Multimode fiber parameters om3

OM3 multimode fiber is a 50/125 µm laser-optimized fiber designed for high-speed data transmission up to 10, 40, and 100 Gbps over short to medium distances.

Core and Cladding

OM3 fiber has a 50 µm core diameter and a 125 µm cladding diameter, following the graded-index multimode fiber design. This smaller core compared to older OM1/OM2 fibers allows for better modal dispersion control and improved performance with laser sources like VCSELs .

Wavelength and Light Source

OM3 is optimized for 850 nm wavelength operation, which is standard for vertical-cavity surface-emitting lasers (VCSELs). It can also operate at 1300 nm, though 850 nm is the primary wavelength for high-speed LAN and data center applications .

Bandwidth and Modal Performance

OM3 fiber is laser-optimized multimode fiber (LOMMF) with a minimum modal bandwidth of 2000 MHz·km at 850 nm under overfilled launch (OFL) conditions. This high bandwidth supports 10 Gbps Ethernet up to 300 meters, and emerging 40/100 Gbps Ethernet up to 100 meters .

Maximum Transmission Distance

• 10 Gbps Ethernet: up to 300 meters
• 40/100 Gbps Ethernet: up to 100 meters OM3 is fully compatible with legacy OM2 installations, but OM4 is recommended for longer distances or higher performance requirements .

Jacket Color and Standards

OM3 fiber typically has an aqua-colored jacket for easy identification. It complies with TIA-492AAAC and IEC 60793-2-10 standards for laser-optimized multimode fibers .

Applications

OM3 is widely used in:

• Data centers for 10/40/100 Gbps Ethernet
• Enterprise LANs for high-speed backbone connections
• Short-reach interconnects where cost-effective multimode fiber is preferred over single-mode fiber .

Comparison with OM4 and OM5

• OM4: Higher modal bandwidth (4700 MHz·km at 850 nm), longer distances for 40/100 Gbps Ethernet (up to 150 m)
• OM5: Supports short wavelength division multiplexing (SWDM) across 850–950 nm, enabling multiple wavelengths over a single fiber for 40/100 Gbps applications . OM3 remains the minimum recommended fiber for new LAN and data center installations, balancing cost and performance for most short-reach high-speed applications .