PURPOSE:To suppress small the occurrence of various aberrations in the wide-angle lens and achieve the miniaturization of the wide-angle lens by giving relatively weak negative power as the lens system of this class to the front group of the lens system. CONSTITUTION:The back focus fB maintains the neighborhood of 1.5 times the composite focal length f and yet this lens satisfies aperture ratio F2.8 and angle of view 84 deg. and is constituted by 8-group 8-element lenses. A positive meniscus single lens L1 is disposed to the 1st group and negative meniscus single lenses L2, L3 are disposed to the 2nd and 3rd groups to form the front group. A positive single lens L4 is disposed to the 4th group, a biconvex positive single lens L5 to the 5th group, a biconcave negative single lens L6 to the 6th group, a meniscus positive single lens L7 to the 7th group and a biconvex positive single lens L8 to the 8th group to form the rear group. All conditions of formulas (1)-(8) are satisfied. The retrofocus type wide-angle lens of small production of various aberrations and small- size front lens diameter and others is obtained.
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