Abstract: [Object] To provide an interferometric optical fiber gyroscope that can perform higher-accuracy measurement and can be produced at a low cost. [Solving Means] An interferometric optical fiber gyroscope is an interferometric optical fiber gyroscope that detects angular velocity by optical interference between counterclockwise light and clockwise light. In such an interferometric optical fiber gyroscope that detects angular velocity by optical interference between counterclockwise light and clockwise light, the interferometric optical fiber gyroscope includes: a sensing coil mechanism including a multicore fiber that includes a plurality of transmission cores, and a multicore fiber optical path junction that optically couples at least a first transmission core and a second transmission core, of the plurality of transmission cores.

Abstract: A method of repairing an embedded optical fiber of a composite material structure including an embedded optical fiber embedded in a composite material, includes removing a portion of the composite material including a damaged portion of the embedded optical fiber to form an opening portion; polishing an end surface of the embedded optical fiber exposed in the opening portion and an end surface of the composite material exposed in the opening portion; and performing position adjustment such that a core of the polished embedded optical fiber and a core of a replacement optical fiber are aligned with each other, butting the end surface of the embedded optical fiber and an end surface of the replacement optical fiber with each other, and connecting the end surface of the embedded optical fiber and the end surface of the replacement optical fiber together.

Abstract: A method of repairing an embedded optical fiber of a composite material structure including an embedded optical fiber embedded in a composite material, includes removing a portion of the composite material including a damaged portion of the embedded optical fiber to form an opening portion; polishing an end surface of the embedded optical fiber exposed in the opening portion and an end surface of the composite material exposed in the opening portion; and performing position adjustment such that a core of the polished embedded optical fiber and a core of a replacement optical fiber are aligned with each other, butting the end surface of the embedded optical fiber and an end surface of the replacement optical fiber with each other, and connecting the end surface of the embedded optical fiber and the end surface of the replacement optical fiber together.