Three Common Fiber Optic Connector Types

LC Connector: The LC connector was developed by the renowned Bell Research Institute, featuring a user-friendly modular jack (RJ) latch mechanism. The ferrule and sleeve dimensions are half of those used in standard SC, FC, etc., at 1.25mm, which increases the density of fiber optic connectors in optical distribution frames. Currently, LC-type connectors have become dominant in single-mode SFF applications, with rapidly growing use in multimode applications as well.

FC Fiber Optic Connector: This connector was originally developed by NTT in Japan. FC stands for Ferrule Connector, indicating that the external reinforcement uses a metal sleeve with a screw-type fastening mechanism. Early FC-type connectors used ceramic ferrules with flat contact end faces (FC). These connectors feature a simple structure, easy operation, and straightforward manufacturing, but the fiber end faces are sensitive to dust and prone to Fresnel reflection, making it difficult to improve return loss performance. Later, this connector type was improved by adopting spherical contact end faces (PC) for the ferrules while keeping the external structure unchanged, significantly enhancing insertion loss and return loss performance.

SC Fiber Optic Connector: This is a media converter (optical-electrical converter) developed by NTT Corporation in Japan. Its housing is rectangular, and the ferrule and coupling sleeve dimensions are identical to those of the FC type, with the ferrule end faces typically polished in PC or APC styles. The fastening mechanism uses a push-pull latch design that requires no rotation. This connector type offers low cost, convenient plug-in operation, minimal insertion loss fluctuation, high compressive strength, and high installation density.