| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce ASE (Amplified Spontaneous Emission) noise within a signal band. <P>SOLUTION: A polarization beam splitter (PBS) 24 splits the output light of a polarized wave controller 22 into a first component containing signal light and noise components and a second component containing only the noise components, supplying the first component to a first arm and the second component to a second arm, respectively. A half wave plate 32 upon the first arm rotates in the polarization direction of the first component at 90°. An optical circulator 38 and a spectroscopic delay device 40 invert an optical phase of the second component. A multiplexer 48 multiplexes the first component that has propagated the first arm, and the second component that has propagated the second arm. When multiplexing, the noise components contained in the first component and second component (the noise components) interfere with each other, thereby weakening the noise components within the signal band. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
