CONTRAST ENHANCEMENT FILTER AND METHOD

摘要

Contrast enhancement filter having first and second transparent glass substrates with first and second surfaces with the first surface of each facing the medium in which the filter is disposed. A sheet-like circular polarizer is provided formed of stretched plastic members covered by layers of cellulose acetate butyrate. The circular polarizer is disposed between the first and second glass substrates and faces the second surfaces of the glass substrates. A dried plastisol primer layer is disposed on the surface of the layers of cellulose acetate butyrate facing the glass substrates. First and second layers of polyvinyl butyral adhesive secure the layers of cellulose acetate butyrate carried by the circular polarizer with the primer layers thereon to the second surfaces of the glass substrates. An anti-reflection coating is disposed on the first surface of the first substrate.