| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact image reading device with a large depth of field.SOLUTION: An image reading device includes a light source 2, an image-forming optical system 1, an imaging element part 41, a memory 5, and a processing device 6; and the image-forming optical system 1 has a plurality of cells 11, each of which is an individual optical system, arranged in a main scanning direction 211 and in two lines in a sub-scanning direction 212. Each of the cells has a first reflection type light-collecting optical element 100, a first plane mirror 105, an aperture 101, and a second reflection type light-collecting optical element 102 arranged in this order from a document 7; and the plurality of first plane mirrors belonging to the plurality of cells are mirror parts formed on a single planar substrate. |
