The main factors that cause fiber attenuation are: intrinsic, bending, extrusion, impurity, non-uniformity and docking.
Intrinsic characteristic
It is the inherent loss of optical fiber, including: Rayleigh scattering, intrinsic absorption, etc.
Bending
When the fiber is bent, part of the light in the fiber will be scattered and lost, resulting in loss.
Squeeze
Loss caused by the small bending of an optical fiber when it is squeezed.
Impurity
The loss caused by the absorption and scattering of light propagating in the fiber by impurities within the fiber.
Non-uniformity
Loss caused by nonuniform refractive index of fiber material.
Docking
Optical fiber docking loss, such as: different axis (single mode fiber coaxiality is required to be less than 0.8μm), end face and axis is not perpendicular, end face is uneven, docking core diameter does not match and splicing quality is poor.
Artificial attenuation
In the actual work, sometimes it is necessary to carry out artificial fiber attenuation, such as optical communication system used in the debugging of optical power performance, calibration calibration of optical fiber instrument, fiber signal attenuation of fiber attenuator.
