The deflection and decomposition of light in passing by the edges of opaque bodies or through narrow slits, causing the appearance of parallel bands or fringes of prismatic colors, as by the action of a grating of fine lines or bars.
A phenomenon that occurs whenever a wave is obstructed in any way. Often diffraction fringes can be seen when a small aperature or object blocks light waves. Scientists use diffraction gratings to break up light into many wavelengths.
Diffraction, the deviation of light from rectilinear propagation, is a characteristic of wave phenomena which occurs when a portion of a wave front is obstructed in some way. When various portions of a wave front propagate past some obstacle, and interfere at a later point past the obstacle, the pattern formed is called a diffraction pattern.