System for generating short optical pulses of a duration shorter than the period of the optical carrier using the principle of parametric amplification

摘要

A generator of short optical pulses includes:a generator of optical pulses with a wavelength equal to λ/2 and a spectral width less than λ/3;a generator of optical pulses of a duration less than 10 picoseconds at a wavelength λ/3;a device for recombining the pulses from the generators;a parametric amplification device receiving the output of the recombination device as input;a filter extracting, from the output of the amplification device, a band centered about a wavelength λ;a second harmonic generator receiving the output of the filter and generating a band centered over a wavelength λ/2; anda programmable device making it possible to temporally adjust the pulses corresponding to the bands, in order to allow for the generation of a pulse with a wavelength equal to λ/3 and of a duration less than the period of the optical cycle.