Optical Fibers

Abstract

Optical fibers are dielectric waveguides that transport light between two points. They are usually made of high-purity glasses. It is well known that light travels in a straight line in free space but when light is trapped in an optical fiber, it can propagate with bends and can carry information anywhere from a few meters to thousands of kilometers. This property of optical fibers has driven the fabrication of low-loss optical fibers for telecommunication applications. Nowadays, optical fibers are used in many other fields such as lasers, amplifiers, and sensing. This chapter is organized as follows: In the first part, fundamentals of light guiding in optical fibers will be given. In the second part, after a brief presentation of the fabrication process of optical fibers, some properties of optical fibers such as attenuation, dispersion, polarization effects, and nonlinearities will be presented. In the third part, some types of specialty optical fibers will be described, in particular rare-earth-doped fibers, photonic crystal fibers, nonsilica fibers, and fiber Bragg gratings. Finally, in the fourth part, a focus will be put on some usual applications of optical fibers, in particular for telecommunications, amplifiers, lasers, and sensing.