Optical connectors connect network devices to each other at data centers. They also connect fiber optic cables to customer equipment. Connectors attach to the ends of fiber optic cables. While there are many connectors on the market, SC and LC connectors are two common connector options. However, there are several important differences between them that you’ll want to consider.
Subscriber Connectors (SC) have a push-pull coupling end face with a spring-loaded ceramic ferrule plus a locking tab that secures the cable. This “square connector’s” time-tested “stick and click” winning design enables highly accurate alignment. SC connectors have been used in the industry since the mid-1980s when Nippon Telegraph and Telephone (NTT) laboratories developed them. This was not long after ceramic ferrules were invented. The SC connector was created for Gigabit Ethernet networking but was standardized in 1991 for telecommunication uses. Manufacturing costs came down, and the popularity of SC connectors grew.
Lucent Connectors (LC), also called “little connectors,” have not been on the scene very long. L C fiber connectors are push-pull connectors that are kept in place by a latch that secures the wire. When these “push and latch” connectors are inserted into devices, they can transfer data through a light beam. Transmitting only one beam of light, LC connectors are used with small-diameter single-mode fiber cables.
Their introduction was met with high license fees from Lucent Corporation, the inventor of the LC connector. Complicating matters, LC connectors cost more than SC connectors do. That’s because the LC connector’s complicated and detailed design drives up manufacturing costs. However, LC connectors overcame the license fee problem. They also gained traction in the industry, despite their comparatively high cost.
Both connectors feature a ceramic ferrule, which is a miniature tube that protects fibers if they become exposed or stripped. LC connectors have a 1.25mm ferrule, while the ferrule in SC connectors is twice as large, measuring 2.5mm. The relatively large size of SC connectors makes SC connectors unusable for some of today’s applications. The small ferrule in the LC connector makes the LC a small connector. The much smaller “footprint” of the LC is due to a compact ferrule and connector housing. The connection density this allows will continue to be a major factor when selecting connectors for next-generation IT applications.
There are more than a dozen fiber optic connectors that serve WANs, SANs, LANs, cellular base stations, fiber-to-the-x (FTTX) networks, CATV networks, telecom switching offices, cellular base stations, data centers, and test and measurement systems. However, LC and SC fiber optic connectors are the most popular options. That’s because of their relatively moderate cost, ruggedness, and their reliable, optically smooth and precisely-aligned connections.
Originally just used in Gigabit Ethernet networking, SCs are now also used for datacoms and telecoms applications. This includes point-to-point and passive optical networking. You’ll need SC connectors to connect fiber optic cables to your computer, wi-fi router, gaming console and other things. SC connectors suit applications that are sensitive to loss and demand high-precision signals. If you must fit several connectors into a small space or if you have a data center, LC connectors are what you need. Recently-introduced LC-compatible transceivers and active networking components will ensure a continuing increase in demand for LC connectors.
Performance and Reputation
SC connectors, also called “square connectors” and “standard connectors,” have always been easy to use. They’ve also always performed very well. In fact, after 30+ years in use, the SC connector is still the second most common connector used for polarization maintaining applications. LC connectors are not as effective as SC connectors, but they are necessary for some uses. Both connectors are fast and durable, though, and their insertion and return loss capabilities are the same. Additionally, both connectors can efficiently and safely transmit data between large, complex interconnected databases.
Fiber cables enable networks to accommodate increasing demands for higher bandwidth. Cables must have suitable connectors for the intended applications. SC connectors have been around for decades and remain popular for particular applications. However, optical fiber transmission technology continues to evolve, resulting in a viable market for LC connectors.