Do you know why the sky is blue? Article defines scattering and how it works. Explains the difference between the scattering of light and reflection or refraction.

A description of the early lights used in lighthouses and how these lights evolved into what they are today. Explains the contributions of Fresnel to the development of these lights; discusses the Fresnel orders.

This animation depicts the path of light to each person's eye. Different people are sighting in different directions; yet each person is sighting at the same image location. In this animation the image location is the intersection point...

The principle of total internal reflection is discussed in this article. The appearance of objects from inside the water of a swimming pool is compared to the path of light in a fiber optic cable.