A system for generating polychromatic light, which includes: an optical pumping device suitable for continuously or quasi-continuously emitting a monochromatic or quasi-monochromatic radiation according to a pumping wavelength; a device for guiding light arranged such as to emit polychromatic radiation continuously or quasi continuously, at the output thereof, and a device for coupling between the pumping and coupling device. In the system, the guiding device, includes a microstructured optical fiber in which the core is at least partially doped with a material having a high intrinsic non-linear response, and the geometry of the optical fiber and the doping rate of the core thereof are predetermined such as to adapt the zero dispersion length of the optical fiber to the pumping wavelength.