US 12,313,491 B2
Optical fiber bending loss measuring method
Chonde Tei, Utsunomiya (JP); Tomoaki Hatanaka, Utsunomiya (JP); Yuki Kawaguchi, Osaka (JP); and Tomoko Terauchi, Utsunomiya (JP)
Assigned to SUMITOMO ELECTRIC INDUSTRIES, LTD., Osaka (JP)
Appl. No. 18/009,509
Filed by SUMITOMO ELECTRIC INDUSTRIES, LTD., Osaka (JP)
PCT Filed Jun. 10, 2021, PCT No. PCT/JP2021/022200
§ 371(c)(1), (2) Date Dec. 9, 2022,
PCT Pub. No. WO2021/251474, PCT Pub. Date Dec. 16, 2021.
Claims priority of application No. 2020-102574 (JP), filed on Jun. 12, 2020.
Prior Publication US 2023/0314278 A1, Oct. 5, 2023
Int. Cl. G01M 11/00 (2006.01)
CPC G01M 11/33 (2013.01) 5 Claims
OG exemplary drawing
 
1. An optical fiber bending loss measuring method for obtaining a bending loss of an optical fiber by applying bending to the optical fiber by using a plurality of mandrels provided between a feeding portion of the optical fiber and a fixing portion of the optical fiber and arranged alternately in a longitudinal direction of the optical fiber, the adjacent mandrels being a fixed mandrel that is configured not to move, and a movable mandrel that is movable between a reference position at which bending is not applied to the optical fiber and a forward position at which the bending is applied to the optical fiber, the optical fiber bending loss measuring method comprising:
fixing the optical fiber to the fixing portion by passing the optical fiber fed out from the feeding portion between the mandrels in a state in which the optical fiber is not disposed between the adjacent mandrels;
moving the movable mandrel to the forward position and applying bending to the optical fiber by holding the optical fiber between the adjacent mandrels so as to bend the optical fiber at a predetermined angle with respect to the longitudinal direction; and
obtaining the bending loss of the optical fiber while the bending is applied to the optical fiber,
wherein among a plurality of the movable mandrels, a movable mandrel located in a vicinity of the fixing portion is moved before a movable mandrel located in a vicinity of the feeding portion to apply the bending to the optical fiber.