| 摘要 |
PURPOSE:To stabilize transmission characteristics, mechanical characteristics, etc., by determining the position of an optical fiber core at the position coinciding with the neutral plane of bending when an optical fiber cable is bent with the side of tension bodies offcentered from the central point of the cable as an inner side. CONSTITUTION:The tension members 4A, 4B having a high Young's modulus are eccentrically embedded in a plastic wire-shaped body 6 housed with an optical fiber unit 2 or optical fiber core 3 in a groove 7. The position where the longitudinal elongation and contraction by bending the cable 1 do not arise at the time of bending the cable with the position of the tensile bodies offcentered from the central point 0 of the cable as the inner side in the section of the cable, i.e., the neutral plane of bending the cable is set at the position where the optical fiber unit 2 or optical fiber core 3 is disposed. The length of the unit 2 or the core 3 is thereby equaled always to the length of the cable. The leading in or projection of the optical fiber unit or optical fiber core at the cable terminal during extending or bending of the cable 1 is thus obviated; in addition, generation of strain in the optical fiber is prevented. Since unwanted force is not applied on the optical fiber, the stable transmission characteristics are assured. |
