A top hat laser beam is a laser beam whose intensity profile is flat and uniform, with sharp edges where the energy drops rapidly to zero.
Beam Expander is critical for Beam Shaping – Precision Laser Scanning
Diffractive Optical Elements
Stable Top or Top Hat, Laser Components Germany GmbH, Story - PresseBox
Top Hat Beam Shaper, Round Top Hat Spot
Flat-Field Super-Resolution Localization Microscopy with a Low-Cost Refractive Beam-Shaping Element
Energies, Free Full-Text
Gaussian beam - Wikipedia
Confocal microscope imaging improved with beam shaping – Precision Laser Scanning
Enhancing laser thin-film ablation
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What is a Top Hat Beam Profile?
Understand the difference between Tophat beam and Gaussian beam in one article