For conducting laboratory experiments on Fresnel diffraction, the use of a simple point light source from an LED and the application of a modern smartphone for photographing the diffraction patterns are proposed. The developed devices allow the experiments to be carried out under normal laboratory lighting.

Students form a more exact idea of the action of optical mirrors if they can observe the wave field being formed during reflection. For this purpose it is possible to organize model experiments with flexural waves propagating in thin elastic plates. The direct and round edges of the plates are used as models of plane, convex and concave mirrors.…