Allows only one mode of light to propagate in the core. It has a very thin central glass core (typically
8.5 or 9.5μm in diameter) and operates at wavelengths of 1310nm and 1550nm.
Single-mode fiber features low dispersion and low loss, suitable for long-distance and high-speed data transmission.
* Multi-mode Fiber:
Permits multiple modes of light to propagate in the core simultaneously.
The core diameter is generally 50μm/62.5μm, with standard wavelengths of 850nm and 1300nm. Multi-mode fiber is commonly used for short-distance and low-speed data transmission, such as in local area networks (LANs).
* By Refractive Index Distribution
* Step-index Fiber: The refractive indices of the core and cladding are uniform, with an abrupt change at their interface.
This fiber has a simple structure and is easy to manufacture but suffers from large modal dispersion, limiting its
transmission distance and bandwidth.
* Graded-index Fiber:
The refractive index of the core gradually decreases from the center to the edge in a graded
distribution. Graded-index fiber can effectively reduce modal dispersion, improve transmission performance,
and is often used in multi-mode fibers.
