摘要 |
<p>A method of wavelength locking and mode monitoring a tuneable laser (15) that includes two or more tuneable sections in which injected current can be varied, said sections including at least one reflector section and one phase section, wherein the laser (15) has been characterised with respect to suitable laser operation points that have been determined as different current combinations through the different laser sections, and wherein said laser operates in a predetermined, selected operation point. The invention is characterised by detecting the light emitted by the laser with respect to its wavelength with the aid of a wavelength selective filter; controlling the laser in an iterative process in which alternated currents through the reflector section (17) of said laser and, when applicable, its coupler section (19), and the current through the phase section (18) of said laser are adjusted; adjusting the currents through the reflector section and the coupler section so as to obtain a minimum with respect to the ratio between power rearwards (I3) and power forwards (I2); and adjusting the current through the phase section (18) of the laser so as to hold the wavelength constant, said wavelength being measured against a wavelength reference (32).</p> |