Fiber optic connectors are categorized by fiber mode, fiber count, and connector style, with common types including SC, LC, ST, FC, MTP, and MPO.

Classification by Fiber Mode

Fiber optic connectors are primarily divided into single-mode and multimode types. Single-mode connectors are designed for long-distance transmission with a small core diameter, minimizing signal loss and dispersion. Multimode connectors have a larger core, suitable for shorter distances and higher bandwidth applications in data centers and local networks .

Classification by Fiber Count

Connectors can also be categorized based on the number of fibers they support:

• Single-fiber connectors: Connect one fiber per connector, such as SC, LC, ST, and FC .
• Duplex connectors: Pair two fibers for simultaneous transmit and receive, commonly used in SC and LC duplex configurations .
• Multi-fiber connectors: Support multiple fibers in a single connector, such as MTP and MPO, ideal for high-density applications in modern data centers .

Classification by Connector Style

Connector style refers to the physical design and coupling mechanism:

• SC (Subscriber Connector): Square push-pull design, widely used in FTTH and data centers, available in SC/APC for low return loss .
• LC (Lucent Connector): Miniaturized version of SC with a 1.25mm ferrule, suitable for high-density applications .
• ST (Straight Tip): Bayonet-style twist-lock, used in legacy and industrial networks .
• FC (Ferrule Connector): Threaded coupling, secure in high-vibration environments like factories and railways .
• MTP/MPO: Multi-fiber connectors for high-density cabling, supporting 12, 24, or more fibers in a single interface .

Additional Considerations

Connectors are also evaluated by insertion loss and return loss, which measure signal attenuation and reflection. Choosing the right connector depends on fiber type, transmission distance, network density, and environmental conditions . Modern networks favor small, simple, and multi-fiber connectors to maximize port density and maintain high performance . In summary, fiber optic connectors are categorized by fiber mode (single-mode vs. multimode), fiber count (single, duplex, multi-fiber), and connector style (SC, LC, ST, FC, MTP/MPO), with each type optimized for specific applications and network requirements.