Cr-ew optical provides windows of various materials, including colorless optical glass, colored optical glass, fused quartz, CaF2, sapphire, tempered glass, etc. Window products are diversified, including round square window, vacuum coating window, laser protection window, Brewster window, high-efficiency three prevention window, high-efficiency anti fog window, cross division window, UV protection window, filter window, beam splitting and color separation window, which can provide various coating services.