Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Anodically Produced Multiple Oxide Films for Increasing the Reflectance of Evaporated Aluminum

Not Accessible

Your library or personal account may give you access

Abstract

The paper describes a method for preparing reflectance-increasing film pairs of Al2O3 and TiO2 on evaporated aluminum mirrors. With one film pair of Al2O3 and TiO2, each film effectively one-quarter wavelength thick, the visible reflectance of aluminum can be increased by 5 percent. To produce such a multilayer coating, TiO2 is evaporated onto freshly deposited aluminum until the aluminum reflectance decreases to a minimum at λ=620 mµ. The direct evaporation of TiO2 results in a slightly reduced, strongly absorbing film material (TiOx). By anodic treatment in an electrolyte, such as 3 percent ammonium tartrate, the absorbing TiOx on aluminum can be oxidized to nonabsorbing TiO2, and part of the aluminum can be converted to Al2O3 underneath the TiO2. Seventy-five volts must be applied to produce quarter-wavelength thick films of Al2O3 and TiO2 at λ=530 mµ. Al2O3–TiO2 coatings furnish better protection than the most frequently used MgF2–ZnS film pairs. Two film pairs of Al2O3 and TiO2 can also be applied in one anodic process.

© 1954 Optical Society of America

Full Article  |  PDF Article
More Like This
Optical Properties of Silicon Monoxide in the Wavelength Region from 0.24 to 14.0 Microns*

Georg Hass and Calvin D. Salzberg
J. Opt. Soc. Am. 44(3) 181-187 (1954)

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Figures (8)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Tables (3)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Equations (4)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved