An imaging means mounted on a vehicle performs imaging resulting in grayscale images having brightness values corresponding to object temperature, and objects around the vehicle are detected from said images. On the basis of said grayscale images, display images to be displayed on a display device mounted on the vehicle are generated and displayed on the display device. The display images are generated by lowering the brightness of areas not corresponding to the objects detected in the grayscale images. The display device is positioned in the vehicle width direction at no more than a prescribed distance away from an imaginary line passing through the center of rotation of the vehicle steering wheel and extending in the longitudinal direction of the vehicle. Accordingly, because display images are generated in which only the objects are spotlighted, the driver can quickly comprehend the objects present when using a display device.