An image forming apparatus comprising a solid image-pickup device having a number of photoelectric conversion elements each for converting an image light incident thereto into an electrical signal representing an amount of the incident image light, and a number of storage cell elements each for storing charges in accordance with the electrical signal for forming and storing an optical latent image corresponding to the image light. The photoelectric conversion elements and the storage cell elements are arranged in a matrix form and each of the photoelectric conversion elements is integrally laminated on each of the storage cell elements, and a toner spray gun for supplying toners to developing surfaces of the storage cell elements to develop the optical latent image.