The image of two black spiders above is created by interference, and is an example of an interference pattern. The figures which are interfering are four points (and the rays which go with them), two close together on the right, and two close together on the left, but with the two pairs in different orientations. Each point has 240 rays emanating from it, and the rays are equidistant (in terms of angle measure), making each of these rays one euclid (1.5º) apart from its nearest neighbors.