BS 4779:1971

Adopts OTF measurement as an objective test method for ascertaining and expressing the performance of optical devices and systems, including image forming systems or assemblies and lenses but does not normally relate to the separate parts of a multi-component system. Specifically limited to tests on lens or mirror image-forming systems or combinations of both. Methods considered employ localized apertures such as slits or edges, or an extended periodic screen such as a grating. Guidance for operation of OTF measuring equipment is also given.