When light from a monochromatic source is incident on a single narrow slit, it gets diffracted and a pattern of alternate bright and dark fringes is obtained on screen, called Diffraction Pattern of single slit. In diffraction pattern of single slit, it is found that
(i) Central bright fringe is of maximum intensity and the intensity of any secondary bright fringe decreases with increase in its order.
(ii) Central bright fringe is twice as wide as any other secondary bright or dark fringe.