Special optical fiber failure classification and solution

Optical fibers are widely used in various communication and sensing applications due to their ability to transmit signals over long distances with low attenuation and high bandwidth. However, optical fibers are prone to various types of failures that can affect their performance and reliability. In this article, we will discuss the different types of optical fiber failures, their causes, and the solutions to mitigate or prevent them.

Mechanical Failures

Mechanical failures are the most common type of optical fiber failure, and they occur due to the physical damage of the fiber. The mechanical failures can be categorized into two types: macrobending and microbending.

a) Macrobending

Macrobending occurs when the optical fiber is bent beyond its minimum bend radius. This can happen during installation, maintenance, or due to external factors such as vibration or pressure. When the fiber is bent, the light inside the fiber experiences loss, which can cause signal degradation or complete signal loss. The solution to prevent macrobending is to ensure that the minimum bend radius is not exceeded during installation or maintenance. Additionally, protective measures such as cable ties, clamps, or ducts can be used to prevent the fiber from bending excessively.

b) Microbending

Microbending is caused by small-scale deformations in the fiber due to external factors such as vibration, temperature changes, or pressure. These deformations cause microscopic variations in the refractive index, which can scatter or absorb light, resulting in signal loss. The solution to prevent microbending is to ensure that the fiber is properly supported and protected from external factors. Additionally, buffer tubes or jackets can be used to provide additional protection to the fiber.

Environmental Failures

Environmental failures are caused by the exposure of the optical fiber to harsh environmental conditions such as high temperature, humidity, or corrosive substances. These conditions can cause the fiber to deteriorate or degrade, resulting in signal loss or complete failure.

a) Temperature

High temperature can cause the optical fiber to expand, which can lead to stress and deformation in the fiber. This can cause signal attenuation or complete signal loss. The solution to prevent temperature-related failures is to use fiber cables with a high-temperature rating and to ensure that the fiber is properly installed and protected from high-temperature sources.

b) Humidity

High humidity can cause the optical fiber to absorb moisture, which can affect the optical properties of the fiber. This can cause signal degradation or complete signal loss. The solution to prevent humidity-related failures is to use fiber cables with a water-resistant coating or jacket and to ensure that the fiber is properly installed and protected from moisture.

c) Corrosion

Optical fibers can be corroded when exposed to corrosive substances such as acids or alkalis. Corrosion can cause the fiber to weaken, resulting in signal attenuation or complete signal loss. The solution to prevent corrosion-related failures is to use fiber cables with a corrosion-resistant coating or jacket and to ensure that the fiber is not exposed to corrosive substances.

Optical Failures

Optical failures are caused by the inherent properties of the fiber itself. These failures can occur due to manufacturing defects or material impurities.

a) Attenuation

Attenuation is the loss of signal strength as the signal travels along the fiber. Attenuation can be caused by various factors such as absorption, scattering, or bending losses. The solution to prevent attenuation-related failures is to use high-quality fiber with low attenuation and to ensure that the fiber is properly installed and protected from external factors.

b) Dispersion

Dispersion is the spreading of the signal pulse as it travels along the fiber. Dispersion can be caused by various factors such as material impurities or manufacturing defects.