Driving method of acousto-optical filter, optical communication systems and optical add-drop devices as well as the selected wavelength expansion and method of acousto-optic filter

摘要

PROBLEM TO BE SOLVED: To provide an acoustooptical filter driving method, an acoustooptical filter, an extension method of a selected wavelength, an optical branching and insertion device, and an optical communication system enabling to miniaturize a driving device which can suppresse a temporal variation of output characteristics in the acoustooptical filter. ;SOLUTION: When distributing RF signals to the number matched to the number of stages of AOTFs 16 which is cascade connected, while adjusting the phase of RF signal, after collecting RF signals whose phases are adjusted identically to distribute and dividing a plurality of RF signals into groups, RF signals are put in block for every group. The signals in bloc are distributed to the number of stages, adjusting the phases so that phases of beats generated from a plurality of RF signals to one AOTF 16 become different phases between a plurality of AOTF 16.;COPYRIGHT: (C)2001,JPO