A system for generating ultra-short light pulses that are wavelength-tunable in a spectral domain comprised between the ultraviolet and the infrared, characterized in that said system comprises: - an injection module comprising a light source (9, 99) and a wavelength-tunable spectral filter, - the light source (9, 99) being adapted to generate short light pulses, of a duration comprised between several hundreds of picoseconds and a hundred of nanoseconds, said short light pulses extending over a spectral band of emission having a spectral width of several tens of nanometres to several hundreds of nanometres, - the spectral filter having at least one spectral bandwidth defined by a central wavelength and a spectral width comprised between 10 pm and 10 nm, and the central wavelength of said spectral bandwidth being tunable in a spectral range comprised in the spectral band of emission of the light source (9, 99), the spectral filter being adapted to spectrally filter and to temporally shape said short light pulses, so that the injection module generates ultra-short light pulses, of a duration of the order of a picosecond, spectrally filtered and wavelength-tunable as a function of the central wavelength of said spectral bandwidth; and - at least one optical amplifier (20, 21, 22, 30, 31, 32, 33, 34) arranged at the exit of the injection module, said at least one optical amplifier being adapted to receive said spectrally filtered and wavelength-tunable ultra-short light pulses and to generate by optical amplification ultra-short amplified pulses (120, 130), spectrally filtered and wavelength-tunable as a function of the central wavelength of said spectral bandwidth of the spectral filter, - the light source (9, 99) comprising a non-tinear amplifying loop mirror, the non-linear amplifying loop mirror comprising another optical amplifier arranged on the optical path of the non-linear loop mirror and the spectral filter being arranged on the optical path of the non-linear loop mirror. - an injection module comprising a light source (9, 99) and a wavelength-tunable spectral filter, - the light source (9, 99) being adapted to generate short light pulses, of a duration comprised between several hundreds of picoseconds and a hundred of nanoseconds, said short light pulses extending over a spectral band of emission having a spectral width of several tens of nanometres to several hundreds of nanometres, - the spectral filter having at least one spectral bandwidth defined by a central wavelength and a spectral width comprised between 10 pm and 10 nm, and the central wavelength of said spectral bandwidth being tunable in a spectral range comprised in the spectral band of emission of the light source (9, 99), the spectral filter being adapted to spectrally filter and to temporally shape said short light pulses, so that the injection module generates ultra-short light pulses, of a duration of the order of a picosecond, spectrally filtered and wavelength-tunable as a function of the central wavelength of said spectral bandwidth; and - at least one optical amplifier (20, 21, 22, 30, 31, 32, 33, 34) arranged at the exit of the injection module, said at least one optical amplifier being adapted to receive said spectrally filtered and wavelength-tunable ultra-short light pulses and to generate by optical amplification ultra-short amplified pulses (120, 130), spectrally filtered and wavelength-tunable as a function of the central wavelength of said spectral bandwidth of the spectral filter, - the light source (9, 99) comprising a non-tinear amplifying loop mirror, the non-linear amplifying loop mirror comprising another optical amplifier arranged on the optical path of the non-linear loop mirror and the spectral filter being arranged on the optical path of the non-linear loop mirror.