Structure of bare fiber pigtail

A bare fiber pigtail consists of a factory-terminated connector on one end and an exposed, unjacketed optical fiber on the other, designed for splicing into a fiber optic cable.

Key Components

Connector End: The factory-terminated end features a polished connector (e.g., LC, SC, FC) that ensures low insertion loss and high return loss. Connectors may be PC (Physical Contact), UPC (Ultra Physical Contact), or APC (Angled Physical Contact), with APC angled at 8° to reduce back reflection, commonly used in CATV, FTTx, and WDM systems . Bare Fiber End: The opposite end is an exposed optical fiber, typically 0.9mm in diameter for tight-buffered indoor pigtails. This bare fiber is intended for fusion or mechanical splicing to the main fiber cable, creating a permanent, low-loss connection . Fiber Type and Structure: Pigtails are available in single-mode or multimode fibers, and may be color-coded according to TIA/EIA standards for easy identification. The fiber itself is usually unjacketed or minimally buffered, as it will be housed inside an ODF, splice tray, or terminal box . Protective Layers: While standard indoor pigtails have minimal protection, specialized types include:

• Armored pigtails: Stainless steel tube inside the outer jacket for rodent and mechanical protection.
• Waterproof pigtails: Reinforced with a waterproof PE jacket for outdoor or harsh environments .

Typical Dimensions and Variants

• Length: Usually 0.5m to 2m.
• Fiber Count: Simplex (1 fiber) is most common, but multi-fiber pigtails exist (2, 4, 6, 8, 12, 24, 48, 72 fibers).
• Cable Diameter: 0.9mm for tight-buffered fibers; 2.0mm or 3.0mm for more robust or outdoor variants .

Applications

Bare fiber pigtails are primarily used to splice fibers from a bulk cable to a connectorized interface in ODFs, patch panels, or terminal boxes. They provide factory-grade connector performance while allowing flexible field splicing, making them ideal for permanent terminations in high-density or structured cabling environments .

Summary

In essence, a bare fiber pigtail combines the precision of a factory-polished connector with the flexibility of a bare fiber for splicing, available in various fiber types, connector styles, and protective configurations to suit indoor, outdoor, and high-density applications .