What is the purpose of buffer tubes in a fiber-optic cable?

Buffer tubes in a fiber-optic cable serve a critical function by protecting and separating the individual optical fibers within the cable. These tubes are designed to provide a physical barrier that safeguards the delicate glass fibers from environmental factors such as moisture, temperature fluctuations, and physical stress. This protection is essential as optical fibers are fragile and can break easily if not adequately shielded.

In addition to offering protection, buffer tubes also help in organizing the fibers, allowing for easier handling and installation. They can accommodate variations in fiber count, meaning that they can separate and manage multiple fibers within the same cable structure without causing any damage or inducing signal loss. This design consideration is important for maintaining the integrity and performance of the optical signals transmitted through the fibers.

The other options do not accurately reflect the primary role of buffer tubes. They do not serve to improve the efficiency of fiber connections, act as conduits for electrical signals, or primarily function to increase the cable's overall diameter. Instead, they focus specifically on protecting and organizing the fibers, which is a vital aspect of fiber-optic cable design and performance.