Patent ID: 7548387
Filing Date: 2009-06-16
Classification: F16C,G02B,G03F

Abstract:
1. A projection objective for microlithography, having at least one optical element which is provided with an outer frame, an inner ring in which the optical element is mounted, and a manipulator instrument having at least one actuator, wherein contactless linkage of the inner ring to the outer frame is provided in at least one degree of freedom by means of a support arranged between the inner ring and the outer frame, the manipulator instrument having at least one actuator, the setting forces and/or bearing forces of which act contactlessly on the inner ring, for mounting and/or positioning and/or manipulating the inner ring relative to the outer frame to reduce parasitic effects, said at least one degree of freedom including at least one degree of freedom other than rotation about an optical axis of the projection objective, the support comprising a fluid bearing, the fluid bearing comprising a gas bearing, the gas bearing having at least one gas feed line and at least one gas discharge line.