Geometric Optics — Lenses & Mirrors

Trace rays through lenses and discover image formation

Geometric optics models light as rays that travel in straight lines and bend at interfaces according to Snell's Law. A thin lens refracts parallel rays to converge at (convex) or diverge from (concave) the focal point. The thin lens equation 1/f = 1/v + 1/u relates the focal length, image distance, and object distance, while the magnification m = -v/u describes image size and orientation.