Light beams with flat-topped profiles

A necessary condition for generating optical beams with a nearly uniform profile at a certain transverse plane is proposed. This proposal leads to the introduction of a set of light beams with flat-topped profiles. This set of beams can be expressed as a finite series of lowest-order Gaussian modes (TEM00) with different parameters. The main features of this set of beams are investigated and compared with those predicted by existing models of flattened Gaussian beams. (C) 2002 Optical Society of America.