aspheric surface
Quick Summary
An aspheric surface in optics is a nonspherical surface used on lenses or mirrors. While plane and spherical surfaces are easiest to produce, aspheric surfaces are sometimes necessary to correct specific aberrations, or optical defects, in imaging systems.1
Spherical aberration occurs when the outer parts of a lens do not focus light rays as precisely as the central part, leading to unsharp images, especially at large apertures. Using an aspheric surface, which has a variable curvature, can help correct this. Transparent plastics are also used to mold elements with aspheric surfaces, though they are more susceptible to damage than glass.234
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- opticsNonclassical imaging systems
…familiar of these is the aspheric (nonspherical) surface. Because plane and spherical surfaces are the easiest to generate accurately on glass, most lenses contain only such surfaces. It is occasionally necessary, however, to use some other axially symmetric surface on a lens or mirror, generally to correct a particular aberration.…
Read More…familiar of these is the aspheric (nonspherical) surface. Because plane and spherical surfaces are the easiest to generate accurately on glass, most lenses contain only such surfaces. It is occasionally necessary, however, to use some other axially symmetric surface on a lens or mirror, generally to correct a particular aberration.…
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technology of photographyOptical performance…surfaces of a lens system aspheric; i.e., with the variable curvature of a paraboloid or other surface rather than the constant curvature of a spherical one.
Read More…surfaces of a lens system aspheric; i.e., with the variable curvature of a paraboloid or other surface rather than the constant curvature of a spherical one.
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