Aluminum surfaces for technical lighting purposes

Abstract

Reflector for technical lighting purposes, having a reflecting surface of aluminum and a protective, transparent, pore-free barrier layer of aluminum oxide produced by anodizing having a dielectric constant .epsilon. of 6 to 10.5 at 20.degree. C., where the barrier layer is of thickness d that either satisfies the condition a) for constructive interference: d.multidot.n=k.multidot..lambda./2.+-.20 nm or b) for achieving a color-toned reflector surface: ›k.multidot..lambda./2+20 nm!<d.multidot.n<›(k+1).multidot..lambda./2-20 nm ! or c) for using as starting material to produce reflectors with LI/HI multi-layer coatings that increase reflectivity. d.multidot.n=l.multidot..lambda./4.+-.20 nm where n is the refractive index of the barrier layer, .lambda. is the average wave length of the light striking the surface of the reflector, k is a natural number and l is a natural number that is uneven. The thickness of the barrier layer lies between 60 and 490 nm and does not vary by more than .+-.5% over the whole of the aluminum surface.

Dependencies are inferred from the claim text.