1. An image capturing module comprising: a plurality of image capturing systems, each including an optical system and capturing an image of a subject by light in a wavelength region different from each other to generate a wavelength component signal representing an image of light in the corresponding wavelength region; and an image generating section that combines the wavelength component signals generated by the plurality of image capturing systems thereby generating an image signal representing an image of the subject, wherein a plurality of first image capturing systems, from among the plurality of image capturing systems, which generate a wavelength component signal having a greater contribution to brightness in the image of the subject, include an optical system having a deeper focal depth, and the plurality of first image capturing systems are the greatest in number among the plurality of image capturing systems, and include optical systems having a smallest diaphragm among the plurality of image capturing systems.