Concave Parabolic Mirror
This is Southmoore's Pasco Ray Box showing what happens when visible light bounces off a parabolic mirror. It isn't super clear, but you can see that the light coming in from the right is reflected towards a single point about halfway back to the light box. This mirror is appropriate for visible light, and thus just looks like a mirror. But it's function is the same as the parabolic reflector seen in the previous slide, which reflects radio waves. The antennas are put near the focal point, where the intensity is the strongest.
Concave Parabolic Mirror
This is Southmoore's Pasco Ray Box showing what happens when visible light bounces off a parabolic mirror. It isn't super clear, but you can see that the light coming in from the right is reflected towards a single point about halfway back to the light box. This mirror is appropriate for visible light, and thus just looks like a mirror. But it's function is the same as the parabolic reflector seen in the previous slide, which reflects radio waves. The antennas are put near the focal point, where the intensity is the strongest.