| 摘要 |
<p>A method of evaluating a tuneable laser (15) and determining suitable laser operation points, wherein said laser includes two or more tuneable sections in which injected currents can be varied, of which sections at least one is a reflector section and one is a phase section. The invention is characterised by leading part of the light emitted by the laser (15) to an arrangement which includes a Fabry-Perot filter (32) and a first detector (33) and a second detector (34), said detectors being adapted to measure the power of the laser and to deliver a corresponding detector signal (I1, I2); arranging the detectors relative to the Fabry-Perot filter so that the detector signals (I1, I2) will contain information relating at least to the wavelength of the detected light; sweeping the currents through the tuning sections (17, 18, 19) such as to pass through different current combinations; measuring the ratio between the two detector signals (I1, I2) during said sweep, wherein the reflector current (17) is the inner sweep variable which is swept in one direction and then in an opposite direction back to its start value; and storing the control combination for said tuning currents when the ratio between the detector signals (I1, I2) lies within a predetermined range signifying that the emitted light lies within one of a number of wavelengths given by the Fabry-Perot filter (32) and said ratio lies within said predetermined range for a given reflector current in both sweep directions of said reflector current.</p> |
