Patent ID: 7153034

Claim:
An optical transmission line constructing method comprising the steps of: temporarily connecting a plurality of optical fibers in serial to make a provisional transmission line, the plural optical fibers being different among them in a transmission characteristic thereof; making inspection light incident on an entrance end of the provisional transmission line; detecting, on the entrance end side, respective return light components of the inspection light occurring at individual positions of the provisional transmission line in a longitudinal direction thereof; evaluating a characteristic information distribution of return light in the longitudinal direction of the provisional transmission line to get the evaluation result of the provisional transmission line; and when the result of the evaluation of the provisional transmission line is desired, connecting the plurality of the optical fibers of the provisional transmission line among them to construct a desired optical transmission line and, when the result of the evaluation of the provisional transmission line is not desired, changing one of the plurality of the optical fibers of the provisional transmission line into another optical fiber of which transmission characteristics is different from the changed optical fiber, to make a new provisional transmission line and perform the evaluation of the new provisional transmission line to construct a desired optical transmission line.