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Beam Shaping of the spatial (transverse) profile of laser beams is highly desirable by building optical systems of high-power
lasers as well in various applications with these lasers. Pumping of the crystals of Ti:Sapphire lasers by the laser
radiation with uniform (flattop) intensity profile improves performance of these ultrashort pulse high-power lasers in
terms of achievable efficiency, peak-power and stability, output beam profile. Specifications of the solid-state lasers built
according to MOPA configuration can be also improved when radiation of the master oscillator is homogenized and then
is amplified by the power amplifier. Features of building these high power lasers require that a beam shaping solution
should be capable to work with single mode and multimode beams, provide flattop and super-Gauss intensity
distributions, the consistency and divergence of a beam after the intensity re-distribution should be conserved and low
absorption provided. These specific conditions are perfectly fulfilled by the refractive field mapping beam shapers due to
their unique features: almost lossless intensity profile transformation, low output divergence, high transmittance and
flatness of output beam profile, extended depth of field, adaptability to real intensity profiles of TEM00 and multimode
laser sources. Combining of the refractive field mapping beam shapers with other optical components, like beam-expanders,
relay imaging lenses, anamorphic optics makes it possible to generate the laser spots of necessary shape, size
and intensity distribution. There are plenty of applications of high-power lasers where beam shaping bring benefits:
irradiating photocathode of Free Electron Lasers (FEL), material ablation, micromachining, annealing in display making
techniques, cladding, heat treating and others.
This paper will describe some design basics of refractive beam shapers of the field mapping type, with emphasis on the
features important for building and applications of high-power laser sources. There will be presented results of applying
the refractive beam shapers in real installations.
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