Aspheric lenses encompass any object that does not belong to a sphere, but when we use this term here, we are specifically discussing a subset of aspheric lenses, which are rotationally symmetric optical elements with a radius of curvature that changes radially according to the center of the lens.
The aspheric approach can improve image quality, reduce the number of components required, and reduce the cost of optical design. From digital cameras and CD players to high-end microscope objectives and fluorescent microscopes, aspherical lenses have developed rapidly in all aspects of optics, imaging or Photonics. This is because aspherical lenses have many unique and significant advantages over traditional spherical optical elements.