Lithographic apparatus, method of setting up a lithographic apparatus and device manufacturing method

A lithographic apparatus comprising:

• an optical component connected to a frame;
• and
• a radiation output configured to irradiate a surface of the frame so as to at least partially melt a portion at and near the surface of the frame so that the portion contracts as it cools, thereby adjusting the position and/or orientation of the optical component.

A device manufacturing method comprising:

• providing a plurality of radiation beams;
• and
• projecting the plurality of radiation beams onto a substrate through a lens group array, wherein the plurality of radiation beams are projected onto the substrate via a focus adjuster comprising an optical element having substantially zero optical power in an optical path of a corresponding lens group of the lens group array.

A method of adjusting a position and/or orientation of an optical component, connected to a frame, of a lithographic apparatus, the method comprising:

• irradiating a surface of the frame so as to at least partially melt a portion at and near the surface of the frame so that the portion contracts as it cools, thereby adjusting the position and/or orientation of the optical component.