Light sources and light source systems for non-medical use, in particular lasers, fiber lasers, solid state lasers, laser diodes, tunable diode lasers, narrow linewidth lasers, broadband light sources, supercontinuum light sources, and pulsed lasers, in particular lasers providing femtosecond-, pictosecond- or nanosecond pulses; components for modifying the properties of a light beam, in particular optical filters and optical frequency conversion devices; optical amplifiers; optical fibers an...