Research On The Femtosecond Pulse Retrieval Technology Of GRENOUILLE

Ultrashort pulse has many characteristics, such as high peak power and narrowpulse width, etc. In physics, biology, medicine, chemical reaction control, opticalcommunication, high-density storage and record, fine processing and other industries,ultrashort pulse was widely used. With the ceaseless development of ultrashort pulsetechnology, the pulse width becomes more and more short. The traditional measuringmethods are unable to realize measurement of ultrashort pulses. But this dissertationbased on the method of Grating-Eliminated No-nonsense Observation of UltrafastIncident Laser Light E-fields(GRENOUILLE), can accurately measure the pulsewidth, waveform and phase information of femtosecond pulses.The work in this dissertation mainly includes the following aspects:1. The pulse measurement technology of ultrashort pulses has been simplyreviewed, focusing on expounding the development of ultrashort pulse lasertechnology and pulse measurement technology. The theory of second harmonicgeneration of femtosecond pulses has been introduced in detail, and the method ofcollinear and noncollinear schemes of Frequ ency-resolved optical gating is analyzed.At the same time, the collinear scheme of frequency doubling signal retrieval isstudied. The measuring principle and technical characteristics of GRENOUILLE areintroduced and analyzed, together with the PCGPA algorithm of retrieval technology.2. An experimental system was set up with suitable optical elements. Ultrashortpulses generated by Ti-doped titanium sapphire femtosecond laser with800nm weremeasured. Some FROG traces were taken by the CCD camera. The algorithm ofPCGPA was realized by MATLAB through compiling the program of ultrashort pulseretrieval.3. Through the MATLAB inversion program, the retrieval process of ultrashortpulses were simulated; Using the frequency doubling spectrogram in experiment, theretrieval of the ultrashort pulse waveforms was completed. Measurement shows: the results are consistent with the pulse parameters, while the noise of the retrieval pulseis mainly from the refraction by the slit. Finally, the optimal iteration parameter andimage distance are obtained by an analysis.