Ultra-Low Density Aerogel Mirror Substrates
Abstract
Despite the extremely low density and the hence low weight of aerogel materials, the applicability of these materials to reflective applications has had little attention due to the high porosities exhibited by the materials. This high porosity yields an intrinsically rough but uniform surface topology for aerogel of density in the low hundreds of milligrams per cubic centimeter and a fractal surface geometry for lower density aerogel (densities of the order of tens of milligrams per cubic centimeter). This paper presents new results of aerogel materials used as ultra-light substrates for reflective coatings by way of surface machining, polishing and planarization prior to metalization, and the optical characterization thereof. This paper presents a significant advance in the ability to polish and subsequently apply a thin film coating to low density aerogel materials, thus yielding ultra lightweight mirrors. The effects of ionizing radiation upon the aerogel heterostructures are found to be remarkably minimal up to a threshold of 35 Mrad y-ray irradiation. An exponential correlation was found to predict radiation effects at high y-doses.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1993
- Accession Number
- ADA266128
Entities
People
- S. P. Hotaling
Organizations
- Rome Laboratory