Sterling Precision Optics Inc. - Evanston, ILManufactures optical components including filters, lenses, mirrors, and windows. Stocks optical glass, color filter glass, and fused silica. In-house tempering, coating, and custom machining. Other products include prisms, beamsplitters, cylindrical lenses, wedges, rods, tubes, reflectors, and optical assemblies. ISO 9001:2015 certified.