Optical-fiber ribbon, die, and method of manufacturing optical-fiber ribbon

An optical-fiber ribbon comprising:

• a plurality of optical-fibers;
• and
• a common covering layer configured to cover and integrate the plurality of optical-fibers,
• wherein there are formed a plurality of intermittent connection portions in which, in a longitudinal direction of the plurality of optical-fibers, a first connection portion that is formed from the common covering layer and a non-connection portion that is formed by forming a cut in the common covering layer are alternately formed between every two or more of predetermined ones of the optical-fibers,
• wherein there are formed a plurality of continuous connection portions in which, in the longitudinal direction, a second connection portion that is formed from the common covering layer is continuously formed between optical-fibers other than between the optical-fibers where the plurality of intermittent connection portions are formed,
• wherein the plurality of optical-fibers are even in number,
• wherein the plurality of intermittent connection portions include a central intermittent connection portion at a central portion of the optical-fiber ribbon in a width direction,
• wherein the plurality of continuous connection portions include, at two pairs of the optical-fibers between which the central portion is interposed in the width direction, adjacent continuous connection portions, each being formed between a corresponding pair of the two pairs of the optical-fibers, and
• wherein a thickness of each adjacent continuous connection portion is larger than a thickness of the central intermittent connection portion and is larger than a thickness of the continuous connection portion or the continuous connection portions other than the adjacent continuous connection portions.