A faceted reflector (32, 32″) for receiving an incident radiation beam (2) and directing a reflected radiation beam at a target. The faceted reflector comprises a plurality of facets, each of the plurality of facets comprising a reflective surface. The reflective surfaces of each of a first subset of the plurality of facets define respective parts of a first continuous surface and are arranged to reflect respective first portions of the incident radiation beam in a first direction to provide a first portion of the reflected radiation beam. The reflective surfaces of each of a second subset of the plurality of facets define respective parts of a second continuous surface and are arranged to reflect respective second portions of the incident radiation beam in a second direction to provide a second portion of the reflected radiation beam.