Dichroic glass

"Dichroic" is defined as the property of having more than one color, especially when viewed from different angles or from transmitted to reflected light. Dichroic coated glass is produced by a process called "thin film physics" and is generally referred to as a color separator. It's normally used as an interference filter in scientific measuring or correcting applications. To get this effect, thin layers of metallic oxides, such as titanium, silicon, and magnesium are deposited upon the surface of the glass in a high temperature, vacuum furnace.