Lasers do not typically have a uniform beam profile across the entire area of their output. Beam shapers are typically used to convert a gaussian beam intensity profile to a uniform "top hat" shape. These are often the most complex optics to design but MEMS Optical's gray scale lithography allows for the creation of extremely high performance beam shapers, often with uniformity within 2% with virtually no speckle present.
Beam shapers are usually diffractives and work best with a single mode beam but, if a multimode beam is used, a refractive beam integrator type can be made.
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