A microlithographic projection exposure apparatus includes a primary illumination system producing projection light, a projection objective and a correction optical system. The correction optical system includes a secondary illumination system, which produces an intensity distribution of correction light in a reference surface, and a correction element which includes a heating material and is arranged in a plane that is at least substantially optically conjugate to the reference surface such that the correction light and the projection light pass through at least one lens contained in the projection objective before they impinge on the correction element. All lenses through which both the correction light and the projection light pass are made of a lens material which has a lower coefficient of absorption for the correction light than the heating material contained in the correction element.