Patent ID: 7684125

Claim:
An optical imaging device, in particular an objective for carrying out semiconductor microlithography at an extreme ultra-violet wavelength, said device comprising: a plurality of optical elements disposed in a beam path for a beam of extreme ultra-violet light; a plurality of diaphragms each of which has a respective diaphragm opening of a fixed geometry, said fixed geometry of said diaphragm openings being different in different respective ones of said diaphragms and, a diaphragm device for storing said diaphragms in a diaphragm store and selectively exchanging diaphragms between said diaphragm store and an operating position, said diaphragm openings of said diaphragms present in said diaphragm store being located out of the beam path, the said diaphragm opening of a said diaphragm present in said operating position being located in the beam path, whereby the objective can be selectively stopped down according to the said fixed geometry of the said diaphragm opening of any one of said diaphragms from said diaphragm store which is selectively introduced into said operating position.