Beam homogenizers for use with high-power lasers are available from Suss MicroOptics SA. The company offers imaging and nonimaging types, both of which use either cross-cylindrical or square microlens arrays to divide the incident beam into beamlets, which are then passed through a spherical Fresnel lens to be overlapped at the homogenization focal plane. Parallel bundles of rays converge in the homogenization plane where 2-D Fourier transformation takes place. The intensity pattern in the plane is related to the spatial frequency spectra generated by the microlens array entering the Fourier lens. The homogenizers work with lasers from 193 to 1064 nm and with beam diameters from 2 to 160 mm.