Magnifying imaging optical unit and metrology system including same

摘要

An imaging optical unit includes at least four mirrors to image an object field in an object plane into an image field in an image plane. The ratio of the structural length of the imaging optical unit to the imaging scale of the imaging optical unit is less than 4.9 mm. The imaging optical unit provides improved handling properties, such as, for example, when used in a metrology system.

主权项

1. An imaging optical unit having an object field in an object plane and an image field in an image plane, the imaging optical unit comprising:
at least four mirrors configured to image the object field along a beam path into the image field, wherein a ratio of a structural length of the imaging optical unit to an imaging scale of the imagining optical unit is less than 4.9 mm, and the imaging optical unit has an intermediate image plane between the object field and the image field.