A particularly bright future is predicted for LEDs that emit white light. In future, they are expected to be used in a wide range of applications, for example in street lamps, liquid-crystal displays, advertising boards, automotive headlights and building illumination. Their main advantages over incandescent bulbs and discharge lamps are that they consume less energy and have a longer service life. Lenses with free-form surfaces that have non-symmetrical geometries make particularly suitable optics for these LEDs. Unlike multi-component classic lens systems, only one of these lenses is required to focus the LED light with very low losses.