A lithophane (French: lithophanie) is an etched or molded artwork in very thin translucent porcelain that can only be seen clearly when back lit with a light source.

The photos used

Tree by the lake, Szedres (HU)
Coop's Shot Tower, Melbourne (AU)
Osaka Castle, Osaka (JP)
Luna Park, Sydney
Great Egret, Lake Wollumboola
Noh mask, Kyoto (JP)