OPTICAL LINE HAVING IDENTIFICATION MARKER

PROBLEM TO BE SOLVED: To make it possible to rapidly execute the processing to read identification markers which reflect one or >=2 wavelengths selected from plural wavelengths as main reflection wavelengths by disposing these identification markers at both ends of respective segment lines. SOLUTION: The respective both ends of the segment lines 1a, 1b constituted of optical fibers are provided with connectors 4 and are provided with the identification markers 2 by combination of plural reflection parts near both ends. The identification markers 2 of the segment lines 1a, 1b are the same here and the main refractive wavelengths of the identification markers 2 at the left ends of all the segment lines are λ1, λ2 among five kinds of the wavelengths λ1 to λ5 and the reflection wavelengths at the right ends are λ1, λ2, λ5. The identification markers 2 are concentrated to the junctures of the respective segment lines if the optical line are constituted by connecting plural pieces of the segment lines 1a, 1b... provided with the identification markers 2 at both ends in such a manner. The distances from the one end of the optical lines to the respective junctures are detectable and are, in some cases, known and, therefore, the reading of the identification markers 2 is made possible simply by selectively investigating the parts near these distances.