ABSTRACT
Multicomponent Glass . . . . . . . . . . . . . . . . . . . . . . . . . .298 12.3.2 Fiber Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299
12.4 Overview of Key Special Optical Fibers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302 12.4.1 Infrared Fibers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302 12.4.2 Polarization Maintaining Fibers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305 12.4.3 Polymer Optical Fibers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307 12.4.4 Optical Fiber Microtapers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308 12.4.5 Microstructured Optical Fibers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310 12.4.5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310 12.4.5.2 Fabrication of MOFs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311 12.4.5.3 Endlessly Single-Mode Fibers and Modal Control . . . . . . . . 312 12.4.5.4 Properties of Small-Core Index-Guiding MOFs . . . . . . . . . . . 312 12.4.5.5 Birefringent MOFs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315 12.4.5.6 Photonic Bandgap and Hollow-Core MOFs . . . . . . . . . . . . . . 315 12.4.6 Multimaterial Microstructured Fibers . . . . . . . . . . . . . . . . . . . . . . . . . . . 320
12.5 Conclusions and Future Outlook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
12.1 Introduction Optical bers are the cornerstone of the global telecommunication revolution in the twentieth century leading to the advent of the digital age, as is testied by the Nobel Prize for Physics awarded to Charles Kao in 2009 (Kao 2010). e development of ultralow-loss optical bers in the 1970s was arguably the most critical milestone among a series of groundbreaking developments, including the invention of the semiconductor laser and that of the erbium-doped optical amplier (Mears et al. 1987), which have opened up the possibility for long-distance transmission of data at unprecedented rates and huge capacity. More recently, advances in rare-earth-doped optical bers have enabled the development of multikilowatt ytterbium-doped ber lasers that are revolutionizing the industrial materials processing sector (Richardson et al. 2010). An historical account on the development of optical bers from the outset until recent activity can be found in Gambling (2000).
