What’s the Difference: Single Mode vs Multimode Fiber?

An optical fiber is a flexible, transparent fiber made of extruded glass or plastic, slightly thicker than a human hair. Optical fibers are used most often as a means to transmit light between the two ends of the fiber and find wide usage in fiber-optic communications, where they permit transmission over longer distances and at higher bandwidths than wire cables. Optical fibers typically include a transparent core surrounded by a transparent cladding material with a lower index of refraction. Light is kept in the core by the phenomenon of total internal reflection which causes the fiber to act as a waveguide. In general, there are two kinds of optical fiber: fibers that support many propagation paths or transverse modes are called multimode fibers (MMF), while those that support a single mode are called single mode fibers (SMF). Single mode vs multimode fiber: what’s difference between them? Reading this text will help you get the answer.

Single Mode vs Multimode Fiber: What’s single mode optical fiber?

In fiber-optic communication, a single mode optical fiber (SM) is an optical fiber designed to carry light only directly down the fibre – the transverse mode. For single mode optical fiber, no matter it operates at 100 Mbit/s or 1 Gbit/s date rates , the transmission distance can reach to at least 5 km. Typically, it is used for long-distance signal transmission.

Single Mode vs Multimode Fiber: What’s multimode optical fiber?

Multimode optical fiber(MM) is a type of optical fiber mostly used for communication over short distances, such as within a building or on a campus. Typical transmission speed and distance limits are 100 Mbit/s for distances up to 2 km (100BASE-FX), 1 Gbit/s up to 1000m, and 10 Gbit/s up to 550 m. There are two kinds of multimode indexes: step index and graded index.

What’s difference between single mode optical fiber and multimode?

Attenuation: The attenuation of multimode fiber is higher than SM fiber because of its larger core diameter. The fiber core of single mode cable is very narrow, so the light that passes through these fiber optical cables is not reflected too many times, which keeps the attenuation to a minimum.

Core diameter: The main difference between multimode and single mode fiber is that the former has much larger core diameter, typically has a core diameter of 50 or 62.5 µm and a cladding diameter of 125 µm. While a typical single mode fiber has a core diameter between 8 and 10 µm and a cladding diameter of 125 µm.