The inherent advantages of dispersion-modified single-mode (SM) fibers, i.e., potential matching of the zero in dispersion to the lowest-loss window at 1.55 μm or low dispersion over an extended wavelength range, initiated remarkable development of new single-mode designs in the past. For several reasons—especially the uncertainty in the system’s final operating wavelength and some restrictions remaining in the theoretical prediction of adequately optimized single-mode structures—a large variety of profiles have been prepared by different CVD techniques.1–5 Additionally, the optical parameters relevant for system applications, such as dispersion, optical loss, bending sensitivity, coupling and splicing performance, turn out to be closely but differently correlated to the specific profile design used. This somewhat confusing situation has led to a crude first-order classification of these modified single-mode structures into either dispersion-shifted (DS) or dispersion- flattened (DF) profile designs (see Fig. 1). The basic design criteria and optical properties of such second-generation DS and DF fibers are reviewed and compared to the corresponding data of typical first-generation matched clad (MC) and depressed clad (DC) single-mode fibers.
© 1988 Optical Society of AmericaPDF Article