What is the difference between multimode and singlemode fiber?
A mode is a ray of light that is transmitted through a fiber optic cable.
Singlemode fibers have cores of a relatively small diameter compared to the fiber’s cladding and jacket, and allow only one mode of light to propagate. The light signal is subject to fewer reflections as it propagates through the fiber, and consequently suffers fewer losses. This type of fiber is used for high-bandwidth, long-distance communication, on the order of tens to hundreds of kilometers in length.
Multimode fibers have relatively large diameter cores – 125μm to 1000μm – that allow for multiple modes of light to propagate through. Due to its larger diameter, POF is exclusively multimode.
References
(2014) The FOA Reference For Fiber Optics – Optical Fiber [Online]. Available: http://www.thefoa.org/tech/ref/basic/fiber.html
A. Weinert., Plastic Optical Fibers. Munich, Germany: Publicis MCD Verbeagentur GmbH, 1999.