An optical assembly, EUV lithography apparatus and method for configuring an optical assembly

The invention relates to an optical arrangement, in particular a projection objective for microlithography, comprising: at least one optical element (21) comprising an optical surface (31a) and a substrate (32), wherein the substrate (32) is formed from a material whose temperature-dependent thermal expansion coefficient at a at a reference temperature T d wherein the zero-crossing The invention also relates to an EUV lithography apparatus with such an optical arrangement in the form of a projection lens, and an associated method for configuring the optical arrangement.