Optical Fiber Ribbon Peripheral Resin Roughness Control

The patent applies a peripheral resin portion with specific surface roughness characteristics (Ra ≤ 0.41 μm) only at critical locations where optical fibers are most susceptible to microbending, rather than uniformly coating all surfaces. This localized treatment with differentiated surface properties reduces microbending loss at problem areas while maintaining the intermittent connection structure's pressure-relief benefits.

The patent controls the surface roughness parameter of the peripheral resin portion to be Ra ≤ 0.41 μm, which is a specific quantitative threshold. By adjusting this surface roughness parameter to an optimal range, the patent resolves the contradiction between reducing lateral pressure and preventing microbending loss, as the smooth surface reduces friction and mechanical stress concentration points.

The patent segments the resin coating into two distinct functional parts: connecting portions that intermittently join adjacent optical fibers, and peripheral resin portions that wrap around individual fibers. This segmentation allows each part to be optimized independently - the connecting portions provide mechanical bonding while the peripheral portions provide surface smoothness control (Ra ≤ 0.41 μm) to prevent microbending, simplifying the overall manufacturing approach.

The peripheral resin portion serves multiple functions simultaneously: it provides mechanical support to the optical fibers, controls surface roughness to prevent microbending loss, and maintains the intermittent connection structure. This multi-functionality reduces the need for additional separate components or processing steps, thereby managing manufacturing complexity while achieving microbending loss reduction.