Abstract: The present invention discusses a modulation method and apparatus for modulating an extended-cavity laser (211). The method and apparatus (200-203) entails the use of each pulse in an input modulating pulse train as the trigger for the generation of a brief or “notch” pulse, i.e. a pulse that briefly diminishes the normal drive current. Each “notch” pulse is used to drive the semiconduct (211) embedded in an extended cavity with a current that flows opposite to its normal drive current. This serves to diminish the inverted charge-carrier population essential to lasing action, so the laser output falls sharply in a form of amplitude modulation. The invention also discloses a simple, miniaturized means (372, 352, 312) of micropositioning, based on the differential rotation of nested conical plugs, that can serve to couple the semiconductor laser to the cavity.

Abstract: A multi-line continuous wideband tunable laser (1) utilizes a symmetric or asymmetric grating (5) and a plurality of optical fibers (3), each of which forms a part of a respective laser cavity optical axis. By simultaneously altering both the periodicity of the intersections of the grating (5) with the plurality of optical axes established by the plurality of optical fibers (3) and the effective cavity length of each laser (1), a single-line spectral output is achieved at any desired point in the operating band.

Abstract: A single-line continuous wideband tunable laser utilizes a symmetric or asymmetric grating. By simultaneously altering both the periodicity of the intersections of the grating with the optical axis and the laser effective cavity length, a single-line spectral output is achieved at any desired point in the laser's operating band.