Dieter Villinger / Artwork  1856

Scotchlite consists of microscopic hollow beads made of clear glass. When the beads cool down at the end of the manufacturing process, the glass contracts. During this process, the inside of the beads curls up due to the reduction in surface area. This creates an optical phenomenon similar to that seen in snow crystals.
When one of these beads is viewed under a microscope, spectral colours become visible which, when added together, appear white to our eyes under normal conditions. So we see white even though there is no white there.
Scotchlite also has the property of reflecting light very strongly. This is particularly noticeable at dusk. While the white of a wall slowly turns grey, the Scotchlite stands out in comparison as a brighter white.