Optical Fiber Types

Single-mode and multimode fibers — OM1–OM5, OS1/OS2 — wavelengths and typical distances.

Reference Reference Updated Apr 19, 2026
Reference

Fiber types

Type Core / cladding (µm) Color (jacket) Typical wavelength 10G reach 40G reach 100G reach
OM1 62.5 / 125 Orange 850 / 1300 nm 33 m
OM2 50 / 125 Orange 850 / 1300 nm 82 m
OM3 50 / 125 Aqua 850 nm (VCSEL) 300 m 100 m 100 m (SR4)
OM4 50 / 125 Aqua / Violet 850 nm 400 m 150 m 150 m
OM5 50 / 125 Lime green 850 – 950 nm 400 m 440 m (SWDM4) 150 m (SR4) / 400 m (SWDM4)
OS1 8–10 / 125 Yellow 1310 / 1550 nm 10 km 10 km 10 km
OS2 8–10 / 125 Yellow 1310 / 1550 nm 40 km 40 km 80 km+

Differences

Multimode (OM)
Larger core, LED or VCSEL source, shorter distances — cheaper per meter
Single-mode (OS)
Tiny core (~9 µm), laser source, long distances — more expensive optics
Modal dispersion
Multimode only — limits bandwidth-distance product
Wavelength
850 nm for VCSEL MMF, 1310/1550 nm for SMF

Connectors

Connector Notes
LC Small-form-factor, duplex — modern default
SC Square, push-pull — older but still common
ST Bayonet — legacy multimode
FC Threaded — labs, test equipment
MPO/MTP Multi-fiber ribbon — 12/24/32 fiber — used for 40G/100G/400G parallel optics