Variable stopper for optic element e.g. mirror used in projection exposure system, has stopper element that is provided to limit movement path of optical element

摘要

The stopper has stopper element (4) that is provided to limit the movement path of the optical element (1). The distance of component from the stop surface (6) is maintained in predefined region by adjusting stopper element. The lever arm (7) is connected with stopper element. The lever arm is rotated in rotational axis according to the displacement of stopper element. The actuators (10,11) are connected with optical element. Independent claims are included for the following: (1) positioning system for accurate positioning of component; and (2) method for exact positioning of component.