In optics, a lens is a transparent optical element that uses refraction to modify the path of light. Lenses are generally characterized by their shape, which dictates whether they are diverging or converging. Converging lenses, which are thicker in the center, bend parallel light rays inward toward a focal point, a principle utilized in telescopes and cameras. Conversely, diverging lenses, which are thinner in the center, spread incoming light rays outward. The study of lens geometry and material properties allows for the precise development of imaging systems that achieve varying degrees of magnification and resolution across the electromagnetic spectrum.