Tunable lasers in optical networks

Tunable lasers have been the subject of considerable interest ever since the start of the wavelength division multiplexing (WDM) revolution. In this paper, we bring together views on tunable lasers from different types of companies in the value chain, from operators to laser manufacturers. The purpose of the paper is to give an overview of the state of the art in both deployment and development, as well as to try to predict trends over the coming years.