You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither SPIE nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the SPIE website.
15 November 2019Creating sub angstrom surfaces on planar and spherical substrates
Sub-Angstrom surfaces are frequently specified by customers requiring increased optical and energy efficiency, with most stringent requirements from applications in the UV and from certain high power laser systems. Much research has been performed to understand related surface dynamics, with considerable amounts of information published on precision finishing of optical glass. Many suppliers of low roughness surfaces rely on finishing methods that create subsurface damage through the aggressive removal of material. While the magnitude of this damage can be minimized through the use of progressively finer abrasives, detectable levels of latent structure are still evident. However, finishing processes that merely wipe clean the Beilby layer without disturbing the substrate produce nearly perfect surfaces with little to no subsurface damage. This has been the focus of development efforts at Edmund Optics. By careful management of process variables, extremely smooth surfaces lacking subsurface damage have been demonstrated in fused silica and N-BK7 materials. Applications for optics having these characteristics are found in automotive, defense, medical, and industrial domains. This paper discusses results achieved for producing sub-Angstrom surfaces on fused silica and N-BK7 glass. Surfaces with measured roughness of 0.5Å have consistently been demonstrated on fused silica, with results of around 0.8Å shown for N-BK7. Types of processes useful for achieving these results will be discussed, along with basic metrology methods for producing reliable sub-Angstrom measurements.
The alert did not successfully save. Please try again later.
J. Nelson, S. Iles, "Creating sub angstrom surfaces on planar and spherical substrates," Proc. SPIE 11175, Optifab 2019, 1117505 (15 November 2019); https://doi.org/10.1117/12.2536689