Wikipedia
Cove lighting
Cove lighting is a form of indirect lighting built into ledges, recesses, or valences in a ceiling or high on the walls of a room. It directs light up towards the ceiling and down adjacent walls. It may be used as primary lighting, or for aesthetic accent, especially to highlight decorative ceilings. Cove lighting is valued because it hides the fixtures, and because it provides a very even, warm light.