Diffraction of Light

The diffraction tutorial explores diffraction through a slit and is very simple to operate. The wavelength of the beam can be adjusted with the "Wavelength" slider on the left. The aperture size can be adjusted with the "Aperture" slider on the right. The aperture slider is the color of the selected wavelength.

In this experiment, visible monochromatic light passes through the slit and impinges on dark film produces the single-slit diffraction pattern.

In this experiment, the location of dark fringes is given by the equation:

dsinφm = ±mλ (m = 1,2,...)

where φm is the angle of a fringe of the order m. Note that m=0 not included among the values of m that give intensity minima. Indeed, m=0 corresponds to the center of the pattern, or the middle of the central maximum. The two dark fringes on either side of the central bright fringe correspond to m=1, and are called the first-order intensity minima, and so on.

Contributing Authors

Mortimer Abramowitz - Olympus America, Inc., Two Corporate Center Drive., Melville, New York, 11747.

Matthew J. Parry-Hill and Michael W. Davidson - National High Magnetic Field Laboratory, 1800 East Paul Dirac Dr., The Florida State University, Tallahassee, Florida, 32310.