| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to prevent the local stress concentration by bending stresses and to arrange an optical fiber formed with gratings on the core of a bare optical fiber exposed by removing the coating formed on the outer side of the bare optical fiber into an optical fiber cable of a small housing space by providing the exposed bare optical fiber with a recoating. SOLUTION: The optical fiber 10 is provided with the coating layer 12 consisting of, for example, UV curing resin, etc., on the outer side of the bare optical fiber 11. The bare optical fiber 11 exposed by removing the coating layer 12 is provided with a recoating layer 13 consisting of the UV curing resin, etc., added with, for example, pigments. At this time, such a material which is capable of preventing the change in the refractive index distribution of the gratings 11a formed on the bare optical fiber 11 at the time of forming the recoating layer 13 is selected for the material of the recoating layer 13. In the case, for example, the recoating layer 13 is the UV curing resin, a material which is curable by UV rays exclusive of a wavelength region 190 to 300nm which is a grating treatment wavelength is selected and used. |
