Multimode Fiber vs. Single Mode Fiber

Attribute	Multimode Fiber	Single Mode Fiber
Core Diameter	Larger (50 or 62.5 microns)	Smaller (9 microns)
Bandwidth	Higher	Lower
Distance	Shorter	Longer
Cost	Lower	Higher
Light Source	LED	Laser

Introduction

When it comes to fiber optic cables, there are two main types that are commonly used: multimode fiber and single mode fiber. Both types have their own unique attributes and are suitable for different applications. In this article, we will compare the characteristics of multimode fiber and single mode fiber to help you understand the differences between the two.

Core Size

One of the key differences between multimode fiber and single mode fiber is the size of their core. Multimode fiber typically has a larger core size, usually around 50 to 62.5 microns. This larger core allows for multiple modes of light to travel through the fiber at the same time, hence the name "multimode." On the other hand, single mode fiber has a much smaller core size, typically around 9 microns. This smaller core size allows for only a single mode of light to travel through the fiber, hence the name "single mode."

Bandwidth and Distance

Due to the larger core size of multimode fiber, it has a higher bandwidth compared to single mode fiber. This means that multimode fiber can carry more data over shorter distances at higher speeds. Multimode fiber is typically used for shorter distance applications, such as within buildings or campuses. Single mode fiber, on the other hand, has a lower bandwidth but can transmit data over much longer distances. Single mode fiber is commonly used for long-haul telecommunications and data center connections.

Light Source

Another difference between multimode fiber and single mode fiber is the type of light source used to transmit data. Multimode fiber is typically used with LED light sources, which are less expensive and easier to work with. LED light sources emit a larger beam of light, which is suitable for the larger core size of multimode fiber. Single mode fiber, on the other hand, is typically used with laser light sources, which have a much narrower beam of light that is better suited for the smaller core size of single mode fiber.

Cost

When it comes to cost, multimode fiber is generally less expensive than single mode fiber. This is due to the larger core size of multimode fiber, which is easier to manufacture and work with. In addition, the LED light sources used with multimode fiber are also less expensive than the laser light sources used with single mode fiber. However, despite the higher cost, single mode fiber is often preferred for long-distance applications due to its higher bandwidth and lower attenuation.

Attenuation

Attenuation refers to the loss of signal strength as it travels through the fiber optic cable. Single mode fiber has lower attenuation compared to multimode fiber, which means that it can transmit data over longer distances without losing signal strength. This is due to the smaller core size of single mode fiber, which allows for less dispersion of the light signal. In contrast, multimode fiber has higher attenuation, which limits its transmission distance and makes it more suitable for shorter distance applications.

Conclusion

In conclusion, both multimode fiber and single mode fiber have their own unique attributes that make them suitable for different applications. Multimode fiber is ideal for shorter distance applications where cost is a factor, while single mode fiber is preferred for long-haul telecommunications and data center connections. Understanding the differences between these two types of fiber optic cables can help you choose the right one for your specific needs.