OPTICAL FILTER EXISTENCE CONFIRMATION METHOD AND OPTICAL FILTER EXISTENCE CONFIRMATION DEVICE OF OPTICAL PATH

摘要

PROBLEM TO BE SOLVED: To provide an optical fiber existence confirmation method of an optical path for determining current use/non-current use of a furthermore lower part than a branch point, when a loss of a lower optical path is large, in a PON (Passive Optical Network) having an optical branch element.;SOLUTION: In this optical fiber existence confirmation method of the optical path for determining existence of test light shielding filters 18, 21 at lower ends of the optical path comprising one upper optical fiber cable 15 and a plurality of lower optical fiber cores 17, 20, 23, 25 branched by an optical splitter 16, existence of the lower optical fiber cores 17, 20, 23, 25 having an excessive loss and the test light shielding filters 18, 21 at the lower ends thereof is determined by applying approximate calculation for removing an influence of incident test light.;COPYRIGHT: (C)2009,JPO&INPIT