Young’s two-slits experiment
This animation creates the propagating 2D radiative field produced by two coherent point sources, which can be considered to be the slits in the famous Young’s two-slit experiment. The movie begins with a single central oscillating source, which after five cycles, begins to separate as two sources up to eight wavelengths separation (note that the intensity is plotted, hence 16 fringes can be seen between the sources at the end). On the right, the far-field interference pattern is also plotted, which follows the expression , whereby d is the separation of the slits and b is their width. The slits width is set to be equal to the wavelength (i.e., a quasi point source). The profile on the right is the calculated far-field curve rather than the profile on the right hand edge of the interference pattern, as the far-field condition there is only poorly met for the larger source separations, d.