For this application, LASER COMPONENTS offers the Flexishaper beam shaping module from partners HOLO/OR. This module uses two identical diffractive optical elements placed on the same optical axis which, when rotated against one another can shape the beam propagated through them from 100% of the power in the central spot to ~80% of the power at the surrounding ring with almost no energy at the centre, with a continuous full range control of the power ratio in between these states.
The Flexishaper pair can be used with both single-mode and multi-mode lasers and can be adapted for large beams typically used with multi-kW lasers.