1. Optical fiber manufacturing:
At present, optical fiber manufacturing methods mainly include: intra-tube CVD (chemical vapor deposition), in-rod CVD, PCVD (plasma chemical vapor deposition) and VAD (axial vapor deposition).
2. Fiber attenuation:
The main factors causing fiber attenuation are: intrinsic, bending, extrusion, impurities, unevenness and docking.
Intrinsic: It is the inherent loss of fiber, including: Rayleigh scattering, intrinsic absorption, etc.
Bending: Loss caused by scattering of light in some of the fibers when the fiber is bent.
Extrusion: Loss caused by tiny bends in the fiber when it is squeezed.
Impurities: Impurities in the fiber that absorb and scatter light propagating in the fiber.
Unevenness: Loss due to uneven refractive index of the fiber material.
Docking: Loss caused by fiber optic docking, such as: different axes (single mode fiber coaxiality requirements less than 0.8μm), end face and axis are not perpendicular, end face is not flat, butt diameter mismatch and poor weld quality.