An optical lens is a transparent object, usually made of glass or plastic, that bends light rays to focus or disperse them. Lenses are commonly used in devices like cameras, glasses, and microscopes to improve vision or magnify images. They come in various shapes, such as convex (curved outward) and concave (curved inward), each serving different purposes in manipulating light. The primary function of an optical lens is to change the direction of light. This property is essential in many applications, including eyeglasses for correcting vision, telescopes for observing distant objects, and projectors for displaying images on larger screens.