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Optical manufacturing and testing is the process of manufacturing and testing optical components. It spans a wide range of manufacturing procedures and optical test configurations. The manufacture of a conventional spherical lens typically begins with the generation of the optic's rough shape by grinding a glass blank. [1]
Optical lens design is the process of designing a lens to meet a set of performance requirements and constraints, including cost and manufacturing limitations. Parameters include surface profile types (spherical, aspheric, holographic, diffractive, etc.), as well as radius of curvature, distance to the next surface, material type and optionally tilt and decenter.
These imperfections are part of the surface and cannot be removed by cleaning. Surface quality is characterized either by the American military standard notation (eg "60-40") or by specifying RMS (root mean square) roughness (eg "0.3 nm RMS"). [1] American notation focuses on how visible surface defects are, and is a "cosmetic" specification.
For example, an important characteristic of a lens is the form of the optical surface. In the case of aspherical lenses the measurement of optical surfaces is very difficult and connected to high efforts. Additionally, when working with tactile measurement systems there is always a risk that the optical surface might be scratched.
After many years as rivals, Essel and Silor merged on 1 January 1972 to form Essilor, then the world's third-largest ophthalmic optical firm. [1] Its first year of existence was marked by the creation of Valoptec, a non-trading company composed of stockholder managers who held half the company's capital stock, and the purchase of Benoist-Bethiot, a French lens manufacturer specializing in ...
Hoya Corporation (Hoya株式会社, Hōya Kabushiki-gaisha) is a Japanese company manufacturing optical products such as photomasks, photomask blanks and hard disk drive platters, contact lenses and eyeglass lenses for the health-care market, [4] medical photonics, [5] lasers, photographic filters, medical flexible endoscopy equipment, and software.
The majority of 35 mm film systems, cameras, telecine equipment, optical printers, or projectors, are configured to accommodate the 4-perf system; each frame of 35 mm is 4 perforations long. 4-perf was (and remains) the traditional system, and the majority of projectors are based on 4-perf, because 4 perforations is the amount needed per frame vertically in order to have enough negative space ...
Surface plates are a common tool in the manufacturing industry and are often fitted with mounting points so that it can be an integrated structural element of a machine such as a coordinate-measuring machine, precision optical assembly, or other high precision scientific & industrial machine. Plates are typically square or rectangular, although ...