An optical element, especially a normal-incidence collector mirror, for radiation in the EUV and/or soft X-ray region of wavelengths is described. The element has a substrate, a multilayer coating with an optically active region, and a capacitor, having a first and a second capacitor electrode. At least one layer of the multilayer coating serves as the first capacitor electrode. At least one dielectric layer is provided between the two capacitor electrodes. Also described is an optical system with at least one optical element, having a first electrode arranged in the vicinity of the optical element.