Abstract: A laser system includes a first laser (66) and a second laser (68) optically coupled to the first laser (66), characterized in that the first laser (66) is arranged to respond to pumping by producing a first laser output and retaining for a time period a net gain for second laser output radiation, and the second laser (68) is adapted to be pumped by the first laser output and to respond within the time period by producing a second laser output optically coupled to the first laser (66) to effect injection control thereof. The first laser (66) may be an excimer laser and the second laser (68) may be a dye laser. The lasers may be coupled by a common laser mirror (20).

Abstract: A dye laser capable of lasing at a plurality of wavelengths simultaneously, e.g. three, comprises a corresponding plurality of transparent containers 4, 5, 6 located between a partially-reflecting mirror 1 and a tiltably adjustable retroreflecting diffraction grating 2 with the containers transversely staggered. The staggered ends of the containers are irradiated by a shallow beam 9 from a pumping laser 7 and contain separate dye solutions whereof the emission spectra increase in wavelength from container to container starting from that container nearest the pumping laser. There are thus formed three parallel cavities which can lase simultaneously, tuned by the grating 2 operating in three different diffraction orders.