Light



Visible light ranges from Red to Violet

Below Red in the spectrum is Infrared (Radiant Heat), this is slightly less energetic than visible light. The longer wave length heating region is reflected by glass.

Above Violet light is Ultraviolet, the light responsible for tanning and the bleaching of colours. Window glass blocks about 90% of the high energy UV that penetrates the atmosphere, but passes enough to cause damage to fabrics and art.