Abstract: A method of making a high-precision optical surface which may be used either as a Wolter-type segment in an X-ray mirror system or in a collector of a EUVL system or as a spherical, aspherical, or free form normal or grazing incidence mirror in an EUVL system is prepared by sagging a thin flat glass sheet onto a masterpiece, in particular a mandrel, made from a temperature-resistant material, such as an alumina based ceramic or a keatite glass ceramic. The glass sheet is polished to the desired surface roughness (14), is positioned to an upper surface of the masterpiece (16), and is heated (18) to effect sagging onto the upper surface of the masterpiece for generating a shaped body. Thereafter, the shaped body is cooled and removed from the masterpiece, is mounted within a holder (22), is inspected for deviations from the specification (24) preferably using interferometric measurements, and is corrected for defects (26), preferably using ion beam figuring.

Abstract: The invention is directed to an arrangement for measuring the absorption of a transparent specimen. The arrangement includes: a radiation source for supplying radiation; a radiation-integrating device defining a space enclosed by a wall having a reflective surface for multiply reflecting the radiation substantially uniformly throughout the space to diffusely illuminate the transparent specimen whereby diffused radiation passes through the transparent specimen; a photometric measuring unit for measuring the radiation passed through the specimen; and, a mount for mounting the specimen between the reflective surface and the measuring unit. The arrangement of the invention enables the absorption of transparent specimens to be measured which have unfavorable outer forms such as where the specimen contains no surfaces which are mutually parallel.