Refractive errors in the eye can create starbursts, or a sequence of concentric rays or thin filaments emanating from intense lights. Starbursts surrounding light are most evident at night and can be produced by eye disorders such as cataracts or corneal edema, or they can be a result of eye surgery. The cause is unclear but may have to do with reflections off of the retina itself or from within it. Starburst patterns are often seen in photographs or videos taken at night with a flashlight. This occurs when light from the distant object reaches the eye and is refracted (bent) by the lens. Some of this light travels through the fluid inside the lens and gets reflected back into the lens from the front surface. This reflection creates a new image close up of the flashlight that leaves a trail behind it as it moves across the room. A similar effect happens with light entering the eye from directly ahead. It too is bent by the lens and some of it is reflected backwards toward the source. The pattern left by the moving flashlight is called "coastal lighting" because it looks like lights on a coastline at night. This effect can also be seen with a laser pointer if it is not kept still. If you move your head around while looking at the location of the pointer, you will see it trace out a series of starbursts. There are several other causes for starbursts besides coastal lighting.