The FC connector is a fiber-optic connector with a threaded body, which was designed for use in high-vibration environments. This article provides a deep dive into these connectors, their differences, polishing styles, applications, and comparisons with other less common connectors such. A fiber optic connector is a mechanical device used to align and join optical fibers, enabling light to pass through with minimal loss. What are the differences between them? Who is the most popular one? Find the answer in the article. Among them, FC, SC, ST and LC are applied commonly.