What are the methods for multimode fiber optic terminal fusion splicing

Fusion splicing multimode fibers requires precise fiber preparation, proper alignment, controlled splicing parameters, and strict safety measures to achieve low-loss, reliable connections.Fiber PreparationStripping the Fiber: Remove the protective coating carefully using multi-hole strippers calibrated for multimode fibers (typically 250µm bare fiber and 900µm coated fiber) to avoid microfractures or nicks in the glass core .Cleaning: Use lint-free wipes with 99%+ isopropyl alcohol to clean the stripped fiber from the coating edge to the cleave tip in a single downward stroke to prevent contamination .Cleaving: A precision fiber cleaver is required to produce a flat, perpendicular end face. The quality of the cleave directly affects splice loss and reliability .Splicing Equipment and AlignmentFusion Splicer: Use an automated fusion splicer with factory-recommended settings for multimode fibers. The splicer aligns fibers using optical core alignment or profile alignment, illuminating the fibers from two directions and adjusting movable stages to minimize splice loss .Parameter Settings: Multimode fibers may require specific arc power and duration settings due to their larger core and graded-index profile. Follow the splicer manufacturer's guidelines for multimode fiber splicing .Fiber Holders: Ensure fibers are held steadily in the splicer to prevent misalignment during the fusion process .Safety RequirementsPersonal Protection: Wear industrial safety goggles and cut-resistant shoes to protect against burns from the fusion arc (over 5,000°C) and glass shards .Workspace Safety: Use anti-static mats or wrist straps to prevent static damage to splicer electronics and dispose of fiber shards in dedicated containers .Quality Control and Loss ConsiderationsSplice Loss: Typical fusion splice loss for multimode fibers is less than 0.1 dB. Loss can result from fiber misalignment, core size mismatch, numerical aperture differences, or non-circularity of the fiber core .Inspection: After splicing, inspect the splice using the splicer's built-in loss estimation or an optical time-domain reflectometer (OTDR) to verify low-loss performance .Protection: Apply splice protection sleeves to maintain mechanical strength and prevent environmental damage .Summary WorkflowStrip and clean the fiber coating.Cleave the fiber ends precisely.Load fibers into the fusion splicer and select multimode settings.Align fibers using optical core alignment.Execute the fusion splice and inspect for quality.Protect the splice with a sleeve and store properly. Following these requirements ensures high-performance, low-loss multimode fiber splices suitable for permanent network installations .