Custom fabricated sapphire windows that are clear as glass and nearly hard as diamond to provide optimum front surface protection for cameras, sensors, and other devices are available from Meller Optics, Inc. of Providence, RI. Meller Sapphire Windows feature transmission from the UV to IR (270 nm to 4.7 microns), are water-clear, second only to diamond in hardness (Mohs 9), and can withstand up to 1,000°C. Ideally suited for windows and lenses used in harsh environments, sapphire provides optimum front surface protection from fast moving dirt, sand, water, and most chemicals. Manufactured in sizes up to 10” dia., depending upon diameter-to-thickness aspect ratio, Meller Sapphire Windows provide flatness to 1/10th wave in the visible and < 2 arc sec. in./in. parallelism with finishes from 60-40 to 40-20 scratch-dig, depending upon configuration. Applications include viewing optics in cameras, weapons, refractometers, and machine inspection. Meller Sapphire Optics are priced according to configuration and quantity. Literature and price quotations are available upon request.