Sughrue Mion, PLLC
Catadioptric projection objective
Catadioptric projection objective (1) for microlithography for imaging an object field (3) in an object plane (5) onto an image field (7) in an image plane (9), including a first partial objective (11) imaging the object field onto a first real intermediate image (13), a second partial objective (15) imaging the first intermediate image onto a second real intermediate image (17) and a third partial objective (19) imaging the second intermediate image onto the image field (7). The second partial objective (15) has exactly one concave mirror (21) and at least one lens (23). The minimum distance between an optically utilized region of the concave mirror (21) and an optically utilized region of a surface (25)—facing the concave mirror—of a lens (23) adjacent to the concave mirror is greater than 10 mm.
Carl Zeiss SMT GmbH
G G G
G02B G02B G03F
inventional inventional inventional
Toralf Ralf Alexander
Gruner Mueller Epple