The thinned-array curse (sometimes, sparse-array curse) is a theorem in electromagnetic theory of antennas. It states that a transmitting antenna which is synthesized from a coherent phased array of smaller antenna apertures that are spaced apart will have a smaller minimum beam spot size. Typically, the main lobe has a solid angle that is smaller by an amount proportional to the ratio of the area of the synthesized array to the total area of the individual apertures. The amount of power that is beamed into this main lobe is reduced by an exactly proportional amount, so that the total power density in the beam is constant.