Three-section semiconducting DFB laser with increased wavelength tuning range

摘要

A decisive disadvantage of all previously disclosed three-section DFB semiconductor lasers is their small wavelength tuning ranges, compared with other semiconductor lasers. The invention is based on the object of developing a laser which combines the advantages of three-section DFB semiconductor lasers with an increased wavelength tuning range without mode shifts. The object is achieved according to the invention by means of a three-section DFB semiconductor laser, which has different section lengths, in which the laser position of the phase shift is arranged outside the centre of the semiconductor laser and which is operated with at least one or two different currents. The laser according to the invention makes possible a high light yield even at a high coupling coefficient. IMAGE