An apparatus and method for modifying the spread of a laser beam. The
apparatus comprises a laser source operable to generate a laser beam
having a flux that exceeds a predetermined value and an optical train
operable to modify the beam such that the flux of the beam through a
predetermined aperture does not exceed the predetermined value. The
optical train may include a focusing lens, a diffractive focusing vortex
lens, a beam splitting device, or a diffraction grating.