Butterfly-shaped optical cable without reinforcing core

A butterfly-shaped optical cable without a reinforcing core is a flat, flexible fiber optic cable designed for FTTH applications, featuring parallel fiber ribbons and a lightweight, non-reinforced structure for easy installation.

Structure and Design

Butterfly-shaped optical cables are named for their flat, wing-like cross-section, which allows for simple routing in buildings and tight spaces . In non-reinforced versions, the cable lacks a central strength member, relying instead on the cable jacket and optional side reinforcement for mechanical protection . The fibers are typically arranged in two parallel ribbons at the center of the cable, which can be single-mode or multi-mode depending on the application . The absence of a reinforcing core makes the cable lighter and more flexible, which is advantageous for indoor installations or short-distance FTTH deployments where high tensile strength is not critical . These cables often use LSZH (Low Smoke Zero Halogen) jackets, providing flame retardancy and safety in indoor environments .

Fiber and Performance

Non-reinforced butterfly cables commonly use G.657A2 small bending radius fibers, which allow the cable to be bent to radii as small as 20 mm without significant signal loss . This ensures stable optical transmission even in tight corners or complex building layouts. The fiber count can range from 2 to 12 cores, and each core can be terminated independently, simplifying splicing and connection .

Installation and Applications

The flat, flexible design of non-reinforced butterfly cables makes them easy to handle, strip, and splice, reducing installation time and labor . They are ideal for FTTH drop cables, indoor routing, and environments where the cable will not be subjected to heavy pulling or outdoor mechanical stress. While they do not have a central reinforcing core, some designs include parallel side FRP or aramid yarn members to provide minimal crush resistance and protect the fibers .

Advantages

• Lightweight and flexible, suitable for indoor and short-distance installations
• Easy to splice and terminate, with independent core access
• Supports tight bending radii without signal degradation
• Flame-retardant LSZH jacket ensures safety in buildings
• Cost-effective compared to reinforced or self-supporting cables In summary, a butterfly-shaped optical cable without a reinforcing core is a practical, flexible solution for FTTH networks, offering ease of installation, reliable optical performance, and safety features, while being optimized for environments where mechanical stress is minimal .