| 摘要 |
PURPOSE:To improve and stabilize the dependency of a transmission characteristic on temp. and mechanical characteristic by covering a thermosetting resin reinforced with carbon fibers or arom. polyamide fibers on the outside of an optical fiber strand at a specific lamination angle or below. CONSTITUTION:A primary layer 2 and a buffer layer 3 are provided on an optical fiber 1, and in the stage of forming a secondary coverong layer 4 thereon, carbon fibers or arom. polyamide fibers 6 from bobbins 8 are passed through a tank 7 contg. the liquid of a thermosetting resin such as an unsatd. polyester resin, epoxy resin or the like toward the direction of the fiber 1 to laminte the reinforced resin contg. 40-85% said reinforcing fibers at <=40 deg., more preferably 30 deg. lamination angle to the direction of the fiber 1, thereby forming the layer 4. A three-layered lamination is shown in the figure, and may be more. The fiber is formed to a prescribed diameter by a forming die 2, and is thereafter passed thriugh a heating and curing furnace 3'. The heated fiber is taken off with a take-off 4' and the core is taken up on a take-up device 5. The layer 4 having the coefft. of expansion extremely approximate to that of the fiber 1 is thus formed and the core having high strength and a low transmission loss in a wide temp. range is obtd. |
