A light-emitting array and its driving circuitry are integrated into a single device. The driving circuitry (21,23,25 and 27) is formed in a semiconductor substrate (20) and has an array of output terminals (not visible) on a surface of the substrate. Organic electroluminescent elements (50) are formed directly over the output terminals, in electrical contact with the output terminals. The electroluminescent elements (50) are driven by direct current. An optical head assembly has one or more of these light-emitting arrays mounted on a printed circuit board.