Which type of optical fiber is typically used for long-distance communication?

Single-mode fiber is typically used for long-distance communication due to its ability to transmit light over longer distances with minimal signal loss. This type of fiber features a small core diameter, which allows only a single mode of light to propagate. Because it minimizes modal dispersion — the spreading of light pulses that can occur when multiple modes travel through a fiber — single-mode fiber can maintain a clear and strong signal over long distances, making it ideal for telecommunications and high-speed data transmission applications.

In comparison, multimode fiber has a larger core that allows multiple light paths or modes to propagate. While it is suitable for shorter distances, the signal degrades more quickly as the distance increases due to modal dispersion.

Plastic optical fiber is advantageous for short-range applications due to its flexibility and ease of installation but is not designed for long-distance communication due to higher attenuation rates.

Standard glass fiber can refer to various types of fiber, and unless specified as single-mode, it may not necessarily provide the long-distance performance characteristic of single-mode fibers. Therefore, single-mode fiber stands out as the most appropriate choice for long-distance optical communication.