Inventors:
Arnaud Garnache - Montpillier cedex, FR
Daniele Romanini - Grenoble, FR
Frederic Stoeckel - Vaulnaveys le Haut, FR
Alexandre Katchanov - Sunnyvale CA
Guido Knippels - Sunnyvale CA
Barbara Paldus - Sunnyvale CA
Christopher Rella - Sunnyvale CA
Bruce Richman - Sunnyvale CA
Marc Levenson - Campbell CA
Robert Lodenkamper - Sunnyvale CA
Assignee:
BlueLeaf, Inc. - Sunnyvale CA
International Classification:
H01S 500
Abstract:
An optical fiber transmitter for emitting an information-carrying laser beam comprises an optically or electrically pumped single mode MQW (multi-quantum well) semiconductor amplifying mirror as a gain medium and a separate external reflector to form a cavity. The external cavity length defines a comb of optical modes, all or a subset of which correspond to channel wavelengths of an optical telecommunications system having plural optical channels. The semiconductor gain element has a homogeneously broadened gain region; a tuning arrangement tunes the laser from mode to mode across the gain region, thereby selecting each one of the plural optical channels. When the maximum gain bandwidth is less than mode-to-mode spacing defined by the cavity, the tuning arrangement includes a means of altering the temperature of the amplifying mirror, thereby translating the frequency of the gain peak from one mode to another. An optical modulator adds modulation to provide an information-carrying laser beam, and a coupler couples the information-carrying laser beam into an optical fiber of the optical telecommunications system. A calibration method based on detecting inter-mode optical transitions (mode hopping) is described.