Deposition Sciences Inc. (DSI), a manufacturer of thin-film optical coatings, has introduced its HeatBuster line of cold mirrors that withstand light levels above 200 W per square centimeter and extreme temperatures above 400 °C. HeatBuster cold mirrors feature reflectivity values of up to 98 percent across the visible spectrum and extremely low reflectivity in the infrared, with transmission of equal to or less than 20 percent in the 800 to 2500 nm waveband. They can be designed to operate over a wide range of angles and be applied to both infrared transparent substrates (e.g., glass, fused silica and sapphire) and opaque materials (e.g., stainless steel and electroformed nickel). DSI’s cold-mirror coatings efficiently reflect visible light without changing the color appearance of the source. The coatings can also be applied to the highly curved surfaces of parabolic and elliptical reflectors, meeting or surpassing strict adhesion standards. The new “white light” coatings are ideal for use in fold-mirror and light-tunnel applications, in which a focused light beam is needed to reduce the size of the optics and the overall unit.