It was only about five years ago that the birth of the World Wide Web made the Internet user-friendly and accessible to anyone with a PC and phone line. Since then, the global communications infrastructure has struggled to keep pace with the rapidly increasing demand for bandwidth. But instead of bringing the infrastructure to its knees, this demand has created a feverish market for optoelectronic communications equipment and spurred much imaginative R&D around existing fiberoptic networks.
Wavelength-division multiplexing (WDM), for example, has become more common because it can allow service providers to stay abreast of this demand by piggybacking onto installed hardware. And the intensity of WDM development is the driving force behind much other related R&D, including new sources (see p. 56), new components (see p. 267 and p. 243), and more-sophisticated measurement equipment (see p. 203). Such developments have been prominent in the recent pages of Laser Focus World, so it should come as no surprise that the three plenary sessions at this year`s Conference on Lasers and Electro-Optics (CLEO `99) in Baltimore, MD, all address aspects of the communications explosion and its consequences within the world of optoelectronics. Communications is far from the only hot topic at CLEO, though, as evidenced by the growing diversity of optoelectronics R&D showcased at this year`s meeting (see p. 127).
There are other routes to light-based communications besides fiberoptic networks. It is more than 100 years since Alexander Graham Bell first demonstrated wireless optical communication, and free-space com muni cations have undergone enormous changes resulting from evolving optoelectronic technologies (see our Special Report starting on p. 164).
Other applications will benefit from R&D on wavelength-division multiplexing-vertical-cavity lasers for WDM are piquing interest in information-transfer applications, for example (see p. 235). Independent of the communications explosion, many other key applications continue to drive optoelectronics development. Ultrafast laser applications are gradually gaining prominence in the "real world" because the systems themselves are actually usable outside of a carefully controlled laboratory environment (see p. 137). New methods and laser sources have pushed back the limits of laser spectroscopy (see p. 177). And imaging and displays are benefiting from new sensors and lasers (see p. 197 and p. 263). But nowhere is the vast range of applied optoelectronics more evident than at this year`s Laser 99 in Munich, which is one of the world`s largest applications-oriented expositions devoted exclusively to laser technology and optoelectronics (see p. 253). Laser Focus World will be there!