Comparative measurements of the duration of picosecond light pulses by direct and autocorrelation techniques

Light pulse durations in the range 20–60 ps were measured by the simultaneous use of a direct method (with an Agat SF-1 image-converter camera) and a correlation technique (noncollinear second harmonic generation in a single pulse). The diameter of the fundamental radiation beam was shown to influence the results of measuring the duration of light pulses by the correlation technique. Practical recommendations for correct measurements by this technique were developed.