The traditional way to shield an optic from glint is to use a long, tubular lens shade. The problem is, if a shade is long enough to effectively shield the optic from glint, it can be too long and bulky for practical use in the field.
Tenebraex ARDs work by a clustering a large number tiny tubes into a honeycomb-like grid. The length-to-width ratio of these tubes has a certain selected relationship to the field of view of the optical system.
With this unique geometry, there is no vignetting or reduction in the field-of-view, light reduction is only on the order of 15%, any loss in resolution is imperceptible, and glint is eliminated. Tenebraex ARDs also act to shield the interior of an optic from the sun's rays, thus reducing internal glare and making for a clearer view when looking up-sun.
Tenebraex ARDs work well on visible light optics such as rifle scopes and binoculars, as well as on night vision optics and thermal sights.
Elcan Specter Anti-Reflection Devices
Tenebraex ARDs are currently deployed and in use by U.S. military forces, police and anti-terrorist teams, as well as by serious hunters and sports shooters.