1. An imaging device comprising: an imaging lens that forms an image of an object; an image sensor that includes a photodetector cell array in which a plurality of photodetector cells are disposed in an array; a rotation device that rotates the image of the object and the image sensor relative to each other; a lens array for generating disparity images, the lens array being provided between the imaging lens and the image sensor, and the lens array including a plurality of lenses that are disposed in an array; and a processor comprising hardware, wherein the processor acquires rotation information that represents a relative direction of the image of the object and the image sensor, and generates the disparity images based on the acquired rotation information and image information obtained from the image sensor.