Abstract: A device for reducing time distortion generated in light pulses by an optical frequency converter including at least one nonlinear optical component (4) having a nonlinear optical susceptibility ? of about 2 or 3, the converter being capable of receiving at least one incident pulse light beam (2), the incident light pulses having a duration ?t0, an optical frequency ?0±??0 and an intensity I0(t), and of generating, by frequency conversion, at least one output pulse beam (3), the output light pulses having a duration ?t1, an optical frequency ?1±??1 different from ?0±??0, and an intensity I1(t). The time distortion-reducing device includes a pre-compensation linear time filter (5) provided on the path of the incident beam (2), and capable of reducing the intensity time distortions generated in the frequency-converted output light pulses to at least one pre-compensation intensity Icomp.

Abstract: A method for spreading a spectrum of a narrowband signal, e.g. a monochromatic optical signal or a radiofrequency carrier. The method uses a phase modulation using a modulation signal that includes a plurality of sinusoidal components, the plurality including a component at a fundamental frequency and at least one component at a frequency that is a harmonic of the fundamental frequency, the sinusoidal components being synchronous and affected with phases respectively equal to consecutive multiples of ?/2.

Abstract: A device for reducing time distortion generated in light pulses by an optical frequency converter including at least one nonlinear optical component (4) having a nonlinear optical susceptibility ? of about 2 or 3, the converter being capable of receiving at least one incident pulse light beam (2), the incident light pulses having a duration ?t0, an optical frequency ?0±??0 and an intensity I0(t), and of generating, by frequency conversion, at least one output pulse beam (3), the output light pulses having a duration ?t1, an optical frequency ?1±??1 different from ?0±??0, and an intensity I1(t). The time distortion-reducing device includes a pre-compensation linear time filter (5) provided on the path of the incident beam (2), and capable of reducing the intensity time distortions generated in the frequency-converted output light pulses to at least one pre-compensation intensity Icomp.

Abstract: A method for spreading a spectrum of a narrowband signal, e.g. a monochromatic optical signal or a radiofrequency carrier. The method uses a phase modulation using a modulation signal that includes a plurality of sinusoidal components, the plurality including a component at a fundamental frequency and at least one component at a frequency that is a harmonic of the fundamental frequency, the sinusoidal components being synchronous and affected with phases respectively equal to consecutive multiples of ?/2.