Temporal double pulses, produced in femtosecond laser laboratories, sometimes positively, sometimes negatively affect the outcome of an experiment. In my research I have improved an already existing femtosecond laser pulse characterization technique, called SRSI to be able to reconstruct femtosecond double-pulse structures. In addition, I have investigated the impact of the double pulses on the spectral characteristics of high-order harmonics, generated in gaseous material, by changing the delay between the constituting pulses of the double-pulse structure
