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Documentary and Physical Standards for Surface Finish and Imperfections



Theodore V. Vorburger


Surface finish and imperfections are important properties of optical surfaces because they are caused by manufacturing limitations or defects and are linked to degradation of optical performance. Surface finish or surface roughness constitutes the numerous fine irregularities that cause scattering and stray light in optical systems. "Imperfections" is a general term to describe localized defects that mar the surface appearance and also cause stray light. We discuss here documentary standards for surface finish and both documentary and physical standards for surface imperfections. For surface finish, standards development organizations Include the American Society of Mechanical Engineers (ASME) Committee B46 on the Classification and Designation of Surface Qualities, the International Organization for Standardization (ISO) Technical Committee (TC) 213 on Dimensional and Geometrical Product Specifications and Verification, ISO TC172 on Optics and Optical Instruments, and the American Society for Testing and Materials (ASTM). Numerous standards have been produced by these organizations relating to surface finish specification, and surface profiling and scattering measurements. For surface imperfections in optics, dig and scratch standards were described in Military Specification MIL-O-13830A (1963) and related Drawing C7641866. Therefore this documentary standard Is directly linked to physical standards. Other standards developing organizations for imperfections include the ISO, The National Association of Photographic Manufacturers, Inc. and most recently the Optics and Electra Optics Standards Council (OEOSC). Standards for Imperfections written by these organizations include! ISO 10110-7, "Optics and Optical Instruments - Preparation of drawings for optical elements and systems -Part 7: Surface imperfection tolerances"; IS0 8785, "Geometrical Product Specification (GPS) - Surface imperfections - Terms, definitions and parameters"; and American National Standards Institute (ANSI) PH3.617-1980 "Definitions, Methods of Testing, and Specifications for Appearance Imperfections of Optical Elements and Assemblies."
Proceedings Title
Conference on Optics Manufacturing for Dual-Use
Conference Location
Redstone Arsenal, AL


dig, documentary standards, imperfections, inspection, measurement standards, scratch, surface


Vorburger, T. (2001), Documentary and Physical Standards for Surface Finish and Imperfections, Conference on Optics Manufacturing for Dual-Use, Redstone Arsenal, AL (Accessed April 17, 2024)
Created February 1, 2001, Updated February 19, 2017