Spherical lenses produce blurred imaging spots due to spherical aberration, while aspherical lenses deliver extremely sharp focus. Therefore, aspherical lenses can replace spherical lens groups to correct aberrations. For example, a zoom lens that normally uses ten spherical lenses can be replaced with just one or two aspherical lenses to achieve the same or better optical performance, lower production costs, and make the system lighter and more compact. Reducing the number of lenses also lowers requirements for mechanical tolerances, additional alignment steps, and anti-reflection coatings, improving overall usability and reducing total system design costs.
Aspherical optical components are increasingly important in optical systems requiring large field of view, large aperture, high aberration correction, compact structure, or special performance demands, thanks to their excellent optical properties.