Accession Number:

ADA030871

Title:

Adsorption and Condensation of Water on Mirror and Lens Surfaces

Descriptive Note:

Final rept.

Corporate Author:

NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s):

Report Date:

1976-09-01

Pagination or Media Count:

21.0

Abstract:

This is a report of a literature search on adsorption and condensation of water on mirror and lens surfaces. Adsorbed water films on clean surfaces are generally 3.0 nm thick and can be ignored when considering absorption losses. When the surfaces are exposed to ambient conditions, various aerosols of dusts and hygroscopic particles are deposited on the surfaces which give rise to small losses by scattering of the incident radiation. In the case of hygroscopic particles the problem can be especially troublesome because here the scattering magnitude is a function of the relative humidity. For a given aerosol deposit an optical system containing a 6 mirror train will have a cumulative reflectivity decrease of about 7 as the relative humidity varies from 60 to 80.

Subject Categories:

  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE