach-Zehnder waveguide (MZ C ) (8) to switch the USB signal and the LSB signal, and so FSK modulation can be made. In order to control the phase of the optical signal to be outputted from the main Mach-Zehnder waveguide (MZ C ) (8), bias voltage is applied to the main Mach-Zehnder electrode (11), and the phases of the USB signal and the LSB signal are controlled which have not been considered in the prior art. By doing so, FSK modulation with adjusted phases can be performed.