Lc is a small square tail fiber

The LC (Lucent Connector) is a compact fiber optic connector with a small square body and a 1. 25 mm ferrule, ideal for high-density applications.

Physical Characteristics

The L

C connector features a miniaturized square body with a 1. 25 mm ceramic or zirconia ferrule, which is half the diameter of traditional SC, ST, or FC ferrules. Its small form factor allows for approximately twice the port density compared to SC connectors in the same rack space.

The connector uses a push-pull latch mechanism, similar to an RJ-45 clip, providing secure and easy insertion and removal. ApplicationsLC connectors are widely used in data centers, high-density patch panels, and SFP/SFP+/SFP28 and QSFP transceiver interfaces. They are particularly suited for duplex or simplex configurations and behind-the-wall (BTW) modules, making them a standard choice for modern telecom and enterprise networks.

Their compact size and low insertion loss make them ideal for environments where space and port density are critical.

Performance

Typical insertion loss for LC connectors ranges from 0. 10–0. 20 dB, and return loss is UPC ≥ −55 dB or APC ≥ −65 dB.

These specifications ensure high signal integrity and minimal light reflection, which is essential for high-speed optical transmission. Comparison to Other ConnectorsSC Connector: Larger square body, 2. 5 mm ferrule, push-pull design, lower port density.

S

T Connector: Round body, bayonet twist-lock, legacy systems.

F

C Connector: Round metal body, threaded coupling, high-vibration environments. In summary, the LC connector is indeed a small square tail fiber, designed for compact, high-density, and reliable optical connections in modern networking systems.