This invention relates to a ranging apparatus capable of ranging simultaneously to a three dimensional scene. An illumination means (22) illuminates a scene with a two dimensional array of spots (12). A detector (6) is located near to the illumination means (22) and arranged to look toward the scene. A processor (7) responds to the output from the detector (6) and, from the location of a spot in the image of the scene, determines the range to that spot. A variety of techniques are used to resolve ambiguity in determining which projected spot is being considered.