In what application would single-mode fiber be preferred over multi-mode fiber?

Single-mode fiber is preferred in long-distance telecommunications applications due to its ability to transmit light over vast distances with minimal signal loss and attenuation. This is primarily because single-mode fiber has a smaller core diameter, allowing only one mode of light to propagate through the fiber. This characteristic significantly reduces modal dispersion, which can lead to distorted signals over long distances.

In long-distance telecommunications, where signals need to travel hundreds or even thousands of kilometers, single-mode fiber’s efficiency in maintaining signal integrity makes it the ideal choice. It enables higher bandwidths and longer transmission distances compared to multi-mode fiber, which is more suited for shorter distances due to its larger core that allows multiple light modes to propagate, resulting in increased dispersion and signal degradation over longer runs.

In contrast, the other applications listed, such as short-range connections within a building, local area networks, and video surveillance systems, would typically utilize multi-mode fiber. Multi-mode is more cost-effective for short distances and can support the high data rates required in those environments, but it does not retain signal quality as effectively as single-mode over long distances. Thus, the preference for single-mode fiber in long-distance telecommunications is clear, offering superior performance for extensive network requirements.