An imaging device installed on an autonomously movable body which comprises an image-taking section for taking images of the surrounding environment, and an object detecting section for detecting objects and obstacles by processing the obtained images. The imaging device comprises: an image processing section to perform color detection of the images taken by the image-taking section; a white calibration plate for the image-taking section to perform color correction; and a calibration plate control section for moving the calibration plate into a field of view of the image-taking section, wherein it is determined whether color information which is sufficient to perform color detection is obtainable from the images taken by the image-taking section, and color correction is performed using the calibration plate when it is determined that the images taken by the image-taking section do not provide color information sufficient to perform color detection.