Abstract

The use of N-frequency tunable distributed Bragg reflector (DBR) lasers has been suggested for WDM switching and routing networks [1-2]. Such networks will tune lasers to different optical frequencies, to enhance the transmission capacity through optical fibers, and also to direct optical signals to different destinations. The networks presently under consideration will have 10-20 frequency channels, with 50-100 GHz (4.05-8.1 Å) channel spacing in the 1.54-1.56 micron wavelength window. If DBR lasers are to be used, it is critically important to establish that the tuning mode spacing of the lasers is constant, and can be reproduced with a high degree of accuracy, so that a constant channel allocations can be maintained throughout the system. For each laser being used, a tuning curve must be established. At present, it can be measured by means of a wavemeter or an optical spectrum analyzer. The tuning curve shows the optical frequency of the laser vs. the current applied to the tuning (grating) section, and determines the different currents that should be applied to address the different frequencies.

© 1994 Optical Society of America