ABSTRACT
Fresnel lenses are commonly used in lighthouses, theatrical spotlights, and as the illumination plates for the ubiquitous overhead projector. The groove widths, besides being the most prominent characteristic in the appearance of a Fresnel lens, define the basic optical performance of the lens. Fabrication techniques vary considerably depending on the lens optical properties. Glass lenses are fabricated using glass-molding techniques. Plastic lenses are primarily fabricated by diamond turning.
