The energy that is not absorbed is the color that we see. Dichroic Art Glass creates its effect in a completely different way. It is made from materials that are completely transparent, meaning they do not adsorb any appreciable light energy in the visible spectrum. This lack of adsorption is responsible for the clean crisp colors evident in dichroic glass. Dichroic glass actually works with reflections.
White light is the sum of all the colors in the visible light spectrum.
This is the same way nature creates the colors seen in bird feathers, fish scales, opals and even the color seen on an oil slick on water. We emulate the natural effect with the principals of Optical Thin Film Physics. We know that reflections are created when light traveling through a media of one optical index of refraction and encounters a media of a different optical index of refraction, a reflection occurs. The index of refraction can be visualized as a measurement of the resistance to the light as it travels through a media. The intensity of the reflection is going to be proportional to the difference of indices.