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 and a wavelength-tunable spectral filter , - the light source 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 , 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 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 , spectrally filtered and wavelength-tunable as a function of the central wavelength of said spectral bandwidth of the spectral filter , - the light source 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 and a wavelength-tunable spectral filter , - the light source 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 , 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 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 , spectrally filtered and wavelength-tunable as a function of the central wavelength of said spectral bandwidth of the spectral filter , - the light source 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 . <EOS>