What are the most common multimode core diameters?

What are the most common multimode core diameters?

• A. 9 µm and 125 µm
• B. 50 µm and 125 µm
• C. 50, 62.5
• D. 62.5 µm and 125 µm

Answer: (C)

Two core diameters dominate multimode fiber: 50 μm and 62.5 μm. These are the standard core sizes used in common multimode cables, paired with a 125 μm cladding to form 50/125 and 62.5/125 fibers. The 125 μm value refers to the cladding, not the core, so it doesn’t represent a multimode core diameter. The 9 μm diameter is typical for single-mode fiber, so it doesn’t fit with multimode cores. That’s why the two most common multimode core diameters are 50 and 62.5 μm.

Two core diameters dominate multimode fiber: 50 μm and 62.5 μm. These are the standard core sizes used in common multimode cables, paired with a 125 μm cladding to form 50/125 and 62.5/125 fibers. The 125 μm value refers to the cladding, not the core, so it doesn’t represent a multimode core diameter. The 9 μm diameter is typical for single-mode fiber, so it doesn’t fit with multimode cores. That’s why the two most common multimode core diameters are 50 and 62.5 μm.