What does "splice closure" refer to in fiber optics?

A splice closure refers to a protective enclosure used to house and protect the splices of fiber optic cables. When fiber optic cables are joined together—either for extending the length of a network or connecting different components—splice closures provide a secure environment for these connections. These closures are designed to shield the splices from environmental factors such as moisture, dust, and physical damage, ensuring the integrity and performance of the optical connection over time. Properly installed splice closures help maintain signal quality and can contribute significantly to the longevity of a fiber optic network.

In the context of the other choices, a type of fiber optic cable is not correct because "splice closure" does not describe a cable itself. A method of connecting fibers refers to the process of splicing but does not encompass the protective aspect that closures provide. Lastly, while tools for testing fiber optics are essential for installation and maintenance, they do not relate to the concept of splice closures, which are specifically focused on the protection of splices rather than testing or connection methods.