A lithographic apparatus is disclosed. The apparatus includes an illumination system to provide a beam of radiation, and a support structure for supporting a patterning device. The patterning device serves to impart the beam with a pattern in its cross-section. The apparatus also includes a gas flushing device for flushing a substantially laminar flow of gas across the beam of radiation and/or along a surface of an optical component. The gas flushing device includes a single gas outlet that has an inner rim at a downstream end of the gas outlet. The inner rim defines a total gas outlet area. The gas outlet is provided with a laminator that has an effective area out of which, in use, the substantially laminar flow of gas flows. The laminator effective area includes material that has laminator openings and is at least as large as the total gas outlet area.