An aspheric lens or asphere is a lens whose surfaces have a profile that is neither a portion of a sphere nor of a circular cylinder. In photography, a lens assembly that includes an aspheric element is often called an aspherical lens. A lens. ... A sphere is a perfectly symmetrical geometrical object. ... A right circular cylinder In mathematics, a cylinder is a quadric, i. ... Photography is the process of making pictures by means of the action of light. ...

The asphere's more complex surface profile can eliminate spherical aberration and reduce other optical aberrations compared to a simple lens. A single aspheric lens can often replace a much more complex multi-lens system. The resulting device is smaller and lighter, and possibly cheaper than the multi-lens design. Small glass or plastic aspheric lenses can be made by molding, which allows cheap mass production. Due to their low cost and good performance, molded aspheres are commonly used in inexpensive consumer cameras, camera phones, and CD players. They are also commonly used for laser diode collimation, and for coupling light into and out of optical fibers. Focal plane Longitudinal sections In optics, spherical aberration is an image imperfection that occurs due to the increased refraction of light rays that occurs when rays strike a lens or mirror near its edge, in comparison with those that strike nearer the center. ... This article needs to be cleaned up to conform to a higher standard of quality. ... A simple lens is a lens consisting of a single simple element. ... A camera is a device used to take pictures (usually photographs), either singly or in sequence, with or without sound recording, such as with video cameras. ... A packaged laser diode with penny for scale. ... Optical fibers An optical fiber (or fibre) is a transparent thin fiber, usually made of glass or plastic, for transmitting light. ...

Larger aspheres can be made by diamond turning, a process in which a computer-controlled lathe directly cuts the desired profile into a piece of glass or another optical material. This is a slow process. A faster and newer technology is deterministic microgrinding, where computer-controlled grinding wheels are used to shape the aspheric profile which is then polished to the final shape. Lenses produced by these techniques are used in telescopes, projection TV's, missile guidance systems, and scientific research instruments. Diamond turning is a process of mechanical machining of precision elements using Computer Numerical Control (CNC) lathes equipped with natural or synthetic diamond-tipped cutting elements. ... Conventional metalworking lathe In woodturning, metalworking, metal spinning, and glassworking, a lathe is a machine tool which spins a block of material so that when abrasive, cutting, or deformation tools are applied to the block, it can be shaped to produce an object which has rotational symmetry about an axis... 50 cm refracting telescope at Nice Observatory. ... Braun HF 1, Germany, 1958. ...

Another method for producing aspheric lenses is by depositing optical resin onto a spherical lens to form a composite lens of aspherical shape.