Abstract: An optical fiber ribbon includes: optical fibers disposed side by side in a predetermined direction; and connecting portions that connect two adjacent ones of the optical fibers. A peripheral resin portion is formed on a periphery of the optical fibers. An arithmetic mean roughness Ra of a surface of the peripheral resin portion is 0.41 ?m or lower. A ten-point mean roughness Rz of a surface of the peripheral resin portion is 1.4 ?m or lower.

Abstract: [Problem] When a surface of the optical fiber ribbon is rough, the microbending loss is increased due to the irregularities formed on the surface of the optical fiber ribbon. [Solution] An intermittently connected optical fiber ribbon of the present disclosure, includes: a plurality of optical fibers arranged in a predetermined direction; and connecting portions that intermittently connect two adjacent ones of the optical fibers. A peripheral cover portion formed of resin configuring the connecting portions is formed on a periphery of the optical fibers. An arithmetic mean roughness Ra of a surface of the peripheral cover portion is 0.41 ?m or lower.

Abstract: [Problem] When a surface of the optical fiber ribbon is rough, the microbending loss is increased due to the irregularities formed on the surface of the optical fiber ribbon. [Solution] An intermittently connected optical fiber ribbon of the present disclosure, includes: a plurality of optical fibers arranged in a predetermined direction; and connecting portions that intermittently connect two adjacent ones of the optical fibers. A peripheral cover portion formed of resin configuring the connecting portions is formed on a periphery of the optical fibers. An arithmetic mean roughness Ra of a surface of the peripheral cover portion is 0.41 ?m or lower.