I thought beam expanders increased a laser beam's size. How can that help me to get a smaller spot?

A laser beam expander is designed to provide larger collimated beams in order to decrease spot sizes at large distances. Not only will the beam size be increased by a certain factor, but the beam divergence will also be decreased by the same factor. The result is a smaller spot size at long distances when compared to what the laser could produce by itself. For a more detailed explanation of the advantages of laser beam expanders, view Beam Expanders.