The diffraction pattern will look something like the aperture (a slit, circle, square) but it will be surrounded by some diffracted waves that give it a 'fuzzy' appearance. When a source of waves, such as a light bulb, sends a beam through an opening or aperture, a diffraction pattern will appear on a screen placed behind the aperture. Instead, there is a gray area along the edge that was created by light that was 'bent' or diffracted at the side of the pole. But careful observation of the shadow's edge will reveal that the change from dark to light is not abrupt. From a distance the darkened zone of the shadow gives the impression that light traveling in a straight line from the Sun was blocked by the pole.
Consider the shadow of a flagpole cast by the Sun on the ground.
All waves are subject to diffraction when they encounter an obstacle in their path.
