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Manufacture Of Cylindrical Lenses

The demand for cylindrical lenses and reflectors with precise surfaces has prompted an investigation into manufacturing techniques which is still underway. The paper describes the findings so far in such areas as curve generation, coarse and fine grinding, and polishing. The effects of various type of generation on subsequent manufacturing processes are also being considered. Inspection techniques for cylindrical surfaces, including test glasses, Foucault tests and performance tests are also being investigated. The design and construction of machinery for the grinding and polishing operations, as well as generating, will be described, giving consideration to the geometry, requirements for rigidity, lack of chatter, types of motion, accuracy required for various processes and differences from conventional spherical grinding. The design and manufacture of grinding tools and laps, as well as the precisions required for various stages will also be discussed.