Optical Illusion with Portraits of Charles II and His Daughter Christine of Lorraine1593
Oil on prismatic panels, glass, 82 x 112 cm
Istituto e Museo di Storia della Scienza, Florence
This is one of the few known examples of a painted optical illusion, obtained by fastening a panel composed of painted triangular, prismatic strips of wood to a framework. The pieces are arranged so that a portrait of Charles II of Lorraine appears when the panel is observed from above, looking downwards, or one of his daughters, the Grand Duchess Cristina (Christine), wife of Ferdinando I de' Medici, if the object is viewed from below or using a special mirror.