A wire grid polarizer comprises parallel grids of composite wires wherein each grid includes a coating stack having at least one high refractive index material coated on an aluminum layer. The coating stack comprising at least one high refractive index material reduces the reflection of the wire grid polarizer from between 40-50% to between 5-10%. Possible candidates for the high refractive index materials include Ge, Si and alloys of these materials having refractive indices greater than 3 with extinction coefficients above 0.2.