In A Sunday Afternoon on the Island of La Grande Jatte, Georges Seurat contrasted miniature dots or small brushstrokes of colors that when unified optically in the human eye were perceived as a single shade or hue. He believed that this form of painting, called divisionism at the time but now known as pointillism, would make the colors more brilliant and powerful than standard brushstrokes.
French artist Bernard Pras is widely known for his unbelievable found-object installations. In anamorphic artworks like these, he hides his images in piles of what seems to be plain junk. They can only be seen through a particular device or just from a right angle.