1. Introduction
Thomas Young’s original experiments on the diffraction
and interference of light in the early years
of the 19th century were decisive in proving the
wave-like nature of light [1].
Generally, the concept is demonstrated in the
classroom in a very similar manner to Young’s
original experiments, and usually the double
slit experiment is used. Nowadays, cheap and
widely available laser sources are increasingly
used instead of lamps, with the advantage that
their monochromatic light produces very clearly
defined nodes in the fringes without the need for a
filter [2]. However, little else has changed, and the
screens and splitting devices are still pretty much
specialist equipment that must be bought for the
classroom.