Anti-reflective coatings(AR) Single Layer MgF2 Anti-Reflective CoatingMagnesium fluoride(MgF2) is probably the most widely used thin film material for optical coatings. Its performance is not outstanding but represents a significant improvement over an uncoated surface. It is the most commonly used, low-cost anti-reflection coating, and widely used in Lens & Prism, Input & output surface.