Fiber Optic Tutorials

This is a continuation from the previous tutorial - specialty single-mode fibers.   Applying a sinusoidal signal to a collection of atoms, with the frequency \(\omega\) tuned near one of the atomic transition frequencies \(\omega_a\), will produce a coherent induced polarization \(p(t)\) or \(\tilde{P}(\omega)\) in the collection of atoms. The strength of this induced response will be proportional to the instantaneous population difference \(\Delta{N}\) on that particular transition. At the same time, however, this applied signal field will also cause the populations \(N_1(t)\) and \(N_2(t)\) in the collection of atoms to begin changing slowly because of stimulated transitions between the two levels...

This is a continuation from the previous tutorial - polarizing beam-splitter prisms.   1. Introduction The last two decades of the twentieth century saw an immense increase in the number of applications in which optical fibers of different kinds were used. The explosive development of fiber optics for communication was a major driving factor behind this progress, providing the necessary tools and enabling technologies. Contrary to popular belief, however, the development of the optical fiber was not initially driven by the needs of the communications sector but has a much longer history. For instance, the ‘‘controlled’’ guiding of light in...

This is a continuation from the previous tutorial - Nicol-type prisms.   The three classic polarizing beam-splitter prisms are the Rochon, Sénarmont, and Wollaston, shown in perspective in Fig. 10a to c and in side view in Fig. 11a to c. In addition, any polarizing prism can be used as a polarizing beam splitter by changing the shape of one side and removing the absorbing coating from its surface. Two examples of such prisms are the Foster prism, in which the ordinary and extraordinary rays emerge at right angles to each other, and the beam-splitting Glan-Thompson prism, in which the ordinary...

This is a continuation from the previous tutorial - an introduction to the fundamentals of coherent fiber optic transmission technology.   Nicol-type prisms are not generally used at the present time, as Glan types are optically preferable. However, they were the first kind made and were once so common that Nicol became a synonym for polarizer. There is much more calcite wastage in making Glan-type prisms than in making the simpler Nicol types so that, even though Glan polarizers were developed in the nineteenth century, it was only following the recent discoveries of new calcite deposits that they became popular....

This is a continuation from the previous tutorial - electric-dipole transitions in real atoms.   1. High-Capacity Fiber Transmission Technology Evolution Since the first demonstration of an optical fiber transmission system in 1977, the demands for higher capacity and longer reach have always been the dominant driver behind the evolution of this new communication technology. In less than four decades, single-fiber transmission capacity has increased by more than five orders of magnitude, from the early 45 Mb/s, using direct modulation and direct detection, to more than 8.8 Tb/s by using the digital coherent optical transmission technology. In the meantime, optical...