Collinear Autocorrelation Measurement of Ultrashort Laser Pulse Based on Michelson Interferometer

The collinear autocorrclation measurement method is adopted based on the principle of Michelson interferometer, in which the intensity autocorrclation and the two-dimensional electric field autocorrclation arc simultaneously measured. A Gaussian function is used to fit the intensity autocorrclation data and the full width at half maximum of the measured laser pulse in time domain is about 96.2 fs. From the interference fringe distribution of two-dimensional electric field autocorrclation obtained by the CMOS imaging sensor, the tilt information of pulsed light spot wavefront phase can be obtained. Moreover, the Fourier series analysis tool is adopted to fit the interference fringes shifting with time delay. Within the restriction of delay stage accuracy, a weak component at 1090 nm is disclosed in the pulsed laser power spectrum.