Refractive projection objective with a numerical aperture greater than 0.7, consisting of a first convexity, a second convexity, and a waist arranged between the two convexities. The first convexity has a maximum diameter denoted by D1, and the second convexity has a maximum diameter denoted by D2, and...http://www.google.de/patents/US7382540?utm_source=gb-gplus-sharePatent US7382540 - Refractive projection objective
