Patent ID: 6826206
Filing Date: 2004-11-30
Classification: H01S

Abstract:
A method of evaluating a tunable laser and determining suitable laser operation points, the laser including two or more tuning sections in which injected tuning currents can be varied, the two or more tuning sections comprising at least a phase section and a reflector section, the method comprising:leading part of the output light emitted by the laser to a first detector that produces a first detector signal indicative of output power of the laser and to a second detector via a Fabry Perot filter, the second detector producing a second detector signal at least partly indicative of the wavelength of the light emitted by the laser; sweeping the tuning currents to pass through different current combinations, including sweeping a current through the reflector section in one direction and then in a second direction; determining ratios of the first and second detector signals corresponding to the different current combinations; and storing a control combination for the tuning currents, corresponding to an operation point, when the ratio of the first and second detector signals lies within a predetermined range signifying that the emitted light lies within one of a number of wavelengths given by the Fabry-Perot filter and the ratio lies within the predetermined range when the reflector current is swept in both the first and second directions.