What's that hairy stuff inside the fiber optic cable?

　　The "hair" inside the cable may actually refer to a special structure or addition inside the cable. Specifically, this may involve the following situations:

　　Tensile cable or reinforced core:

　　In some fiber optic cable structures, in order to improve the mechanical strength of the fiber optic cable, especially the tensile strength, one or more tensile wires or reinforced cores are built in. These tensile wires are usually made of high-strength materials such as steel wire or aramid fibers (also known as Kevlar fibers). They are designed to withstand the tensile forces that the fiber optic cable may encounter during laying and use, thus protecting the fiber inside the cable from damage. These tensile wires or reinforced cores may exhibit a fine filamentous appearance similar to "hair".

　　Filler or water barrier material:

　　The inside of a fiber optic cable may contain fillers or water-blocking materials in addition to fiber optics and tensile wires/reinforcing cores. The main role of these materials is to fill the voids inside the cable, prevent moisture and moisture from entering, and improve the cable's flexibility and bending resistance. In some cases, these fillers or water-blocking materials may exhibit a "hair" like appearance, but in reality they are made of different materials.

　　Special structure of optical cable:

　　Another possibility is that the fiber optic cable uses a special design structure, such as a capillary cable. The diameter of the capillary cable is very SMall, similar to the thickness of a hair. This type of cable is usually used in application scenarios that require a high degree of flexibility and a tiny diameter. However, it should be noted that the inside of the capillary cable still contains optical fibers and other necessary structural elements, rather than simple "hair".

　　To sum up, the "hair" like things carried inside the fiber optic cable may be tensile/reinforcing cores, fillers/water-blocking materials, or part of a specially structured fiber optic cable. These elements are all necessary for the cable to function properly and protect the fiber from damage. When identifying these elements, their appearance, material and function should be carefully distinguished to ensure a correct understanding of the cable structure.