FAST WIDE-ANGLE LENS Russian patent published in 1995 - IPC

FIELD: optical instrument engineering. SUBSTANCE: fast wide-angle lens has two lens groups. The first group has positive lens and negative meniscus, which is turned with its concavity to the image. The second group is separated by diaphragm, in front of which the positive meniscus is disposed and glued biconvex lens; the positive meniscus is turned with its concavity to the object. Glued biconvex lens is formed by biconvex lens and negative meniscus. Four singular components are disposed behind the diaphragm. The first component has to be the biconcave lens, the second one positive meniscus, turned with its concavity to the object, the third one is biconvex lens, and the fourth one is positive meniscus turned with its concavity to the image. EFFECT: improved accuracy. 3 dwg, 3 tbl