Lossless Conversion of a Plane Laser Wave to a Plane Wave of Uniform Irradiance

Abstract

Interest has recently been shown in methods of converting the plane wave from a laser in the uniphase TEM_0,0 mode to a plane wave having (a) uniform irradiance over a required cross section, and (b) all the power of the original beam. Two methods are proposed for accomplishing these aims: one employs two plano-aspheric lenses; the other requires a pair of selectively aberrated lens systems. A computer program has been written which determines the aspherics, and one example is presented. The aberrations required of the second method are expressed algebraically in terms of known quantities. These aberrations could conceivably be designed into a system of spherical lenses, by use of one of the automatic lens design programs now extant.