A single-shot third-order autocorrelator for pulse contrast and pulse shape measurements

We present the design of a single-shot third-order autocorrelator that can be used to measure optical pulse lengths of ultrashort pulses within a fixe d time window on a single-shot basis. It has a number of advantages over tr aditional second-order autocorrelation devices, namely a more direct and ac curate measurement of pulse shape, the ability to differentiate temporal ac tivity ahead and behind the pulse, and an increased dynamic range. The desi gn is linear and is, in principle, no more difficult to construct and opera te than a second-order autocorrelator.