Aspherical lenses have rotationally symmetrical optics around the optical axis, whose radius of curvature changes radially with the distance from the center. This allows optical systems to achieve high image quality, whereby the number of elements required decreases and that saves on both costs and weight. However, for manufacturers, testing the aspheric shape accuracy, which means the quality of these types of lenses, is a considerable challenge: It requires measuring the tiniest deviations in shape in the nanometer range while making short measuring and setup times possible. Read more and watch the video
