The height of a butterfly-shaped optical cable is determined by the combined thickness of its semi-cylindrical fiber units and the central transition section, forming a compact rhombus-like cross section.

Cross-Sectional Structure

Butterfly-shaped optical cables are named for their wing-like cross-sectional design, which typically consists of two semi-cylindrical fiber-containing units on either side of a central cuboid or transition section . The height of the cable is measured from the top of one semi-cylindrical unit to the bottom of the opposite unit, including the central transition section. This design allows the cable to maintain a low profile while accommodating multiple optical fibers and strength members.

Component Heights

• First and Second Semi-Cylindrical Units: These house the optical fibers and reinforcing members. Each unit contributes to the overall height, with the fiber-containing cavity slightly taller than the connecting sections .
• Transition Section: The cuboid-shaped middle section connects the two semi-cylindrical units. Its height is smaller than the semi-cylindrical units, ensuring a smooth, compact profile .
• Protective Layer and Outer Sheath: The protective layer and outer sheath add minimal additional height but provide mechanical protection, moisture resistance, and UV protection .

Practical Implications

The butterfly-shaped design results in a rhombus-like or flattened profile, which is advantageous for:

• Conduit entry: Easier insertion into ducts and pipelines due to the low height-to-width ratio .
• Space efficiency: Reduced pole or conduit space usage compared to circular cables .
• Flexibility: Simplified splicing and expansion in FTTH networks or pipeline applications .

Summary

While exact numerical height values vary by manufacturer and fiber count, the overall height is defined by the sum of the two semi-cylindrical fiber units plus the central transition section, typically resulting in a compact, low-profile cable suitable for FTTH, pipeline, and high-density optical deployments . The design prioritizes space efficiency, mechanical protection, and ease of installation.