singlemode fiber question FREE cabling and networking Helpdesk
 Question by scott parks posted 24 Feb 2004
 singlemode fiber question
What are the disserences in singlemode vs multimode fiber?

 Answer by Dmitri Abaimov posted 25 Feb 2004
Dear Scott,

In couple words:

There is a big difference in the diameter of the core, the actual path of the light. Singlemode fiber has much smaller core that only allows a single mode (or a single light ray or wave) to propagate. This allows for less dispersion of the signal and, therefore, higher data rates and greater distances. The downsize of the singlemode fiber is the fact that, due to the small size of the core, big portion of the light's energy is lost before the light even enters the fiber. This leads to higher energy light sources that are more expensive themselves and require more complex and expensive control circuitry.
Multimode fiber on the other hand, has much greater core diameter, which allows for better coupling of the light energy. That makes it possible to use cheaper light sources. The downsize is: it is prone to signal dispersion. This limits both speed and distance at which multimode fiber can be deployed.

Dmitri Abaimov, RCDD

Click here to see the expert's profile
Back to the current page of questions | Back to all the questions
Back to HELPDESK | Ask your question
Residential Cabling Guide

Home Cabling Guide

Finally, an instantly downloadable book that saves you thousands in home improvement dollars! Enjoy living in 21st century technology-advanced home while increasing its selling value and competitive advantage on the real estate market. Whether your cabling is for home office or high-tech leisure, you can wire your home yourself or learn "wirish" to speak with your cabling contractors in their language!

Learn more ...