How Are The Optical Fibers in Optical Cables Manufactured? What Are The Key Steps in Its Manufacturing Process?

The manufacturing process of optical fibers in optical cables is a complex and precise technical process, which mainly includes the following key steps:
Raw material preparation: The main raw material for optical fibers is high-purity silica (silica sand). Firstly, silica sand needs to be refined and purified to ensure its extremely high purity, in order to eliminate the impact of impurities on the performance of optical fibers.
Prefabricated rod manufacturing: In the process of manufacturing prefabricated rods, chemical vapor deposition (CVD) or external vapor deposition (OVD) methods are used to convert purified silica into a glassy state and gradually form the core rod of the optical fiber. This step requires precise control of parameters such as temperature, pressure, and gas flow to ensure the quality and dimensional accuracy of the prefabricated rod.
Fiber optic drawing: After the prefabricated rod is manufactured, it is placed in a drawing tower and heated to soften at high temperatures. Subsequently, by precisely controlling temperature and speed, the softened preform was pulled into slender optical fibers. During the drawing process, the diameter and structure of the optical fiber will change, forming a fiber with a specific refractive index distribution.
Coating and coating: The drawn optical fiber is very thin and prone to breakage, so a protective layer needs to be coated on its surface to increase its mechanical strength. Coating materials are usually plastic or resin. After coating, the optical fiber also needs to undergo plastic coating treatment, that is, adding a protective sleeve on the outside of the optical fiber to protect it from external environmental damage.
Testing and screening: After coating and coating, the optical fiber needs to undergo a series of rigorous tests, including refractive index testing, strength testing, and attenuation testing, to ensure that its performance meets the standards. Only fiber optic cables that pass the test will be selected as the final product.
Packaging and transportation: The tested optical fibers are packaged into optical cables, and this process needs to consider factors such as protecting the optical fibers, facilitating transportation and use. Fiber optic cables are usually wound on protective reels and placed in appropriate packaging boxes for transportation and storage.
Throughout the manufacturing process, it is necessary to strictly control various parameters and processes, such as temperature, pressure, gas flow rate, stretching speed, and coating thickness, to ensure the quality and performance of optical fibers. In addition, multiple quality inspections and controls are required during the manufacturing process to ensure the reliability and consistency of the final product.
Overall, the manufacturing of optical fibers in optical cables is a high-tech process that requires precise control of various parameters and processes to ensure the performance and quality of the final product.