Frequency-resolved optical gating
= Frequency-resolved optical gating
= FROG
{disambiguate=optics}
{c}
{synonym}
Measure the spectrum of a nonlinear optical gate signal as its relative delay is varied. A retrieval algorithm seeks a complex pulse consistent with the resulting two-dimensional <intensity> record and the particular gate law. Different gate laws have different ambiguities and response limitations; a small fitting residual alone does not guarantee stable pulses or correct calibration.