Interactive Simulator · Through the Gap

Diffraction Through a Gap

Plane wavefronts reach a gap in a barrier. On the far side the part that passes straight through stays flat in the middle, while the wave curves outward from each edge of the gap. How much it spreads depends on the gap compared with the wavelength. A wide gap stays almost straight. As the gap narrows toward one wavelength the wavefronts curl into near semicircles. Tune the gap and wavelength to reach the target amount of diffraction.

Mission Set up strong diffraction. Round 1Streak 0Best 0
Narrowing the gap toward one wavelength makes the spreading:
gap width120
wavelength40
gap ÷ wavelength3.0
diffractionmoderate
most diffraction when the gap is about one wavelength wide.