Fiber optic splice fiber too thin

A fiber optic splice that appears too thin is usually caused by insufficient fiber feed or an overly strong discharge arc during fusion splicing, which can increase splice loss and reduce mechanical strength.Causes of Thin Fiber SplicesInsufficient Fiber Feed: When the fiber is not fed adequately into the fusion splicer, the resulting splice can be thinner than normal. This reduces the contact area between the fibers, leading to higher optical loss and weaker mechanical strength .Excessive Arc Power: A discharge arc that is too strong can over-melt the fiber ends, causing them to shrink and form a thin splice. This can also distort the fiber core and increase insertion loss .Contamination: Dust, dirt, or residual coating on the fiber can prevent proper fusion, sometimes resulting in a thin or uneven splice. Cleaning the fiber thoroughly before splicing is essential .Core or Mode Field Mismatch: Differences in core diameter or mode field diameter between fibers can exacerbate the appearance of a thin splice and increase signal loss .Solutions and Best PracticesAdjust Arc and Feed Parameters: Modify the fusion splicer's arc power and fiber feed settings to ensure proper melting and alignment. Most modern splicers allow automatic calibration, but manual fine-tuning may be necessary for unusual fiber types .Proper Fiber Preparation: Strip the coating carefully without nicking the glass, and cleave the fiber ends to produce a flat, perpendicular surface. Use a precision cleaver and inspect under a microscope to avoid chips or cracks .Cleanliness: Always clean fibers with approved alcohol wipes or fiber cleaning kits before splicing. Ensure the V-grooves and lenses of the splicer are free from dust .Alignment Verification: Use the splicer's camera system to check that fiber cores are properly aligned. Even a small offset can result in thin or weak splices .Test and Rework if Necessary: Measure splice loss with an OTDR or power meter. If the splice is too thin or shows high loss, re-splice after adjusting parameters and cleaning the fibers .SummaryA thin fiber splice is typically a result of insufficient feed, excessive arc, or contamination, and it can compromise both optical performance and mechanical strength. Correcting the issue involves adjusting splicer settings, ensuring proper fiber preparation, maintaining cleanliness, and verifying alignment to achieve a strong, low-loss splice .