Grating objective and grating-beam splitter - has three gratings with axial ray and border ram of radiation beam interchanged at least three times

摘要

A grating objective comprises two diffraction gratings which are arranged one behind the other in the radiation path extending from the object side to the image side. The gratings are adapted and arranged so a beam ray which is an axial or a border ray for one grating is a border or axial ray, respectively for the other grating. A third grating is arranged in the radiation path formed by the two gratings so that the axial and border ray of a beam traversing the grating objective are intercharged at least three times. A beam shaper and grating objective with built-in beam shaper are also described.