US Patent 7738176 Lenslet array for beam homogenization

Apparatus for homogenizing a laser beam includes a lenslet array. In some embodiments, the lenslets have a negative power. The lenslet array may include from 16 to 36 effective lenslets in some embodiments, or any other suitable number in alternative embodiments. Some embodiments additionally include a re-focusing lens for directing the beamlets onto a target so that the beamlets overlap and the energy distribution is homogenized. In an alternative embodiment, the lenslet array and re-focusing lens are combined in one optic.