a natural phenomenon involving the physical properties of matter and energy

an optical phenomenon resulting from the failure of a lens or mirror to produce a good image

a dark band in the spectrum of white light that has been transmitted through a substance that exhibits absorption at selective wavelengths

when light passes sharp edges or goes through narrow slits the rays are deflected and produce fringes of light and dark bands

one of the light or dark bands produced by the interference and diffraction of light

the striking of a light beam on a surface