Three-dimensional information is presented directly on the surface of a target three-dimensional object without using a display device such as a display monitor and an HUD. Spatially coded light patterns are projected from two projectors on a target object surface. The light projected from the two projectors are added up on the object surface to produce unified color and luminance. On the object surface, light is simply added up, so that a pattern whose color and brightness correspond to distance and height appears. Hence, a distance to an object or a three-dimensional shape of an object can be highlighted by the color and brightness presented on the object for perception by human beings.