Order (of an optic)
Classification of an optic according to its focal length.
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)
Classification of an optic according to its focal length.
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)
International Association of Marine Aids to Navigation and Lighthouse Authorities - AISM