Research Of Laser-transmission Technique Of High-energy Ultrashort Pulse-laser Systems

There had been large development of technique of high-energy ultrashort pulse-laser systems in the thirty years after the appearance of the conception fs . Especially the appearance and development of the chirped-pulse amplification and the kerr-lens mode locking had laid a good foundation for the flourish of the ultrashort pulse laser, in the last decade. As we all know, then, the ultrashort progress did spade works for the research of the interaction between the light and matter, especially, at the extreme physical condition because of the characteristics of ultrashort pulse-laser. So sets of high-energy ultrashort pulse-laser systems had been upbuilt in several countries and we need to develop our technique of ultrashort pulse-laser to upbuild high-energy ultrashort pulse-laser system too. At the instruction of the director, author had studied the unit technique of the high power laser system at the theory and experiment respects in order to develop our technique of ultrashort pulse-laser to upbuild high-energy ultrashort pulse-laser system . The main work and achievment as following.First of all, we review the development of ultrashort pulse-laser technique ,and key techniques to upbuild high-energy ultrashort pulse-laser system and estimate of the techniques are introdused.In the body of the paper, author's main work and results is introdused.1. Study and d esign o f s ptial filter i n h igh p ower femtosecond 1 aser sy stem. Owing to the PTD effect in the lenses of spatial filter, large temporal front distortion of femtosecond pulses occurs in the spatial filter . In order to design a spatial filter which is applicable to high power femtosecond lasersystem, it is discussed that achromatic doublet or separated doublet replacethe single lenses in spatial filter to eliminate or reduce the PTD effect.2. Serrated-aperture apodizers for high-energy ultrashort pulse-laser systems The transmission features of the ultra-short pulsed-laser passing through the serrated aperture and spatial filter is studied in allusion to clean and uniform intensity distribution in the high-energy ultrashort pulse-laser system. The diffracti6n modulation of ultrashort pulsed-laser is less than CW laser, so we can use only serrated aperture to get uniform near-field uniform intensity distribution.3. Alignment and adjustment of the streacher and compressor in high-energy ultrashort pulse-laser system.Lastly, we introduced the basic configuration, design and research results of the high-energy ultrashort pulse-laser system. Effect of some key parts of an apparatus is discussed .