The depth of field of an erecting equal-magnification lens array unit as a whole is expanded. An erecting equal-magnification lens array unit (13) includes a first lens array (17) and a second lens array (18). The first lens array (17) includes a plurality of first lenses (20). The first lenses are arranged in the first lens array (17) along a first direction. The first direction is perpendicular to the optical axes of the first lenses (20). The second lens array (18) includes a plurality of second lenses. The optical axes of the second lenses overlap with the optical axes of the first lenses. The second lenses are arranged in the second lens array (18) along the first direction. Each first lens (20) and second lens with overlapping optical axes form an optical system.