A system for generating pump illumination for laser sustained plasma (LSP) is disclosed. In embodiments, the system includes an illumination source and a beam shaper. The illumination source can be configured to output illumination having a first pupil power distribution. In embodiments, the beam shaper is configured to receive the illumination having the first pupil power distribution from the illumination source and is further configured to output pump illumination having a second pupil power distribution that is different from the first pupil power distribution.