What are the two main types of optical fibers?

The two main types of optical fibers are single-mode and multi-mode fibers. This classification is primarily based on the way light travels through the fiber and the core diameter of the fibers.

Single-mode fibers have a small core diameter (about 8 to 10 micrometers) that allows only one mode of light to propagate. This property enables single-mode fibers to transmit data over much longer distances with less signal attenuation and distortion compared to multi-mode fibers. They are often used in telecommunications and long-haul applications where high performance is essential.

On the other hand, multi-mode fibers possess a larger core diameter (about 50 to 62.5 micrometers), allowing multiple light modes to travel simultaneously. While this construction permits greater light transmission and is suited for shorter distances and high-bandwidth applications, it can lead to modal dispersion over long distances, which can impair signal quality.

The other options, while relevant aspects of optical fibers, do not define the primary categories that distinguish fiber optics in terms of their operational capabilities and applications. Glass and plastic fibers refer more to the material of construction rather than functionality, while active and passive or thin and thick fibers do not accurately represent the classifications based on light transmission modes.