This article proposes an optics teaching method, especially related to interference phenomena, which is adequate to be used in physics classes at high-school level. The method is based on the so-called "Lloyd's mirror'' experiment, which leads to a connection between geometric and physical optics, which is much simpler than the "Young double-slit experiment''. In the experiment reported in this article, there is an observation of interference between a light beam coming from the source and another light beam coming from a mirror reflection. Values of measurements of the wave length of light were close to 700 nm, which is in reasonable agreement with standard experimental values. It is concluded that this experiment is a fine, simple, although underused, way to show the interference of light in the classroom.
optics; physics teaching; lloyd's mirror
