An imaging system serving as an image generation device is provided with: a random optical filter array that has a plurality of types of optical filters and a scattering unit; photodiodes that receive light transmitted through the random optical filter array; an AD conversion unit that converts the light received by the photodiodes, into digital data; and a color image generation circuit that generates an image, using the digital data and modulation information of the random optical filter array, in which the scattering unit is located between the plurality of types of optical filters and the photodiodes, and in which the scattering unit includes a material having a first refractive index, and a material having a second refractive index that is different from the first refractive index.