What is the fiber optic connector on the optical module called

The fiber optic connector on most modern optical modules, such as SFP or QSFP transceivers, is typically an LC connector.

Overview

The fiber optic connector on an optical module serves as the physical interface that links the transceiver to fiber optic cables, enabling optical signal transmission between network devices. It does not determine the module's speed or protocol but ensures precise alignment of the fiber core with the optical transmitter and receiver, which is essential for minimizing insertion loss and maintaining signal quality. Common Connector TypesLC (Lucent Connector): The most widely used connector on modern SFP and QSFP modules.

It features a 1. 25 mm ferrule and a push-pull latch, supporting high port density and duplex channels in a compact form factor.

L

C connectors are standard for data centers and high-density networking environments.

S

C (Subscriber Connector): A 2. 5 mm ferrule with a square snap-in housing, commonly found in legacy networks and some industrial applications.

S

C connectors are less common on new SFP modules but still used in existing infrastructure. MPO/MTP (Multi-Fiber Push-On / Multi-Fiber Termination Push-On): Used for high-density cabling and backbone connections rather than directly on standard SFP modules. These connectors support multiple fibers in a single interface, ideal for 40G/100G deployments.

Function and Importance

The connector ensures that light from the optical module is efficiently coupled into the fiber, reducing reflection and insertion loss. Proper connector selection is critical for network performance, as mismatched connectors require adapters and can increase operational complexity. Most connectors are spring-loaded to maintain contact pressure and precise alignment when mated.

Summary

In modern optical modules, LC connectors are the default choice, while SC connectors appear in legacy systems, and MPO/MTP connectors are used for high-density multi-fiber applications. Selecting the correct connector type ensures compatibility with patch cables, minimizes signal loss, and supports efficient network deployment.