The temporal pulse shaping was realized by using temporal-space transforming pulse-shaping system with the own-designed "Knife edge" apparatus, for the first time to our best knowledge, in a large energy laser facility with the output energy of 454.37J. A quasi-square laser pulse with the pulse width of 1.16ns, the rising time of 337ps, the falling time of 360ps, and the temporal filling factor of 81.2% was obtained. It is quite satisfied with the requirement of physical experiment. In addition, the further improvements of our system have been suggested in order to enhance the stability and the flexibility as well as the restoring ability of the temporal-space transforming process.
A diode pumped Nd:YLF regenerative amplifier is developed, which works at wavelength of 1053nm and repetition rates of 1Hz. It can produce laser pulses of 2mJ energy, 4ns width in the base transverse mode TEM00. Total gain of 1x107 is reached, and pulse-to-pulse energy fluctuation doesn't exceed ±4.7% Experimental setup and detailed results are presented.
A novel method is investigated for compensating deflection in a spatial-temporal transform pulse shaping system: using optical fiber instead of a second electrooptic deflector. By changing the width and shape of filter, pulse duration ranging from 740ps to 4.5ns is observed, and the mode quality of output beam is good. This novel method has relaxed requirements on electrooptic deflector and simplified the whole system.