Method and apparatus for modifying the spread of a laser beam

摘要

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 two-dimensional diffraction grating.