There are different kinds of refractive beam shapers of field mapping type used to transform the laser intensity distribution in order to get improvements or special effects in various laser technologies like welding, cladding, hardening, laser techniques in photovoltaics, etc. A right choice of a suitable beam shaper depends on physical specifications of a particular laser application. As a rule, when a final laser spot size is orders of magnitude greater than a laser wavelength, say of millimetre or centimetre scale, it is optimum to apply the beam shapers providing a collimated beam with flattop or another pre-determined output intensity profile. When a final spot size is comparable with the laser wavelength, say tens of microns in micromachining, it is advisable to apply the beam shapers intended to create the required intensity distribution in focal zone of a beam focused. Correspondingly, different kinds of refractive beam shapers, like πShaper or Focal-πShaper, should be applied. This paper will describe important features of intensity profile transformation in optical systems, principles of operation and design features of refractive field mapping beam shapers πShaper and Focal-πShaper. There will be presented examples of intensity transformation and effects on material processing in several industrial applications.
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