Cubic Boron Nitride Coatings for High-Reflectance Telescope Optics

摘要

The objective of the project was to deposit thin ion-beam-deposited boron nitride (i-BN) coatings on silvered and aluminized substrates, to investigate the potential of these coatings to provide environmental protection for front-surface telescope mirrors, and to evaluate their optical and mechanical properties. Thin i-BN films were formed by ion beam deposition and radio-frequency (RF) sputtering on several substrate materials including Ag- and Al-coated glass and fused quartz. It was concluded that ion-beam-deposited BN coatings are not presently useful for front-beam-deposited BN coatings are not presently useful for front-surface mirrors designed for the visible and near-UV spectral regions.