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The term aspheric mirror literally means a mirror that is not spherical. More-specific terms like parabolic mirror, hyperbolic mirror, and flat mirror are generally used for specific mirrors to which they apply, the term aspheric used when speaking of properties applying to them in general, or for shapes without such a well-known specific term. The mirror shapes in astronomical optics often termed aspheric are mirrors that simultaneously incorporate two types of curvature, with one dominating in the center of the mirror and another dominating toward the edges. Some optics designs that eliminate various aberrations make good use of use such aspheric mirrors or aspheric lenses, i.e., lenses incorporating such curves. The Schwarzschild telescope incorporates such an aspheric mirror and the Schmidt corrector plate of the Schmidt telescope is such an aspheric lens.
Outside astronomy, a common use of the term aspheric mirror is for a type of automobile side mirror that includes a such a (non-spherical, non-flat) curve, typically part flat and part convex-cylindrical. It makes visible adjacent vehicles that would otherwise be out of view.