An image forming apparatus is capable of printing half-toned images of high quality. The image forming apparatus includes a photoconductive body and a light emitting element array. A plurality of light emitting elements is aligned in the light emitting element array. Each light emitting element array emits light to form an electrostatic latent image of a pixel on the photoconductive drum. A controller controllably drives the plurality of light emitting elements to form the electrostatic latent image, each pixel being formed by a combination of a total of N (N>1) light emitting elements. Each element of the N light emitting elements is driven with a different amount of energy from remainders of the N light emitting elements.