Butterfly-shaped optical cables feature a flat, wing-like cross-section, typically ranging from 3 to 5 mm in width, depending on the fiber count and strength member configuration.

Structure and Design

Butterfly optical cables are named for their distinctive flat, wing-shaped cross-section, where the optical fiber is positioned at the center and flanked by two parallel Fiber Reinforced Plastic (FRP) strength members on either side . This design provides directional flexibility, allowing the cable to bend easily along the flat plane while resisting sharp kinks when bent edge-on, which protects the fiber core during installation . Some variants include an additional steel wire strength member for aerial or pipeline applications, enhancing tensile strength .

Typical Dimensions

While exact widths vary by manufacturer and fiber count, standard FTTH butterfly drop cables generally have a cross-sectional width of approximately 3–5 mm and a thickness of 1.5–2.5 mm . The flat profile allows the cable to occupy minimal space, making it ideal for indoor routing along walls, baseboards, or inside conduits . The LSZH (Low-Smoke Zero-Halogen) sheath and optional PE outer layer provide fire safety, UV resistance, and environmental protection .

Advantages of the Butterfly Shape

• Bend-insensitive: Supports tight bend radii (as small as 10–30 mm) without signal loss .
• Space-efficient: Flat profile fits in narrow conduits and along surfaces.
• Durable: FRP and optional steel members provide compression and tensile resistance.
• Easy installation: Lightweight and simple to staple or clip along walls or ceilings. In summary, the cross-sectional width of a butterfly-shaped optical cable is typically 3–5 mm, with the exact size depending on fiber count, strength members, and sheath type, while the flat, wing-like design ensures flexibility, durability, and space efficiency for FTTH and pipeline applications .