An aspheric lens is a type of optical lens that has a non-spherical surface. Unlike traditional spherical lenses that have a constant curvature across their surface, aspheric lenses have a varying curvature that allows them to correct for aberrations and improve image quality. One advantage of aspheric lenses is that they can reduce the number of lenses needed in an optical system, making them lighter and more compact. Additionally, aspheric lenses can be designed to have a wider field of view.