Erecting equal-magnification lens array unit, image reading device and image forming device

摘要

An erecting equal-magnification lens array unit includes a first lens array and a second lens array. The first lens array includes a plurality of first lenses. The second lens array includes a plurality of second lenses. The optical axes of the second lenses overlap with the optical axes of the first lenses. Each first lens and second lens with overlapping optical axes form a unit optical system. Each unit optical system is an erecting equal-magnification optical system. Each unit optical system is substantially telecentric on at least the object side. The imaging position, by each first lens, of an object is positioned between the first lens array and the second lens array.

主权项

1. An erecting equal-magnification lens array unit comprising:
a first lens array including a plurality of first lenses, the first lenses being arranged along a first direction perpendicular to optical axes of the first lenses; and a second lens array including a plurality of second lenses, optical axes of the second lenses overlapping with optical axes of the first lenses, the second lenses being arranged along the first direction, wherein each optical system formed by each first lens and each second lens with overlapping optical axes is an erecting equal-magnification optical system, each optical system is substantially telecentric on at least an object side, the first lens array and the second lens array are connected so that an imaging position, by each first lens, of an object at a predetermined ideal distance from each optical system is positioned between the first lens array and the second lens array, and the expression 0.1×F