METHOD OF TRANSFORMING FREQUENCY OF ULTRASHORT LASER PULSES AND DEVICE TO THIS END Russian patent published in 2009 - IPC H01S3/30 

FIELD: physics; optics.

SUBSTANCE: present invention relates to Raman lasers and can be used for transforming frequency of ultrashort laser pulses. In a combination-active medium, two laser chirped pulses with linear orthogonal polarisation, separated by a time interval which is less than the transverse relaxation time of the active medium. The energy of the first pulse should exceed the threshold value of stimulated Raman scattering energy, and the energy of the second (delayed) pulse should be less than the threshold value of stimulated Raman scattering energy. Using a polarisation changer, the combination component is separated from the delayed laser pulse and undergoes time compression. To implement the method, proposal is given of a device, containing a dispersive element, stimulated Raman scattering converter and a compressor, which also includes a λ/2 phase inverting plate, located behind the dispersive element. Behind the phase inverting plate, there is a polarisation changer, and behind it there are two mirrors, an optical delay line and a second polarisation changer. Between the stimulated Raman scattering converter and the compressor, there is a third polarisation changer.

EFFECT: wider spectral width of the combination component, shorter duration of the transformed pulse and more stable pulse form.

2 cl, 3 dwg