Will there be any loss when splicing optical cables from different batches

Splicing optical fibers from different batches can result in small but measurable signal loss due to intrinsic differences in fiber properties.Why Loss Can OccurEven when fibers are manufactured to the same specifications, slight variations exist between batches. These intrinsic factors include differences in:Core diameter: If the transmitting fiber's core is larger than the receiving fiber's core, light at the edges may be lost, especially in multimode fibers .Mode Field Diameter (MFD): In single-mode fibers, a mismatch in MFD between fibers from different batches can cause light to spread differently, leading to splice loss .Numerical Aperture (NA): Differences in NA affect the acceptance angle of light entering the fiber. A larger NA in the transmitting fiber than in the receiving fiber can result in light loss .Typical Loss ValuesFusion splicing: Loss is usually very low, typically 0.05–0.1 dB, even when fibers are from different batches, provided the splice is well executed .Mechanical splicing: Loss can be higher, around 0.2–0.3 dB, due to alignment limitations and batch variations .Mode field diameter mismatch: For single-mode fibers, a 1 µm difference in MFD can produce intrinsic splice loss up to 0.05 dB .Minimizing LossPrecise alignment: Using high-quality fusion splicers ensures the fiber cores are aligned accurately, reducing extrinsic loss .Cleaning fiber ends: Contaminants can increase loss, so proper cleaning is essential .Testing and verification: Using an OTDR or power meter to measure splice loss helps identify and correct weak points .Batch selection: When possible, splicing fibers from the same batch or with closely matched specifications reduces intrinsic mismatch.ConclusionWhile splicing fibers from different batches can introduce minor losses, modern fusion splicing techniques and careful handling typically keep these losses very low, often below 0.1 dB. The main contributors are intrinsic differences in core diameter, MFD, and NA, but with proper alignment and testing, the impact on network performance is minimal .