1. An image projection device, comprising: a drive controller that causes generation of light of a specified color tone by a combination of light to be transmitted by a liquid crystal panel to project image data onto a projection plane; a camera configured to capture an image of the image data projected on the projection plane; an image capturing controller that receives, from the drive controller, a synchronization signal that specifies a period in which the liquid crystal panel does not transmit light, and causes capturing of the image of the image data projected on the projection plane by the camera according to the period specified by the synchronization signal, wherein a drive frequency to drive the liquid crystal panel is equal to a drive frequency to perform exposure with the camera; an illuminated image detector that detects, from the captured image of the image data, an illuminated image that is illuminated by an illuminating device on the projection plane; and an illuminated image generator that generates projection image data obtained by superimposing new image data at a position in which the illuminated image is detected.