| 摘要 |
PURPOSE: To allow the filter to track accurately a peak transmitted wavelength by arranging a BPF in a collimated optical path in a freely oscillating way and providing an angle monitor, an optical output monitor, an optical filter control circuit and an optical output storage circuit. CONSTITUTION: A relational equation between a tilt angle and a transmitted wavelength is given in advance to a CPU 4, which controls an angle monitor 8, an optical output monitor 5, and an optical filter control circuit 7. A BPF 2 is oscillated over its entire range to scan a multiplex signal light transmitted through an optical fiber 1. The tilt angle of the BPF 2 is detected by a monitor 8 and the light intensity at that time is detected by the monitor 5. A peak transmitted wavelength and its optical output valve are calculated based on the relational equation between a tilt angle and a transmitted wavelength and measured data and the optical output valve is stored in an optical output storage circuit 6. The BPF 2 is roughly adjusted to a desired peak transmitted wavelength and the CPU 4 is used to track the accurate peak transmitted wavelength. Furthermore, an unknown peak transmitted wavelength is similarly detected and sensed. |
