Abstract
The pulse width of a ultrafast optical pulse is usually less than a few picoseconds and the ultrafast optical pulse can not be directly resolved in the time domain by the existing photodetectors. The method of Dual-quadrature spectral shearing interferometry (DQ-SSI) takes the three sum-frequency generation spectra of the pulse train with the probe electric field to recover the spectral phase of the pulse. The probe electric field consists of a pair of single-frequency tones. In the thesis, the mathematical model of the probe electric field with random phase noise has been built up. The sum-frequency generation spectrum in the presence of random phase noise has been theoretically derived. And the key parameters of the random phase noise which affect the reconstruction of spectral phase have been found out. The dependence between the error of the reconstruction of spectral phase and these key parameters has been discussed.