Theory and techniques for laser beam shaping

Many basic experiments as well as industrial and military applications require laser beams that have specified shape or irradiance profile. A common requirement is a laser profile that is uniform over some cross-section. Such applications include laser/material processing, laser material interaction studies, fiber injection systems, optical data/image processing, lithography, medical applications, optical metrology, and military systems. Laser beam shaping techniques can be divided in to three areas: apertured beams, field mappers, and multi-aperture beam integrators. An uncertainty relation exists for laser beam shaping that puts constraints on system design. In this paper we review the basics of laser beam shaping and discuss the limitations of the three major techniques.