Patent ID: 7959310

Claim:
An optical arrangement, comprising: at least one reflective optical element that is arranged in a beam path of the optical arrangement and that reflects radiation in the soft X-ray- or EUV wavelength range, wherein the at least one reflective optical element has an optical surface, and the optical surface has an optical design, wherein the optical design comprises a reflective multilayer system further comprising a plurality of layers having a high refractive index alternately arranged with a plurality of layers having a low refractive index, wherein at least during operation of the optical arrangement the optical surface has an operating temperature of at least 30° C., wherein the optical design of the optical surface is configured to change with the temperature of the optical surface so that the optical arrangement exhibits predetermined optical characteristics at the operating temperature, and wherein the optical design of the optical surface is configured to change a thickness of at least one of: at least one layer of the plurality of layers of the high refractive index, or at least one layer of the plurality of layers of the low refractive index, in accordance with the temperature of the optical surface.