Double Slit Experiment

The double slit experiment Two pointlike sources (blue dots) of waves (light green circles) are located at a distance to each other. Each source emits waves at wavelength . You can change both and to see what happens. Dark green spots are mark the places where the interference of the two waves in constructive, i.e. where the amplitude of the resulting wave is the maximum. Waves travel and crash against a screen (in magenta).
What happens when you shrink the distance between the sources? What if you change the wavelength?