Patent ID: 8787718

Claim:
An optical fiber ribbon, comprising: four single-core coated optical fibers arranged in parallel on a same plane; and coupling parts arranged at intervals in a length direction and a width direction, each of the coupling parts coupling only adjacent two of the single-core coated optical fibers, wherein the coupling parts coupling each of the two outer optical fibers of the four optical fibers and each of the two inner optical fibers adjacent to each of them respectively are the same in length and each disposed so as to be substantially at a length-direction, the coupling parts coupling the two inner optical fibers of the four optical fibers are the same in length and each disposed so as to be substantially at a length-direction middle between the outer coupling parts, and an interval P of the coupling parts coupling the same two single-core coated optical fibers is not less than 45 mm nor more than 65 mm, and a length Q of each of the coupling parts is not less than 2 mm nor more than 4 mm.