Optical coatings on glass for preserving artworks from illumination induced damage: design and testing

The deteriorating effect of light on artworks exposed in museums and galleries has been noticed for many years. A number of methods, which act on the illumination source, are presently in use to reduce the damage. A complementary approach is proposed here that consists in blocking the radiation, outside the range of sensitivity of the human eye, before it reaches the artwork. This result can be achieved by an optical coating deposited on the glass pane that is usually put in front of the artworks to protect them from vandalism. In addition to the preservation from illumination induced damage, the proposed coating is also able to improve the observation of the artwork by reducing the reflection effects of uncoated glass. Optical, colorimetric and psychophysical measurements on test samples are reported.