Hyperbolas from Light Fixtures

When you see light from a fixture shining against a wall, you often observe some very clear, sharp curves as the boundaries between light and dark areas. Those curves are generally hyperbolas. Why? The light from the source is generally blocked off to produce a cone of light, and then that cone is intersected with the wall, creating a conic section. For typical arrangements of light fixtures, that section is generally a hyperbola.

Leave a Reply