title: A deterministic optical figure correction technique that preserves precision-polished surface quality.
abstract: A deterministic surface correction technique has been used to improve the surface figure of two fused silica optical flats over a diameter of 60 mm with no measurable degradation in their surface quality at spatial frequencies of <or= 750 mm(-1). The surface corrections were achieved by selective ion beam sputtering (IBS) deposition of an index-matched dielectric layer through a multi-aperture mask. Two flats were corrected, one finished on a pitch lap, the other on a Teflon lap to give two distinctly different surface roughness characteristics. The microroughnesses measured on a TOPO-WYKO profilometer were 3.0 A and 7.2 A respectively. Both optics were improved to better than lambda /100 peak-to-valley and in each case the surface correction process preserved or potentially improved the microroughness of the optic.
authors.affiliation: CSIRO Materials Science and Engineering, Lindfield, NSW 2070, Australia. john.arkwright@csiro.au
authors.forename: John
authors.initials: J
authors.lastname: Arkwright
authors.forename: Jan
authors.initials: J
authors.lastname: Burke
authors.forename: Mark
authors.initials: M
authors.lastname: Gross
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007909:Lenses; D008962:Models, Theoretical; D011786:Quality Control; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D012822:Silicon Dioxide