Patent ID: 8446665

Claim:
A catadioptric projection objective for microlithography for imaging an object field in an object plane onto an image field in an image plane with radiation, comprising: a first partial objective imaging the object field onto a first real intermediate image, a second partial objective imaging the first intermediate image onto a second real intermediate image, wherein the second partial objective is a catadioptric objective having exactly one concave mirror and having at least one lens, a third partial objective imaging the second intermediate image onto the image field, and a first folding mirror deflecting the radiation from the object plane toward the concave mirror and a second folding mirror deflecting the radiation from the concave mirror toward the image plane, wherein at least one surface of the lens of the second partial objective has an antireflection coating having a reflectivity of less than 0.2% for an operating wavelength of between 150 nm and 250 nm and for an angle-of-incidence range of between 0° and 30°.