What Is Dichroic Glass?

The word “Dichroic” put simply means two colored. In terms of glass, it means that a beam of light that is transmitted through the glass is one color and a completely different color when it is reflected. This is accomplished by crystalizing metal oxides in a very thin layer on one side of a sheet of glass. This creates a light filter that transmits certain wavelengths of light while at the same time reflecting other wavelengths of light.

fused-glass-exampleDichroic glass is made with multiple thin layers of metal oxides that are vaporized by an electron beam in a vacuum chamber. These thin layers are essentially sealed on one by one to the face of a sheet of glass in a specific order and thickness which results in different colors of glass. Although it is called dichroic glass, meaning two colors, it often creates a wide range of colors that shift depending on the angle that the glass is viewed at.

How Dichroic Glass Was Developed

Dichroic glass was first developed by NASA in the 1950’s. Its main use was to protect sensitive spacecraft instruments and humans from the harmful effects of cosmic radiation when in space. The iconic symbol of NASA using dichroic glass was in the early space suits that used yellowish dichroic glass face shields. The glass allows astronauts to see without the risk of damaging their vision with cosmic radiation.

The stunningly beautiful glass was acquired by artists who starting using the spectacular color changing glass in stained glass windows, jewelry, and a number of other art forms. One of the most popular art forms using dichroic glass today is called fused glass. In this process, dichroic glass is added to other pieces of dichroic glass or non-dichroic glass, heated in a kiln until it fuses, cooled slowly to prevent cracking, and worked into jewelry. Fused glass designs have been used to make pendants, bracelets, earrings, wine stoppers, plates, and much more.