Flat-top beams are a light beam with a relatively flat intensity profile -- in contrast to Gaussian beams, for example. They often have a super-Gaussian shape.
A 100-PW compressor based on single-pass single-grating pair, High Power Laser Science and Engineering
Flat-Top Converter Top Hat – Workshop of Photonics
PoloRevBucketSP S/M BEAMS
Tailoring light with a digital micromirror device - Ren - 2015 - Annalen der Physik - Wiley Online Library
Flattop and square beam profiles as a function of the shape and size of
PA-15 de Mata Et Al, PDF, Laser
How to design a Gaussian to Top Hat beam shaper – Knowledgebase
How to design a Gaussian to Top Hat beam shaper – Knowledgebase
Top-Hat / Flat-Top Beam Shaper application notes - Holo Or
Laser Beam Shaping Overview
Flat-top laser beams: Their uses and benefits
Process Overview DEGRADATION AND SURFACE ENGINEERING
Creating a Top-hat Laser Beam Focus
flat-top beams, explained by RP; top-hat beam, supergaussian, intensity profile, beam shaper