Optical fiber holder and method for connecting coated optical fibers

An optical fiber holder comprising:

• a holder body including an accommodating portion, the accommodating portion being configured to accommodate a plurality of optical fibers in a state in which the plurality of optical fibers are arranged in parallel;
• and
• a first lid portion configured to be opened and closed relative to the holder body and cover at least a part of the accommodating portion, wherein
• the accommodating portion includes a pitch conversion portion having a plurality of ridge portions arranged in parallel and a plurality of flat bottom portions between the plurality of ridge portions, and
• the plurality of ridge portions have a uniform height of 0.1 mm or less from the bottom portions, and parallel intervals in between enlarge or lessen from one side toward the other side in a longitudinal direction, wherein
• the optical fiber holder further comprises a second lid portion configured to be opened and closed relative to the holder body, cover a region of the accommodating portion that is different from the pitch conversion portion in a state of being closed relative to the holder body, and hold the optical fibers accommodated in the accommodating portion, wherein
• the accommodating portion further includes a first flat portion, and a second flat portion, the first flat portion is disposed in a position where the first flat portion is covered with the second lid portion when the second lid portion is closed, and the second flat portion is disposed in a position where the second flat portion is covered with neither the first lid portion nor the second lid portion.