PURPOSE:To well correct astigmatism and to decrease the image blur in the peripheral part by curvature of field by forming the refracting face of a meniscus positive lens of double-face refracting faces and curving the image pickup plane according to the curvature of field of the meniscus positive lens. CONSTITUTION:This lens consists, successively from an object side, of a positive single lens of a meniscus shape the convex face of which is directed to the object side, a stop, and the image pickup plane having the curvature corresponding to the curvature of field. The meniscus positive lens which is a photographic lens is the double-face aspherical face lens and the image pickup plane refers to the plane such as the image pickup plane of a photographic film or CCD, etc., on which the formed image is detected and recorded. Namely, there is the limit in the improvement of the curvature of field by using the aspherical faces but the limitation is offset by providing the curvature to the image pickup plane. The astigmatism is corrected by the aspherical face lens in this way and the curvature of field is removed by the curvature of the image pickup plane. The good images having the lessened astigmatism are thus obtd. over the entire surface of the image plane.
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