US Patent 7088485 Optical scanner and image formation apparatus

An optical scanner scans a surface of each of a plurality of latent image carriers by a corresponding light beam. The optical scanner includes a optical deflection unit that deflects and reflects light beams, the optical deflection unit having two or more surfaces that deflect and reflect the light beams in different directions, a lens that takes-in the light beams reflected from the optical deflection unit and divides the light beams into number of light beams equal to number of the image carrier, and an optical system corresponding to each image carrier, the optical system that guides the light beam output from the lens onto a surface of a corresponding one of the image carriers.