Sub-20 fs pulses shaped directly in the UV by an acousto-optic programmable dispersive filter.

Direct pulse shaping in the UV was used to compress and structure pulses throughout the range of 250 - 400 nm. Broadband pulses generated by SHG of a NOPA were used as input to an acousto-optic programmable dispersive filter. As this shaper creates lateral dispersion, aspects of Gaussian and geometric optics had to be considered for the design of the beam path. Special care was taken to produce a homogeneous input beam. We show nearly Fourier-limited pulses as short as 16.8 fs at 320 nm and 19.5 fs at 260 nm. Full control over amplitude and phase is demonstrated by generating arbitrary shapes like square pulses and complex pulse sequences. The subpulses were manipulated individually in intensity, temporal delay, chirp, relative phase and central wavelength.