The two most common core diameters in multi-mode fiber are

The two most common core diameters in multi-mode fiber are

• A. 25 microns and 50 microns
• B. 40 microns and 60 microns
• C. 50 microns and 62.5 microns
• D. 75 microns and 100 microns

Answer: (C)

In multimode fiber, the core diameter determines how many light paths (modes) can propagate and influences bandwidth and coupling. The two most common core diameters are 50 microns and 62.5 microns, which form the standard 50/125 and 62.5/125 fiber types. The 50/125 fiber is favored for higher-bandwidth systems using laser sources, while 62.5/125 has historical use with LED sources. The other core sizes aren’t the standard multimode options (25 μm is typical for single-mode fiber; 40, 60, 75, and 100 μm aren’t standard multimode core sizes).

In multimode fiber, the core diameter determines how many light paths (modes) can propagate and influences bandwidth and coupling. The two most common core diameters are 50 microns and 62.5 microns, which form the standard 50/125 and 62.5/125 fiber types. The 50/125 fiber is favored for higher-bandwidth systems using laser sources, while 62.5/125 has historical use with LED sources. The other core sizes aren’t the standard multimode options (25 μm is typical for single-mode fiber; 40, 60, 75, and 100 μm aren’t standard multimode core sizes).