Laser technologies

Development of laser technology over the last decade or so has permitted spectroscopy to probe short-time events. Instead of having to resort to the study of reactants and products and their energetics and shuctures, one is now able to follow reactants as they travel toward products. Fast pulsed lasers provide snapshots of entire molecular processes [5] demanding similar capabilities of the theory. Thus, explicitly time-dependent methods become suitable theoretical tools. 

This is in contrast to lasers based on mby or neodymium in glass, which operate at much lower pulse-repetition rates. Nd YAG lasers are often operated as frequency-doubled devices so that the output is at 532 nm. These lasers are the most common type of soHd-state laser and have dominated sohd-state laser technology since the early 1970s. Nd YAG lasers having continuous output power up to 1800 W are available, but output powers of a few tens of watts are much more common. 

The examples given above represent only a few of the many demonstrated photochemical appHcations of lasers. To summarize the situation regarding laser photochemistry as of the early 1990s, it is an extremely versatile tool for research and diagnosis, providing information about reaction kinetics and the dynamics of chemical reactions. It remains difficult, however, to identify specific processes of practical economic importance in which lasers have been appHed in chemical processing. The widespread use of laser technology for chemical synthesis and the selective control of chemical reactions remains to be realized in the future. 

Although practical generation of energy by laser-assisted thermonuclear fusion remains well ia the future, the program has provided some of the most exacting requirements for laser technology and has led to advances ia laser equipment that have been adopted ia other areas. Thus the research and development associated with thermonuclear fusion work has helped to spur advances ia laser technology useful for many other appHcations. 

S. Lugomer, Laser Technology, Laser Driven Processes, Preatice-HaH, lac., Eaglewood Chffs, N.J., 1990. 

MPI is especially valuable for elemental analyses with typical useful yield of 10 . Because SALI is laser-based, expected improvements over the next few years, in particular for vacuum-ultraviolet laser technology, should have a significant impact. High repetition rate Nd—YAG systems with sufficient pulse energy are already available to 50 Hz, and probably can be extended to a few hundred Hz. 

Unlike these light sources, laser technology relies on a concept known as stimulated emission. Wlien an excited atom is stimulated by a photon, light is emitted at precisely the same wavelength and precisely in ph ase with the light wave that stimulated it. 

Laser printers, bar code readers, unmanned freeway tollbooths, laser pointers—none of these very common devices would be possible ivithout laser technology. This is just a minor sampling the list of laser applications goes on and on. 

It is not surprising that the reliability, portability and rapid energy release of pyrotechnic systems should have suggested their use in laser technology, both as light source for pumping and as the source for the inversion population. 

LASER TECHNOLOGIES FOR LASER GUIDED ADAPTIVE OPTICS... 

Laser Technologies forLaser Guided Adaptive Optics... 

Advances in laser technology now allow for solid-state lasers of high beam quality. These beams may be projected from a much smaller auxiliary telescope, which negates the need for optical switching and completely eliminates any main telescope fluorescence. Solid-state YAG lasers are the most common type of lasers commercially available. These lasers use a crystal as the lasing... 

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