01523nas a2200157   4500008004100000245008300041210006900124520087000193100002001063700000501083700002201088700000501110700001401115700000501129856023101134       2007                        eng d00aUnited {States} {Patent}: 7196842 - {Attenuating} filter for ultraviolet light0 aUnited States Patent 7196842 Attenuating filter for ultraviolet 3 aAn attenuating filter provides a prescribed attenuation of the intensity of transmitted, short-wavelength, ultraviolet light, in particular, at wavelengths below 200 nm, that is governed by a predefinable spatial distribution of its spectral transmittance. The filter has a transparent substrate (3), e.g. fabricated from crystalline calcium fluoride. A filter coating (5) fabricated from a dielectric material that absorbs over a predefined wavelength range is applied to at least one surface (4) of the substrate. In the case of operating wavelengths of about 193 nm, the filter coating consists largely of tantalum pentoxide. Filters of the type, which may be inexpensively fabricated with high yields, are noted for their high abilities to withstand laser radiation and may be effectively antireflection coated employing simply designed antireflection coatings.1 aWeigl, Bernhard1 a1 aPaul, Hans-Jochen1 a1 aEva, Eric1 a  uhttp://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=16&f=G&l=50&co1=AND&d=PTXT&s1=%22Weigl%3B+Bernhard%22.INNM.&OS=IN/%22Weigl;+Bernhard%22&RS=IN/%22Weigl;+Bernhard%22