Fiber Optic Cable Differences and Fiber Optic Connector Introduction

An optical fiber is a medium that transmits information from one end to another. It is a glass or plastic fiber that serves as a transmission medium for information to pass through.

    Often, the terms "optical fiber" and "optical cable" are confused. Most optical fibers must be covered by several layers of protective structure before use, and the covered cable is called an "optical cable." The protective structure on the outer layer of the optical fiber prevents damage from the surrounding environment, such as water, fire, electric shock, etc. The optical cable consists of: the optical fiber, buffer layer, and jacket. An optical fiber is similar to a coaxial cable, except that it has no mesh shielding layer. The center is a glass core through which light propagates. In multimode fiber, the core diameter is 15mm50mm, roughly equivalent to the thickness of a human hair. The core diameter of single-mode fiber is 8mm10mm. Surrounding the core is a glass cladding with a lower refractive index than the core, to keep the light within the core. Further outside is a thin plastic coating used to protect the cladding. Optical fibers are usually bundled together and protected by an outer sheath. The fiber core is typically a double-layer concentric cylindrical body with a very small cross-sectional area made of quartz glass. It is brittle and prone to breakage, so an additional protective layer is required.

  Fiber Optic Connector Types
    FC: Round with thread (most commonly used on distribution frames)
    ST: Snap-in round type
    SC: Snap-in square type (most commonly used on routers and switches)
    PC: Micro-spherical grinding and polishing
    APC: Polished at an 8-degree angle with micro-spherical grinding and polishing
    MT-RJ: Square type, dual-fiber transmit/receive integrated on one end

Fiber Optic Connectors

    Fiber optic connectors are devices that enable detachable (removable) connections between optical fibers. They precisely align the two end faces of optical fibers so that the optical energy output from the transmitting fiber can be maximally coupled into the receiving fiber, and the impact on the system caused by their insertion into the optical link is minimized. This is the basic requirement of fiber optic connectors. To a certain extent, fiber optic connectors also affect the reliability and various performance aspects of optical transmission systems.
    Fiber optic connectors can be classified by transmission medium into common silica-based single-mode and multimode connectors, as well as other connectors using plastic or other media for transmission. By connector structure type, they can be divided into FC, SC, ST, LC, D4, DIN, MU, MT, and other forms. Among them, ST connectors are typically used on cabling equipment ends, such as fiber distribution frames and fiber optic modules, while SC and MT connectors are typically used on network equipment ends. By fiber end face shape, they are classified as FC, PC (including SPC or UPC), and APC. By fiber core count, they are divided into single-core and multi-core (such as MT-RJ). Fiber optic connectors are widely used and come in many varieties. In practical applications, we generally distinguish them according to the different structures of fiber optic connectors.