In an imaging system (5), illumination light output from light outputting units (9) is collected and reflected by optical members (11), and is distributed to a specified area. In the light distributed to the specified area, the farther a constituent point is from the light outputting units, the greater the intensity of illumination light reaching the constituent point is. In addition, the intensity is equal to or greater than a predetermined reference value. Since illumination light is distributed in the way described above in the imaging system, the intensity of light incident on each pixel constituting a specified imaging area is equal to or greater than a reference intensity value, and the distribution of the intensities of light incident on the pixels constituting the specified imaging area is within a first reference range.