Laser processing of workpieces

A method for processing a transparent workpiece includes generating a beam of radiation and forming a defect in or on an object. The beam is a quasi-non-diffracting beam and has a focal volume. Forming the defect includes directing the beam onto the object and positioning the focal volume partially or fully within the object. Generating the beam includes partially blocking the beam upstream of the focal volume to adjust an axial symmetry of the freeform energy distribution with respect to an optical axis of the beam using an adjustable blocking element and/or spatially modulating a phase of the beam upstream of the focal volume to adjust a geometry of the freeform energy distribution using a phase mask. The freeform energy distribution has energy sufficient to induce multi-photon absorption in a region of the object that is co-located with the focal volume. The induced multi-photon absorption produces the defect.