Geometrical Optics

If you’ve ever used a microscope or been examined by an optometrist, you have probably been exposed to geometrical optics, a field that attempts to describe the propagation of light in terms of rays, which are abstractions that serve to approximate the path of light propagation. Although these are simplifications, they are extremely useful in practice, and the approximation is quite good when the wavelength of light relative to the structures it interacts with is small. The techniques are particularly useful in describing geometrical aspects of imaging, including optical aberrations. This lecture will provide you with a framework for understanding the path of light through mirrors and lenses.