Lou Metcalf
Dichroic glass is a glass containing multiple micro-layers of metal oxides, with a total thickness of three to five millionths of an inch, which gives the glass dichroic optical properties. NASA developed dichroic glass for use in satellite mirrors. Multiple ultra-thin layers of different metal oxides (gold, silver, titanium, chromium, aluminium, zirconium, magnesium, silicon) are evaporated on to the surface of the glass in a vacuum chamber. Based on which oxide is used, certain wavelengths of light will either pass through or be reflected, causing an array of colors to be visible.