PLANAR LIGHTWAVE CIRCUIT AND OPTICAL RECEIVER

摘要

A planar lightwave circuit and an optical receiver which reduce degradation in signal quality is provided.;A planar lightwave circuit includes: a substrate with a straight groove formed therein; a signal light input port which is formed in the substrate and receives signal light; a first planar filter part which is fitted into the groove and separates the signal light into a signal light component including a first polarization state and that including a second polarization state; a second planar filter part which is fitted into the groove and separates the local oscillator light into a local oscillator light component including the first polarization state and that including the second polarization state; a first interference part formed in the substrate; a second interference part which is formed on a side of the substrate opposite to the side of the first interference part across the groove; a first waveguide which is connected to the signal light input port and also to a reflection surface of the first planar filter part; a second and a third waveguide; a fourth waveguide which is connected to the local oscillator light input port and also to a reflection surface of the second planar filter part; and a fifth and a sixth waveguide.

主权项

1. A planar lightwave circuit, comprising:
a substrate with a straight groove being formed therein; a signal light input port formed in said substrate and receiving polarization-multiplexed signal light; a local oscillator light input port formed in said substrate and receiving polarization-multiplexed local oscillator light; a first planar filter part fitted into said groove and separating said signal light into a signal light component comprising a first polarization state and a signal light component comprising a second polarization state; a second planar filter part fitted into said groove and separating said local oscillator light into a local oscillator light component comprising the first polarization state and a local oscillator light component comprising the second polarization state; a first interference part formed in said substrate; a second interference part formed on a side of said substrate opposite to the side of said first interference part across the groove; a first waveguide connected to said signal light input port and connected diagonally to a reflection surface of said first planar filter part; a second waveguide connected to said first interference part and to said first planar filter part, and guiding said signal light component comprising the first polarization state; a third waveguide connected to said second interference part and to said first planar filter part, and guiding said signal light component comprising the second polarization state; a fourth waveguide connected to said local oscillator light input port and also connected diagonally to a reflection surface of said second planar filter part; a fifth waveguide connected to said first interference part and to said second planar filter part, and guiding said local oscillator light component comprising the first polarization state; and a sixth waveguide connected to said second interference part and to said second planar filter part, and guiding said local oscillator light component comprising the second polarization state.