| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical branching device which can adjust intensity of signal light extracted from an optical transmission line.SOLUTION: An optical branching device comprises: an optical transmission line 10 for transmitting signal light; an extraction section 15 disposed in the vicinity of the optical transmission line 10 to extract evanescent light which is signal light leaked from the optical transmission line 10; an intensity detection section 19 for detecting intensity of the evanescent light extracted by the extraction section 15; and a control section 19 for adjusting the position of the extraction section 15 on the basis of the intensity detected. |
