Probably, it's known as [Lens flare](http://en.wikipedia.org/wiki/Lens_flare). A short googling would have provided your answer. Wikipedia has a good article on it. It happens when light reception takes place through lenses (both cameras and eyes). This image gives somewhat better idea about Lens flare... Here, the actual light rays are shown above. The interfering light rays from a bright source at some short angle is below. Here, the light source is outside the frame... ![enter image description here][1] The number of rays and their direction depends on the angle of incidence. [1]: https://i.sstatic.net/PptCL.gif Lens flares could be prevented using lens hoods.