Obtained are an imaging optical system having a simple structure in which imaging position deviation due to deformation caused by a weight of an off-axial optical element is reduced and an image reading apparatus using the same. According to an imaging optical system for image reading, image information...http://www.google.com/patents/US7570444?utm_source=gb-gplus-sharePatent US7570444 - Imaging optical system and image reading apparatus using the same
