Lightwave technology continues to advance toward transmission at higher bit rates over longer unrepeatered fiber spans. As the longest repeater spacings are attainable in the low-loss fiber window near wavelengths of 1.55 μm, the high chromatic fiber dispersion in that spectral band must be dealt with to allow transmission at high bit rates. A solution to the dispersion problem is provided by semiconductor lasers which can be modulated at multigigabit/sec rates with their spectrum controlled to operate at a single frequency. This field Is now a subject of active research in the U.S.A. and abroad.
© 1985 Optical Society of AmericaPDF Article