| 摘要 |
PROBLEM TO BE SOLVED: To provide a coherent optical detector having a multifunctional waveguide grating.SOLUTION: A waveguide grating 342 serves at least three different functions, e.g., those of a fiber-optic coupler 320, a polarization splitter, and two power splitters, one for each of two orthogonal polarizations. A coherent optical detector 300 can be used to demodulate various forms of polarization-division-multiplexed (PDM) QAM- and/or PSK-modulated optical communication signals. |
