METHOD AND SYSTEM FOR IDENTIFYING OSCILLATION POSITION USING OPTICAL FIBER RING INTERFERENCE TYPE OSCILLATION SENSOR

• Main Authors: INOUE FUMIYOSHI, FUKUDA TSUNEHIRO, OMORI TATSUYA, YAMAGUCHI MASATSUNE, TAKASHIMA TORU, HASHIMOTO KIYONARI, OSAWA NORITAKA
• Format: Patent
• Language: English
• Published: 24.12.2004
• Edition: 7
• Subjects: ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVEREDIN A SINGLE OTHER SUBCLASS; MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR; PHYSICS; TARIFF METERING APPARATUS; TESTING

PROBLEM TO BE SOLVED: To provide a method and a system for identifying oscillation position by detecting the oscillation applied to a part of an optical fiber with a simple configuration. SOLUTION: An optical fiber ring interferometer comprises a correlator 20 in which the optical interference intensity signal outputted for light receiving parts 6 and 11 is sampled to obtain discrete data which are set with a window of a specified width. A self correlation function is acquired from the data in the window, and a maximum value of equal to or higher than a prescribed value is detected from the self correlation function. If the maximum value whose correlation time is other than zero exists, the position where the optical fiber is applied with phase fluctuation is calculated based on the correlation time of the detected maximum value and the propagation speed of light in the optical fiber. COPYRIGHT: (C)2005,JPO&NCIPI