We have fabricated a bi-layer (SiO and MgF2) anti-reflection coating for fixed wavelength laser on synthetic fused silica and observed its performance. These coatings are found very hard, durable, easy evaporation, adherent and a peak transmission 99.9% at the design wavelength at normal incidence. Coatings can stand a long time without any deterioration even in the high power Copper Vapor Lasers (CVL) upto 300 watts. These coatings are produced by the thermal evaporation in high vacuum and the optical thickness of the each layer is quarter wave controlled by optical monitoring system.