| 摘要 |
PROBLEM TO BE SOLVED: To improve a device scale and power consumption and to generate QAM signals. SOLUTION: The optical device is provided with multivalue modulation parts 25 and 26 for performing mutually independent multivalue modulation for input light, and one multivalue modulation part 25 includes an inner side Mach-Zehnder waveguide 25a having two inner side arm waveguides 25ab and 25ac, and two signal electrodes 25b-1 and 25b-2 for supplying the electric field for supplying interaction with light propagated through the inner side Mach-Zehnder waveguide. The inner side Mach-Zehnder waveguide or the signal electrodes are provided with even number of pieces of crossing parts where a pair of the inner side arm waveguide and the signal electrode for supplying the electric field for giving the interaction is mutually replaced, and a polarization inversion area 11 is formed in the light propagation area of the inner side arm waveguide in which at least one of the crossing parts is a boundary. COPYRIGHT: (C)2010,JPO&INPIT |
