Beam control apparatus for an illumination beam and metrology system comprising an optical system containing such a beam control apparatus

摘要

A beam control apparatus for an illumination beam includes an imaging illumination optical unit assembly for imaging an intermediate focus of the illumination beam onto an object field to be illuminated. A control component that influences a beam path of the illumination beam is displaceable in at least one degree of freedom by at least one displacement actuator. A position sensor device of the beam control apparatus detects a position of the intermediate focus. A control device of the beam control apparatus is signal-connected to the position sensor device and the displacement actuator. From an intermediate focus position signal received from the position sensor device, the control device calculates control signals for the displacement actuator and forwards the latter to the displacement actuator for controlling the position of the intermediate focus. This results in a beam control apparatus which makes well-controllable illumination possible together with a simple construction.

主权项

1. A beam control apparatus for an illumination beam comprising
at least one control component which influences a beam path of the illumination beam in the illumination beam path upstream of an aerial image of an object illuminated by the illumination beam, said component being displaceable in a controlled manner in at least one degree of freedom by at least one displacement actuator, the at least one control component being located in the illumination beam path upstream of the object, a position sensor device for detecting a position of the aerial image of the object, and a control device that is signal-connected to the position sensor device and the displacement actuator and calculates control signals for the displacement actuator from an aerial image position signal received from the position sensor device and forwards said control signals to the displacement actuator for controlling the position of the aerial image of the object, wherein the beam path of the illumination beam is directly influenced by the control component, wherein the control component is at least one of a component which is mechanically directly connected to a beam section or a component which is mechanically directly connected to at least one surface that guides the illumination beam path.